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CAESAR II Technical Reference Manual Copyright © 1993-2004 COADE, Inc. All Rights Reserved.

Printed on 18 November, 2003

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Contents Chapter 1: Introduction

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Overview ......................................................................................................................................................2 Program Support / User Assistance ..............................................................................................................3 COADE Technical Support ..........................................................................................................................4

Chapter 2: Configuration and Environment

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Generation of the CAESAR II Configuration File........................................................................................2 Computation Control ....................................................................................................................................3 Use Pressure Stiffening .....................................................................................................................3 Missing Mass ZPA ............................................................................................................................3 Bend Axial Shape ..............................................................................................................................3 Rod Tolerance (degrees)....................................................................................................................4 Rod Increment (degrees) ...................................................................................................................4 Alpha Tolerance ................................................................................................................................4 Ambient Temperature........................................................................................................................4 Friction Stiffness ...............................................................................................................................4 Friction Normal Force Variation .......................................................................................................5 Friction Angle Variation....................................................................................................................5 Friction Slide Multiplier ....................................................................................................................5 Coefficient of Friction (Mu) ..............................................................................................................5 WRC-107 Version .............................................................................................................................5 WRC-107 Interpolation Method........................................................................................................5 Incore Numerical Check ....................................................................................................................5 Decomposition Singularity Tolerance ...............................................................................................6 Minimum Wall Mill Tolerance (%)...................................................................................................6 Bourdon Pressure...............................................................................................................................7 Ignore Spring Hanger Stiffness .........................................................................................................7 Include Spring Stiffness in Hanger OPE Travel Cases......................................................................7 Hanger Default Restraint Stiffness ....................................................................................................8 Default Translational Restraint Stiffness...........................................................................................8 Default Rotational Restraint Stiffness ...............................................................................................8 SIFs and Stresses ..........................................................................................................................................9 Default Code......................................................................................................................................9 Occasional Load Factor ...................................................................................................................10 Yield Stress Criterion ......................................................................................................................11 B31.3 Sustained Case SIF Factor ....................................................................................................12 B31.3 Welding and Contour Insert Tees Meet B16.9......................................................................13 Allow User's SIF at Bend ................................................................................................................13 Use WRC329...................................................................................................................................13 Use Schneider ..................................................................................................................................13 All Cases Corroded..........................................................................................................................13 Liberal Expansion Stress Allowable................................................................................................14 WRC 329 .........................................................................................................................................14 Base Hoop Stress On ( ID/OD/Mean/Lamés ).................................................................................14 Use PD/4t ........................................................................................................................................14

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Contents Add F/A in Stresses .........................................................................................................................14 Add Torsion in SL Stress.................................................................................................................15 Stress Stiffening Due to Pressure ....................................................................................................15 Reduced Intersection .......................................................................................................................16 Class 1 Branch Flexibility ...............................................................................................................17 B31.1 Reduced Z Fix.......................................................................................................................17 Schneider .........................................................................................................................................17 No RFT/WLT in Reduced Fitting SIFs ...........................................................................................17 Apply B31.8 Note 2.........................................................................................................................17 Pressure Variation in Expansion Cases ...........................................................................................17 Geometry Directives ...................................................................................................................................18 Connect Geometry Through Cnodes ...............................................................................................18 Auto Node Number Increment ........................................................................................................18 Z-Axis Vertical ................................................................................................................................19 Minimum Allowed Bend Angle ......................................................................................................19 Maximum Allowed Bend Angle......................................................................................................19 Bend Length Attachment Percent ....................................................................................................19 Minimum Angle to Adjacent Bend..................................................................................................19 Loop Closure Tolerance ..................................................................................................................19 Horizontal Thermal Bowing Tolerance ...........................................................................................20 Plot Colors ..................................................................................................................................................21 OPENGL Switch .............................................................................................................................21 Pipes ................................................................................................................................................21 Nodes...............................................................................................................................................21 Rigids/Bends....................................................................................................................................21 Hangers/Nozzles..............................................................................................................................22 Structure ..........................................................................................................................................22 Background......................................................................................................................................22 Axes.................................................................................................................................................22 Labels ..............................................................................................................................................22 Highlights ........................................................................................................................................22 Displaced Shape ..............................................................................................................................22 Stress Level 1 ..................................................................................................................................22 Stress Level 2 ..................................................................................................................................22 Stress Level 3 ..................................................................................................................................22 Stress Level 4 ..................................................................................................................................22 Stress Level 5 ..................................................................................................................................22 Stress < Level 1 ...............................................................................................................................23 Stress > Level 1 ...............................................................................................................................23 Stress > Level 2 ...............................................................................................................................23 Stress > Level 3 ...............................................................................................................................23 Stress > Level 4 ...............................................................................................................................23 Stress > Level 5 ...............................................................................................................................23 FRP Pipe Properties ....................................................................................................................................24 Use FRP SIF ....................................................................................................................................24 Use FRP Flexibilities.......................................................................................................................24 FRP Property Data File....................................................................................................................25 BS 7159 Pressure Stiffening............................................................................................................25 FRP Laminate Type.........................................................................................................................25 Exclude f2 from UKOOA Bending Stress.......................................................................................26 FRP Pipe Density ............................................................................................................................26 FRP Alpha (e-06) ............................................................................................................................26 FRP Modulus of Elasticity ..............................................................................................................26 Ratio Shear Mod:Emod ...................................................................................................................26 Axial Strain:Hoop Stress (Ea/Eh*Vh/a) ..........................................................................................26

Contents

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Database Definitions...................................................................................................................................27 Structural Database..........................................................................................................................27 Piping Size Specification (ANSI/JIS/DIN/BS)................................................................................27 Valves and Flanges..........................................................................................................................27 Expansion Joints ..............................................................................................................................28 Units File Name...............................................................................................................................28 Load Case Template ........................................................................................................................28 System Directory Name...................................................................................................................28 Default Spring Hanger Table...........................................................................................................28 Enable Data Export to ODBC-Compliant Databases ......................................................................28 Append Reruns to Existing Data .....................................................................................................29 ODBC Compliant Database Name ..................................................................................................29 Miscellaneous .............................................................................................................................................30 Output Table of Contents ................................................................................................................30 Output Reports by Load Case..........................................................................................................30 Displacement Reports Sorted by Nodes ..........................................................................................30 Time History Animation..................................................................................................................31 Dynamic Example Input Text..........................................................................................................31 Memory Allocated...........................................................................................................................31 User ID ............................................................................................................................................31 Disable "File Open" Graphic Thumbnail.........................................................................................31 Disable Undo/Redo Ability .............................................................................................................32 Enable Autosave ..............................................................................................................................32 Autosave Time Interval ...................................................................................................................32 Prompted Autosave .........................................................................................................................32 Set/Change Password..................................................................................................................................33 Access Protected Data .....................................................................................................................33 New Password .................................................................................................................................33 Change Password.............................................................................................................................33 Remove Password ...........................................................................................................................33 Units File Operations ..................................................................................................................................34 Make Units File ...............................................................................................................................34 Review Existing Units File..............................................................................................................34 Create a New Units File...................................................................................................................35 Existing File to Start From ..............................................................................................................36 New Units File Name ......................................................................................................................36 View/Edit File .................................................................................................................................36 Convert Input to New Units........................................................................................................................37 Name of the Input File to Convert...................................................................................................37 Name of the Units File to Use .........................................................................................................37 Name of the Converted File.............................................................................................................37 Material Database .......................................................................................................................................38 Material - Add .................................................................................................................................38 Material - Delete..............................................................................................................................38 Material - Edit..................................................................................................................................39

Chapter 3: Piping Screen Reference

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Piping Spreadsheet Data ...............................................................................................................................2 Help Screens and Units......................................................................................................................2 Auxiliary Fields - Component Information ................................................................................................14 Bends ...............................................................................................................................................14 Rigid Elements ................................................................................................................................18 Expansion Joints ..............................................................................................................................19

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Contents Reducers ..........................................................................................................................................20 SIFs & Tees .....................................................................................................................................22 Auxiliary Fields - Boundary Conditions.....................................................................................................31 Restraints .........................................................................................................................................31 Hangers............................................................................................................................................36 Nozzles .......................................................................................................................................................48 Nozzle Flexibility - WRC 297.........................................................................................................48 Displacements..................................................................................................................................57 Auxiliary Fields - Imposed Loads...............................................................................................................58 Forces and Moments........................................................................................................................58 Uniform Loads.................................................................................................................................58 Wind Loads .....................................................................................................................................59 Wave Loads .....................................................................................................................................60 Auxiliary Fields - Piping Code Data...........................................................................................................62 Allowable Stresses...........................................................................................................................62 Available Commands..................................................................................................................................79 Break Command ..............................................................................................................................79 Valve/Flange Database ....................................................................................................................81 Find Distance...................................................................................................................................84 Find Element ...................................................................................................................................84 Global Coordinates ..........................................................................................................................85 Insert Element..................................................................................................................................85 Node Increment ...............................................................................................................................85 Show Informational Messages.........................................................................................................85 Tee SIF Scratchpad..........................................................................................................................85 Bend SIF Scratchpad .......................................................................................................................91 Expansion Joint Modeler .................................................................................................................95 Expansion Joint Modeler Notes.......................................................................................................98 Expansion Joint Design Notes .........................................................................................................99 Torsional Spring Rates ....................................................................................................................99 Bellows Application Notes ............................................................................................................100 Available Expansion Joint End-Types...........................................................................................100 Pressure Rating ..............................................................................................................................101 Expansion Joint Styles...................................................................................................................101 Materials ........................................................................................................................................102 Title Page.......................................................................................................................................103 Hanger Data...................................................................................................................................103 Special Execution Parameters........................................................................................................109 Combining Independent Piping Systems.......................................................................................119 List/ Edit Facility ...........................................................................................................................121 Block Operations ...........................................................................................................................123 Printing an Input Listing................................................................................................................126 Input Plotting .................................................................................................................................127 Model Rotation, Panning, and Zooming........................................................................................127 Views.............................................................................................................................................129 Volume Plotting.............................................................................................................................129 Displaying Element Information ...................................................................................................129

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Piping Input Graphics ...............................................................................................................................131 Static Output Graphics..............................................................................................................................134

Chapter 4: Structural Steel Modeler

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Overview ......................................................................................................................................................2 The Structural Steel Property Editor.............................................................................................................3 New File ............................................................................................................................................3 Units File ...........................................................................................................................................4 Vertical Axis......................................................................................................................................5 Material Properties ............................................................................................................................6 Cross Section (Section ID) ................................................................................................................7 Model Definition Method ................................................................................................................10 General Properties.......................................................................................................................................12 Add ..................................................................................................................................................12 Insert................................................................................................................................................12 Replace ............................................................................................................................................12 Delete...............................................................................................................................................12 UNITS Specification - UNIT......................................................................................................................13 Axis Orientation Vertical............................................................................................................................14 Material Identification - MATID ................................................................................................................15 MATID............................................................................................................................................15 YM...................................................................................................................................................15 POIS ................................................................................................................................................16 G ......................................................................................................................................................16 YS....................................................................................................................................................16 DENS...............................................................................................................................................16 ALPHA............................................................................................................................................16 Section Identification - SECID ...................................................................................................................17 Section ID........................................................................................................................................17 SECID .............................................................................................................................................17 Name ...............................................................................................................................................18 Setting Defaults - DEFAULT .....................................................................................................................19 Setting Nodes in Space - NODE, NFILL, NGEN.......................................................................................20 NODE ..............................................................................................................................................20 NFILL..............................................................................................................................................21 NGEN..............................................................................................................................................22 Building Elements - ELEM, EFILL, EGEN, EDIM...................................................................................24 ELEM ..............................................................................................................................................24 EFILL ..............................................................................................................................................25 EGEN ..............................................................................................................................................27 EDIM...............................................................................................................................................29 Resetting Element Strong Axis - ANGLE, ORIENT..................................................................................32 ANGLE ...........................................................................................................................................32 ORIENT ..........................................................................................................................................33 End Connection Information.......................................................................................................................35 Free End Connections - FREE.........................................................................................................35 Standard Structural Element Connections - BEAMS, BRACES, COLUMNS ...............................38 BRACES .........................................................................................................................................40 COLUMNS .....................................................................................................................................42 Defining Global Restraints - FIX ....................................................................................................44 Loads ..........................................................................................................................................................46 Point Loads - LOAD........................................................................................................................46 Uniform Loads - UNIF ....................................................................................................................48

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Contents Gravity Loads - GLOADS...............................................................................................................50 Wind Loads - WIND .......................................................................................................................51 Utilities .......................................................................................................................................................53 LIST.................................................................................................................................................53 Structural Databases ...................................................................................................................................54 AISC 1977 Database .......................................................................................................................55 AISC 1989 Database .......................................................................................................................61 German 1991 Database....................................................................................................................68 Australian 1990 Database................................................................................................................71 South African 1992 Database ..........................................................................................................73 Korean 1990 Database.....................................................................................................................74 UK 1993 Database...........................................................................................................................75

Chapter 5: Controlling the Dynamic Solution

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Dynamic Analysis Input ...............................................................................................................................2 Dynamic Analysis Overview ........................................................................................................................3 Random .............................................................................................................................................3 Harmonic ...........................................................................................................................................3 Impulse ..............................................................................................................................................6 Harmonic Analysis .......................................................................................................................................8 Excitation Frequencies ......................................................................................................................8 Harmonic Forces and Displacements ..............................................................................................11 Harmonic Displacements.................................................................................................................13 Response Spectra / Time History Load Profiles .........................................................................................16 Response Spectrum / Time History Profile Data Point Input ..........................................................21 Force Response Spectrum Definitions.............................................................................................22 Building Spectrum / Time History Load Cases ..........................................................................................24 Spectrum /Time History Profile.......................................................................................................24 Factor...............................................................................................................................................24 Direction ..........................................................................................................................................25 Combining Static and Dynamic Results ..........................................................................................32 Spectrum Time History...............................................................................................................................38 Force................................................................................................................................................38 Direction ..........................................................................................................................................38 Node ................................................................................................................................................38 Force Set #.......................................................................................................................................38 Lumped Masses ..........................................................................................................................................44 Mass.................................................................................................................................................44 Direction ..........................................................................................................................................44 Start Node........................................................................................................................................44 Stop Node ........................................................................................................................................45 Increment.........................................................................................................................................45 Snubbers ..........................................................................................................................................46 Dynamic Control Parameters......................................................................................................................48 Analysis Type (Harmonic/Spectrum/Modes/Time-History) ...........................................................49 Static Load Case for Nonlinear Restraint Status..............................................................................62 Stiffness Factor for Friction (0.0 - Not Used)..................................................................................63 Max. No. of Eigenvalues Calculated (0-Not used) ..........................................................................64 Frequency Cutoff (HZ) ....................................................................................................................67 Closely Spaced Mode Criteria/Time History Time Step (ms) .........................................................68 Load Duration (Time History or DSRSS Method) (Sec.)................................................................69 Damping (Time History or DSRSS) (Ratio of Critical) ..................................................................69 ZPA (Reg. Guide 1.60/UBC- G's)/# Time History Output Cases ...................................................71

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Re-use Last Eigensolution ...............................................................................................................73 Spatial or Modal Combination First ................................................................................................73 Spatial Combination Method (SRSS/ABS) .....................................................................................74 Modal Combination Method (GROUP/10%/DSRSS/ABS/SRSS)..................................................74 Include Pseudostatic (Anchor Movement) Components (Y/N) .......................................................77 Include Missing Mass Components (Y/N) ......................................................................................78 Pseudostatic (Anchor Movement) Comb. Method (SRSS/ABS).....................................................78 Missing Mass Combination Method (SRSS/ABS) ..........................................................................78 Directional Combination Method (SRSS/ABS) ..............................................................................79 Sturm Sequence Check on Computed Eigenvalues (Y/N)...............................................................79 Advanced Parameters .................................................................................................................................81 Estimated Number of Significant Figures in Eigenvalues ...............................................................81 Jacobi Sweep Tolerance ..................................................................................................................82 Decomposition Singularity Tolerance .............................................................................................82 Subspace Size (0-Not Used) ............................................................................................................82 No. to Converge Before Shift Allowed (0 - Not Used) ...................................................................83 No. of Iterations Per Shift (0 - Pgm computed) ...............................................................................83 Percent of Iterations Per Shift Before Orthogonalization ................................................................84 Force Orthogonalization After Convergence (Y/N) ........................................................................84 Use Out-Of-Core Eigensolver (Y/N)...............................................................................................84 Frequency Array Spaces ..................................................................................................................84 Pulsation Loads...........................................................................................................................................85 Relief Valve Thrust Load Analysis.............................................................................................................88 Relief Load Synthesis for Gases Greater Than 15 psig ...................................................................88 Relief Load Synthesis for Liquids ...................................................................................................94 Output From the Liquid Relief Load Synthesizer............................................................................96

Chapter 6: Technical Discussions

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Rigid Element Application ...........................................................................................................................2 Rigid Material Weight .......................................................................................................................2 Rigid Fluid Weight ............................................................................................................................2 Rigid Insulation Weight.....................................................................................................................2 Cold Spring...................................................................................................................................................4 Expansion Joints ...........................................................................................................................................7 Hanger Sizing Algorithm............................................................................................................................10 Spring Design Requirements ...........................................................................................................10 Restrained Weight Case...................................................................................................................10 Operating Case ................................................................................................................................11 Installed Load Case .........................................................................................................................11 Setting Up the Spring Load Cases ...................................................................................................12 Constant Effort Support...................................................................................................................12 Including the Spring Hanger Stiffness in the Design Algorithm .....................................................13 Other Notes on Hanger Sizing.........................................................................................................13 Class 1 Branch Flexibilities ........................................................................................................................14 Modeling Friction Effects ...........................................................................................................................17 Nonlinear Code Compliance.......................................................................................................................19 Sustained Stresses and Nonlinear Restraints ..............................................................................................20 Notes on Occasional Load Cases.....................................................................................................23 Static Seismic Loads...................................................................................................................................24 Wind Loads.................................................................................................................................................27 Elevation..........................................................................................................................................29 Hydrodynamic (Wave and Current) Loading .............................................................................................30 Ocean Wave Particulars...................................................................................................................31

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Contents Applicable Wave Theory Determination .........................................................................................32 Pseudo-Static Hydrodynamic Loading ............................................................................................32 AIRY Wave Theory Implementation ..............................................................................................33 STOKES Wave Theory Implementation .........................................................................................34 Stream Function Wave Theory Implementation..............................................................................34 Ocean Currents ................................................................................................................................34 Technical Notes on CAESAR II Hydrodynamic Loading...............................................................35 Input: Specifying Hydrodynamic Parameters in CAESAR II .........................................................39 Current Data ....................................................................................................................................39 Wave Data .......................................................................................................................................41 Seawater Data..................................................................................................................................42 Piping Element Data........................................................................................................................42 References .......................................................................................................................................42 Evaluating Vessel Stresses..........................................................................................................................44 ASME Section VIII Division 2 - Elastic Analysis of Nozzle ..........................................................44 Procedure to Perform Elastic Analyses of Nozzles .........................................................................46 Description of Alternate Simplified ASME Sect. VIII Div. 2 Nozzle Analysis ..............................47 Simplified ASME Sect. VIII Div. 2 Elastic Nozzle Analysis..........................................................48 Inclusion of Missing Mass Correction ........................................................................................................49 References .......................................................................................................................................52 Fatigue Analysis Using CAESAR II...........................................................................................................54 Fatigue Basics..................................................................................................................................54 Fatigue Analysis of Piping Systems ................................................................................................55 Static Analysis Fatigue Example .....................................................................................................56 Fatigue Capabilities in Dynamic Analysis.......................................................................................65 Creating the .FAT Files ...................................................................................................................67 Calculation of Fatigue Stresses........................................................................................................68 Pipe Stress Analysis of FRP Piping ............................................................................................................70 Underlying Theory ..........................................................................................................................70 FRP Analysis Using CAESAR II ....................................................................................................85 Code Compliance Considerations...............................................................................................................93 General Notes for All Codes ...........................................................................................................93 Code-Specific Notes ........................................................................................................................98 Local Coordinates .....................................................................................................................................127 Other Global Coordinate Systems .................................................................................................128 The Right Hand Rule.....................................................................................................................128 Pipe Stress Analysis Coordinate Systems......................................................................................130 Defining a Model...........................................................................................................................133 Using Local Coordinates ...............................................................................................................135 CAESAR II Local Coordinate Definitions ....................................................................................136 Applications - Utilizing Global and Local Coordinates.................................................................140 Transforming from Global to Local ..............................................................................................146 Frequently Asked Questions..........................................................................................................147

Chapter 7: Miscellaneous Processors

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Accounting....................................................................................................................................................2 Accounting File Structure..................................................................................................................8

Contents

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Batch Stream Processing ..............................................................................................................................9 CAESAR II Fatal Error Processing ............................................................................................................11

Chapter 8: Interfaces

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Overview of CAESAR II Interfaces .............................................................................................................2 CAD Interfaces .............................................................................................................................................4 CADWorx/PIPE Link........................................................................................................................4 DXF AutoCAD Interface...................................................................................................................4 CADPIPE Interface ...........................................................................................................................5 ComputerVision Interface ...............................................................................................................24 Intergraph Interface .........................................................................................................................26 PRO-ISO Interface ..........................................................................................................................64 PCF Interface...................................................................................................................................72 Generic Neutral Files ..................................................................................................................................74 CAESAR II Neutral File Interface ..................................................................................................74 Data Matrix Interface.......................................................................................................................94 Computational Interfaces ............................................................................................................................95 LIQT Interface.................................................................................................................................95 PIPENET Interface ........................................................................................................................100 Data Export to ODBC Compliant Databases ............................................................................................102 DSN Setup .....................................................................................................................................102 Controlling the Data Export ..........................................................................................................105 Data Export Wizard .......................................................................................................................106

Chapter 9: File Sets

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CAESAR II File Guide .................................................................................................................................2 CAESAR II Operational (Job) Data Files...................................................................................................14

Chapter 10: Update History

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CAESAR II Initial Capabilities (12/84)........................................................................................................2 CAESAR II Version 1.1S Features (2/86) ....................................................................................................3 CAESAR II Version 2.0A Features (10/86) .................................................................................................4 CAESAR II Version 2.1C Features (6/87)....................................................................................................5 CAESAR II Version 2.2B Features (9/88)....................................................................................................6 CAESAR II Version 3.0 Features (4/90) ......................................................................................................7 CAESAR II Version 3.1 Features (11/90) ....................................................................................................8 Graphics Updates...............................................................................................................................8 Rotating Equipment Report Updates .................................................................................................8 WRC 107 Updates.............................................................................................................................8 Miscellaneous Modifications.............................................................................................................8 CAESAR II Version 3.15 Features (9/91) ....................................................................................................9 Flange Leakage and Stress Calculations............................................................................................9 WRC 297 Local Stress Calculations..................................................................................................9 Stress Intensification Factor Scratchpad............................................................................................9 Miscellaneous ....................................................................................................................................9 CAESAR II Version 3.16 Features (12/91) ................................................................................................10 CAESAR II Version 3.17 Features (3/92) ..................................................................................................11 CAESAR II Version 3.18 Features (9/92) ..................................................................................................12 Codes and Databases .......................................................................................................................12

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Contents Interfaces Added..............................................................................................................................12 Miscellaneous Changes ...................................................................................................................12 CAESAR II Version 3.19 Features (3/93) ..................................................................................................14 CAESAR II Version 3.20 Features (10/93) ................................................................................................15 CAESAR II Version 3.21 Changes and Enhancements (7/94) ...................................................................16 CAESAR II Version 3.22 Changes & Enhancements (4/95)......................................................................18 CAESAR II Version 3.23 Changes (3/96) ..................................................................................................20 CAESAR II Version 3.24 Changes & Enhancements (3/97)......................................................................21 CAESAR II Version 4.00 Changes and Enhancements (1/98) ...................................................................24 CAESAR II Version 4.10 Changes and Enhancements (1/99) ...................................................................25 CAESAR II Version 4.20 Changes and Enhancements (2/00) ...................................................................26 CAESAR II Version 4.30 Changes and Enhancements (3/01) ...................................................................27 CAESAR II Version 4.40 Features .............................................................................................................28 CAESAR II Version 4.40 Technical Changes and Enhancements ( 5/02)..................................................29

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CHAPTER 1

Introduction In This Chapter Overview .....................................................................................2 Program Support / User Assistance .............................................3 COADE Technical Support.........................................................4

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CAESAR II Technical Reference Manual

Overview This CAESAR II Technical Reference Guide is the reference manual for CAESAR II. It presents the theory behind CAESAR II operations, and explains why certain tasks are performed. Users are urged to review the background material contained in this manual, especially when applying CAESAR II to unfamiliar types of analysis. Chapter 2 (see "Configuration and Environment" on page 1) discusses the configuration of CAESAR II and the resulting environment. This includes language support and program customization. In addition to the COADE supplied routines, several third-party diagnostic packages are also mentioned. Chapter 3 (see "Piping Screen Reference" on page 1), Piping Input Reference, contains images of program generated screens, and explains each input cell, menu option, and toolbar button. Also discussed in detail is the Plot Screen, which displays the input model graphically. Chapter 4 (see "Structural Steel Modeler" on page 1) examines the Structural Steel Modeler and describes all commands, toolbar buttons, menu items, and input fields. Chapter 5 (see "Controlling the Dynamic Solution" on page 1) discusses the Dynamic Input and Control Parameters: each input cell, toolbar button, and menu item is examined. The purpose and effects of the various Dynamic Control Parameters are detailed. Chapter 6 (see "Technical Discussions" on page 1) contains theoretical overviews of various technical methods used in CAESAR II. Both common and advanced modeling techniques are covered. Chapter 7 (see "Miscellaneous Processors" on page 1) provides information regarding a few miscellaneous auxiliary processors. Chapter 8 (see "Interfaces" on page 1) details interfaces between CAESAR II and other programs. Chapter 9 (see "File Sets" on page 1) presents a list of files associated with CAESAR II. Chapter 10 (see "Update History" on page 1) lists the CAESAR II update history.

Chapter 1 Introduction

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Program Support / User Assistance COADE’s staff understands that CAESAR II is not only a complex analysis tool but also, at times, an elaborate process—one that may not be obvious to the casual user. While our documentation is intended to address the questions raised regarding piping analysis, system modeling, and results interpretation, not all the answers can be quickly found in these volumes. COADE understands the engineer’s need to produce efficient, economical, and expeditious designs. To that end, COADE has a staff of helpful professionals ready to address any CAESAR II and piping issues raised by users. CAESAR II support is available by telephone, e-mail, fax, and the internet; literally hundreds of support calls are answered every week. COADE provides this service at no additional charge to the user. It is expected, however, that questions focus on the current version of the program. Formal training in CAESAR II and pipe stress analysis is also available from COADE. COADE schedules regular training classes in Houston and provides in-house and open attendance training around the world. These courses focus on the expertise available at COADE — modeling, analysis, and design.

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CAESAR II Technical Reference Manual

COADE Technical Support Phone: 281-890-4566

E-mail: [email protected]

Fax:

WEB: www.coade.com (http://www.coade.com/c2articles/c2_faq_ web.html)

281-890-3301

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CHAPTER 2

Configuration and Environment In This Chapter Generation of the CAESAR II Configuration File ......................2 Computation Control...................................................................3 SIFs and Stresses.........................................................................9 Geometry Directives....................................................................18 Plot Colors...................................................................................21 FRP Pipe Properties ....................................................................24 Database Definitions ...................................................................27 Miscellaneous..............................................................................30 Set/Change Password ..................................................................33 Units File Operations ..................................................................34 Convert Input to New Units ........................................................37 Material Database........................................................................38

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CAESAR II Technical Reference Manual

Generation of the CAESAR II Configuration File Each time CAESAR II starts, the configuration file caesar.cfg is read from the current data directory. If this file is not found in the current data directory, the installation directory is searched for the configuration file. If the configuration file is not found, a fatal error will be generated and CAESAR II will terminate. The configuration or setup file contains directives that dictate how CAESAR II will operate on a particular computer and how it will perform a particular analysis. The caesar.cfg file is generated by selecting TOOLS/CONFIGURE/SETUP (or the Configure button from the toolbar) from the CAESAR II Main Menu. Note: You must click the Exit w/Save button on the bottom of the Configure/Setup window to create a new configuration file or to save changes to the existing configuration file. The configuration program produces the Computation Control (on page 3) window. Use the tabs to navigate to the appropriate configuration spreadsheets.

Important: The caesar.cfg file may vary from machine to machine and many of the setup directives modify the analysis. Do not expect the same input file to produce identical results between machines unless the setup files are identical. It is advised that a copy of the setup file be archived with input and output data so that identical reruns can be made. The units file, if modified by the user, would also need to be identical if the same results are to be produced. The following section explains the CAESAR II setup file options. They are grouped as they appear when chosen from the tabs on the Configure window.

Chapter 2 Configuration and Environment

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Computation Control

Computational Control Configuration Settings

Use Pressure Stiffening This flag enables CAESAR II to include pressure-stiffening effects in those codes that do not explicitly require its use. In these cases pressure-stiffening effects will apply to all bends, elbows, and both miter types. In all cases, the pressure used is the maximum of all pressures defined for the element.

Missing Mass ZPA The default for this option is Extracted, which means that CAESAR II will use the spectrum value at the last “extracted” mode. Changing this value to SPECTRUM instructs CAESAR II to use the last spectrum value as the ZPA for the missing mass computations.

Bend Axial Shape For bends 45 degrees or smaller, a major contributor to deformation can be the axial displacement of the short-arched pipe. With the axial shape function disabled this displacement mode is ignored and the bend will be stiffer.

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CAESAR II Technical Reference Manual

Rod Tolerance (degrees) The angular plus-or-minus permitted convergence error. Unless the change from iteration “n” to iteration “n+1” is less this value, the rod will NOT be converged. The default of CAESAR II is 1.0 degree. For systems subject to large horizontal displacements, values of 5.0 degrees for convergence tolerances have been used successfully.

Rod Increment (degrees) The maximum amount of angular change that any one support can experience between iterations. For difficult-to-converge problems, values of 0.1 have proven effective here. When small values are used, however, the user should be prepared for a large number of iterations. The total number of iterations can be estimated from: Est. No. Iterations = 1.5(x)/(r)/(Rod Increment) Where: x - maximum horizontal displacement at any one rod. r - rod length at that support

Alpha Tolerance The breakpoint at which CAESAR II decides that the entry in the Temp fields on the input spreadsheet is a thermal expansion coefficient or a temperature. The default is 0.05. This means that any entry in the Temp fields whose absolute magnitude is less than 0.05 is taken to be a thermal expansion coefficient in terms of inches per inch (dimensionless). Use of this field provides some interesting modeling tools. If an Alpha Tolerance of 1.1 is set, then an entry in the Temp 2 field of -1 causes the element defined by this expansion coefficient to shrink to zero length. This alternate method of specifying cold spring is quite useful in jobs having hanger design with cold spring (see chapter 6 (see "Technical Discussions" on page 1) for more details regarding Cold Spring).

Ambient Temperature

If 0.0 is entered here, the default ambient temperature for all elements in the system is (degrees ^07) . If this does not accurately represent the installed, or zero expansion strain state, then enter a different value in this field.

Friction Stiffness Friction restraint stiffness. The default is 1E6 lb/in. This value is used when a friction restraint is "nonsliding." In the "non-sliding" state, stiffnesses are inserted in the two directions perpendicular to the restraint’s line of action and opposing any sliding motion. This is the first parameter that should be adjusted to help a slowly converging problem where friction is suspected. Lower stiffness values permit more "non-sliding" movement, but given the indeterminate nature of the friction problem in general, this error is not considered crucial.

Chapter 2 Configuration and Environment

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Friction Normal Force Variation This tolerance, default of 0.15, or 15 percent, is the amount of variation in the normal force that is permitted before an adjustment will be made in the sliding friction force. This value normally should not be adjusted.

Friction Angle Variation Friction sliding angle variation. The default is 15 degrees. This parameter had more significance in versions prior to 2.1. This parameter is currently only used in the first iteration when a restraint goes from the non-sliding to sliding state. All subsequent iterations compensate for the angle variation automatically.

Friction Slide Multiplier This is an internal friction sliding force multiplier and should never be adjusted by the user unless so directed by a member of the COADE/CAESAR II support staff.

Coefficient of Friction (Mu) The value specified here is applied by default as the coefficient of friction to all translational restraints. Specifying a value of zero, the default, means that no friction is applied.

WRC-107 Version This directive sets the Version of the WRC-107 bulletin used in the computations. Valid options are: August 1965 March 1979 March 1979 with the 1B1-1 and 2B-1 off axis curves (default)

WRC-107 Interpolation Method The curves in WRC Bulletin 107 cover essentially all applications of nozzles in vessels or piping; however, should any of the interpolation parameters i.e., U, Beta, etc. fall outside the limits of the available curves then some extension of the WRC method must be used. The default is to use the last value in the particular WRC table. Alternatively, the user may control this extensions methodology interactively. This causes the program to prompt the user for curve values when necessary.

Incore Numerical Check Enables the in-core solution module to test the stability of the solution for the current model and loadings. This option, if enabled, adds the solution of an extra load case to the job stream.

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Decomposition Singularity Tolerance The default value is 1.0 e+10. CAESAR II checks the ratio of off-diagonal coefficients to the on-diagonal coefficient in the row. If this ratio is greater than the decomposition singularity tolerance, then a numerical error may occur. This problem does not have to be associated with a system singularity. This condition can exist when very small, and/or long pipes are connected to very short, and/or large pipes. The out-ofcore solution will, however, stop with a singularity message. This solution abort will prevent any possibility of an errant solution. These solutions have several general characteristics: When machine precision errors of this type occur they are very local in nature, affecting only a single element or very small part of the model, and are readily noticeable upon inspection. The 1E10 limit can be increased to 1E11 or 1E12 and still provide a reasonable check on solution accuracy. Any solution computed after this limit has been increased should always be checked closely for “reasonableness.” At 1E11 or 1E12 the number of significant figures in the local solution has been reduced to two or three. The 1E10 limit can be increased to 1E20 or 1E30 to get the job to run, but the user should remember that the possibility for a locally errant solution exists when stiffness ratios are allowed to get this high. Solutions should be carefully checked.

Minimum Wall Mill Tolerance (%) Use this directive is to specify the default percentage of wall thickness allowed for mill and other mechanical tolerances. Note: For most piping codes, this value is only used during the "minimum wall thickness" computation. Mill tolerance is usually not considered in the flexibility analysis. By default this value is 12.5, corresponding to a 12.5% tolerance. To eliminate mill tolerance consideration, set this directive to 0.0.

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Bourdon Pressure Select the BOURDON PRESSURE EFFECT from the drop list. The BOURDON EFFECT causes straight pipe to elongate, and bends to "OPEN UP" translationally along a line connecting the curvature end points. If the BOURDON EFFECT is not activated there will be no global displacements due to pressure.

BOURDON PRESSURE OPTION #1 (TRANSLATION ONLY) includes only translational effects.

BOURDON PRESSURE OPTION #2 (TRANSLATION & ROTATION) includes translational and rotational effects on bends. OPTION #2 may apply for bends that are formed or rolled from straight pipe, where the bend cross section will be slightly oval due to the bending process.

Note: OPTION #1 is the same as OPTION #2 for straight pipe. For elbows, OPTION #1 should apply for forged and welded fittings where the bend cross section can be considered essentially circular.

Note: The BOURDON EFFECT (translation only) is always considered when FRP pipe is used, regardless of the actual setting of the BOURDON FLAG.

Ignore Spring Hanger Stiffness Enabling this option causes CAESAR II to ignore the stiffness of spring hangers in the analysis. This option is consistent with hand computation methods of spring hanger design, which ignored the effects of the springs. Important:

COADE recommends that this value never be changed.

Include Spring Stiffness in Hanger OPE Travel Cases Enabling this option defaults CAESAR II to place the designed spring stiffness into the Hanger Operating Travel Case and iterate until the system balances. This iteration scheme therefore considers the effect of the spring hanger stiffness on the thermal growth of the system (vertical travel of the spring). If this option is used, it is very important that the hanger load in the cold case (in the physical system) be adjusted to match the reported hanger Cold Load. Disabling this option defaults the program to design spring hangers the traditional way.

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Hanger Default Restraint Stiffness

Where hangers are adjacent to other supports or are themselves very close (for example where there are two hangers on either side of a trunnion support), the CAESAR II hanger design algorithm may generate poorly distributed hot hanger loads in the vicinity of the close hangers. Using a more flexible support for computing the hanger restrained weight loads often allows the design algorithm to more effectively distribute the system’s weight. A typical entry is 50,000; the default value is (1.0E12 lb/in).

Default Translational Restraint Stiffness

This directive defines the value used for non-specified translational restraint stiffnesses. By default this value is assumed to be (1.0E12 lb./in).

Default Rotational Restraint Stiffness

This directive defines the value used for non-specified rotational restraint stiffnesses. By default this value is assumed to be (1.0E12 in-lb/deg).

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SIFs and Stresses

SIFs and Stresses Configuration Settings

Default Code The piping code the user designs to most often should go here. This code will be used as the default if no code is specified in the problem input. The default piping code is B31.3, the chemical plant and petroleum refinery code. Valid entries are B31.1, B31.3, B31.4, B31.4 Chapter IX, B31.5, B31.8, B31.8 Chapter VIII, B31.11, ASME-NC(Class 2), ASME-ND(Class 3), NAVY505, Z662, BS806, SWEDISH1, SWEDISH2, B31.1-1967, STOOMWEZEN, RCCM-C, RCCM-D, CODETI, Norwegian, FDBR, BS7159, UKOOA, IGE/TD/12, and DNV.

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Occasional Load Factor The default value of 0.0 tells CAESAR II to use the value that the active piping code recommends. B31.1 states that the calculated stress may exceed the maximum allowable stress from Appendix A, (Sh), by 15% if the event duration occurs less than 10% of any 24 hour operating period, and by 20% if the event duration occurs less than 1% of any 24 hour operating period. The default for B31.1 applications is 15%. If 20% is more suitable for the system being analyzed then this directive can be used to enter the 20%. B31.3 states, “The sum of the longitudinal stresses due to pressure, weight, and other sustained loadings (S1) and of the stresses produced by occasional loads such as wind or earthquake may be as much as 1.33 times the allowable stress given in Appendix A. Where the allowable stress value exceeds 2/3 of yield strength at temperature, the allowable stress value must be reduced as specified in Note 3 in 302.3.2.” The default for B31.3 applications is 33%. If this is too high for the material and temperature specified then a smaller occasional load factor can be input.

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Yield Stress Criterion The 132 column stress report produced by CAESAR II contains a value representative of the maximum stress state through the cross section, computed per the indicated yield criteria theory. CAESAR II can compute this maximum stress (note, this is not a Code stress) according to either Von Mises Theory or the Maximum Shear Theory. The selected stress is computed at four points along the axis normal to the plane of bending (outside top, inside top, inside bottom, outside bottom), and the maximum value is printed in the stress report. The equations used for each of these yield criteria are listed below. If the Von Mises Theory is used, CAESAR II computes the octahedral shear stress, which differs from the Von Mises stress by a constant factor. (For B31.4 Chapter IX, B31.8 Chapter VIII, and DnV this setting controls which equation is used to compute the "equivalent stress". For these three codes, the equations shown in the code are used to determine the yield criterion, not the standard mechanical stress equations shown below. These standard mechanical stress equations are used for the other codes addressed by CAESAR II. )

3D Maximum Shear Stress Intensity (Default) SI = Maximum of: S1OT - S3OT S1OB - S3OB Max(S1IT,RPS) - Min(S3IT,RPS) Max(S1IB,RPS) - Min(S3IB,RPS) Von Mises Stress (Octahedral) OCT = Maximum of: (S3OB2+S1OB2+(S3OB-S1OB)2)1/2 / 3.0 ((S3IB-RPS)2+(S3IB-S1IB)2+(RPS-S1IB)2)1/2 / 3.0 (S3OT2+S1OT2+(S1OT-S3OT)2)1/2 / 3.0 ((S3IT-RPS)2+(S3IT-S1IT)2+(RPS-S1IT)2)1/2 / 3.0 Where: S1OT=Maximum Principal Stress, Outside Top = (SLOT+HPSO)/2.0+(((SLOT-HPSO)/2.0)2+TSO2)1/2 S3OT=Minimum Principal Stress, Outside Top =(SLOT+HPSO)/2.0- (((SLOT-HPSO)/2.0)2+TSO2)

1/2

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S1IT=Maximum Principal Stress, Inside Top =(SLIT+HPSI)/2.0+(((SLIT-HPSI)/2.0)2+TSI2)

1/2

S3IT=Minimum Principal Stress, Inside Top =(SLIT+HPSI)/2.0- (((SLIT-HPSI)/2.0)2+TSI2)

1/2

S1OB=Maximum Principal Stress, Outside Top =(SLOB+HPSO)/2.0+ (((SLOB-HPSO)/2.0)2+TSO2)

1/2

S3OB=Minimum Principal Stress, Outside Bottom =(SLOB+HPSO)/2.0- (((SLOB-HPSO)/2.0)2+TSO2)

1/2

S1IB=Maximum Principal Stress, Inside Bottom =(SLIB+HPSI)/2.0+ (((SLIB-HPSI)/2.0)2+TSI2)

1/2

S3IB=Minimum Principal Stress, Inside Bottom =(SLIB+HPSI)/2.0- (((SLIB-HPSI)/2.0)2+TSI2)

1/2

RPS=Radial Pressure Stress, Inside HPSI=Hoop Pressure Stress (Inside, from Lame’s Equation) HPSO=Hoop Pressure Stress (Outside, from Lame’s Equation) SLOT=Longitudinal Stress, Outside Top SLIT=Longitudinal Stress, Inside Top SLOB=Longitudinal Stress, Outside Bottom SLIB=Longitudinal Stress, Inside Bottom TSI=Torsional Stress, Inside TSO=Torsional Stress, Outside

B31.3 Sustained Case SIF Factor B31.3 Code Interpretation 1-34 dated February 23, 1981 File: 1470-1 states that for sustained and occasional loads an SIF of 0.75i, but not less than 1.0 may be used. This setup directive allows the user to enter his/her own coefficient. The default is 1.0. To comply with this interpretation the user would enter 0.75. B31.3 Code Interpretation 6-03 dated December 14, 1987 permitted users to ignore the stress intensification for sustained and occasional loads.To comply with this interpretation, the user would enter 0.0.

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B31.3 Welding and Contour Insert Tees Meet B16.9 This flag controls the "assumption" that the geometry of B31.3 welding and contour insert tees (sweepolets) meet the dimensional requirements of the code, and can be classified as B16.9 tees. The default setting for this directive is "NO", which causes the program to use a flexibility characteristic of 3.1*T/r, as per the A01 addendum. Selecting this checkbox, allows the program to assume that the fitting geometry meets the requirements of Note 11, introduced in the A01 addendum, and a flexibility characteristic of 4.4*T/r will be used. Note: In order to match runs made with CAESAR II prior to Version 4.40, this checkbox must be selected. Prior to Version 4.40, CAESAR II always used a flexibility characteristic of 4.4*T/r.

Allow User's SIF at Bend This feature was added for those users that wished to change the stress intensification factor for bends. Previously this was not permitted, and the code defined SIF was always used. If the user enables this directive, he may override the code’s calculated SIF for bends. The user entered SIF acts over the entire bend curvature and must be specified at the “TO” end of the bend element. The default is off.

Use WRC329 This directive activates the WRC329 guidelines for all intersections, (not just for reduced intersections). The recommendations made by Rodabaugh in section 5.0 of WRC329 will be followed exactly in making the stress calculations for intersections. Every attempt has been made to improve the stress calculations for all codes, not just the four discussed in Rodabaugh’s paper. Users not employing either B31.1, B31.3 or the ASME NC or ND codes, and who wish to use WRC329 are encouraged to contact COADE for additional information. Throughout this document WRC330 and WRC329 are used synonymously (330 was the draft version of 329). When finally published, the official WRC designation was 329.

Use Schneider This directive activates the Schneider reduced intersection assumptions. It was because of observations by Schneider that much of the work on WRC 329 was started. Schneider pointed out that the code SIFs could be in error when the d/D ratio at the intersection was less than 1.0 and greater than 0.5. In this d/D range the SIFs could be in error by a factor as high as 2.0. Using the Schneider option in CAESAR II results in a multiplication of the out of plane branch stress intensification by a number between 1 and 2 when the d/D ratio for the intersection is between 0.5 and 1.0. For B31.1 and other codes that do not differentiate between in and out-of-plane SIFs the multiplication will be used for the single stress intensification given.

All Cases Corroded A recent version of the B31.3 piping code mentioned reducing the section modulus for sustained or occasional stress calculations by the reduction in wall thickness due to corrosion. Several users have interpreted this to mean that the reduced section modulus should be used for all stress calculations, including expansion. This directive allows those users to apply this conservative interpretation of the code. Enabling All Cases Corroded causes CAESAR II to use the corroded section modulus for the calculation of all stress types. This method is recommended as conservative, and probably more realistic as corrosion can significantly affect fatigue life, i.e., expansion. Disabling this directive causes CAESAR II to strictly follow the piping code recommendations, i.e. depending on the active piping code, some load cases will consider corrosion and some will not.

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Liberal Expansion Stress Allowable Activate this check box in order to cause CAESAR II to default new jobs to use the “Liberal Expansion Stress Allowable” – to add the difference between the hot allowable stress and the sustained stress to the allowable expansion stress range (if permitted by the particular code in use). Deactivating this option causes new jobs to default to not using this allowable.

WRC 329 Allows the user to use the recommendations of WRC 329 for reduced intersections. A reduced intersection is any intersection where the d/D ratio is less than 0.975. The WRC 329 recommendations result in more conservative stress calculations in some instances and less conservative stress calculations in others. In all cases the WRC 329 values should be more accurate, and more truly in-line with the respective codes intent.

Base Hoop Stress On ( ID/OD/Mean/Lamés ) This directive is used to indicate how the value of hoop stress should be calculated. The default is to use the ID of the pipe. Most piping codes consider the effects of pressure in the longitudinal component of the CODE stress. Usually, the value of the hoop stress has no bearing on the CODE stress, so changing this directive does not affect the acceptability of the piping system. If desired, the user may change the way CAESAR II computes the hoop stress value. This directive has the following options: ID—Hoop stress is computed according to Pd/2t where “d” is the internal diameter of the pipe. OD—Hoop stress is computed according to Pd/2t where “d” is the outer diameter of the pipe. Mean—Hoop stress is computed according to Pd/2t where “d” is the average or mean diameter of the pipe. Lamés—Hoop stress is computed according to Lamés equation, Ri2 ) and varies through the wall as a function of R.

= P ( Ri2 + Ri2 * Ro2 / R2 ) / ( Ro2 -

Use PD/4t Enabling this directive causes CAESAR II to use the simplified form of the longitudinal stress term when computing sustained stresses. Some codes permit this simplified form when the pipe wall thickness is thin. This option is used most often when users are comparing CAESAR II results to those from an older pipe stress program. The more comprehensive calculation, i.e. the Default, is recommended.

Add F/A in Stresses Determines whether or not the axial stress term is included in the code stress computation. Setting this directive to Default causes CAESAR II to use whatever the currently active piping code recommends. Only the B31.3-type piping codes (i.e. codes where the sustained stress equation is not explicitly given) have the F/A stresses included in the sustained and occasional stress equations. The B31.1-type codes do not include the F/A stresses because the equations given explicitly in the code do not include it. The F/A stresses discussed here are not due to longitudinal pressure. These are the F/A stresses due to structural loads in the piping system itself.

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Add Torsion in SL Stress Some piping codes include torsion in the sustained and occasional stresses by explicitly including it in the stress equation (i.e. B31.1), and some don’t include torsion in the sustained and occasional stresses by implicitly calling for “longitudinal stresses” only (i.e. B31.3). Setting the Add Torsion in SL Stress directive to Yes forces CAESAR II to include the torsion term in those codes that don’t include it already by default. Setting this directive to Default causes CAESAR II to use whatever the currently active piping code implies. In a sustained stress analysis of a very hot piping system subject to creep, it is recommended that the user include torsion in the sustained stress calculation via this parameter in the setup file.

Stress Stiffening Due to Pressure This flag instructs the program to include pressure stiffening effects on straight pipes. The options for this flag are:

0 - no stiffening of straight pipes due to pressure 1 - elemental stiffening using Pressure #1 2 - elemental stiffening using Pressure #2

Note, this option modifies the element's stiffness matrix.

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Reduced Intersection Available options are B31.1(Pre 1980), B31.1(Post 1980), WRC329, ASME SEC III, and Schneider:

B31.1 (Pre 1980) Allows the B31.1 code user to have the pre-1980 code rules used for reduced intersection. These rules didnot define a separate branch SIF for the reduced branch end. The branch stress intensification factor will be the same as the header stress intensification factor regardless of the branch-to-header diameter ratio.

B31.1 (Post 1980) Allows the B31.1 code user to employ the post-1980 code rules for reduced intersections. The reduced intersection SIF equations in B31.1 from 1980 through 1989 generated unnecessarily high SIFs because of a mistake made in the implementation. (This is as per WRC329.) For this reason many users opted for the “Pre 1980” B31.1 SIF calculation discussed above. CAESAR II corrects this mistake by the automatic activation of the flag: B31.1 Reduced Z Fix = On. Users can vary the status of this flag in the CAESAR II setup file to generate any interpretation of B31.1 desired. The default for a new job is for B31.1(Post 1980) and for the B31.1 Reduced Z Fix = On. The No RFT/WLT in Reduced Fitting SIFs flag also affects the SIF calculations at reduced intersections and is also available in this release.

WRC 329 Allows the user to use the recommendations of WRC329 for reduced intersections. A reduced intersection is any intersection where the d/D ratio is less than 0.975. The WRC329 recommendations result in more conservative stress calculations in some instances and less conservative stress calculations in others. In all cases the WRC329 values should be more accurate, and more truly in-line with the respective codes intent.

ASME Sect. III Allows the user to use the 1985 ASME Section III NC and ND rules for reduced intersections.

Schneider Activates the Schneider reduced intersection stress intensification factor multiplication. Has the same effect as the Use Schneider option.

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Class 1 Branch Flexibility Activates the Class 1 flexibility calculations. The appearance of this parameter in the setup file will completely change the modeling of intersections in the analysis. For intersections not satisfying the reduced branch rules that d/D 0.5 and that D/T 100, the branch will start at the surface of the header pipe. A perfectly rigid junction between the centerline of the header and surface will be formed automatically by CAESAR II using the element offset calculations. SIFs act at the surface point for the branch. When the reduced branch rules are satisfied, the local flexibility of the header is also inserted at this surface point. Intersections not satisfying the reduced intersection rules will be “stiffer” and carry more load, while intersections satisfying the reduced intersection rules will be more flexible and will carry less load. All changes to the model are completely transparent to the user. In systems where the intersection flexibility is a major component of the overall system stiffness, the user is urged to run the analysis both with and without the Class 1 Branch Flexibility active to determine the effect this modeling on the analysis. For more technical discussion, refer to Class 1 Branch Flexibilities (on page 14).

B31.1 Reduced Z Fix This directive is used in conjunction with B31.1, and makes the correction to the reduced branch stress calculation that existed in the 1980 through 1989 versions of B31.1. This error was corrected in the 1989 version of B31.1, and the B31.1 Reduced Z Fix is on by default in CAESAR II.

Schneider Activates the Schneider reduced intersection stress intensification factor multiplication. Has the same effect as the Use Schneider option.

No RFT/WLT in Reduced Fitting SIFs There has been considerable concern involving the SIFs for reduced fittings. Part of the discussion centers around just what should be considered a reduced fitting. The CAESAR II default is to assume that welding tees and reinforced fabricated tees are covered by the reduced fitting expressions, even though the reduced fitting expressions do not explicitly cover these intersection types. Users wishing to leave welding tees and reinforced tees out of this definition should enable this directive.

Apply B31.8 Note 2 The B31.8 piping code defines both "in-plane" and "out -of -plane" SIF values. The notes to Appendix E, B31.8 states that a more conservative approach can be taken, by using the "out-of-plane" SIF value for the "in-plane" value (Note 2). This directive controls whether or not this more conservative approach is used. Prior to Version 4.30, CAESAR II always applied Note 2, the more conservative approach, and there was no way to alter this behavior. The user can control (through the use of this directive) whether or not Note 2 is implemented. The default behavior is to use the two different SIF values and not employ Note 2.

Pressure Variation in Expansion Cases This directive controls whether or not any pressure variation (between the referenced load cases) will appear in the resulting expansion load case.

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Geometry Directives

Geometry Directives Configuration Settings

Connect Geometry Through Cnodes Restraints, flexible nozzles, and spring hangers may be defined with connecting nodes. By default CAESAR II ignores the position of the restraint node and the connecting node. They may be at the same point or they may be hundreds of feet apart. This directive allows the user to insist that each restraint, nozzle, or hanger exists at the same point in space as its connecting node. In many cases, enabling this option will cause “plot-wise” disconnected parts of the system to be re-connected and to appear “as expected” in both input and output plots.

Auto Node Number Increment This directive sets the value for the Automatic Node Numbering routine. Any non-zero, positive value in this data cell is used to automatically assume the “TO NODE” value on the piping input spreadsheets. The new (TO) node number is determined as: “To Node” = “From Node” + Auto Node Number Increment. If this value is set to 0.0, automatic node numbering is disabled.

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Z-Axis Vertical By default CAESAR II assumes the Y axis is vertical with the X and Z axes in the horizontal plane. If desired, the Z axis can be made vertical by checking this box. In this case, the X and Y axes will be in the horizontal plane.

Minimum Allowed Bend Angle Very small angles, short radius bends can cause numerical problems during solution. When the user has a reasonable radius and a small angle there are usually no problems. However, if the small angle bend is grossly small compared to the surrounding elements then the bend should probably not be used and a different modeling approach employed. Enabling this directive allows the user to reset the minimum angle CAESAR II will accept for a bend angle. The default is 5.0 degrees.

Maximum Allowed Bend Angle Very large angles, short radius bends can cause numerical problems during solution. When the user has a reasonable radius and a large angle there are usually no problems. However, if the large angle bend plots compared reasonably well to the surrounding elements then the bend can probably be used without difficulty. Well-proportioned bends up to 135 degrees have been tested without a problem. Enabling this directive allows the user to reset the maximum angle CAESAR II will accept for a bend. The default is 95 degrees.

Bend Length Attachment Percent Whenever the element leaving the tangent intersection of a bend is within (n)% of the bend radius on either side of the weldline, CAESAR II inserts an element from the bend weldline to the “TO” node of the element leaving the bend. The inserted element has a length equal to exactly (n)% of the bend radius. The user may adjust this percentage to reduce the error due to the inserted element, however, the length tolerance for elements leaving the bend will also be reduced. To obtain more accurate results the user must include less “slop” in the system dimensions around bends. The default attachment is 1.0 percent.

Minimum Angle to Adjacent Bend Nodes on a bend curvature that are too close together can cause numerical problems during solution. Where the radius of the bend is large, such as in a cross country pipeline, it is not uncommon to find nodes on a bend curvature closer than 5 degrees. In these situations the user may enable this directive to change the CAESAR II error checking tolerance for the “closeness” of points on the bend curvature. The default is 5.0 degrees.

Loop Closure Tolerance The loop closure tolerance used by CAESAR II for error checking can be set interactively by the user for each job analyzed, or the user can enter the desired loop closure tolerance via this directive and override without distraction the program default value of 1.0 in. See the following section for a discussion of the CAESAR II units file.

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Horizontal Thermal Bowing Tolerance This directive enables the user to specify the maximum slope of a straight pipe element for which thermal bowing effects will be considered. Thermal bowing is usually associated with fluid carrying horizontal pipes in which the fluid does not fill the cross section. In these cases, there is a temperature differential across the cross section. This directive allows the user to define the interpretation of “horizontal.” By default, the program uses a value of 0.0001 as the horizontal threshold value. If a pipe element’s pitch is less than this tolerance, the element is considered to be horizontal, and thermal bowing loads can be applied to it. An element’s pitch is computed from: PITCH = | DY | / ( DX2 + DY2 + DZ2 )1/2

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Plot Colors

Plot Colors Configuration Settings

OPENGL Switch By default the 3D Hoops graphics engine uses the OPENGL drivers. On some machines with older graphics cards, or older graphics drivers, OPENGL does not perform well. Unchecking this checkbox instructs the CAESAR II graphics engine to use the alternate Microsoft drivers, instead of the OPENGL drivers.

Pipes Enter the color for the center-line and volume plots of pipe elements. Excludes valves, other rigids and expansion joints.

Nodes Enter the color for the node numbers.

Rigids/Bends Enter the color for the rigid elements and for bend highlighting in the input plot.

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Hangers/Nozzles Enter the color for the hanger and nozzle symbols that are displayed on the input plot.

Structure Enter the color that the structural elements should be plotted in. The color selected should contrast with the color entered for the Pipes.

Background Enter the color for the plot background. The user should be careful setting this parameter because all other colors need to coordinate with the background color selected.

Axes Enter the color of the plot axes that appear in the bottom left corner of the screen.

Labels Enter the color for the geometry labels exclusive of the node numbers. Examples are, Diameter, Thickness, Length, Plot Labeling.

Highlights Enter the color for the input level plot highlight. The color selected should contrast with the color entered for the Pipes.

Displaced Shape Enter the color for the displaced shape overlay. The color selected should contrast with the color entered for the Pipes.

Stress Level 1 Enter the stress value that defines the lower limit cutoff.

Stress Level 2 Enter the stress value that defines the second lowest stress color-plot limit.

Stress Level 3 Enter the stress value that defines the third lowest stress color-plot limit.

Stress Level 4 Enter the stress value that defines the fourth lowest stress color-plot limit.

Stress Level 5 Enter the stress value that defines the upper limit cutoff.

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Stress < Level 1 Enter the color for that portion of the pipe that has a stress lower than Stress Level 1.

Stress > Level 1 Enter the color for that portion of the pipe that has a stress greater than Stress Level 1 and less than Stress Level 2.

Stress > Level 2 Enter the color for that portion of the pipe that has a stress greater than Stress Level 2 and less than Stress Level 3.

Stress > Level 3 Enter the color for that portion of the pipe that has a stress greater than Stress Level 3 and less than Stress Level 4.

Stress > Level 4 Enter the color for that portion of the pipe that has a stress greater that Stress Level 4 and less than Stress Level 5.

Stress > Level 5 Enter the color for the portion of the pipe element that has a stress greater than Stress Level 5. The color of an element from one end to the other varies as the stress varies.

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FRP Pipe Properties

FRP Properties Configuration Settings

Use FRP SIF By default, when FRP pipe is selected (Material #20), CAESAR II sets the fitting SIF to 2.3. Some users have requested that the standard “code” SIF be used, others have requested the ability to specify this value manually. By disabling this directive, the standard “code” SIF equations will be applied to all FRP fittings. This also allows manual specification of these values by the user. If the BS 7159 or UKOOA Codes are in effect, code SIFs will always be used, regardless of the setting of this directive.

Use FRP Flexibilities By default, when FRP pipe is selected (Material #20), CAESAR II sets the fitting flexibility factor to 1.0. Some users have requested that the standard “code” flexibility factor be used. By disabling this directive, the standard “code” flexibility factor equations will be applied to all FRP fittings. If the BS 7159 or UKOOA Codes are in effect, code flexibility factors will always be used, regardless of the setting of this directive.

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FRP Property Data File Standard FRP material properties may be read in from files. The user may select the available files. Once selected, the program will give the user the option of reading in from that file. Users may create FRP material files as text files with the .frp extension; these files should be stored in the CAESAR\SYSTEM sub-directory. The format of the files must adhere to the following format:

Sample FRP Data File

Note: The data lines must follow exactly the order shown above. The four data lines defining the UKOOA envelope are intended for future use and may be omitted.

BS 7159 Pressure Stiffening The BS 7159 code explicitly requires that the effect of pressure stiffening on the bend SIFs be calculated using the Design Strain (this is based upon the assumption that the FRP piping is fully pressurized to its design limit). This is CAESAR II’s default method. When the piping is pressurized to a value much lower than its design pressure, it may be more accurate to calculate pressure stiffening based on the Actual Pressure stress, rather than its design strain. Note that this alternative method is a deviation from the explicit instructions of the BS 7159 code.

FRP Laminate Type The default Laminate Type (as defined in the BS 7159 code) of the fiberglass reinforced plastic pipe used should be entered. Valid laminatetypes are Chopped strand mat (CSM) and woven roving (WR) construction with internal and external surface tissue reinforced layer. Chopped strand mat (CSM) and multi-filament roving construction with internal and external surface tissue reinforced layer. All chopped strand mat (CSM) construction with internal and external surface tissue reinforced layer. This entry is used in order to calculate the flexibility and stress intensity factors of bends; therefore this default entry may be overridden using the Type field on the bend auxiliary spreadsheets.

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CAESAR II Technical Reference Manual

Exclude f2 from UKOOA Bending Stress Some sources, such as Shell's DEP 31.40.10.19-Gen. (December 1998) and ISO/DIS 14692 suggest that, when using the UKOOA code, the axial bending stress should not be multiplied by the Part Factor f2 (the System Factor of Safety) prior to combination with the longitudinal pressure stress. Users wishing to modify the UKOOA requirements in this way should enable this check box. Users wishing to use UKOOA exactly as written should disable this check box.

FRP Pipe Density

Weight of the pipe material on a per unit volume basis. This field is used to set the default weight density of FRP materials in the piping input module.

FRP Alpha (e-06) In this field, the thermal expansion coefficient for the fiberglass reinforced plastic pipe used (multiplied by 1,000,000) should be entered. For example, if the value is: 8.5E-6 in/in/deg, then the user would enter 8.5 in this field. The exponent (E-6) is implied. If a single expansion coefficient is too limiting for the user’s application, the actual thermal expansion may always be calculated at temperature in inches per inch (or mm per mm) and entered directly into the Temperature field on the Pipe spreadsheet.

FRP Modulus of Elasticity Axial elastic modulus of Fiberglass Reinforced Plastic pipe. This is the default value used to set the data in the input processor. The user may override this value in the input when necessary.

Ratio Shear Mod:Emod In this field, the ratio of the shear modulus to the modulus of elasticity (in the axial direction) of the fiberglass reinforced plastic pipe used should be entered. For example, if the material modulus of elasticity (axial) is 3.2E6 psi, and the shear modulus is 8.0E5 psi, the ratio of these two, 0.25, should be entered here.

Axial Strain:Hoop Stress (Ea/Eh*Vh/a) The product of the ratio of the axial to the hoop elastic modulus and Poisson's ratio which relates the strain in the axial direction to a stress in the hoop direction. Ea - Elastic modulus in the axial direction. Eh - Elastic modulus in the hoop direction. Vh/a - Poissons ratio relating the strain in the axial direction due to a stress in the hoop direction.

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Database Definitions

Database Definitions Configuration Settings

Structural Database This directive specifies which database file is to be used to acquire the structural steel shape labels and cross section properties from. The structural databases provided include AISC 1977, AISC 1989, German 1991, South African 1991, Korean 1990, Australian 1990, and United Kingdom.

Piping Size Specification (ANSI/JIS/DIN/BS) By default, CAESAR II uses the ANSI pipe size and schedule tables in the input processor. Users may optionally select the standard tables of another piping specification using this directive. The available tables are American National Standard (ANSI) Japanese Industrial Standard (JIS) German Standard (DIN)

Valves and Flanges This directive enables the user to specify which Valve/Flange database should be referenced by CAESAR II during subsequent input sessions. The databases provided include the following: a generic database, the Crane database, a database (generic) without attached flanges, and the CADWorx/Pipe database.

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Expansion Joints This directive enables the user to specify which Expansion Joint database should be referenced by CAESAR II during subsequent input sessions. The databases provided include Pathway, Senior Flexonics, IWK, and Piping Technology.

Units File Name This directive allows the user to scroll through the available units files and select one to activate. Since the CAESAR.CFG file is written to the local data directory, different data directories can be configured to reference different units files. Units files are searched for first in the local data directory, and then in the “active SYSTEM” directory. The active units file is used for new job creation and all output generation.

Load Case Template This directive allows the user to scroll through the available load case templates and select the one to be active. Since the CAESAR.CFG file is written to the local data directory, different data directories can be configured to reference different template files. Template files are searched for first in the local data directory, and then in the "active SYSTEM" directory. The active template file is used to "recommend" load cases.

System Directory Name This directive enables a user to select which “SYSTEM” directory is used by CAESAR II. All of the various system directories contain formatting files, units files, text files, and other “user configurable” data files. Some of these formatting files are language specific or Code specific. Therefore, users may want to switch between system directories depending on the current job. The directive allows the user to scroll through the available system directories and select one to be ACTIVE. Since the CAESAR.CFG file is written to the local data directory, different data directories can be configured to reference different system directories. All system directory names must be of the form: SYSTEM.??? where the .??? is a three character suffix identifying the directory. Users can create system directories as needed, following this required naming convention. The CAESAR II distribution diskettes contain language files for English, French, German, and Spanish. These formatting files can be installed in separate system directories, with an appropriate suffix, to allow switching between languages. Note that there must be a primary system directory, named system, for the program to place accounting, version, and diagnostic files that it creates during execution. The secondary system directories are only referenced for llanguage and formatting files.

Default Spring Hanger Table This directive is used to set the value of the default spring hanger table, referenced during the spring hanger design stage of the solution. CAESAR II includes tables from more than 20 different vendors.

Enable Data Export to ODBC-Compliant Databases This directive turns on the capability to create ODBC-compliant databases for static output.

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Append Reruns to Existing Data The default of NO (unchecked) causes a rerun to overwrite data from previous runs in the ODBC database. Turning this directive on (checked) causes a rerun to add new data to the database, thus storing multiple runs of the same job in the database.

ODBC Compliant Database Name This field contains the name of the ODBC project database. All jobs run in this data directory will write their output to the database specified here.

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Miscellaneous

Miscellaneous Configuration Settings

Output Table of Contents This directive allows the user to control the generation of a Table of Contents, normally produced after a static or a dynamic output session. By default this directive is turned on, which causes the output processors to generate a Table of Contents upon exit. Turning this directive off disables the generation of the Table of Contents.

Output Reports by Load Case By default, CAESAR II generates output reports sorted by load case. As an option, this directive may be turned off, which will cause the output reports to be sorted by type. For reports by type, all displacement reports will be generated, then all restraint reports, then all force reports, etc.

Displacement Reports Sorted by Nodes By default CAESAR II sorts the nodes in ascending order during the force/stress computations. This produces a displacement output report in which the nodes are ordered in increasing magnitude. This directive can be turned off to disable this nodal sort. The resulting displacement reports will be produced in the order the nodes were entered during model building.

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Time History Animation This directive allows the user to disable the creation of the file used to animate the “time history” displacement of the piping system. By default this directive is turned on, which instructs CAESAR II to generate a file of displacements, <jobname>.XYT, for every time step. This file is used in subsequent interactive animation sessions by the user. Note, however, that the size of this file is dependent on the size of the model and the number of time steps analyzed. It may therefore be advantageous from a “disk usage” point of view not to create this file. To instruct CAESAR II not to create this file, turn this setting off.

Dynamic Example Input Text This directive allows the user to control how much example text is placed in “new” dynamic input files. By default, CAESAR II places example text and spectrum definitions in the input stream of “new” dynamic input files. Once a user is familiar with the input, this example text may be undesirable. This directive allows the user to vary how much of this example text is incorporated in the input. MAX - This setting is the default and instructs CAESAR II to place all of the examples and spectrum definitions in the input stream of “new” dynamic input files. NONE -This directive eliminates all of the example text and all of the built in spectrum definitions. This setting is intended for experienced users. SPEC -This setting eliminates all of the example text, but leaves the predefined spectrum definition. This means that the built in spectrum definitions (El Centro etc.) will still be defined, and available for use.

Memory Allocated This setting modifies the Windows registry to increase the amount of RAM available to CAESAR II. Setting this directive to a number greater than the available RAM will cause Windows to use Virtual Memory (Hard Disk Space to be used as RAM) to be used. This may slow the program, however, and is normally recommended only for very large piping models.

User ID When more than one workstation attempts to the CAESAR II data in the same directory at the same time it causes a corruption of the control file in the data directory, which may cause abnormal program execution. Therefore, in situations where there may be more than one concurrent user running CAESAR II in a given data directory each user (or more exactly, each workstation) should enter a three-character User ID in this field. This creates a separate control file for each User ID to allow simultaneous access of the CAESAR II data within the same directory. Note: user.

This User ID is not a password and is specific to the computer requiring access and not to the

Disable "File Open" Graphic Thumbnail This directive disables the graphic thumbnail plot in the File Open dialog boxes. The graphics thumbnail plots a small image of the model as a single line drawing. On some slower, memory limited processors, or when scanning very large models, this thumbnail graphic may take a few seconds to plot the model. To prevent this delay check this box to turn off the graphics.

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Disable Undo/Redo Ability It may be desirable on some installations to disable the UNDO/REDO feature of the input module. With UNDO/REDO enabled, CAESAR II can process a job approximately one-half the size of that which can be processed when UNDO/REDO is disabled (for similar memory settings). Likewise, with UNDO/REDO enabled, the input module speed may be reduced.

Enable Autosave When this option is checked, CAESAR II will automatically save the piping input at specified intervals.

Autosave Time Interval This value (in minutes) is the time interval used to perform the auto-save function. Autosave will be initiated every "X" minutes, where the value of "X" is specified in this edit box.

Prompted Autosave When this option is checked, CAESAR II will prompt the user, at the specified time interval, to save the input. If this option is not checked, the input will be saved automatically at the specified time intervals (assuming autosave is enabled).

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Set/Change Password The Password button provides the user with the option of providing a password protection scheme for the configuration file. By setting a password on the primary configuration file (done by setting the default data directory to the CAESAR II program directory), a corporate standard can be enforced throughout the network. Subsequent use of the configuration module in other data directories will allow modification only of display or other environment directives (i.e., those that do not affect calculated results). When this button is clicked, a secondary window is displayed with four possible selections: New Password Access Protected Data Change Password Remove Password

Access Protected Data This option is accessible once a password exists. Assuming the correct password is given for access, the user is then allowed to modify “protected” directives. The use of this option is not necessary if there is no previously specified password. If no password has been set, all directives can be modified by the user.

New Password Once a password has been entered, the user has the ability to change configuration settings from the program directory, or alter or remove the password. When entering a new password the user is prompted for the new password a second time to ensure the password was typed as expected by the user the first time.

Change Password The current password may be changed at any time by a user who has authorization (he/she must enter the correct existing password for access to this directive). Once a password has been set, all computation controls, stress directives, and any other directives which could affect the CAESAR II computations are disabled and cannot be changed by the user. All protected directive labels, edit boxes, and default buttons are grayed out when disabled.

Remove Password The current password may be removed at any time by a user with authorization to do so (he/she must enter the correct existing password for access to this directive). Once a password has been removed, all directives in CONFIGURE/SETUP are modifiable by the user from any directory where he/she has read/write access rights.

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Units File Operations The active units file as specified in the configuration file is used in conjunction with all new input files and all existing output files in the given data directory. The units file specified in the configuration file will not modify the units in an existing CAESAR II input file Convert Input to New Units.

Make Units File

The user may create a custom units file or review an existing units file by choosing TOOLS /MAKE UNITS FILE from the CAESAR II Main Menu. An explanation of each input field and button under this option follows.

Review Existing Units File

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Make Units File Dialog

Clicking the Review Existing Units File button highlights a list box to the right that contains all existing units files located in both the data directory and the program directory. Choose the units file to review from the list, then click the View/Edit File button to proceed. A window will display (see below) containing all CAESAR II dimensional items, their internal units, the conversion factor between the internal units and the user-specified units, and the user’s units.

Review Existing Units Dialog

Create a New Units File

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Units Maintenance

Clicking the Create a New Units File button creates a new units file and activates the next two items described below. When all items are completed choose the View/Edit File button to proceed. A window will appear in which the entries for the user's units and the conversion factor can be edited. If the userdefined units for a given item exists in the list then there is no need to choose a conversion factor as it will be updated automatically. If a new set of units is desired (miles in the length category for instance) then the user may type in (or select from the drop down list) the new unit name (mi.) and the new conversion factor (.00001578 in this example).

Create New Units Dialog

Existing File to Start From In CAESAR II a new units file is created by using an existing units file as a template. Choose an existing units file from the list. It is simplest to choose a file that has many units in common with the file to be created.

New Units File Name A unique file name must be entered here without the extension.

View/Edit File Click this button to proceed once all activated lists on the Create New Units dialog have been completed.

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Convert Input to New Units

The user may convert an existing input file to a new set of units by choosing TOOLS / CONVERT INPUT TO NEW UNITS from the CAESAR II Main Menu. A window will be created that contains the following three input fields:

Units File Conversion Dialog

Name of the Input File to Convert Type the full path name followed by the input file name (including the ._a extension) to be converted. The Browse button to the right of this text box may be used to choose the appropriate input file.

Name of the Units File to Use Select the name of the appropriate units file from the list provided.

Name of the Converted File Type the full path name followed by the input file name that corresponds to the new input file. Caution: Clicking the Browse button here and picking an existing ._a file the converted file will overwrite the existing ._a file chosen from the list.

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Material Database

CAESAR II provides a material database (accessed with TOOL/MATERIAL DATABASE from the MAIN MENU listing physical properties and code-dependent allowable stresses of more than 300 materials. These materials can be edited and additional materials can be added to the database by the user. Note: It is incumbent upon the user to check material allowables and other physical property data for the particular code being used. While COADE attempts to keep the material database up-to-date the codes are subject to change frequently and the accuracy of the database is not guaranteed. Below is an explanation of the input fields for the Material Database.

Material - Add To add a new material spreadsheet to the database. This command saves any data currently shown on the spreadsheet and clears the spreadsheet for a new entry. At least a material number and code must be given for the data to be saved.

Material - Delete This operation deletes the entire material spreadsheet from the database. The user may choose the spreadsheet to delete from the list which contains only user-defined database spreadsheets. The user cannot delete the material database spreadsheets supplied with the CAESAR II program.

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Material - Edit To edit an existing material spreadsheet in the database. A window will appear from which the user must either type the name of the material or pick the material from the list. The piping code ID on the right side corresponds to the piping code ID on the piping input spreadsheet when allowables are chosen.

Material Database Editor Displaying Data for A106-B

Number Enter a number by which the material is to be referenced. The number must be between 101 and 699 inclusive and should not already be a reference for another material.

Name Enter the material name as listed in the applicable code.

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Applicable Piping Code Enter the CAESAR II piping code number for the material. A list of the piping code numbers for the various codes are listed below. ALL

B31.5

NAVY 505

Stoomwezen

FDBR

B31.1

B31.8

CAN Z662

RCC-M C

BS 7159

B31.1 1967

B31.11

BS 806

RCC-M D

UKOOA

B31.3

ASME NC

Swedish 1

CODETI

IGE/TD/12

B31.4

ASME ND

Swedish 2

Norwegian TBK-6

DNV

Eff, Cf, z This factor is necessary for various piping codes as defined below: STOOMWEZEN - The cyclic reduction factor, referred to in the code as Cf. NORWEGIAN - This is the circumferential weld strength factor, “z”. If not entered, it defaults to 1.0. BS 7159 - This field is the ratio of the design stress sd, in the circumferential (hoop) direction to the design stress in the longitudinal direction. Since design stress is defined in Sec. 4.3 of the code as: dÆ

=

d

* ElamÆ, sd x = d * Elamx

and design strain should be the same for both directions, this entry will also be the ratio of the moduli of elasticity ElamÆ (hoop) to Elamx (longitudinal). If left blank, a value of 1.0 will be used.

Density Enter the density of the material.

Minimum Temperature Curve (A-D) As defined by B31.3 (Section 323.2.2), some carbon steels are limited to a “minimum metal” temperature as shown in Figure 323.2.2. This cell is used to specify which curve should be used to check this material. If this code section is applicable, specify either A, B, C, or D. If this code section is not applicable, leave this cell blank. Note that this information is not currently used by CAESAR II.

FAC A factor necessary for various piping codes as defined below: Stoomwezen—This value should be either 0.44 or 0.5 and is used in computing the equilibrium stresses as discussed in Section 5.2 of the code. The value of 0.5 can be used for steel if the design and fabrication are such that stress peaks are avoided. Norwegian (units: 106) Material ultimate tensile strength at room temperature “Rm”. If not entered, this factor is not considered to control the expansion stress allowable.

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Poisson's Ratio For Metals only. Enter the value to be used for Poisson’s Ratio for this material.

Temperature In this field enter the temperatures corresponding to the database values you will add to the right. In the database supplied with CAESAR II all temperatures are in 100°F increments. Note that some of the codes list physical property values in 50°F increments, therefore small discrepancies may occur between CAESAR II and a given code because of the interpolation of data.

Exp. Coeff. Enter the expansion coefficient at the corresponding temperature. This coefficient must be multiplied by 106 F prior to being input here. (ex. An expansion coefficient of 1.2 x 10-5 in/in/F would be input as 12).

Allowable Stress Input the code allowable stress corresponding to the temperature to the left.

Elastic Modulus This is the Modulus of Elasticity corresponding to the temperature to the left.

Yield Stress This is the Yield Stress corresponding to the temperature to the left.

Ult Tensile Stress BS 806—Mean Stress to Failure for design life at temperature Swedish Method 1—Creep Rupture Stress at temperature. Stoomwezen—Rrg average creep stress to produce 1% permanent set after 100,000 hours at temperature (vm). IGE/TD/12 - Ultimate Tensile Strength Norwegian - (UNITS: lb./sq.in.) Material ultimate tensile strength at room temperature "Rm". If not entered, this factor is not considered to control the expansion stress allowable.

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CHAPTER 3

Piping Screen Reference This chapter illustrates how to enter job parameters through the program's menus, fields, and commands.

In This Chapter Piping Spreadsheet Data..............................................................2 Auxiliary Fields - Component Information .................................14 Auxiliary Fields - Boundary Conditions......................................31 Nozzles........................................................................................48 Auxiliary Fields - Imposed Loads ...............................................58 Auxiliary Fields - Piping Code Data ...........................................62 Available Commands ..................................................................79

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Piping Spreadsheet Data

Help Screens and Units The question mark key or the function key if pressed while in any of the input data cells, will produce interactive help text for that particular input item. Additionally, while resting the cursor on a field, a tool tip indicating the current units will appear.

From The FROM NODE number defines the starting end of the element. Node numbers must be numeric, ranging from 1 to 32000. Normally, the FROM NODE number is “duplicated forward” by CAESAR II from the preceding element. The node numbers may be changed by the user, who should take care not to use the same node number more than once in the model.

To The TO NODE number defines the end of the current element. Node numbers must be numeric, ranging from 1 to 32,000. The node numbers may be changed by the user, who should take care not to use the same node number more than once in the model.

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Name The Name check box is used to assign non-numeric names to node points. Double-clicking this check box activates an auxiliary spreadsheet where names, of up to 10 characters, can be assigned to the From and/or To nodes. These names will show up in place of the node numbers in graphic plots and reports (possibly truncated in 80 column reports).

DX Delta X (DX) defines the element's projected length along the global X direction. CAESAR II accepts [compound length]—[length]—[fraction] formats (such as feet - inch - fraction or meter - decimal - centimeters) as valid input values in most cells. Simple forms of addition, multiplication, and division may be used as well as exponential format. Enter the DISTANCE between the "TO" and the "FROM" node along the direction specified.

DY Delta Y (DY) defines the element's projected length along the global Y direction. CAESAR II accepts [compound length]—[length]—[fraction] formats (such as feet - inch - fraction or meter - decimal - centimeters) as valid input values in most cells. Simple forms of addition, multiplication, and division may be used as well as exponential format. Enter the DISTANCE between the "TO" and the "FROM" node along the direction specified.

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DZ Delta Z (DZ) defines the element's projected length along the global Z direction. CAESAR II accepts [compound length]—[length]—[fraction] formats (such as feet - inch - fraction or meter - decimal - centimeters) as valid input values in most cells. Simple forms of addition, multiplication, and division may be used as well as exponential format. Enter the DISTANCE between the TO and the FROM node along the direction specified.

Examples for DX, DY, DZ Fields

Element Cosines Element Length Enter the distance between the TO and the FROM node. Element Direction Cosines Direction vector or direction cosines which define the center-line of the element. For an element aligned with the "X" axis, Cos X ..... 1.0 Cos Y ..... Cos Z .....

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For an element aligned with the "Y" axis, Cos X ..... Cos Y ..... 1.0 Cos Z ..... For an element aligned with the "Z" axis, Cos X ..... Cos Y ..... Cos Z ..... 1.0

Element Offsets Element Offsets are used to correct an element's modeled dimensions back to its actual dimensions. 1

Activate by double-clicking the Offsets check box on the Pipe Element Spreadsheet. Deactivate by double-clicking a second time.

2

Specify the distances from the TO node's position in 3-D space to the actual TO end of the element.

3

Specify the distances from the FROM node’s position in 3-D space to the actual FROM end of the element.

Note:

Any offset direction distances left blank default to zero.

Thermal expansion is “0” for the offset portion of an offset element. No element flexibility is generated for the offset portion of the element. A common usage for the offset element is shown in the following figure:

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Pipe Section Data Diameter The Diameter field is used to specify the pipe diameter. Normally, the nominal diameter is entered, and CAESAR II converts it to the actual outer diameter necessary for the analysis. There are two ways to prevent this conversion: use a modified UNITS file with the Nominal Pipe Schedules turned off, or enter diameters whose values are off slightly from a nominal size (in English units the tolerance on diameter is 0.04 in.). Use to obtain additional information and the current units for this input field. Available nominal diameters are determined by the active pipe size specification, set via the configuration program. The following are the available nominal diameters. ANSI Nominal Pipe ODs, in inches (file ap.bin) ½

¾ 10 34

1 12 14 36

1½ 16 42

2 18

2½ 20

3 22

3½ 24

4 26

5 28

6 30

8 32

65 450

80 500

90 550

100 600

125 650

150

65 700

80 800

100 900

125 1000

150 1200

200 1400

JIS Nominal Pipe ODs, in millimeters (file jp.bin) 15

20 200

25 250

32 300

40 350

50 400

DIN Nominal Pipe ODs, in millimeters (file dp.bin) 15

20 25 250 300 350 1600 1800

32 400 2000

40 500 2200

50 600

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Wt/Sch The Wall Thickness/Schedule field is used to specify the thickness of the pipe. Normal input consists of a schedule indicator (such as S, XS, or 40), which will be converted to the proper wall thickness by CAESAR II. If actual thickness is entered, CAESAR II will accept it as entered. Available schedule indicators are determined by the active piping specification, set via the configuration program. The available schedules are listed below. ANSI B36.10 Steel Nominal Wall Thickness Designation: S - Standard XS - Extra Strong XXS - Double Extra Strong

ANSI B36.10 Steel Pipe Numbers: 10

20

30

40

60

80

100

120

140

160

80

100

120

140

160

ANSI B36.19 Stainless Steel Schedules: 5S

10S

40S

80S

JIS PIPE SCHEDULES 1990 Steel Schedules: 10

20

30

40

60

1990 Stainless Steel Schedules: 5S

10S

40S

DIN PIPE SCHEDULES none Note:

Only the s (standard) schedule applies to wall thickness calculations for DIN.

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CAESAR II Technical Reference Manual +Mill Tol % The Positive Mill Tolerance is is only enabled when IGE/TD/12 is active, and is used when the Base Stress/Flexibility On directive of the Special Execution Options is set to Plus Mill Tolerance. In that case, piping stiffness and section modulus is based on the nominal wall thickness, increased by this percentage. The user may change this value on an element by element basis. -Mill Tol % The Negative Mill Tolerance is read in from the configuration file for use in minimum wall thickness calculations. Also, for IGE/TD/12, this value is used when the Base Stress/Flexibility On directive of the Special Execution Options is set to Plus Mill Tolerance. In that case, piping stiffness and section modulus is based on the nominal wall thickness, decreased by this percentage. The user may change this value on an element by element basis.

Seam-Welded This directive is only activated when the IGE/TD/12 code is active. This is used to indicate when straight pipes are seam welded and affects the Stress Intensification Factor calculations for that pipe section due to Seam Welded fabrication. Corrosion Enter the corrosion allowance to be used order to calculate a reduced section modulus. A “setup file” directive is available to consider all stress cases as corroded. Insul Thk Enter the thickness of the insulation to be applied to the piping. Insulation applied to the outside of the pipe will be included in the dead weight of the system, and in the projected pipe area used for wind load computations. If a negative value is entered for the insulation thickness, the program will model refractory lined pipe. The thickness will be assumed to be the thickness of the refractory, inside the pipe.

Temperatures There are nine temperature fields, to allow up to nine different operating cases. Temperature values are checked (by the error checker) to insure they are within the code allowed ranges. Users can exceed the code ranges by entering the expansion coefficient in the temperature field in units of length/length. The expansion coefficient can be a useful method of modeling cold spring effects. Also when material 21(userdefined material) enter temperature *expansion coefficient as in the example below. Values entered in the temperature field whose absolute values are less than the Alpha Tolerance are taken to be thermal expansion coefficients, where the Alpha Tolerance is a configuration file parameter and is taken to be 0.05 by default. For example; if the user wanted to enter the thermal expansion coefficient equivalent to 11.37in./100ft., the calculation would be: 11.37in./100ft. * 1 ft./ 12in. = .009475 in./in.

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9

This would be entered into the appropriate Temperature field. Note: A cut short is no more than reducing a pipe element's length to zero (for example; if we wanted 8.5 cm of cold spring we could put in an 8.5 cm long element and then thermally shrink its length to zero). This allows the cold spring to be manipulated as an individual thermal case rather than as a concentrated force. Access to operating conditions 4 through 9 is granted through the Extended Operating Conditions input screen, accessible via the Ellipses Dots button directly to the right of the standard Temperature and Pressure input fields. This dialog box may be kept open or closed for the convenience of the user.

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CAESAR II Technical Reference Manual

Pressures There are ten pressure fields, to allow up to nine operating, and one hydrotest, pressure cases. When multiple pressures are entered, the user should be particularly careful with the set up of the analysis load cases, and should inspect CAESAR II's recommendations carefully before proceeding. Access to operating pressures 3 through 9 is granted through the Extended Operating Conditions input screen, accessible via the Ellipses Dots button directly to the right of the standard Temperature and Pressure input fields. This dialog box may be retained open or closed at the convenience of the user. Entering a value in the HydroPress field signals CAESAR II to recommend a Hydrotest load case. Enter the design gage pressure (i.e. the difference between the |internal and external pressures). Note: CAESAR II addresses negative pressures as follows: - the absolute value of the longitudinal pressure stress (PD/4t) term will be added to the appropriate code equations - pressure thrust forces applied to expansion joint ends will be compressive. - buckling is not addressed in CAESAR II. Note: The BOURDON (pressure elongation) EFFECT is "OFF" by default. (It is assumed to be nonconservative.) Users wishing to activate the BOURDON EFFECT may do so via the Special Execution Options. The BOURDON EFFECT is ALWAYS considered in the analysis of Fiberglass Reinforced Plastic pipe, Material id=20.

Piping Materials Material Name Materials are entered either by name or number. All available material names and their CAESAR II material numbers are displayed in the drop list. Since this list is quite long, entering a partial material name (such as A106) allows the user to select from matching materials. Numbers 1-17 correspond to the generic materials, without code allowable stresses. Material 18 represents the cold spring element for “cut short” and material 19 represents the cold spring element for “cut long.” Material 20 is used to define Fiberglass Reinforced Plastic (FRP) pipe. FRP Pipe requires slightly different material modeling and the spreadsheet changes to accommodate the difference. Analysis of fiberglass pipe is described in greater detail in Chapter 6 of the Technical Reference Manual. When a material has been selected from the database, the physical properties as well as the allowable stresses are obtained and placed on the spreadsheet. At any later time, if the temperature or piping code is changed, these allowable stress values are automatically updated. Material Properties Modulus of Elasticity, Poisson's Ratio, and Pipe Density fields are automatically filled in when a material number is entered. If the user wishes to override any material property extracted from the database, simply change the value to be modified after the material number has been entered.

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11

Fiberglass Reinforced Plastic (FRP)

The CAESAR II FRP pipe element models an orthotropic material whose properties can be defined by: Ea - Axial Modulus of Elasticity Eh - Hoop Modulus of Elasticity h/a

- Poisson's ratio of the strain in the axial direction resulting from a stress in the hoop direction.

G - Shear Modulus (Not related to the Elastic Modulus and Poisson’s ratio in the conventional manner.) FRP pipe is invoked from the CAESAR II element spreadsheet with a material type 20. The material name will be immediately printed and FRP properties from the configuration file will be input on the spreadsheet. Some of the material parameters are renamed when the FRP material is selected: “Elastic Modulus” changes to “Elastic Modulus/axial” and “Poisson's Ratio” changes to “Ea/Eh*n h/a”. The latter entry requires the value of the expression: (Ea*n h/a) / Eh (which happens to be equal to na/h, Poisson's ratio of the strain in the hoop direction resulting from a stress in the axial direction). The shear modulus G can be defined by entering the ratio of G/Ea (shear modulus to axial modulus) on the special execution parameters screen. Only one ratio can be entered per job. Because the hoop modulus is usually considerably higher than the axial modulus for FRP pipe, the decrease in flexural stiffness at bends and intersections due to changes in the circular cross-section is typically negligible, and so a default flexibility factor of 1 is used for these components. Similarly, since the fatigue tests performed by Markl on steel pipe will likely have no bearing on FRP design, an SIF of 2.3 is applied for all fittings. CAESAR II uses these recommendations for all FRP fittings unless specifically overridden by the user. This can be overridden on a point-by-point basis, or by forcing all calculations to adhere to the requirements of the governing code (through a CAESAR II configuration parameter). Note that if the BS 7159 or UKOOA Codes are in effect, all SIFs and flexibility factors will be calculated as per that code regardless of the configuration parameter settings.

Densities Pipe Density The appropriate pipe density is filled in automatically when a proper material number is input. This value may be overridden by the user at any time. It will then be the user’s value that gets column-duplicated through the remainder of the input.

12

CAESAR II Technical Reference Manual Insulation Density Enter the weight density of the insulation on a per unit volume basis. (If the insulation thickness specified above is negative, this field is the weight of the refractory lining, on a per unit volume basis.) If left blank then CALCIUM SILICATE is assumed for insulation having a density of: 6.655E-3. Insure that this "assumed" value is appropriate for the current application. Refractory densities are much higher than insulation densities and could lead to under sized restraints. Sample density values for both insulation and refractory materials are listed below.

MATERIAL

DENSITY (lb/cu.in.)

AMOSITE ASBESTOS

.009259

CALCIUM SILICATE

.006655

CAREYTEMP

.005787

FIBERGLASS (OWEN/CORNING)

.004051

FOAM-GLASS/CELLULAR GLASS

.004630

HIGH TEMP

.01389

KAYLO 10 (TM)

.007234

MINERAL WOOL

.004919

PERLITE / CELO-TEMP 1500

.007523

POLY URETHANE

.001273

STYRO FOAM

.001042

SUPER X

.01447

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13

Densities for some typical refractory materials are given below:

MATERIAL

DENSITY (lb./cu.in.)

A.P. GREEN GREENCAST 94

.09433

A.P. GREEN KRUZITE CASTABLE

.08681

A.P. GREEN MC-30

.08391

A.P. GREEN MC-22

.07234

A.P. GREEN KAST-SET

.06655

A.P. GREEN KAST-O-LITE 25

.05208

A.P. GREEN VSL-35AST 94

.02257

B&W

KAOCRETE B

.05787

B&W

KAOCRETE 32-C

.08333

B&W

KAO-TAB 95

.09549

B&W

KAOLITE 2200

.03241

B&W

KAOLITE 2200-HS

.04745

B&W

KAOLITE 2500-LI.

.03472

Fluid Density When the internal fluid the piping system transports would significantly effect the weight loads, the fluid density should be specified. When the specific gravity of the fluid is known, it can be entered here instead of the density, e.g. .85SG. Specific gravities are converted to the appropriate densities immediately on input. Note that to enter specific gravity, follow the numeric value with the letters SG (no spaces); this value will then be converted to density. Note:

In the default ENGLISH units system, densities are entered in pounds per cubic inch.

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CAESAR II Technical Reference Manual

Auxiliary Fields - Component Information Bends Activate by double-clicking the Bend check box on the pipe element spreadsheet. Deactivate by doubleclicking a second time.

Radius CAESAR II makes the long radius bend calculation whenever a bend is input. If the user wishes to use some other bend radius the new bend radius can be entered in this field.

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15

Type For most codes, this refers to the number of attached flanges, and can be selected from the drop list. If there are no flanges on the bend then leave the Type field blank. A bend should be considered “flanged” if there is any heavy/rigid body within 2 diameters of the bend that will significantly restrict the bends ability to ovalize. When using the BS 7159 or UKOOA Codes with Fiberglass Reinforced Plastic (FRP) pipe, this entry refers to the material laminate type, and may be 1, 2, or 3. These laminate types are All chopped strand mat (CSM) constructing with internal and external surface tissue reinforced layer. Chopped strand mat (CSM) and woven roving (WR) construction with internal and external surface tissue reinforced layer. Chopped strand mat (CSM) and multi-filament roving construction with internal and external surface tissue reinforced layer. The Laminate type affects the calculation of flexibility factors and stress intensification factors for the BS 7159 and UKOOA Codes only.

Angle The angle to a point on the bend curvature. The user may place additional nodes at any point on the bend curvature provided the added nodes are not within 5 degrees of each other. (The 5 degree node-spacing limit may be changed via the configuration file if necessary.) Note that the element TO node is always physically located at the far end of the bend. By default CAESAR II places a node at the midpoint of the bend (Designated by the letter M in this field), as well as at the 0-degree position (start) of the bend if possible.

Node Node number to be associated with the extra point on the bend. CAESAR II places unique node numbers in these fields whenever a bend is initiated. New, unique node numbers must be assigned to the points whenever the user adds points on the bend curvature. If numbering by 5’s and the TO node number for the bend element is 35, a logical choice for the node number for an added node at 30 degrees on the bend would be 34. The added nodes on the bend can be treated like any other nodes in the piping system. Nodes on the bend curvature may be restrained, displaced, or placed at the intersection of more than two pipes. Nodes on a bend curvature are most commonly used as an intersection for a dummy leg, or for the location of a restraint. All nodes defined in this manner will be plotted at the tangent intersection point for the bend.

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CAESAR II Technical Reference Manual

Miter Points Number of cuts in the bend if mitered. The bend SIF scratch pad may be invoked from the pipe spreadsheet by choosing Kaux - Review SIFs at Bend Nodes. When the user enters a valid mitered bend node number, CAESAR II tells the user if the mitered bend input is closely or widely spaced. If the bend is determined to be widely spaced and the number of miter cuts is greater than 1, then it is recommended that the bend be broken down into “n” single cut widely spaced miters, where “n” is the total number of cuts in the bend. The number of cuts and the radius of the bend are all that is required to calculate the SIFs and flexibilities for the bend as defined in the B31 codes. The bend radius and the bend miter spacing are related by the following equations: Closely Spaced Miters R=

S / (2 tan )

q=

Bend Angle / (2 n) where n = number of miter cuts

Widely Spaced Miters R=

r2 (1.0 + cot q) / 2.0

r2 =

(ri + ro) / 2.0

=

Bend Angle / 2.0

Fitting Thickness Enter the thickness of the bend if different than the thickness of the matching pipe. If the entered thickness is greater than the matching pipe wall thickness, then the inside diameter of the bend will be smaller than the inside diameter of the matching pipe. Section modulus calculations for stress computations are made based on the properties of the matching pipe as defined by the codes. The pipe thickness is used twice when calculating SIFs and flexibility factors -- once as Tn, and once when determining the mean cross-sectional radius of the pipe in the equation for the flexibility characteristic (h): h = (Tn)(R) / (r2) Tn = Thickness of bend or fitting R = Bend radius r = Mean cross-sectional radius of matching pipe = (OD - WT) / 2 OD = Outside Diameter of matching pipe WT = Wall Thickness of matching pipe

Chapter 3 Piping Screen Reference

17

Most codes use the actual thickness of the fitting (this entry) for Tn, and the wall thickness of the matching pipe for the calculation of the mean cross-sectional radius of the pipe (the WT value). More specifically, the individual codes use the two wall thicknesses as follows: For Tn:

For Mean Radius

B31.1

Fitting

Fitting

B31.3

Fitting

Matching Pipe

B31.4

Fitting

Matching Pipe

B31.5

Fitting

Matching Pipe

B31.8

Fitting

Matching Pipe

B31.8 Ch VIII

Fitting

Matching Pipe

SECT III NC

Fitting

Matching Pipe

SECT III ND

Fitting

Matching Pipe

Z662

Matching Pipe

Matching Pipe

NAVY 505

Fitting

Fitting

B31.1 (1967)

Fitting

Fitting

SWEDISH

Fitting

Matching Pipe

BS 806

N/A

N/A

STOOMWEZEN

N/A

N/A

RCC-M C/D

Matching pipe

Matching Pipe

CODETI

Fitting

Fitting

NORWEGIAN

Fitting

Fitting

FDBR

Fitting

Fitting

BS 7159

Fitting

Fitting

UKOOA

Fitting

Fitting

IGE/TD/12

Fitting

Fitting

Calculation:

The bend fitting thickness (FTG) is always used as the pipe thickness in the stiffness matrix calculations; however, note that the thickness of the matching pipe (WT) is always used in the bend stress calculations.

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CAESAR II Technical Reference Manual

K-Factor Normally the bend flexibility factor is calculated as per the requirements of the active code. The user can override this calculation by entering a value in this field.

Seam-Welded Used by the IGE/TD/12 piping code to calculate the stress intensification factors due to seam welded elbow fabrication as opposed to extruded elbow fabrication. This directive is only available when the IGE/TD/12 piping code is active.

Rigid Elements Activate by double-clicking the Rigid check box on the pipe element spreadsheet. Deactivate by doubleclicking a second time. Enter the rigid element weight. This value should always be zero or positive and should not include the weight of any insulation or fluid.

CAESAR II automatically includes 1.0 times the fluid weight of equivalent straight pipe. CAESAR II automatically includes 1.75 times the insulation weight of equivalent straight pipe. Rigid elements with zero weight are considered to be modelling constructs and do not have fluid or insulation weight added. The rigid element stiffness is proportional to the matching pipe, i.e. a 13 in. long 12 in. diameter rigid element is stiffer than a 13 in. long 2 in. diameter rigid element. This fact should be observed when modelling rigid elements that are part of a small pipe/large vessel, or small pipe/heavy equipment model. The stiffness properties are computed using 10 times the entered thickness of the rigid element. For additional details see Chapter 6 of this manual. The length must be entered in the Delta Length field (DX, DY, DZ). See the discussion of the valve and flange database (see "Valve/Flange Database" on page 81) for the automatic input of these types of components.

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19

Expansion Joints Activate by double-clicking the Expansion Joint check box on the pipe element spreadsheet. Deactivate by double-clicking a second time.

Zero Length Expansion Joints Used to model hinged and gimballed joints. Leave the DX, DY, and DZ fields blank or zero. Define completely flexible stiffnesses as 1.0, and completely rigid stiffness as 1.0E12. All stiffnesses must be entered.

Finite Length Expansion Joints The DX, DY, and DZ fields should describe the change in dimensions required to get from one end of the flexible bellows connection to the other. The transverse and bending stiffnesses are directly related for finite length joints. The user should input only one of these stiffnesses. CAESAR II will calculate the other stiffness automatically based on flexible length, effective ID, and the other stiffness. It is recommended that the user enter the transverse stiffness and leave the bending stiffness blank.

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CAESAR II Technical Reference Manual

Bellows Stiffness Properties If the element length is zero then all stiffnesses should be defined by the user. If the element length is not zero then either the bending or the transverse stiffness should be left blank. CAESAR II will automatically calculate the stiffness not entered. (For rubber expansion joints, all stiffnesses may be entered.) If the torsional stiffness value is not specified, CAESAR II will use a default value of . Bending "STIFFNESSES" from EJMA (and from most expansion joint manufacturers) that are to be used in a finite length expansion joint model should be multiplied by (4) before being used in any piping program. Bending "STIFFNESSES" from EJMA (and from most expansion joint manufacturers) that are to be used in a ZERO length expansion joint model should be used without modification. Use (1.0) for bellows stiffnesses that are completely flexible. Use (1.0E12) for rigid bellows stiffnesses. Zero Length expansion joints can be used in many modelling applications to define struts, hinged ends, etc. The orientation of zero length expansion joints is taken from the element that precedes the expansion joint providing the "TO" node of the proceeding element is equal to the "FROM" node on the expansion joint element. If the preceeding element does not go "INTO" the expansion joint, then the orientation will be taken from the element that follows the expansion joint providing it properly "LEAVES" the joint.

Effective ID The effective inside diameter for pressure thrust (from the manufacturer’s catalog). For all load cases including pressure CAESAR II will calculate the pressure “thrust force” tending to blow the bellows apart (provided the pressure is positive). If left blank, or zero, then no axial thrust force due to pressure will be calculated. Many manufacturers give the effective area of the expansion joint: Aeff. The Effective ID is calculated from the effective area by: Effective ID = (4Aeff / )1/2

Reducers

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21

Activate or deactivate this option by double-clicking the Reducer check box on the piping element spreadsheet. Optionally, enter the TO END Diameter 2, Thickness 2, and Alpha values of the reducer. The FROM END diameter and wall thickness of the reducer element will be taken from the current piping element spreadsheet. CAESAR II will construct a concentric reducer element made of ten pipe cylinders, each of a successively larger (or smaller) diameter and wall thickness over the element length. CAESAR II will calculate SIFs according to the current piping code (see Code Compliance Considerations in the CAESAR II Technical Reference Manual for more information) and apply these internally to the Code Stress Calculations. These SIFs are dependent on the slope of the reducer transition (among other code-specific considerations), labeled Alpha in the figure above. If Alpha is left blank the program will calculate this value based on the change in pipe diameter over 60% of the entered element length. If entered, Diameter 2 and Thickness 2 will be carried forward when the next pipe element is created as Diameter and Wt/Sch. If not specified, Diameter 2 and Thickness 2 will be assumed equal to those values entered as Diameter and Wt/Sch on the following element spreadsheet.

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CAESAR II Technical Reference Manual

The Piping Error Checker will report the value of alpha used by CAESAR II (see above picture) if no value for alpha is entered on the input spreadsheet.

Diameter 2 Optionally enter the diameter of the TO END of the reducer element. (The FROM END diameter is obtained from the Diameter field of the piping spreadsheet.) The value entered will carry forward as the diameter of the following element. Nominal values are converted to actual values if that feature is active. If left blank, the program will calculate "Alpha" using the diameter from the following element as Diameter 2.

Thickness 2 Enter the wall thickness of the "TO END of the reducer element. (The FROM END thickness is obtained from the Wall Thickness/Schedule field of the piping spreadsheet.) The entered value will carry forward as the wall thickness of the following element. Nominal values are converted to actual values if that feature is active.

Alpha Alpha is the slope of the reducer transition in degrees. If left blank, the value will be set from an estimated slope equal to the arc tangent X [ 1/2(the change in diameters) (60% of the entered reducer length)].

R1 Enter the transition radius for the large end of the reducer, as shown in Appendix 4, Table 8 of IGE/TD/12 Code (enabled only when IGE/TD/12 is active).

R2 Enter the transition radius for the large end of the reducer, as shown in Appendix 4, Table 8 of IGE/TD/12 (enabled only when IGE/TD/12 is active)..

SIFs & Tees Activate by double-clicking the SIFs and Tees check box on the Pipe Element Spreadsheet. Deactivate by double-clicking a second time.

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23

There are two basic component types: Three element “intersection” components, and Two element “joint” components. A fully defined intersection model requires that three pipes frame into the intersection node, and that two of them are co-linear. Partial intersection assumptions are made for junctions where the user has coded one or two pipes into the intersection node, but these models are not recommended. Two element “joint” components can be formed equally well with one or two elements framing into the node. As usual, the intersection or joint type and properties need only be entered on one of the elements going to the junction. CAESAR II duplicates the intersection characteristics for all other pipes framing into the intersection. Users are urged to fully review the WARNING messages coming from CAESAR II during error checking. These messages detail to the user any assumptions made during the assembly and calculation of the intersection SIFs. The available intersections and joint types are shown in the table that follows, along with the other parameters that can affect the stress intensification factors for the respective component.

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CAESAR II Technical Reference Manual

Input Items Optionally Effecting SIF Calculations 1

Reinforced Fabricated Tee

2

Pad Thk

Ftg Ro

CROTCH

Unreinforced Fabricated Tee

Ftg Ro

CROTCH

3

Welding Tee

Ftg Ro

CROTCH

4

Sweepolet

CROTCH

5

Weldolet

CROTCH

6

Extruded Welding Tee

7

Girth Butt Weld

Weld d or ID

8

Socket Weld (No Undercut)

FILLET

9

Socket Weld (As Welded)

FILLET

10

Tapered Transition

Weld d

11

Threaded Joint

12

Double Welded Slip-On

13

Lap Joint Flange (B16.9)

14

Bonney Forge Sweepolet

15

Bonney Forge Latrolet

16

Bonney Forge Insert Weldolet

17

Full Encirclement Tee

Ftg Ro

CROTCH

WELD ID

Ftg Ro

WELD ID

The input data cells are defined as follows: Pad Thk. Thickness of the reinforcing pad for reinforced fabricated or full encirclement tees, intersection type #1 and #17 respectively. The pad thickness is only valid for these intersection types. Note that in most piping codes the beneficial effect of the pad’s thickness is limited to 1.5 times the nominal thickness of the header. This factor does not apply in BS 806 or Z184, and is 2.5 in the Swedish piping code. If the thickness of a type 1or type 17 intersection is left blank or zero the SIFs for an unreinforced fabricated tee are used. Ftg Ro. Fitting outside radius for branch connections. Used for reduced branch connections in the ASME and B31.1 piping codes, Bonney Forge Insert Weldolets, and for WRC 330/329 intersection SIF calculations. Setup file directives exist to invoke the WRC 330/329 calculations, and to limit the application of the reduced branch connection rules to unreinforced fabricated tees, sweepolets, weldolets, and extruded welding tees. If omitted, FTG ro defaults to the outside radius of the branch pipe. Crotch R. The crotch radius of the formed lip on an extruded welding tee, intersection type 6. This is also the intersection weld crotch radius for WRC330 calculations. Specifying this value when it is known can result in a 50% reduction in the stress intensification at the WRC 330 intersection. Basically, if the user makes an attempt to reduce the stress riser at a fabricated intersection, by guaranteeing that there will be a smooth transition radius from the header to the branch pipe, then he may reduce the resulting stress intensification by a factor of 2.0.

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25

Weld(d). Defines the “average” circumferential weld mismatch measured at the inside diameter of the pipe. Used for Butt Welds and Tapered transitions. Note that this is the average, and not the maximum mismatch. Users must themselves make sure that any maximum mismatch requirements are satisfied for their particular code. Fillet. The fillet leg length, and is used only in conjunction with a socket weld component. For an unequal leg fillet weld, this value is the length of the shorter leg. Note that if a fillet leg is given, both socket weld types result in the same SIF. See appendix D of the B31 piping codes for further clarification. Weld ID. The following are valid entries: 0 and 1. 0 indicates an as welded fitting, 1 indicates a finished or ground flush fitting. This entry is used for Bonney Forge sweepolets and insert weldolets, as well as butt welds in the Swedish piping code. B1. This entry defines the primary stress index to be used for the given node on the current element. This entry is only applicable for ASME Class 2 and 3 piping. For the BS 7159 Code, the B1 field is used to enter the pressure stress multiplier (m), if other than as per the code requirements. For straight pipe, m = 1.0; for bends and tees, m is defined in Figures 7.1 and 7.12 of the BS 7159 Code. B2. This entry defines the primary stress index to be used for the given node on the current element. This entry is only applicable for ASME Class 2 and 3 piping. If omitted, B1 and B2 are defaulted as shown as follows: Straight Pipe:

B1=0.5 B2=1.0

Curved Pipe:

B1=-0.1+0.4h; but not <0 or >0.5 B2=1.30/h2/3; but not <1.0; h=tR/rm2

Intersections:

B1=0.5

Butt-Welded Tees: B2b=0.4(R/T)2/3 but not <1.0 B2r=0.5(R/T)2/3 but not <1.0 Branch Connections: (r<0.5R) B2b=0.50 C2b but not <1.0 B2r=0.75 C2r but not <1.0 C2b=3(R/T)2/3 (r/R)1/2 (t/T)(r/FTG ro) but not <1.5 C2r=1.15(r/t)1/4 but not <1.5 The SIF(IN) and SIF(OUT) fields may be used to override the CAESAR II calculated values for any intersection. Override values only apply for the single element they are defined on. SIFs may be calculated for partial intersections and dummy legs.

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CAESAR II Technical Reference Manual

Note: When IGE/TD/12 is active, the SIF/TEE spreadsheet changes its appearance to accommodate specialized specialized SIF parameters. Refer to supplementary IGE/TD/12 documentation for further information.

SIF / Tee Node Number Enter the node number where a Stress Intensification exists. This may be any node in the system, but is most often at a pipe intersection or joint. If the node is at an Intersection, stress intensification factors will be automatically calculated for all pipes going to the intersection providing the intersection "TYPE" is specified. The intersection type needs to only be entered once. CAESAR II will find all other pipes framing into the intersection and apply the appropriate SIFs accordingly. If the node is at a two-pipe Joint, i.e. a butt weld, stress intensification factors will be calculated for the two pipes going to the joint node providing the joint "TYPE" is specified. The joint type needs to only be entered once. CAESAR II will find the other pipe completing the joint. If the node is not at an intersection or a joint then the Type field should be left BLANK and the "USER DEFINED" SIFs entered in the SIF(i) and SIF(o) fields. User entries in the SIF(i) and SIF(o) fields only apply to the element on which they are defined. User defined stress intensification factors, must be greater then or equal to one. The user can get CAESAR II to calculate and display code defined SIFs while in the SIF scratchpad. This scratchpad is accessed via the K-Aux option on the pipe spreadsheet. Parameters used in the scratchpad may be modified so that the effects of different geometries and thicknesses can be observed. Most changes made in the scratchpad may be automatically transferred back into the input, if desired. If the node is on any part of a bend's curvature then the following applies: 1

User defined SIFs won't override code calculated SIFs for bends, although a SETUP file directive exists to override this default, i.e. ALLOW_USERS_BEND_SIF=YES. If this parameter appears in the setup file then users may specify SIFs for bend "to" nodes. The SIFs so specified will apply for the entire bend curvature.

2

User defined SIFs will apply to straight pipe going to points on a bend curvature regardless of any parameter in the setup file. This option is commonly used to intensify injector tie-ins at bends, or dummy legs, or other bend attachment-type of supports.

User-Defined SIFS Anywhere in the Piping System Unless the piping element is a bend, SIFs for non-intersection points are normally taken to be 1.0. If for some reason the SIF should be greater than (1.0) the user may enter the non-unity SIF in the Intersection Auxiliary field without specifying the intersection type. Note that a user defined SIF only acts at the node on the current element.

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27

Stress Intensification Factors (Details) Stress intensification factors are calculated automatically for bends and defined intersections as specified by the applicable piping code. The user may enter specific stress intensification factor for any point in the piping system by activating the SIFs and Tees check box on the pipe spreadsheet. The node number where the stress is to be intensified is entered in the first available Node field, and the in-plane and out-plane stress intensification factors are entered in the SIF(i) and the SIF(o) fields, respectively. The only exception is that users cannot specify SIFs for bend elements (unless the User Bend SIF directive is activated in the configuration file). Code defined SIFs always apply. CAESAR II will not allow user-defined stress intensification factors to be less than 1.0. The node to be intensified must be the To or the From node on the current element. Stresses are only intensified at the element end going to the specified node. For example, if two pipes frame into node 10, one going from 5 to 10, and the other from 10 to 15; and a stress intensification factor of 2.0 for node 10 is defined on the element from 5 to 10, then the 10 end of the element from 5 to 10 will have a stress intensification of 2.0, and the 10 end of the element from 10 to 15 will have a stress intensification of 1.0. User defined stress intensification factors can be used to override code calculated values for nodes at intersections. For example, let node 40 be an intersection defined by an unreinforced fabricated tee. The header pipes framing into the intersection go from 35 to 40 and from 40 to 45. The branch pipe framing into the intersection goes from 175 to 40. The code-calculated values for the stress intensification factors in the header pipes are: SIF(i)

= 4.50

SIF(o)

= 3.75

and in the branch pipe are SIF(i)

= 6.70

SIF(o)

= 5.58

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CAESAR II Technical Reference Manual

Also assume that finite element analysis of the intersection showed the header stress intensification factors to be 2.3 and 1.87, respectively, and the branch stress intensification factors to be equal to the code recommended values, i.e. 6.70 and 5.58. To properly override the code-calculated stress intensification factors for the header pipes, two pipe elements will have to be modified: 35 to 40 Node

40 Type: SIF(i): 2.3 SIF(o): 1.87

40 to 15 Node

40 Type: SIF(i): 2.3 SIF(o): 1.87

The stress intensification for the branch pipes can be calculated according to the code, so, part of the branch pipe spreadsheet might appear: 175 to 40

NODE

40

Type:

2 - Unreinforced

SIF(i): SIF(o): If either of the SIF fields for the header elements going to 40 were left blank, the code-calculated value would be used in its place. This is only true where code-calculated values exist along with user-specified values. If the element from 110 to 115 needs the stress intensification factors for each of its ends is 2.0, then a part of that element's spreadsheet might appear: 110 to 115

Node

110

Type: SIF(i):

2.0

SIF(o):

Node: Type:

115

Chapter 3 Piping Screen Reference

SIF(i):

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2.0

SIF(o): Leaving the out-of-plane stress intensification factor blank implies that it is equal to the in-plane stress intensification factor. There are no code-calculated values to override these user-input values. The user is not permitted to override code-calculated stress intensification factors for bend elements (unless the Allow User's Bend SIF directive is activated in the configuration file). Additionally, bend stress intensification factors will supersede any code-calculated intersection stress intensification factors for the same node. This characteristic allows the user to apply code-calculated intersection stress intensification factors to dummy legs without disturbing the normal bend stress intensification factors. The node on the dummy leg, that is also on the bend curvature, is defined as an intersection on the Intersection SIF Scratchpad. The intersection stress intensification factors will be calculated and can be applied to the dummy leg end that connects to the bend. Bend stress intensification factors are unchanged. Stress intensification factors can be calculated for intersections having one, two, or three pipes framing into it. Where two pipes form a partial intersection, CAESAR II assumes that the larger pipe is the header and the smaller the branch. Where one pipe forms a partial intersection, CAESAR II assumes that the intersection is full sized. CAESAR II will not calculate stress intensification factors for intersections having more than three pipes framing into it. The stress intensification factors calculated by CAESAR II can be viewed interactively from the pipe spreadsheet by selecting either the KAUX - REVIEW SIFS AT INTERSECTION NODES menu item or the KAUX REVIEW SIFS AT BEND NODES menu item. One of the following SIF scratchpads will appear after typing in the node number to review when prompted. Note that the Node must be a valid Bend node when Reviewing SIFs at Bends.

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At this point the user may interactively change any of the spreadsheet data and recalculate the SIFs. This allows the user to see the effect that changing geometries and properties have on code stress intensification factors. Note: CAESAR II gives the user the opportunity to transfer back to the actual model any data which might be changed in the scratch pad.

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Auxiliary Fields - Boundary Conditions Restraints Activate the restraint auxiliary by double-clicking on the check box. Deactivate by double-clicking a second time.

If more than four restraints are to be specified on one element, the additional restraints may be placed on any other input spreadsheet. Note Do not use restraints in these three situations: 1) Imposed Displacements Specify displacements for the point using the Displacement Auxiliary field. 2) Flexible Nozzles Use the Nozzles check box to open the Nozzles Auxiliary Data field to input the vessel or tank characteristics required by WRC 297, PD 5500, or API 650 to calculate local nozzle flexibilities. Once these flexibilities have been calculated, CAESAR II automatically inserts the necessary restraints and flexibilities into the piping model. 3) Hangers program designed or pre-defined spring hangers

Use the Hangers check box to open the Hanger Auxiliary Data field.

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Node Node number where the restraint is to act. Note:

The node number does not have to be on the current element.

CNode Optional connecting node. Restraints with connecting nodes can be used to tie one node in the piping system to any other node in the system. If left blank then the restraint node is tied, via the restraint stiffness, to a fixed point in space. If the connecting node is specified then the restraint node is tied, via the restraint stiffness, to the connecting node. In all cases, CNodes associate nodal degrees of freedom. Additionally, CNodes can be used to geometrically connect different parts of a model graphically. This option is controlled via the setup file directive Connect Geometry through CNodes (on page 18). See Chapter 2 of the this manual for additional information on this topic.

Type The following restraints can be activated by selecting them from the drop list in the Restraint Auxiliary field. The use of these restraints is detailed in Chapter 3 of the CAESAR II Applications Guide. Restraint Type

Abbreviation

1

Anchor

ANC

2

Translational Double Acting

X, Y, or Z

3

Rotational Double Acting

RX, RY, or RZ

4

Guide, Double Acting

GUIDE

5

Double Acting Limit Stop

LIM

6

Translational Double Acting Snubber

XSNB, YSNB, ZSNB

7

Translational Directional

+X, -X, +Y, -Y, +Z, -Z

8

Rotational Directional

+RX, -RX, +RY, etc.

9

Directional Limit Stop

+LIM,-LIM

10 Large Rotation Rod

XROD, YROD, ZROD

11 Translational Double Acting Bilinear

X2, Y2, Z2

12 Rotational Double Acting Bilinear

RX2, RY2, RZ2

13 Translational Directional Bilinear

-X2, +X2, -Y2, etc.

14 Rotational Directional Bilinear

+RX2,-RX2, +RY2, etc.

15 Bottom Out Spring

XSPR, YSPR, ZSPR

16 Directional Snubber

+XSNB,-XSNB,+YSNB, etc.

Anchor Restraint is defined for “ALL” degrees of freedom at the node.

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X , Y, or Z Translational restraints may be preceded by a (+) or (-). If a sign is entered, it defines the direction of allowed free displacement along the specified degree of freedom. (i.e. a +Y restraint is restraint against movement in the minus -Y direction and is free to move in the plus Y direction).

RX, RY, or RZ Rotational restraints may be preceded by a (+) or (-). If a sign is entered, it defines the direction of allowed free displacement along the specified degree of freedom.

Guide Transverse restraint that may be skewed.

LIM Limit stops are axial restraints that may be preceded by a (+) or (-). If a sign is entered, it defines the direction of allowed free displacement along the element longitudinal axis.

XSNB, YSNB, ZSNB Snubbers are restraints that engage only during quick movements such as those induced by a shock. They only act on the piping system in the Occasional load case. Snubbers may be preceded by a (+) or a (-).

X2, Y2, Z2 Bilinear supports are restraints that have two different stiffnesses associated with them. The stiffness is dependent upon the loading on the support. Bilinear supports may be preceded by a (+) or a (-). K2 Post yield stiffness of a bilinear restraint. When the load on the restraint exceeds Fy then the stiffness on the restraint changes from K1 to K2. The value of K2 may be negative, modelling shallow trench or groove-type pipeline supports. K2 VALUES OF ZERO WILL BE TREATED AS RIGID. For very small stiffnesses enter a value of 1.0.

XSPR, YSPR, ZSPR Spring supports that may be preceded by a (+) or a (-). "Bottom out" spring. Additional required input is the spring rate, allowed travel, and initial load. If the allowed travel in the direction of support is exceeded, the spring "bottoms-out".

X (cosx, cosy, cosz) or X (vecx, vecy, vecz) Translational skewed restraints. May be preceded by a (+) or (-). If a direction vector is entered, i.e. vecx, vecy, vecz, CAESAR II will convert the direction vector into the corresponding cosines.

RX (cosx, cosy, cosz) or RX (vecx, vecy, vecz) Rotational skewed restraints.

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XROD, YROD, ZROD Translational, large rotation, rod or hanger-type restraints. May be preceeded by a (+) or (-) sign to indicate the orientation of the pivot point about which the rod swings. A (+) is assumed, and in the case of a YROD this implies that the pivot point is above the pipe. Additional REQUIRED input is the rod or hanger length.

XROD (COSX, COSY, COSZ) or XROD (VECX, VECY, VECZ) Translational skewed, large rotation rod or hanger type restraint.

Stif Stiffness associated with any support, guide, limit stop, rod |or spring that can be defined as a restraint. If left blank then |the defined restraint will be considered rigid. The default |rigid restraint stiffness is 1.0E12. K1 is the initial stiffness of a bilinear restraint (i.e. X2). Any positive stiffness may be entered if the restraint is not rigid. Stiffnesses greatly in excess of 1.0E15 should be avoided. If a stiffness value is specified for an anchor, the entered stiffness will apply for all (6) degrees of freedom at the anchored node.

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Gap This is a multiple use field defined as follows: TYPE = X Y Z GUI LIM RX RY RZ GAP (UNITS: ^01) - Distance along the restraint line of action the restrained node may travel before resistance to movement begins. The gap value must be positive. For rotational restraints the gap is given in degrees. If the translational restraint is not preceded by a sign, then the restraint is double acting and the gap will be taken to exist for both positive and the negative displacements along the line of action (i.e. if a 0.25 in. gap is specified at a +Y restraint, then the restrained node may move freely 0.25 in. in the minus Y direction before restraint occurs. The gap specification does not affect the amount of free displacement that can occur along the positive Y direction in this example). When defining windows of allowed movement it is not uncommon to place two restraints having the same line of action, but with different signs at the same node. This configuration is perfectly legal. The user is cautioned to remember to form the window with signs on restraints rather than with signs on gaps. In CAESAR II a gap is a measure of length and is always positive.

Examples: TYPE GUI

GAP 1/4 ... One quarter ^01 gap on either side of the "guided" restraint.

TYPE +Y GAP 3.0 ... Three ^01 gap BELOW the support that must be closed before the +Y support begins acting. TYPE RX GAP 5.0 ... Five degree gap about the X axis about which the pipe may rotate freely before rotational restraint occurs.

TYPE = XROD YROD ZROD Len (UNITS: ^01) - Swinging length of the rod or hanger. Distance along the restraint line of action from the restrained node to the pivot point. The restraint swings about the pivot point. If a CNODE is defined then the restraint swings about the CNODE. "Len" is a required entry. TYPE = X2 Y2 Z2 RX2 RY2 RZ2 K2 (UNITS: ^14 ^15) - Post yield stiffness of a bilinear restraint. When the load on the restraint exceeds Fy then the stiffness on the restraint changes from K1 to K2. The value of K2 may be negative, modelling shallow trench or groove-type pipeline supports. K2 VALUES OF ZERO WILL BE TREATED AS RIGID. For very small stiffnesses enter a value of 1.0. TYPE = XSPR YSPR ZSPR "x" (UNITS: ^01) Travel along the spring axis before "bottom-out" occurs. In the case of a typical YSPR, this is the movement in the negative "Y" direction before the spring bottoms out. TYPE = XSNB YSNB ZSNB

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dmp - Future use intended for snubber damping value.

Mu This is a multiple use field defined as follows: TYPE = X Y Z GUI LIM MU (UNITS: Unitless) - Static friction coefficient. Friction provides resistance to movement along the direction normal to the restraint line of action. The magnitude of the friction force is equal to MU * Fn, where Fn is the normal force on the restraint. A friction coefficient may be automatically assigned to every new translational restraint by assigning a value to the Coefficient of Friction field (see "Coefficient of Friction (Mu)" on page 5) in the Configure/Setup module. TYPE = XROD YROD ZROD Fi (UNITS: ^02 ) - Initial spring load. This field should be left blank for a rigid YROD. If the YROD is modelling a spring hanger, then the hanger stiffness should be entered into the STIF field, and the initial cold load on the hanger should be entered here. TYPE = X2 Y2 Z2 RX2 RY2 RZ2 Fy (UNITS: ^02 ^04 ) - Yield Load. If the load on the support is less than "Fy" then the initial stiffness K1 is used. If the load on the support is greater than "Fy" then the second stiffness "K2" is used. TYPE = XSPR YSPR ZSPR F (UNITS: ^02 ) - Initial spring cold load. This input is required, and is almost always positive. TYPE = XSNB YSNB ZSNB na - Not Applicable. This field is not used when the restraint TYPE is snubber.

Hangers Activate the hangers auxiliary by double-clicking on the check box. Deactivate by double-clicking a second time.

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Node The node to which the hanger is connected.

CNode The CNode, or connecting node number, is used only when the other end of the hanger is to be connected to another point in the system, such as another pipe node.

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Hanger Table The following spring tables are currently included in CAESAR II: 1. Grinnell

2. Bergen Power

3. Power Piping

4. NPS Industries

5. Lisega

6. Fronek

7. Piping Technology

8. Capitol

9. Piping Services

10. Basic Engineers

11. Inoflex

12. E. Myatt

13. SINOPEC

14. BHEL

15. Flexider

16. Carpenter & Paterson

17. Comet

18. Hydra

19. Sarathi

20. Myricks

21. China Power

22. Pipe Supports USA

23. Quality Pipe Supports

Additional design options are invoked by further modifying the hanger table number: Add + 100 to get Extended Range Add + 200 to get Cold Load Design Add + 400 to get the Hot load centered if possible. For example, to use Grinnell Springs and cold load design the user would enter: 1 + 200 = 201. To use Grinnell “Extended Range” springs, Cold Load Design, and to get the Design Hot load centered in the middle of the hanger table, if possible, the user would enter: 1 + 100 + 200 + 400 = 701.

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A single job can use any combination of tables. The hanger table can be specified on the individual hanger spreadsheet, or can be specified on the Hanger Run Control Spreadsheet (see "Hanger Data" on page 103). If a spring table is entered in the Hanger Design Control Spreadsheet then it is used as the default for all subsequent hangers defined. The Hanger Design Control Spreadsheet defaults to the hanger tablespecified in the configuration file. The maximum load range was included in CAESAR II to permit the selection of less expensive variable support hangers in place of constant effort supports when the spring loads are just outside the manufacturers recommended range. Users should make sure that the maximum load range is available from the manufacturer as a standard item. Cold Load Spring Hanger Design. Cold Load Spring Hanger Design is a method of designing the springs, whereby the hot (or operating) load is supported in the cold (or installed) position of the piping. This method of spring design offers several advantages over the more usual hot load design: Hanger stops are easier to remove. There is no excessive movement from the neutral position when the system is cold or when the stops are removed. Spring loads can be adjusted before the system is brought up to temperature. Some feel that the cold load approach yields a much more dependable design. In some system configurations, operating loads on connected equipment are lower. A typical configuration resulting in this “load-reduction” is one where a hot vertical riser, anchored at the bottom, turns horizontally into a nozzle connection. The spring to be designed is at the elbow adjacent to the nozzle. Operating loads are lower because the difference between the hot and cold loads counters the moment produced by the vertical thermal expansion from the anchor. The disadvantages to cold load design are In some systems, in the hot condition the loads on rotating equipment may be increased by a value proportional to the spring rate times the travel. Most installations are done on a hot load design basis. The decision to use hot or cold load hanger design rests with the user. Middle of the Table Hanger Design. Many designers prefer that the hot load be centered as close as possible to the middle of the spring table. This is to provide as much “variability” either way before the spring bottoms out when the system is hot. This was a much more needed feature, before effective computer modelling of piping systems, when the weights at hangers were approximated by chart methods or calculated by hand. Activating this option does not guarantee that spring hot loads will be at the middle of the spring table, but CAESAR II makes every effort to move the hot load to this position. The CAESAR II design algorithm will go to a higher size spring if the design load is closer to the middle of the larger springs range, but will never switch spring types. This option can only result in a one size larger spring when it is effective. CAESAR II will attempt to move the hot load to the next higher spring when it is within 10% of the maximum travel range for the spring. If the new spring is not satisfactory then the old one will be used, even though its hot load is within 10% of the high end of the table load range, to get a springs hot load close to the middle of the table.

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Extended Load Range Springs. Extended load ranges are the most extreme ranges on the spring load table. Some manufacturers build double spring supports to accommodate this range, and others adjust the top or bottom travel limits to accommodate either end of the extended table. Before using the maximum ranges, the user should make sure that the manufacturer can properly supply the spring. Use of the extended range often eliminates the need to go to a constant effort support. Lisega springs do not support the "extended range" idea. A request for extended Lisega springs results in the standard Lisega spring table and ranges.

Hanger/Can Available Space This tells CAESAR II how much room, above or below the pipe, there is to install the hanger or can. If the value entered by the user is negative, then CAESAR II will assume that a can is to be installed. If the value entered is positive then CAESAR II will assume that a hanger is to be in installed. Hangers or cans will be selected for a particular location only if they can be installed in the space allotted. The precise definition of available space varies with the manufacturer. Drawings and tables for each manufacturer are shown at the end of this section. This is the available vertical clearance for the hanger or can:

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If the Available Space is not an important design criteria, then the field should be left blank or zero. If the Available Space is positive, then the vertical clearance will be assumed to be above the pipe and a hanger will be designed. If the Available Space is negative, then the vertical clearance will be assumed to be below the pipe and a can will be designed. When the Available Space is the governing factor in a hanger design, several smaller springs are typically chosen in place of one large spring.

Allowable Load Variation (%) This is the user specified limit on the allowed variation between the hot and cold hanger loads. If not specified, the only limit on load variation is that inherent in the spring table. This is approximately 100% when the hot load is smaller than the cold load, and 50% when the hot load is larger than the cold load. Hot loads are smaller than cold loads whenever the operating displacement in the Y direction is positive. The default value for the load variation is 25%. The user is advised to enter this value in the Hanger Run Control Spreadsheet before any hangers are defined. Bergen-Paterson is the only manufacturer that specifically gives 25% as a design limit. The Allowable Load Variation is the percentage variation from the hot load:

Variation =

(Cold Load) - (Hot Load) Hot Load

or as may be more familiar: Variation =

(Travel)(Spring Rate) Hot Load

The Allowable Variation is entered as a percentage, i.e. twenty five percent would be entered 25.0. The Allowable Load Variation can have different values for different hanger locations if necessary by entering the chosen value on the individual hanger spreadsheets or it can be entered on the Hanger Design Control Spreadsheet to apply to all hangers in the model.

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Rigid Support Displacement Criteria This is a parameter used to determine if there is sufficient travel to design a spring. The Rigid Support Displacement Criteria is a cost saving feature that replaces springs that are not needed with rigid rods. The hanger design algorithm operates by first running a restrained weight case. From this case the load to be supported by the hanger in the operating condition is determined. Once the hanger design load is known, an operating case is run with the hot hanger load installed to determine the travel at the hanger location. If this determined hanger travel is less than the Rigid Support Displacement Criteria then a rigid Y support is selected for the location instead of a spring. If the Rigid Support Displacement is left blank or zero, the criteria will not be applied. The Rigid Support Displacement Criteria may be specified on the Hanger Run Control Spreadsheet, or on each individual hanger spreadsheet. The value specified on the Run Control Spreadsheet is used as the default for all hangers not having it defined explicitly. A typical value to be used is 0.1 in. Important: In some cases a Single directional restraint should be inserted instead of a rigid rod. Rigid rods are double acting restraints which can in some cases develop large “hold down” forces that don’t really exist because the support has lifted off, or because the rigid rod has bowed slightly. When this condition develops the user should rerun the hanger design inserting single directional restraints where rigid rods were put in by CAESAR II. Hangers should probably never be replaced by rigid rods in very stiff parts of the piping system that are usually associated with rotating equipment or vessel nozzles that need to be protected.

Maximum Allowed Travel Limit To specify a limit on the amount of travel a variable support hanger may undergo, specify the limit in this field. The specification of a maximum travel limit will cause CAESAR II to select a constant effort support if the design operating travel exceeds this limit, even though a variable support from the manufacturer table would have been satisfactory in every other respect. Constant effort hangers can be designed by inputting a very small number for the Maximum Allowed Travel Limit. A value of 0.001 is typical to force CAESAR II to select a for a particular location.

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No. Hangers at Location If left blank, CAESAR II will attempt to find a single hanger that suits all design requirements at the location. If a single hanger cannot be found, then CAESAR II will try to find a double hanger that satisfies all design requirements. If a double hanger cannot be found, then CAESAR II will recommend a constant effort support hanger for the location. If the user wants to use a different upper limit on the number of springs that CAESAR II will consider for a location, then the negative of that number should be entered in this field. For example, if the user wants to use as few springs as possible, yet is willing to use as many as 5 springs if necessary, -5 should be entered in the No. of Hangers field. To directly specify the number of springs to be designed at a location, enter that number in the No. of Hangers field. Note:

Enter only positive numbers in the No of Hangers field.

Allow Short Range Springs CAESAR II gives the user the option of excluding short range springs from consideration from the selection algorithms. In some instances short range springs are considered specialty items and are not used unless their shorter length is required for clearance reasons. In this case, this check box should be cleared by the user. If this option is not activated, CAESAR II will select a mid-range spring over a short-range spring, assuming they are more standard, readily available, and in general cheaper than their short-range counterparts. If the default should be that short range springs are used wherever possible, then check the box on the Hanger Design Control Spreadsheet.

Operating Load To override the operating load that CAESAR II is calculating, enter the desired value in the Operating Load field. This value is normally entered when the user thinks that loads on a piece of equipment will be reduced if a hanger in the vicinity of the equipment is artificially caused to carry a proportionately larger part of the total load. This operating load is the hot load the hanger is designed to support after it undergoes any travel due to the thermal expansion of the piping. CAESAR II’s calculated hanger operating loads may be read from the hanger table printed in the output processor. The column title is “HOT LOAD.” The user’s entered value will similarly show up in this table if defined. The total desired operating load at the location should be entered. If there are two hangers specified at the location and each should carry 500 lb., then the operating load specified should be 1,000 lb.

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Multiple Load Case Design The spring selection algorithm can be based on one or more operating conditions. A two-pump installation, where only one pump operates at a time, is a good application for multiple load case hanger design. There are currently thirteen different multiple load case design algorithms available: Design spring per operating case #1. Design spring per operating case #2. Design spring per operating case #3, #4, #5, #6, #7, #8, and #9. Design spring for maximum operating load. Design spring for maximum travel. Design spring for average load and average travel. Design spring for maximum load and maximum travel. The Multiple Load Case Design option can be specified at the global level in the Hanger Design Control Data Spreadsheet (see "Hanger Data" on page 103). The globally specified option will apply for all hanger design locations unless overridden in a specific hanger design spreadsheet. Enter the number of operating thermal cases to be considered when sizing springs for this system in the Hanger Design Control Spreadsheet. This value defaults to 1.0. Also enter the Multiple Load Case Design option to be the default value (unless the design option is to be specified individually for each hanger to be designed in the system).

Example Problem of a Multiple Load - Case Spring - Hanger Design This example illustrates the different hanger designs that can result from the use of different multiple load case design options.

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Free Anchor/Restraint at Node Anchors, or restraints, simulating equipment connections that are in the immediate vicinity of the hanger are usually freed during the hanger design restrained weight run, so that loads normally going to the equipment nozzle are carried by the hanger. The user should enter the node number for the equipment where the restraint to be freed acts. The corresponding “free code” may also be specified to tell CAESAR II which of the restraint/anchor directions to be freed. For nozzles that are further removed from the hanger usually only the Y direction should be freed. Hangers are commonly used around equipment nozzles to support the weight of the pipe as it thermally expands away from the nozzle. The hanger can usually be designed to take almost the full weight of the pipe between the anchor and the hanger if the anchor is freed when making the restrained weight calculation. The anchor is “freed” by entering its node number in the Free Anchor/Restraint at Node field. The pipe going to the anchor will be treated just like a free end (for the hanger weight calculation only!!!). The Free Code field works with the Free Anchor/Restraint at Node field to limit the actual degrees of freedom at an anchor that are released. The Free Anchor/Restraint at Node field works in conjunction with the Free Code field. If the Free Code is not specified for an anchor, the anchor is assumed to be completely free for the restrained weight run. The “Restrained Weight” hanger design pass is the first analysis step in the hanger design, and is run automatically by CAESAR II. The following steps comprise the “Restrained Weight” run: 1

Putting rigid Y restraints at each hanger location.

2

Removing anchors and restraints that are to be “freed.”

3

Running the weight analysis to find the hot hanger loads.

Note:

Nonlinear restraints may not be freed during hanger design.

Free Code Whenever an anchor or restraint should be released for the restrained weight run, that anchor’s node number should be put in the Free Anchor/Restraint at Node field, and the Free Code describing the directions to be released should be put in the Free Code field on the same hanger spreadsheet. Free Codes are Free the anchor or restraint in the Y direction only. Free the anchor or restraint in the Y and X directions only. Free the anchor or restraint in the Y and Z directions only. Free all translational degrees of freedom for the anchor or restraint. (X,Y and Z) Free all translational and rotational degrees of freedom for the anchor or restraint. (X, Y, Z, RX, RY, and RZ) The last option usually results in the highest adjacent hanger loads, but should only be used when the horizontal distance between the hanger and the anchor is within about 4 pipe diameters.

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Predefined Hanger Data When using the Predefined Hanger Data fields on the hanger spreadsheet, and there is more than one hanger at the location, use the Number of Hangers field to specify the number of hangers. Then enter the spring rate and pre-load applicable to a single hanger. There is no reason to try to compute the equivalent spring rates or theoretical loads. Pre-defined hanger data can be entered in one of two ways: All information for the hanger can be input. Only the spring rate for the hanger can be input. If all information is input, the restraint configuration for the node is completely defined and it will not be included in the hanger design algorithm. For a position to be completely pre-defined, one of the following conditions must apply: spring rate and theoretical cold load constant effort support load

Spring Rate and Cold Load The spring rate and the theoretical cold load effectively define a hanger location. If the user enters both, then the hanger location will be completely pre-defined by the user and no analysis level design for the hanger will take place.

Re-setting Loads on Existing Spring Hangers If only the spring rate is given, CAESAR II will assume that the user wants to re-rate the spring at the given location. The old spring rate should be read from the existing hanger and input directly to CAESAR II. The Theoretical Cold Load field should be left blank for the re-rate. If more than a single spring exists at the location, then the total number of springs should be entered in the No. of Hangers field (CAESAR II assumes that the load is distributed evenly among multiple springs at the same point). CAESAR II will go through its normal hanger design procedure to calculate the load and travel for all proposed hanger locations including the location with springs to be re-set. The stiffness of the re-set springs will not be used for this re-design. Once CAESAR II sizes the springs, a comparison will be made with the user-entered spring rates. If the program's selected spring rate is within 5% of the user's existing spring rate, CAESAR II will list the spring's figure number and size in the output report. If the selected spring rate is more than 5% off the users value, no manufacturer's data will be listed. In either case, CAESAR II will use the user-entered spring rate in all following analyses. It is up to the user to confirm that the new hot and cold loads are within the existing spring's working range. The major use of the re-rate capability is to find new installed loads for old springs. Springs might be rerated after the shutdown of a unit that has been operating continuously for a long period, or after mechanical or process changes have been made to a piping system.

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Nozzles Activate by double-clicking the Nozzles check box on the Pipe Element Spreadsheet and selecting the WRC 297 radio button from the Nozzle Auxiliary Data field. Deactivate by double-clicking a second time.

Nozzle Flexibility - WRC 297 Activate by double-clicking the Nozzles check box on the Pipe Element Spreadsheet and selecting the WRC 297 radio button from the Nozzle Auxiliary Data field. Deactivate by double-clicking a second time.

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When a nozzle node number is input, CAESAR II scans the current input data for the node and loads its diameter and wall thickness and enters it in the Nozzle Auxiliary Data field. Current nozzle flexibility calculations are in accordance with the Welding Research Council Bulletin No. 297, issued August 1984 for cylinder to cylinder intersections. A valid nozzle node has the following properties: Only a single element connects to the nozzle node. The nozzle node is not restrained and does not have displacements specified for any of its degrees of freedom. Computed nozzle flexibilities are automatically included in the piping system analysis via program generated restraints. This generation is completely transparent to the user. Six restraints are established for each flexible nozzle input. If a vessel node number is defined, then the vessel node acts like a connecting node for each of the six restraints. Vessel nodes are subject to the same restrictions shown above for nozzle nodes. Note: The user should not put a restrainer on an element between the nozzle node and any specified vessel node. CAESAR II creates the required connectivity from the nozzle flexibility data and any user generated stiffnesses between these two points will add erroneously to the nozzle stiffnesses. During the error checking of the nozzle flexibilities, all useful WRC curve data is displayed on the terminal. These values may be used to enter the illustrated nozzles in the WRC 297 bulletin. It is sometimes helpful to know just how close a particular nozzle is to one of the several asymptotic limits, or to a curve boundary.

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Note: The user will only be able to see the WRC 297 computed data during the error checking process with warning messages activated. Each input item on the nozzle spreadsheet is discussed in detail as follows:

Nozzle Node Number Node that is located at the nozzle's intersection with the vessel shell. There should only be a single piping element connected to this node, and there should be no restraints acting on the node. The nozzle element should be perpendicular to the vessel shell. Hillside nozzles and latrolets can still be modeled; however, the first (possibly very short) nozzle element that comes from the vessel should be perpendicular to the vessel to keep the local stiffness properly oriented. The second, longer nozzle element can then go off on the true centerline of the nozzle.

Vessel Node Number Node on the vessel/tank surface at the point where the nozzle intersects the vessel shell. The vessel/tank node is optional, and if not given the nozzle node is connected via the stiffnesses to a point fixed rigidly in space. If the vessel node is given, the nozzle node will be connected via the stiffnesses to the vessel node. Vessel nodes are specified when the user wishes to model through the vessel from the nozzle connection to the skirt or foundation.

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Nozzle Diameter Outside diameter of the nozzle. (Does not have to be equal to the diameter of the pipe used to model the nozzle.)

Nozzle Wall Thickness Wall thickness of the nozzle. (Does not have to be equal to the wall thickness of the pipe element used to model the nozzle.)

Vessel Diameter

Outside diameter of the vessel.

Vessel Wall Thickness

Wall thickness of the vessel at the point where the nozzle connects to the vessel. Do not include the thickness of any reinforcing pad.

Vessel Reinforcing Pad Thickness

Thickness of any reinforcing pad at the nozzle. This thickness is added to the vessel wall thickness before nozzle stiffness calculations are performed.

Distance to Stiffener or Head

Distance along the vessel center-line, from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel that significantly stiffens the cross-section of the vessel against local deformation normal to the shell surface.

Distance to Opposite-Side Stiffener or Head

Distance from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel on the other side of the nozzle. This entry is ignored for spherical vessels.

Vessel centerline direction vector X, Y, Z Direction vector or direction cosines which define the center-line of the vessel. For a vertical vessel this entry would read: Vessel centerline direction vector X: Vessel centerline direction vector Y:

1.0

Vessel centerline direction vector Z:

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CAESAR II Technical Reference Manual

Note:

The centerlines of the nozzle and vessel cannot be collinear or CAESAR II will flag this as an error.

Vessel Temperature (Optional)

Estimated temperature of the vessel/nozzle junction. If input, the vessel temperature must be paired with a valid vessel material number. The estimated temperature is used to calculate the hot modulus of elasticity.

Vessel Material No. (Optional) If input, the vessel material number must be paired with a valid vessel temperature. The allowed vessel material number can be any valid material number from the material database and corresponds to the pipe materials used in the spreadsheet. If the vessel temperature and the vessel material number are left blank or zero, an elastic modulus of 29.0E6 psi will be used.

API 650 NOZZLES Activate by double-clicking the Nozzles check box on the Pipe Element Spreadsheet and selecting the API 650 radio button from the Nozzle Auxiliary Data field. Deactivate by double-clicking the check box a second time.

CAESAR II can also calculate nozzle flexibilities according to appendix P of API 650, "Design of Carbon Steel Atmospheric Oil Storage Tanks."

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Nozzle Node Number Node that is located at the nozzle's intersection with the vessel shell. There should only be a single piping element connected to this node, and there should be no restraints acting on the node. The nozzle element should be perpendicular to the vessel shell. Hillside nozzles and latrolets can still be modeled; however, the first (possibly very short) nozzle element that comes from the vessel should be perpendicular to the vessel to keep the local stiffness properly oriented. The second, longer nozzle element can then go off on the true centerline of the nozzle. Tank Node Number Node on the tank surface at the point where the nozzle intersects the vessel/tank shell. The tank node is optional, and if not given the nozzle node is connected via the API stiffnesses to a point fixed rigidly in space. If the tank node is given, the nozzle node will be connected via the API stiffnesses to the tank node. Tank nodes are specified when the user wishes to model through the tank from the nozzle connection to the foundation. Nozzle Diameter

Outside diameter of the nozzle. (Does not have to be equal to the diameter of the pipe used to model the nozzle.) Nozzle Wall Thickness

Wall Thickness of the nozzle. May be different than the attached pipe wall thickness API-650 Tank Diameter

Outside Diameter of the Vessel or API 650 storage tank. Note that API 650 Addendum 1 does not recommend these computations for diameters less than 120 feet. API-650 Tank Wall Thickness

Wall Thickness of the Vessel at the point where the Nozzle connects to the vessel. DO NOT include the thickness of any reinforcing pad. API 650 Reinforcing 1 or 2 For API tanks, if the reinforcing is on the shell, then enter 1. If it is on the nozzle, enter a 2. API 650 Nozzle Height

For API 650 applications, enter the height from the centerline of the nozzle to the base of the tank.

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CAESAR II Technical Reference Manual API 650 Fluid Height

Enter the liquid level of the fluid in the storage tank. This fluid level must be greater than the nozzle height. API 650 Specific Gravity Enter the specific gravity of the stored liquid. This value is unitless. API-650 Tank Coefficient of Thermal Expansion

Enter the coefficient of thermal expansion of the plate material of the tank is constructed. Values are listed in engineering handbooks or the appropriate section of the API 650, App P. If this value is left blank, zero will be assumed. API 650 Delta T

Enter the change in temperature from ambient to its maximum that the tank normally experiences. For example: If the maximum summertime temperature is 107°F. The delta T would be 107 - 70 = 37°F. If this value is left blank, zero will be assumed. API-650 Tank Modulus of Elasticity

For API 650 nozzles, the hot modulus of elasticity of the tank must be entered directly. If this value is left blank, 29.5E6 will be assumed.

PD 5500 Nozzles Activate by double-clicking the Nozzles check box on the Pipe Element Spreadsheet and selecting the PD 5500 radio button from the Nozzle Auxiliary Data field. Deactivate by double-clicking the check box a second time.

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CAESAR II can also calculate nozzle flexibilities according to Appendix G of the PD 5500 Specification for Unfired Fusion Welded Pressure Vessels. The input requirements for these nozzles are: Nozzle Node Number Node that is located at the nozzle's intersection with the vessel shell. There should only be a single piping element connected to this node, and there should be no restraints acting on the node. The nozzle element should be perpendicular to the vessel shell. Hillside nozzles and latrolets can still be modeled; however, the first (possibly very short) nozzle element that comes from the vessel should be perpendicular to the vessel to keep the local stiffness properly oriented. The second, longer nozzle element can then go off on the true centerline of the nozzle. Vessel Node Number Node on the vessel/tank surface at the point where the nozzle intersects the vessel shell. The vessel/tank node is optional, and if not given the nozzle node is connected via the stiffnesses to a point fixed rigidly in space. If the vessel node is given, the nozzle node will be connected via the stiffnesses to the vessel node. Vessel nodes are specified when the user wishes to model through the vessel from the nozzle connection to the skirt or foundation. Vessel Type - Cylinder (0) or Sphere (1) If the vessel is cylindrical, enter a 0. For cylinders, the distances to stiffeners/heads and the vessel direction cosines are required. If the vessel is spherical, enter a 1. For spheres, the fields for the distances to stiffeners/heads and vessel direction cosines are both ignored. Nozzle Diameter

Outside diameter of the nozzle. (Does not have to be equal to the diameter of the pipe used to model the nozzle.)

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CAESAR II Technical Reference Manual Vessel Diameter

Outside diameter of the vessel. Vessel Wall Thickness

Wall thickness of the vessel at the point where the nozzle connects to the vessel. Do not include the thickness of any reinforcing pad. Vessel Reinforcing Pad Thickness

Thickness of any reinforcing pad at the nozzle. This thickness is added to the vessel wall thickness before nozzle stiffness calculations are performed. Distance to Stiffener or Head

Distance along the vessel center-line, from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel that significantly stiffens the cross-section of the vessel against local deformation normal to the shell surface. Distance to Opposite-Side Stiffener or Head

Distance from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel on the other side of the nozzle. This entry is ignored for spherical vessels. Vessel Centerline Direction Cosines These are direction vectors or direction cosines that define the center-line of the vessel. For a horizontal vessel aligned with the “X” axis, this entry would read: Vessel centerline direction vector X ..... 1.0 Vessel centerline direction vector Y ..... Vessel centerline direction vector Z ..... Note: The centerlines of the nozzle and vessel cannot be co-linear or CAESAR II will flag this as an error. This entry is ignored for spherical vessels. Vessel Temperature (Optional)

Estimated temperature of the vessel/nozzle junction. If input, the vessel temperature must be paired with a valid vessel material number. The estimated temperature is used to calculate the hot modulus of elasticity.

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Vessel Material No. (Optional) If input, the vessel material number must be paired with a valid vessel temperature. The allowed vessel material number can be any valid material number from the material database and corresponds to the pipe materials used in the spreadsheet. If the vessel temperature and the vessel material number are left blank or zero, an elastic modulus of 29.0E6 psi will be used.

Displacements

Activate by double-clicking the Displacements check box on the Pipe Element Spreadsheet. Deactivate by double-clicking the Displacements check box a second time.

Enter the node number where the displacement is to be specified. There must not be a restraint at this node. Enter the displacements at the node. Any displacement direction not specified for any displacement vector will be free. To specify an anchor at node 1000 with a 1/2-in. displacement in the minus Y direction for displacement set #1, enter data as shown in the figure above. The displacements at a node can be specified for up to 9 different vectors, intended to correspond to the 9 temperature cases. Note: If an imposed displacement is specified for a specific degree-of-freedom, that degree-of-freedom will be considered restrained for all load cases whether or not they contain that displacement set.

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Auxiliary Fields - Imposed Loads Forces and Moments Activate by double-clicking the Forces/Moments check box on the Pipe Element Spreadsheet. Deactivate by double-clicking the check box a second time.

Enter the node number where the forces and/or moments are to act. Enter the magnitudes of the forces and/or moments. Up to 9 different force vectors can be defined at each node point.

Uniform Loads Activate by double-clicking the Uniform Loads check box on the Pipe Element Spreadsheet. Deactivate by double-clicking the check box a second time.

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The uniform load specification is distributive, and will act on all following elements until zeroed or changed. A snow load of 8.0 pounds per foot (assuming units of pounds per inch) could be entered: Vector 1 Vector 2 Vector 3 UX UY

-8/12

UZ

or may be entered: UX UY

-.6667

UZ

UX, UY, and UZ can be changed to GX, GY, and GZ so that uniform loads can be entered as a fraction of the total pipe weight through the Kaux- Special Execution Parameters (see "Uniform Load in G's" on page 112) command. The GX, GY, and GZ specifications are used most frequently for defining static earthquake loadings. Note:

Up to 3 uniform load vectors can be defined.

Wind Loads Activate by double-clicking the Wind/Wave check box on the Pipe Element Spreadsheet. Deactivate by double-clicking the check box a second time.

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CAESAR II Technical Reference Manual

This is a shape factor as defined in ASCE #7. A value of 0.5 to 0.65 is typically used for cylindrical sections. Activating the wind directive will enable the Wind Load Input Spreadsheets, which are accessed from the Load Case Editor during the Static Analysis. This auxiliary is used to define the presence of wind loads (via the wind shape factor as defined in ASCE #7) or wave loads (with associated coefficients). The load type may be set or turned off via the radio button. Important: off.

This value is distributive, and will act on all following elements until changed or turned

Wind Shape Factor Coefficient defined in A58.1-1982 in Table 12 for chimneys, tanks, and similar structure. A value of 0.5 to 0.65 is typically used for cylindrical sections. Activating the wind directive will turn on the Wind Load Input Spreadsheets, which are accessed form the Load Case Editor during Static Analysis. Activate by double clicking the Wind Wave checkbox on the Pipe Element SPreadsheet. Deactivate by double clicking the checkbox a second time.

Wave Loads Activate by double-clicking the Wind/Wave check box on the Pipe Element Spreadsheet. Deactivate by double-clicking the check box a second time.

Important: turned off.

These values are distributive, and will act on all following elements until changed or

Drag Coefficient, Cd Coefficient as recommended by API RP2A. Typical values range from 0.6 to 1.20. Entering a 0.0 instructs CAESAR II to calculate the drag coefficient based on particle velocities.

Added Mass Coefficient, Ca This coefficient accounts for the added mass of fluid entrained into the pipe. Typical values range from 0.5 to 1.0. Entering a 0.0 instructs CAESAR II to calculate the added mass coefficient based on particle velocities.

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61

Lift Coefficient, Cl This coefficient accounts for wave lift, which is the force perpendicular to both the element axis and the particle velocity vector. Entering a 0.0 instructs CAESAR II to calculate the added lift coefficient based on particle velocities.

Marine Growth

The thickness of any marine growth adhering to the external pipe wall. This will increase the pipe diameter experiencing wave loading by twice this value.

Marine Growth Density

An entry in this field designates the density to be used if including the weight of the marine growth in the pipe weight. If left blank, the weight of the marine growth will be ignored.

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Auxiliary Fields - Piping Code Data Allowable Stresses Activate by double-clicking the Allowable Stresses check box on the Pipe Element Spreadsheet. Deactivate by double-clicking the check box a second time.

The Allowable Stress Auxiliary field incorporates piping codes with their associated inputs. The help screens should be used liberally to be sure that the proper interpretation of each new input data cell is made. A CAESAR II Piping Spreadsheet illustrating the Allowable Stress field is shown above. Note: Allowable stress data is distributive, and applies to all following elements unless changed or zeroed.

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63

Codes The piping codes are listed in the following table. Their current publication dates can be found in the CAESAR II Quick Reference Guide.

B31.1

Swedish Power Piping Code (Method 1)

B31.3

Swedish Power Piping Code (Method 2)

B31.4

B31.1 - 1967

B31.4, Chapter IX

Stoomwezen

B31.5

RCC-M C

B31.8

RCC-M D

B31.8, Chapter VIII

CODETI

B31.11

Norwegian TBK-6

ASME Sect III NC (Class 2)

FDBR

ASME Sect III ND (Class 3)

BS 7159

Navy 505

UKOOA

CAN/CSA Z662

IGE/TD/12

BS 806

DNV

Each of the input data cells are discussed in general in the following section. For more information about code compliance consideration see Chapter 6 of the Technical Reference Manual.

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CAESAR II Technical Reference Manual

SC

Typically the cold allowable stress for the specific material taken directly from the governing piping code. The value of SC will usually be divided by the longitudinal weld efficiency (Eff) before being used. See the notes that follow for the specific piping code. B31.1. Allowable stress tables in Appendix A include the longitudinal weld joint efficiencies where applicable. These efficiencies should not be used for flexibility stress calculations. If the joint efficiency (Eff) is given on this spreadsheet CAESAR II will divide the entered SC by the joint efficiency before using it in the allowable stress equations. B31.3. Values from tables in Appendix A don’t include the joint efficiency. Eff should be zero, blank, or one. Note that the 1980 version of B31.3 included the longitudinal weld joint efficiencies as part of the tables in Appendix A. If this version of the code is being used then Eff should be entered in the appropriate field on this spreadsheet. B31.4, B31.4 Chapter IX. SC is not used!!! The only stress value in B31.4 is the yield stress taken from Table 1 in the appendix. (See the Sy data field on this spreadsheet.) B31.5. Values from tables in Appendix A don’t include the joint efficiency. Eff should be zero, blank, or one. B31.8, B31.8 Chapter VIII. SC is not used!!! The only stress value in B31.8 is the yield stress taken from Appendix D. (See the Sy data field.) B31.11. SC is not used!!! The only stress value used in B31.11 is the yield stress. ASME NC and ND. SC is taken directly from Appendix I. “Eff” is not used, and is ignored if entered. Navy 505. There is no mention of joint efficiency in the 505 specification; however, it is implied in Footnote 1 of Table TIIA. If a joint efficiency is given CAESAR II will divide SC by the joint efficiency before using it in the allowable stress equations. Eff should probably be zero, blank, or one. CAN Z662. SC is not used. The only stress value in Z184 is the yield stress specified in the standards or specification under which the pipe was purchased. (See the Sy data field.) BS 806. 0.2% of the proof stress at room temperature from Appendix E. “Eff” is not used in BS 806 and is ignored if entered. Swedish Method 1. SC is not used. Method 1 only uses either the yield, or creep rupture stress at temperature, (SHn and Fn respectively on this spreadsheet.) “Eff” is used, but is the Circumferential weld joint efficiency and has a completely different meaning. Swedish Method 2. SC is the allowable stress at room temperature from Appendix 2. “Eff” is not used, and is ignored if entered. B31.1 (1967). SC is the allowable stress at room temperature from the tables in Appendix A. These tables include the Longitudinal Weld joint efficiencies where applicable. These efficiencies should not be used for flexibility stress calculations. If the joint efficiency “Eff” is given CAESAR II will divide the entered SC by the joint efficiency before using it in the allowable stress equations. Stoomwezen (1989). SC is the yield stress at room temperature, referred to as Re in the code.

Chapter 3 Piping Screen Reference

RCC-M C, D. SC is taken from Appendix, “Eff” is not used, and is ignored if entered. CODETI. This is "famb" from the code. “Eff” is not used, and is ignored if entered. Norwegian. This is "f1" from the code. “Eff” is not used for longitudinal joint efficiency. BS 7159. SC is not used. Design stress is entered in the SH fields. UKOOA. SC is not used. Design stress (in the hoop direction) is entered in the SH fields. IGE/TD/12. SC is not used. DNV. SC is not used.

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CAESAR II Technical Reference Manual

SH

Typically the hot allowable stress for the specific material taken directly from the governing piping code. A value must be entered for each defined temperature case. The value of SH will usually be divided by the longitudinal weld efficiency (Eff) before being used. See the recommendations that follow for the specific piping code. B31.1. Allowable stress from Appendix A, see SC above. B31.3. Allowable stress from Appendix A, see SC above. B31.4, B31.4 Chapter IX . SH is not used. B31.5. Allowable stress from Appendix A, see SC above. B31.8, B31.8 Chapter VIII . SH is used for the minimum wall thickness computations only. B31.11.. SH is not used. ASME NC and ND. Allowable stress from Appendix I. Navy 505. Allowable stress from Table XIIA. See SC above. CAN Z662. SH is not used. BS 806. SH is 0.2% of the proof stress at design temperature Appendix E. (Eff is not used.) Swedish Method 1. SH is the yield stress at temperature from Appendix 1. Swedish Method 2. SH is the allowable stress at temperature from Appendix 2. B31.1 (1967). Allowable stress from Appendix A, see SC above. Stoomwezen. SH is the yield stress at design temperature, referred to as Re (um) in the code. RCC-M C, D. SH is taken from the Appendix. CODETI. This is “f” from the code. Norwegian. This is “"f2” from the code. FDBR. The hot allowable defined in Section 3.2. BS 7159. This is the design stress d, in the longitudinal direction, as defined in Section 4.3 of the code, i.e.: d = d * Elamx. Design stress in the circumferential (hoop) direction should be specified by entering the ratio of the circumferential design stress to the axial design stress in the Eff field below. (Note that since design strain should be the same for both directions, the entry in the Eff field will also be ratio of Elamf(hoop) to Elamx (longitudinal). UKOOA. This is the allowable design stress in the hoop direction, defined in the code as f1 * LTHS. The three “HOT ALLOWABLE STRESS” fields correspond to the three possible temperature cases.

Chapter 3 Piping Screen Reference

IGE/TD/12. Yield Stress is used here instead of a Hot Allowable Stress.

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Fn STRESS RANGE REDUCTION FACTOR Note: Unless explicitly entered by the user, this value will be taken from the material database, if available and applicable. STRESS RANGE REDUCTION FACTOR for most piping codes. Exceptions are noted below. In most cases the stress range reduction factor is taken from the following tables: B31.3

B31.1 OPERATING

REDUCTION

OPERATING

REDUCTION

CYCLES

FACTOR

CYCLES

FACTOR

7000 and less

1.0

7000 and less

1.0

7000 - 14000

0.9

7000 - 14000

0.9

14000 - 22000

0.8

14000 - 22000

0.8

22000 - 45000

0.7

22000 - 45000

0.7

45000 - 100000

0.6

45000 - 100000

0.6

100000 -

0.5

100000 - 200000

0.5

200000 - 700000

0.4

700000 - 2000000

0.3

Where several thermal states exist and where the number of thermal cycles is high the user should consult the applicable B31 piping code for methods of combining cycle life data. If omitted a value of ONE will be used.

EXCEPTIONS: B31.4 - Not Used !!!! B31.8 - Not Used !!!! B31.8 CHAPTER VIII - Not Used !!!! CODETI - This term is called "U" in the code. NORWEGIAN - This term is called "fr" in the code, and may be as high as 2.34. DNV - This is the material ultimate tensile strength at temperature. CAN Z662 - F1 = L, the location factor, obtained from Table 4.1

Chapter 3 Piping Screen Reference

Application

CLASS 1

CLASS 2

CLASS 3

CLASS 4

General & cased crossings

1.000

0.900

0.700

0.550

Roads

0.750

0.625

0.625

0.500

Railways

0.625

0.625

0.625

0.500

Stations

0.625

0.625

0.625

0.500

Other

0.750

0.750

0.625

0.500

General & cased crossings

0.900

0.750

0.625

0.500

Roads

0.750

0.625

0.625

0.500

Railways

0.625

0.625

0.625

0.500

Stations

0.625

0.625

0.625

0.500

Other

0.750

0.750

0.625

0.500

General & cased crossings

1.000

0.800

0.800

0.800

Roads

0.800

0.800

0.800

0.800

Railways

0.625

0.625

0.625

0.625

Stations

0.800

0.800

0.800

0.800

Other

0.800

0.800

0.800

0.800

Uncased railway crossings

0.625

0.625

0.625

0.625

All others

1.000

1.000

1.000

1.000

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Gas (non-sour)

Gas (sour service)

HVP

LVP

Class 1 - Location areas containing 10 or fewer dwelling units intended for human occupancy Class 2 - Location areas containing 11 to 46 dwelling units intended for human occupancy OR buildings with more than 20 persons outside areas with more than 20 persons industrial installations Class 3 - Location areas with more than 46 dwelling units intended for human occupancy OR institutions where rapid evacuation may be difficult Class 4 - Location areas where buildings intended for human occupancy have 4 or more stories.

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F2 = T, the temperature derating factor, obtained from Table 4.3 Temperature

Derating Factor T

up to 120 (C)

1.00

150

0.97

180

0.93

200

0.91

230

0.87

F3 - Not Used !!!! BS 806 - Mean Stress to Failure in design life at design temperature. F1, F2, ... F9 correspond to the up-to nine possible thermal states. FDBR - Identical to B31.1, except: Note that if "expansion coefficients" are entered directly instead of temperatures, the program can not determine Ehot. In this case, a value of 1.0 should be entered in the FAC cell and these fields should be used to specify the product of ( f * Ehot / Ecold ) for each temperature case. SWEDISH METHOD 1 - Creep Rupture Stress at temperature. F1, F2 ... F9 correspond to the up-to nine possible thermal states. STOOMWEZEN - Creep related material properties as follows: F1 = Rrg - average creep stress to produce 1% permanent set after 100,000 hours at temperature (vm). F2 = Rmg - average creep tensile stress to produce rupture after 100,000 hours at temperature (vm). F3 = Rmmin - minimum creep tensile stress to produce rupture after 100,000 hours at temperature (vm). BS 7159. The term used in this code is the fatigue factor, Kn, and is used inversely compared to other codes (so its value is greater than 1.0). Kn is calculated as: Kn =

1 + 0.25(As/ n) (log10(n) - 3)

Where: As = n

n

stress range during fatigue cycle

=

Maximum stress during fatigue cycle

=

number of stress cycles during design life

UKOOA. This is the ratio r from the material UKOOA idealized allowable stress envelope. This ratio is defined as sa(0:1)/sa(2:1) as shown on the figure below. One value should be given for each of the operating temperature cases. IGE/TD/12. This is the UTS value.

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Eff The longitudinal weld joint efficiency. The use of this parameter by CAESAR II varies with the piping code. Depending upon code requirements, the allowable stress may be either divided by Eff for use in the flexibility calculations or multiplied by Eff for use in the minimum wall calculations. The following describes the effect of the longitudinal joint efficiency for each of the piping codes. B31.1, B31.1-1967, B31.5. Allowable stress tables include Longitudinal Weld Joint Efficiencies where applicable. If Eff is entered, values for SC and SH will be divided by Eff before being used in the flexibility calculations. Eff will be ignored in the minimum wall calculation. B31.3, B31.4, B31.8, B31.11, NAVY 505, Z662 (J), BS 806 (e), CODETI (z), FDBR (vl). Allowable stress (or yield stress) tables do not include Longitudinal Weld Joint Efficiencies, Eff will be ignored for the flexibility calculations. SH will be multiplied by Eff when calculating the minimum wall thickness. B31.4 Chapter IX, B31.8 Chapter VIII, ASME NC, ASME ND, RCCM-C, RCCM-D. Eff is ignored for both flexibility and minimum wall thickness calculations, and therefore the field is disabled for these code. Swedish Method 1, Swedish Method 2, Norwegian TBK 5-6. Eff is the circumferential joint factor z and is used in the calculation of the code stresses, rather than in the calculation of the allowables (either for flexibility or minimum wall thickness). Stoomwezen. For this code, this Eff is the cyclic reduction factor, referred to as Cf in the code. Weld joint efficiency is not considered for this code in CAESAR II. BS 7159. This code replaces this field with Eh/Ea, the ratio of the hoop modulus to the axial modulus of elasticity. If omitted, a default value of 1.0 is used, as though the material is isotropic. UKOOA, IGE/TD/12. These codes replace this field with f2 and Dfac, respectively, the system design factor (typically 0.67). DNV. This code replaces this field with usage factor Ns (pressure yielding) from Tables C1 or C2. The value must be between 0.77 and 0.96.

Sy - Yield Stress at Temperature

This is Syt, the specified minimum yield or stated proof stress of |the pipe material at maximum temperature. Note: Unless explicitly entered by the user, this value will be taken from the Material Database, if available and applicable.

UTS - Ultimate Tensile Strength of Material

This the ultimate tensile strength of the material at design conditions. Note: Unless explicitly entered by the user, this value will be taken from the Material Database, if available and applicable.

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Design Factor (Unitless) This is the system design factor, as described in Table 2 of the IGE/TD/12 code. It should normally fall between 0.3 and 0.67. Note: Unless explicitly entered by the user, this value will |be taken from the material database, if available and applicable.

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73

Sy

This is a code-specific field, generally requiring input only for the transmission and non-US piping codes. Code-specific input requirements are described as follows: B31.1. Not used. B31.3. Not used. B31.4, B31.4 Chapter IX . Taken from Table 1 in the Appendix. B31.5. Used to satisfy the requirements of Paragraph 523.2.2.f.4. This paragraph addresses ferrous materials in piping systems between -20F and -150F. The value entered here should be the quantity (40% of the allowable) as detailed in the Code. When Sy is defined, the OPE case will be considered a "stress case". The allowable reported in the output report will be the value entered here. The computed operating stress will include all longitudinal components, and ignore torsion. B31.8, B31.8 Chapter VIII. Taken from Appendix 5. B31.11. Specified Minimum Yield Stress. ASME Sect III Class 2 and 3. Basic Material Yield Strength at design temperature for use in Eqn. 9 for consideration of Level A and B service limits. Level C and Level D service limits must be satisfied in separate runs by adjusting the value for the occasional factor in the CAESAR II configuration file. If the occasional factor is set to 1.2, the allowable stress is the minimum of 1.2 x 1.5 SH or 1.5 SY. If the factor is 1.5, the allowable is the minimum of 1.5 x 1.5 SH or 1.8 SY, while if the factor is 2.0, the allowable is the minimum of 2.0 x 1.5 SH or 2.0 SY. (Note, in order to satisfy the code SH should be replaced by SM for the latter two.) Navy 505. Not used. CAN Z662. Specified Minimum Yield Strength taken from the standards or specifications under which the pipe was purchased or as per clause 4.3.3. BS 806. Sustained Stress Limit. The lower of 0.8 X 0.2% Proof stress value or the creep rupture design stress value defined in Appendix A under cold or any other operating condition. See 17.2(c) Swedish Method 1. Not Used. The yield stress at temperature is entered in the respective SHn fields for the up to nine possible thermal states. Swedish Method 2. Ultimate Tensile Strength at room temperature. B31.1 (1967). Not used. Stoomwezen (1989). SY is the tensile strength at room temperature, referred to as Rm in the code. RCC-M C, D. Not used. CODETI. Not used.

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Norwegian. This should be the allowable stress at 7000 load cycles, RS, from Code Table 10.2. If not entered, this factor is not considered to control the expansion stress allowable. FDBR. Not used. BS 7159. Not used. UKOOA. Not used. IGE/TD/12. Specified minimum yield stress (SMYS).

Specified Minimum Yield Stress

This is SMYS, or Sy, the specified minimum yield or stated proof stress of the pipe material at room temperature. Note: Unless explicitly entered by the user, this value will be taken from the Material Database, if available and applicable.

Fac A unitless multiplication factor used by some transmission and non-U.S. piping codes. The specific input required for each piping code is discussed as follows: B31.1. Not used. B31.3. Not used. B31.4. Amount the pipeline may be considered under complete axial restraint, i.e. long and buried. This option is used primarily when the user is adding bending stresses to the stresses already developed in the pipeline due to its buried restraint. This condition occurs when, for example a branch is tieing into a long buried header and the soil supports are not modeled. The equation for stress in CAESAR II is: Stress = (Fac) x abs[ E (T2-T1) + (1- ) Shoop ] + (SE + SL)(1-Fac) Where: E = T2 = T1 = = Shoop = SE = SL =

= elastic modulus thermal expansion coefficient per degree operating temperature ambient temperature Poisson' s ratio hoop stress in the pipe. expansion stress due to bending sustained stress due to pressure.

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Fac should be a number between zero and one. One, when the pipe is fully restrained, i.e. buried for a long distance. Zero when the pipe is subject to no buried axial restraint. The default value for Fac is 0.0. Note that when Fac is 0.001, this indicates to CAESAR II that the pipe is buried but that the soil supports have been modeled. This will cause the hoop stress component, rather than the longitudinal stress, to be added to the operating stresses, conforming to the spirit of the restrained line stress calculation above. B31.4 Chapter IX. This value is F1, Hoop Stress Design Factor, as per Table A402.3.5(a) of B31.4. Appropriate values are 0.72 for Pipelines or 0.60 for Platform piping and Risers. B31.5. Not used. B31.8. Construction Design Factor, from Table 841.114B. Construction type: (Descriptions are approx.)

FACTOR

A (CLASS 1) Wasteland, Deserts, Mountains, Grazing Land, Farmland, Sparsely Populated Areas. B (CLASS 2) Fringe Areas Around Cities, Industrial Areas, Ranch or Country Estates.

0.72 0.60

C (CLASS 3) Suburban Housing Developments, Shopping Centers, Residential Areas.

0.50

D (CLASS 4) Multi-Story Buildings are prevalent, Traffic is heavy and where there may be numerous other utilities underground.

0.40

(0.4 is the default if not entered.) B31.8 Chapter VIII. This value is F1, Hoop Stress Design Factor, as per Table A842.22 of B31.8. Appropriate values are 0.72 for Pipelines or 0.50 for Platform piping and Risers. B31.11. Amount the pipeline may be considered to be under complete axial restraint (see discussion under B31.4 above). ASME Sect III, Class 2 and 3. Not used. B31.1 (1967). Not used. Navy 505. Not used CAN Z662. Indicates whether the pipe is restrained (i.e. long or buried) or unrestrained. The equation for pipe under complete axial restraint is: Stress = (Fac) x abs[ E (T2-T1) + (1- ) Shoop ] + (SE + SL)(1-Fac)

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Where: E = T2 = T1 = = Shoop = SE = SL =

= elastic modulus thermal expansion coefficient per degree operating temperature ambient temperature Poisson's ratio hoop stress in the pipe. expansion stress due to bending sustained stress due to pressure.

Fac should be 1.0, 0.0, or 0.001. One, for pipe under complete axial restraint.One, when the pipe is fully restrained, i.e. buried for a long distance. The default value for Fac is 0.0. Note that when Fac is 0.001, this indicates to CAESAR II that the pipe is buried but that the soil supports have been modeled. This causes the hoop stress component, rather than the longitudinal stress, to be added to the operating stresses if the axial stress is compressive. BS806. Not used. Swedish Power Code, Method 1. Sigma(tn) multiplier. Usually 1.5. For prestressed (cold sprung) piping this value should be 1.35. The default used is 1.5. Swedish Power Code, Method 2. Not used. Stoomwezen. This is a constant whose value is either 0.44 or 0.5. Refer to Stoomwezen Section 5.2 for details. RCC-M C, D. Not used. CODETI. Not used. Norwegian. This should be the material ultimate tensile strength at room temperature, RM. If not entered, this factor is not considered to control the expansion stress allowable. FDBR. This cell can be used to over-ride the ratio of Ehot/Ecold, which is automatically determined by CAESAR II. The modulus ratio is used to compute the expansion case allowable stress, based on the material and temperature. Normally, this field can be left blank. However, if desired, a value (greater than zero and less than one) can be entered in this field to over-ride the program determined ratio. To correctly utilize the FBDR code, the user should enter the Hot Modulus in the Elastic Modulus cell of the spreadsheet. CAESAR II will look up the Cold Modulus and compute this necessary ratio. Note that the use of the Hot Modulus in the flexibility analysis is a deviation of FBDR from every other piping code in CAESAR II. Note that if expansion coefficients are entered directly instead of temperatures, the program cannot determine Ecold. In this case, a value of 1.0 should be entered in this cell and the cyclic reduction factor fields should be used to specify the product of ( f * Ehot /Ecold) for each temperature case.

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BS 7159. Mean temperature change multiplier k, as defined in Section 7.2.1 of the code. This should be 0.85 for liquids, 0.8 for gases, and 1.0 for ambient temperature changes. If left blank, this value will default to 1.0. UKOOA. Mean temperature change multiplier k, as defined for the BS 7159 code above. If left blank, this value will default to 1.0. IGE/TD/12. Material shakedown factor Ksd. DNV. Usage factor Nu (pressure bursting) from Tables C1or C2. Values must be between 0.64 and 0.84.

Ksd. (Factor) (Unitless) This is the material shakedown factor described in Table 4 of the IGE/TD/12 code. Typical values are: Carbon Steel:

1.8

Austenitic steel:

2.

Pvar This input is only used for the RCC-M, ASME Sect. III NC and ND, and DNV piping codes, the Swedish Power Piping, and the Norwegian codes: ASME and RCC-M C, D. This is the variance in the pressure between operating and “peak” to be used as the component in equation 9 above that found from B1 * P * Do / 2tn. Do not enter the peak pressure for Pvar, enter the difference between the operating pressure and the peak pressure. Swedish Power Code, Methods 1 & 2. This is BETA for the “Seff” calculation. If not given, “beta” defaults to 10%. Ten percent would be entered as 10.0. Values entered must be between 0.1 and 25.0. Values entered outside of this range will be automatically adjusted to the outer limit of the allowed range. The definition for “beta,” as given in the Swedish piping code in section 5.6.2.1, is the “maximum allowable minus the tolerance as a percentage of the nominal wall thickness.” Stoomwezen. PVAR is the Cm coefficient in the code whose value is usually 1.0. Norwegian. PVAR is the difference between design pressure P (in equation 10.7) and peak pressure Pmaks (in equation 10.8). The table that follows defines when each of these parameters is valid input for the piping code (V) or not required (N). DNV. Usage factor N for equivalent stress check from Table C4. Values must be between 0.77 and 1.00.

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Material Fatigue Curves

Material Fatigue Curve data may be entered here, permitting the evaluation of fatigue load cases and cumulative usage scenarios. Cycle vs. Stress data may be entered for up to eight data points. (Note the IGE/TD/12 provides the opportunity to enter up to five fatigue curves, representing fatigue classes D,E, F, G, and W.) Fatigue evaluations are explicitly specified by IGE/TD/12; CAESAR II offers them as extensions to other codes. The user is also given the option of reading in fatigue curve data from a file, several of which are provided with CAESAR II. Cycle/Stress pairs should be entered in ascending order (ascending by cycles). Stress values should be entered as the allowable Stress Range rather than allowable Stress Amplitude. Fatigue Curves will be considered to be entered using a logarithmic interpolation. Note: Fatigue Curves may also be read in from files, using the Read From File button. Note: Static FATigue cases will be evaluated against the full range of the fatigue curve, while dynamic FATigue cases are assumed to represent amplitudes, and are therefore evaluated against half of the range of the fatigue curve.

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Available Commands Break Command This command is initiated with the Model - Break command. This option is available from the pipe spreadsheet and allows the user to “break” an element into two or more individual elements. The “break” option was designed for situations where: A straight run of pipe between two nodes needs to be broken to insert a restraint, or some other change in properties. A long straight run of pipe needs to be broken into multiple, uniform lengths of pipe with similar support conditions on each length, i.e. a long straight run of rack piping, or a buried run with multiple soil supports at each point in the run. An example “break” screen is shown in the following figure:

The example above illustrates a “single element insert” between the nodes 100 and 110. The node to be inserted is 105 and is 6 ft. from the node 100. If there was some other node in the model with a restraint (or imposed displacements) like the one to be put on the newly generated node 105, then the node identifying that restraint location could be filled in at the line “Get support from Node,” and the restraint would be automatically placed at 105. For multiple inserts in a rack piping system the prompts might appear as follows:

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At the prompt for “support condition” if the user entered the node where a +Y restraint had already been defined, a +Y restraint would be placed at all of the generated nodes, namely 110, 112, ... , 120. The multiple insert BREAK is used primarily for three reasons: Rack piping supports where the total length and node spacing is known and entered directly when requested at the “break” prompts. Underground pipe runs where the overall length of the run is known, and the lengths of the individual elements in the run are known. To add mass points in order to refine a model for dynamic analysis. Note: There are two occasions when “Break” will not work: • The element is an expansion joint. • The delta dimensions in the DX, DY, and DZ fields are blank or zero.

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Valve/Flange Database The Valve and Flange database is accessed through the Model - Valve command. There are four databases currently provided: CRANE steel valves and total flange length GENERIC valves and 2/3 flange length Corner and Lada valves - no flanges CADWorx/PIPE (this is the CAESAR II default) The CRANE database contains all flanged and welded fittings in the CRANE steel valve catalog. The GENERIC database contains information from a variety of sources. In some cases (i.e. weights for control valves) information from different sources was found to vary considerably. In these cases the largest reasonable weight was selected for use in the database. In other cases only the length of the fitting was available. The default database, the CADWorx/Pipe database, is a subset of the full component database provided with CADWorx/Pipe, COADE's piping design and drafting program. This database offers nine different component types (gate, globe, check, control, ball, plug, and butterfly valves; flange pair and single flange) as well as four different end types (flanged, no-flanged, threaded, or socket). Selection of flangedend components or flanges themselves automatically provides for gaskets.

Note: Selecting flanged ends (FLG) for a valve simply adds the length and weight of two flanges and gaskets to the valve length and weight. No FLG selects a valve without including the two mating flanges.

Accessing the valve and flange database. 1

Enter the node numbers for the rigid element in the From and To fields on the pipe spreadsheet.

2

Click the Valve/Flange toolbar or select MODEL - VALVE from the menu.

3

Use the mouse to highlight blocks to select the particular fitting desired.

4

Click OK to accept the selection. If the particular selection is valid for the current line size, the user will see that CAESAR II enters the length of the element in the DX, DY, and/or DZ fields, designates the element as RIGID, and inserts the weight in the appropriate slot in the Auxiliary field.

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The assumed orientation of the rigid is taken from the preceding element. The user should note that CAESAR II is doing a table lookup based on line size, and is inserting the selected table values into the spreadsheet. Should the line size change at some later time, the user must come back and ask CAESAR II to perform another table look-up for the new sizes. Use of the CADWorx/Pipe database offers several benefits over use of the other databases: The CADWorx/Pipe database provides more accurate component lengths and weights than those typically available in the GENERIC database. Using the same component data for CAESAR II and CADWorx/Pipe modeling promotes the efficiency of the bi-directional interface between the two programs, for those who are using both programs. Total sharing of data files and specifications between CAESAR II and CADWorx/Pipe occurs when the CADWorx program installation directive is saved in the registry. In that case, the third line of the CADWORX.VHD file should be edited to name the actual CADWorx specifications (located in the CADWORX\SPEC subdirectory). For more information on editing this file, see below. Users may more easily modify the CADWorx/Pipe valve and flange database, since the specification files and component data files are ASCII text files. This process, which involves possibly editing the CADWORX.VHD, specification, and data files, is described below. The CADWORX.VHD file is structured as such:

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The first line must read CADWORX.DAT, so it may not be changed. The second line, which may be edited by the user, must begin with a zero; the second number on the line designates the number of specifications to make available to the user. It can be a maximum of 7. The third line, which may be edited by the user, lists the available specifications. Each specification name must consist of 8 characters, padded by blanks on the right. The specification names designate files with extension .SPC, located in the SPEC subdirectory of the CAESAR II or the CADWorx/Pipe specification directory (if the CADWORX directive is set in the registry). The fourth line, which may be edited by the user, designates whether each specification uses English or Metric nominal pipe sizes. Seven blanks followed by a 1 indicate English nominals, while seven blanks followed by a 2 indicate metric nominals. The last five lines should not be changed by the user. The specification files are located in the SPEC subdirectory of the CAESAR installation directory. They are designated by the extension .SPC. The specification files correlate pipe size and component with the appropriate data file. Individual lines in the file list the library (subdirectory to the LIB_I or LIB_M directory, depending on whether English or Metric units are in effect), file name (with an extension equal to the library name), range of nominal pipe sizes for which the specified data file applies. Any of these items may be edited by the user; the last item on the line is the component type number, and should not be changed. Other items in the file pertain to CADWorx/Pipe and are not significant to the CAESAR II user. The data files hold the dimensional and weight values. Data files for different types of components hold different types of data; the data columns are labeled. The only data with significance to the CAESAR II user involves the weight and lengths – these may be changed by the user. The following is a typical component data file for weld neck flanges:

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More extensive information on editing of these files can be found in the CADWorx/Pipe User Manual.

Find Distance Click Origin and Current Node to calculate the distance between coordinate (0.0,0.0,0.0) and the TO node of the current element. Click Nodes, and then enter two node numbers to calculate the distance between those two nodes.

Find Element Enter a single node number to find the next element containing that node number (either as a FROM or TO node). Enter two node numbers to find the next element containing BOTH of those node numbers (in either order).

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Global Coordinates Enter absolute (global) coordinates for the start node of each discontiguous system segment. This may be required for three reasons: 1 -- the user may wish to show nodal coordinates in absolute, rather than relative coordinates. 2 -- defining global coordinates for discontiguous segments allow the piping segments to plot in the correct locations, rather than superimposed at the origin. 3 -- if WIND loading is present, it is important that the pipe be given the correct elevation.

Insert Element Selecting BEFORE inserts a new element prior to the current element, with the FROM node equal to the FROM node of the current element. Selecting AFTER inserts a new element following the current element, with the FROM node equal to the TO node of the current element.

Node Increment When generating the FROM and TO nodes for new elements, CAESAR II uses the nodal increment set in CONFIGURE/SETUP. This may be overridden by entering a different value here.

Show Informational Messages Activate the check box to display informational messages upon the conversion of Nominal to Actual diameters, Schedule to Wall Thickness, and Specific Gravity to Density. De-activate the check box to suppress these messages.

Tee SIF Scratchpad Enter the number of the node where you want to evaluate the Stress Intensification Factors.

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Allowed Intersection / Joint Types ID

Type

sif calculations:

------------------------------------------------------------1 - Reinforced Fabricated Tee

PAD T, FTG ro, CROTCH

....

2 - Unreinforced Fabricated Tee

....

FTG ro, CROTCH

....

3 - Welding Tee

....

FTG ro, CROTCH

....

4 - Sweepolet (Welded-in Contour)

....

....

CROTCH

....

5 - Weldolet

....

....

CROTCH

....

FTG ro, CROTCH

....

(Branch Welded-on)

6 - Extruded Welding Tee

....

7 - Girth Butt Weld

....

....

....

WELD d

8 - Socket Weld (No Undercut)

....

....

....

FILLET

9 - Socket Weld (As Welded)

....

....

....

FILLET

10 - Tapered Transition

....

....

....

WELD d

11 - Threaded Joint

....

....

....

....

12 - Double Welded Slip-on Flange

....

....

....

....

13 - Lap Joint Flange (B16.9 Stub)

....

....

....

....

14 - Bonney Forge Sweepolet

....

....

....

15 - Bonney Forge Latrolet

....

....

....

16 - Bonney Forge Insert Weldolet

....

FTG ro

....

PAD T, FTG ro

....

17 - Full Encirclement Tee

WELD ID .... WELD ID ....

The "TYPE" only needs to be entered once for each intersection or joint in the problem. Users CANNOT specify two different SIFs at a single node and get an increased SIF. For example a socketweld TYPE and an intersection TYPE cannot be specified at the same point. Intersection SIFs can be calculated for one, two or three pipe junctions. Conservative assumptions are made with regard to missing information and orientations. Warning messages are printed during error checking for each intersection where assumptions must be made to apply code rules. For 2 element joints the largest diameter and the smallest thickness are used when discrepancies exist between the two adjoining pipes, (unless the two element fitting is a socket weld, and then the largest thickness is used). These selections are made to generate the largest SIFs and thus the most conservative stress calculations. Intersection SIFs can be calculated for dummy leg intersections on bend curvatures. This is a crude method for estimating bend/dummy leg SIFs, but is often considered an improvement over an unintensified dummy leg.

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Code calculated bend stress intensification factors will always take precedence over any other SIF that may be defined at the bend node. (A setup file directive: ALLOW_USERS_BEND_SIF=YES permits the user to override code sif's at bends if necessary.)

Pad Thickness Thickness of the REINFORCING PAD for reinforced fabricated tees, Intersection type 1. Note: In most piping codes this beneficial effect of the pad's thickness is limited to pads of a thickness less than 1.5 times the nominal thickness of the fitting. This factor does not apply in BS806 or Z662, and is 2.5 in the Swedish piping code. Crotch Thickness for B31.3 Welding Tees and Sweepolets (intersection types 3 and 4). The crotch thickness and radius are necessary for CAESAR II to determine if the fitting meets B16.9 requirements.

Fitting Outside Radius The largest fitting outside radius for branch connections. Used for reduced branch connections in the ASME and B31.1 piping codes, Bonney Forge Insert Weldolets, and for WRC329 intersection SIF calculations. SETUP file directions allow these calculations to be incorporated into most piping codes as an option. SETUP file directives also exist to limit the application of the reduced branch connection rules to UNREINFORCED FABRICATED TEES, SWEEPOLETS, WELDOLETS and EXTRUDED WELDING TEES. (i.e. omitting REDUCED WELDING TEES and REDUCED REINFORCED FABRICATED TEES.) If omitted, FTG ro defaults to the outside radius of the branch connection if omitted.

Crotch Radius CROTCH RADIUS for extruded welding tees, intersection type 6. This is also the intersection weld crotch radius for WRC329. Specifying this value when it is known can result in a 50% reduction in the stress intensification at the intersection. This reduction only applies when WRC329 intersection options are selected from the setup file, and for unreinforced fabricated tees, sweepolets, weldolets and extruded welding tees, i.e. intersection types 2, 4, 5, and 6. This value must be larger than Tb/2 and Th/2 to be effective |in reducing the stress intensification. (There is another value in the code that must be checked by the user and that is (Tb'+y)/2 (y) is the largest thickness at the intersection. The crotch radius must be larger than this value also.) If this value is left blank, a value of zero will be used. This indicates no crotch, i.e. a corner.

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Weld ID Values: 0 or BLANK - As Welded 1

- Finished/Ground Flush

Used for: BONNEY FORGE SWEEPOLETS BONNEY FORGE INSERT WELDOLETS BUTT WELDS IN THE SWEDISH PIPING CODE If entered as 1 then the weld is considered to be ground flush on the inside and out and the sif is taken as 1.0. See the help screens for Weld Mismatch (Weld d) for more detail on how input parameters are used to compute sif's for girth butt welds.

Weld d (Mismatch) Average circumferential weld mismatch measured at the inside diameter of the pipe. Used for Butt Welds and Tapered Transitions. Note: THIS IS THE AVERAGE, AND NOT THE MAXIMUM MISMATCH. USERS MUST VERIFY THAT ANY MAXIMUM MISMATCH REQUIREMENTS ARE SATISFIED FOR THEIR PARTICULAR CODE. This value is used in the sif equations as follows: For B31.1: IF( TR.GE. 0.237 .AND. DMIS/TR .LE. 0.13 ) THEN S = 1.0 ELSE IF( TR .LT. 0.237 .AND. DMIS/TR .LE. 0.33 ) THEN S = 0.9 + 2.7*DMIS/TR IF( S .GT. 1.9 ) S = 1.9 IF( S .LT. 1.0 ) S = 1.0 ELSE IF( TR .GE. 0.237 ) THEN S = 0.9 + 2.7*DMIS/TR IF( S .GT. 1.9 ) S = 1.9 IF( S .LT. 1.0 ) S = 1.0 ELSE OUT OF THE RANGES FOR B31.1 USE THE MAX. SIF S = 1.9

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END IF Where TR is the pipe thickness (inches), and DMIS is the entered weld mismatch. See Table D1 in the B31.1 appendix for a further discussion and assumptions. For B31.3, B31.4, B31.8 (including Ch VIII), BS 806, Canadian, Navy and B31.1-1967: The sif for girth butt welds is always taken as 1.0 regardless of the input for thickness and mismatch. For ASME III NC or ND codes: IF( TR .GE. 0.237 ) THEN S = 1.0 ELSE S = 0.9 * ( 1.0 + 3.0*DMIS/TR ) IF( S .GT. 1.9 ) S = 1.9 IF( S .LT. 1.0 ) S = 1.0 END IF For the Swedish and Norwegian codes: IF( TR .GT. 4.5mm .AND. DMIS/TR .LE. 0.1 ) THEN S = 1.0 ELSE IF( TR.LE.0.1771654 .OR. DMIS/TR.GT.0.1 ) THEN S = 1.8 ELSE IF NONE OF THE OTHER PARAMETERS GOVERN THEN USE A MAX. SIF OF 1.8. Not sure what the code's intention is when none of the above parameters apply. This is certainly the most conservative. S = 1.8 END IF For the RCC-M C/D codes: IF( TR .GT. 4.75mm .AND. DMIS/TR .LE. 0.1 ) THEN S = 1.0 ELSE S = 1.8 END IF For the CODETI code: IF( TR .GT. 5.0mm ) THEN S = 1.0 ELSE

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S = 1.8 END IF For the FDBR code: IF( TR .GT. 5.0mm .AND. DMIS/TR .LE. 0.1 ) THEN S = 1.0 ELSE S = 1.8 END IF For Tapered Transitions this value is the mismatch of the inside diameters at the small end weld, and is used as the "delta" in the equation: sif = 1.3 + 0.0036(d/t) + 3.6("delta")/t

Socket Fillet Weld Leg Length This parameter is used when calculating SIFs of socket welds (type 8 or 9) when the B31.3, ASME-III Subsection NC or ND codes (3, 12, or 13) are in effect. Note: If a fillet leg size is entered, both socket weld types result in the same sif. The sif is calculated as (2.1)(T) / Leg, where T is the pipe wall thickness and Leg is the fillet leg length. A minimum sif of 1.3 required. For an unequal leg fillet weld, use the length of the shorter leg.

Header Pipe Outside Diameter Enter the actual outside diameter of the matching pipe. If the fitting is a taper (TYPE = 10), enter the actual outside diameter of the small end of the tapered connection. Do not enter the fitting diameter.

Header Pipe Wall Thickness Enter the actual wall thickness of the header matching pipe. If the fitting is a taper (TYPE = 10), enter the wall thickness of the small end of the tapered connection. Do not enter the fitting thickness.

Branch Pipe Outside Diameter Enter the actual outside diameter of the matching pipe. Do not enter the diameter of the fitting.

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Branch Pipe Wall Thickness Enter the actual wall thickness of the matching pipe. Do not enter the wall thickness of the fitting.

Bend SIF Scratchpad Bend Radius The Default is LONG RADIUS. The user may override the program calculated bend radius at any time. The long radius bend value is obtained from a look-up table based on the user's specified diameter. Users of pipes with diameters not listed as standard CAESAR II nominal diameters should compute and enter the bend radius by hand. CAESAR II's "ON-SCREEN-MULTIPLICATION" simplifies this chore, i.e. the bend radius for a three-eighths inch pipe could be entered: .375*1.5.

Bend Type/Laminate Type Enter the number of bend end cross sections that resist ovalization, i.e. 0, 1 or 2. A bend's end cross section resists ovalization whenever a much heavier fitting (i.e. a valve or a flange), is attached to the bend end. This entry serves only to modify the stiffness and stress intensification factors for the bend. Flanges stiffen the bend and make it less susceptible to stress. The British Piping Code BS 806 defines a bend's end cross section as resisting ovalization whenever a rigid fitting is within two diameters of the bend's end. For the BS 7159 and UKOOA codes, this entry refers to the material laminate type, and may be 1, 2, or 3. These laminate types are: 1 - All chopped strand mat (CSM) construction with internal and external surface tissue reinforced layer 2 - Chopped strand mat (CSM) and woven roving (WR) construction with internal and external surface tissue reinforced layer 3 - Chopped strand mat (CSM) and multi-filament roving construction with internal and external surface tissue reinforced layer. Laminate type affects the calculation of flexibility factors and stress intensification factors for the BS 7159 and UKOOA codes only.

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Fitting Thickness Enter the thickness of the bend if different than the thickness of the matching pipe. If the entered thickness is greater than the matching pipe wall thickness, then the inside diameter of the bend will be smaller than the inside diameter of the matching pipe. Section modulus calculations for stress computations are made based on the properties of the matching pipe as defined by the codes. The pipe thickness is used twice when calculating SIFs and flexibility factors -- once as Tn, and once when determining the mean cross-sectional radius of the pipe in the equation for the flexibility characteristic (h): h = (Tn)(R) / (r2) Tn = Thickness of bend or fitting R = Bend radius r = Mean cross-sectional radius of matching pipe = (OD - WT) / 2 OD = Outside Diameter of matching pipe WT = Wall Thickness of matching pipe

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Most codes use the actual thickness of the fitting (this entry) for Tn, and the wall thickness of the matching pipe for the calculation of the mean cross-sectional radius of the pipe (the WT value). More specifically, the individual codes use the two wall thicknesses as follows: For Tn:

For Mean Radius

B31.1

Fitting

Fitting

B31.3

Fitting

Matching Pipe

B31.4

Fitting

Matching Pipe

B31.5

Fitting

Matching Pipe

B31.8

Fitting

Matching Pipe

B31.8 Ch VIII

Fitting

Matching Pipe

SECT III NC

Fitting

Matching Pipe

SECT III ND

Fitting

Matching Pipe

Z662

Matching Pipe

Matching Pipe

NAVY 505

Fitting

Fitting

B31.1 (1967)

Fitting

Fitting

SWEDISH

Fitting

Matching Pipe

BS 806

N/A

N/A

STOOMWEZEN

N/A

N/A

RCC-M C/D

Matching pipe

Matching Pipe

CODETI

Fitting

Fitting

NORWEGIAN

Fitting

Fitting

FDBR

Fitting

Fitting

BS 7159

Fitting

Fitting

UKOOA

Fitting

Fitting

IGE/TD/12

Fitting

Fitting

Calculation:

The bend fitting thickness (FTG) is always used as the pipe thickness in the stiffness matrix calculations; however, note that the thickness of the matching pipe (WT) is always used in the bend stress calculations.

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Miter Points Number of CUTS (or changes of direction) in the mitered bend. The "NUMBER OF CUTS" and the "BEND RADIUS" are the only inputs required (along with the program-determined bend angle) to calculate the SIFs and flexibilities defined in the various piping codes for mitered elbows. The RADIUS of the bend and the spacing of the cuts are directly related to one another, given one, the other can be calculated. Closely spaced miters typically have a radius equivalent to the standard long radius bend for the given pipe size. Closely spaced mitered bends, regardless of the number of miter cuts can be modelled as a single bend element. Widely spaced mitered bends should be modelled as "n" single cut miters, where "n" is the number of cuts in the bend. This means that "n" bend elements should be defined, each one a single cut miter. The bend radius associated with these individual, single cut miters is smaller than the standard long radius bend and must be calculated separately. Examples in the CAESAR II User Guide illustrate this application.

Matching Pipe Outside Diameter Enter the outside diameter of the matching pipe in the units shown. This is used in the average cross sectional radius calculation: r2 = (OD - WT) / 2 OD = Outside Diameter as entered WT = Wall Thickness of attached pipe The B31.3 (1993) code defines r2 as the "mean radius of matching pipe".

Wall Thickness of Matching Pipe Enter the actual matching pipe nominal wall thickness. Do not subtract out any corrosion. All SIF calculations are made ignoring corrosion. This wall thickness is used in the mean radius (r2) calculation as defined in the piping codes.

Elastic Modulus Enter the Cold Modulus of Elasticity of the pipe material. This is used for the pressure stiffening calculations.

Maximum Pressure This is used for the pressure stiffening calculations. For the BS 7159 or UKOOA codes, this entry should be the product of the material Design Strain, €, and the material modulus of elasticity.

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Expansion Joint Modeler CAESAR II will automatically generate an expansion joint model from catalog data selected by the user. The catalog used may be selected in the CAESAR II Configure/Setup routine. The user decides where in the model the expansion joint should go, i.e. between which two nodes, and the modeler assembles the completed joint. Selectable joint styles include Untied, Tied, Hinged, Gimballed, Untied-Universal, and Tied Universal expansion joints. An example selection session is illustrated as follows. Of particular note are the following items: Any of four material types may be selected. These material types are used to adjust the bellows stiffnesses to the actual highest temperature in the model. This will typically result in higher stiffnesses than those shown in the vendor’s catalog because the stiffnesses in the catalog may be based on a higher design temperature. Any combination of end types may be selected. Bellows, liner, cover, rod, and hinge/gimbal assembly weights are looked up from the stored database and automatically included in the expansion joint model. For universal joints, the minimum allowed length is stored, but when the available space exceeds the minimum allowed, the user is prompted for the length that he wishes the expansion joint assembly to occupy. The last screen that follows shows the “proposed” model to the user before it is inserted into the CAESAR II input. This allows the user to investigate the characteristics of several joints before settling on one. Actual maximum pressure ratings are also a part of the database, and in many cases exceed the nominal pressure rating shown in the catalog. Users will be permitted to use pressures up to these actual allowed maximums. Allowed joint movements are also stored as part of the database and are printed with each proposed model. These values should be recorded for use in checking the model after a successful design pass has been completed. Pressure thrust is included in the modeling considerations for each of the expansion joint styles, removing this concern from the user. In the case of “tied” expansion joints, rigid elements are used to model the tie-bars. Restraints with connecting nodes are used to contain the pressure thrust, and to keep the ends of the expansion joint parallel. The Expansion Joint Modeling session is started by clicking the Expansion Joint button on the toolbar or selecting the MODEL - EXPANSION JOINT menu item from the pipe spreadsheet:

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Expansion Joint Modeler - From / To Nodes If the length of the current element exceeds the length of the expansion joint assembly, indicate whether the expansion joint assembly should be installed at the FROM end or the TO end of the current element.

Expansion Joint Modeler - Hinge/Pin Axis Enter the direction cosines which defines the axis of the hinge pin of the expansion joint assembly (i.e., the axis about which the joint can rotate). For example, if the hinge can rotate about the X-axis, enter: 1.0

0.0

0.0

Expansion Joint Modeler - Tie Bar Plane If an expansion joint has only two tie rods, permitting rotation about the plane defined by the tie rods, enter the direction cosines which, when crossed with the axis of the expansion joint assembly, defines the plane. In other words, enter the direction cosines corresponding to a line drawn from the mid-point of one tie rod to the mid point of the other.

Expansion Joint Modeler - Overall Length The length of a universal joint is variable, depending upon the length of the intermediate spool piece. Enter the desired length of the universal joint, or alternatively activate the check box in order to default to the shortest recommended length.

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Expansion Joint Modeler - Expansion Joint Database The current expansion joint vendor provides multiple databases.Select the one which you wish to use in the modeler. The default expansion joint vendor may be changed in CONFIGURE/SETUP (see "Expansion Joints" on page 28).

Expansion Joint Modeler - Modeler Results The proposed model of the expansion joint assembly is shown in the window at top. Click Build to insert this into the piping system model. The lower window shows the bellows stiffness parameters and allowable movements (from the vendor catalog). The allowable movements should be noted for later evaluation of the expansion joint.

Expansion Joint Modeler Notes Expansion joints cannot be inserted on an element that is either already a rigid or an expansion joint. Bends, however, can be at either end of the element where the expansion is being inserted. There does not have to be a length given on the element where the expansion joint is to be inserted. The six types of expansion joint models supported currently by CAESAR II are as listed below: Untied single bellows Tied single bellows Hinged single bellows Gimballed single bellows Untied universal bellows Tied universal bellows The four possible joint end types are Welded-end Slip-on flange Weld neck flange Plate flange If the length of the element to receive the expansion joint model is given, then the expansion joint assembly should fit within this length. If it does not, a warning message will be displayed to the user. If a universal joint has been requested, the length of the receiving element should be at least long enough to accept the smallest possible universal length, as defined by the minimum spool piece size from the manufacturers database. If the element to receive the universal expansion joint model is zero, the user will be prompted for the desired expansion joint length. If the element to receive the universal expansion joint model had an original length, then the maximum possible space available for the universal will be reported and the user asked for the length desired. If the element to receive any expansion joint is longer than the expansion joint to be inserted, the user will be prompted for the end of the element where the joint should be inserted, i.e. the From or To end. Overall universal lengths should be limited to about 10 times the pipe diameter before the center spool piece weight begins to become a problem. If there is a bend at either the From or the To end of the element to receive the expansion joint, then the length of the element must be defined.

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To find extra nodes needed for the expansion joint model, CAESAR II starts with the element From node and increments by one until a sufficient number of nodes not used elsewhere in the model are encountered. It is these nodes that are reported in the “proposed-model” pop-up window. Note that angular stiffnesses reported are given in the current set of units. Only the translational stiffness label is found at the top of the bellows stiffness report. If users are unsure about the rotational stiffness units, they may be seen either in the help screens or in the “UNITS” report from the LIST option. The user is prompted to adjust the stiffness for the expansion joint if the highest operating temperature is given and not equal to the expansion joint catalog design temperature. Note that this will in general produce bellows stiffnesses greater than those published in the catalog. Bellows, tie-bar, and hinge/gimbal assembly weights are combined together and distributed over the expansion joint rigid end pieces. The expansion joint modeler makes every attempt possible to generate nodes in the model that are unique. The user should inspect the nodes that are generated closely and make sure that he does not use them unintentionally in any future model building. There is a fair amount of computer logic set up to make intelligent decisions about the configuration that the user wants insofar as bends, hinges, tied bellows, and pressure thrust are concerned. Users should review generated CAESAR II models and be sure that everything is consistent with the user’s intentions.

Expansion Joint Design Notes It was common practice in the expansion joint industry to design expansion joint bellows and hardware (restraints) for the system pressure, and pressure thrust only. Generally, no consideration was given to the system deadweight or thermal forces. This poor practice has been tolerated in the past (prior to the widespread use of piping analysis programs) because of the following: The deadweight and thermal forces are normally small compared to the pressure and pressure thrust. Designers laid out expansion joints so that the thermal forces were very low and hence not significant. The allowable stresses used in hardware designs have a significant safety factor. The forces and moments generally were not known. Today when an expansion joint is modeled, it is recommended that ALL information relating to the joint be submitted to the expansion joint manufacturer. This is especially true of the forces and moments resulting from the operating loads, i.e. deadweight, thermal forces, and operating deflections. Better evaluations of the loading conditions on the bellows and hardware simply help the manufacturer make sure that his design is suited for the intended installation and service.

Torsional Spring Rates If the torsional spring rate is unknown, a large value should be entered (i.e. 1E10) to produce conservative results. These results will be conservative with respect to loads and non-conservative with respect to displacements. It is very common to rate the “bellows allowed torsion” by the amount of rotation experienced. Large torsional stiffnesses will result in small, seemingly satisfactory rotations. When results from a piping analysis are communicated back to the expansion joint manufacturer, it is important to report both the rotation AND the stiffness used to produce that rotation. A good estimate of bellows stiffnesses is given in Chapter 6 of the Technical Reference Manual.

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Bellows Application Notes The following considerations are important when selecting the number of convolutions for a particular application:

Movement Capability The more convolutions selected the greater the movement capacity of the bellows. It is a common practice to perform a quick hand calculation to estimate the required movement and then select the number of convolutions from the rated movements in the catalog. Once an analysis is performed, the exact evaluation of the bellows performance can be made using the expansion joint rating module program provided with CAESAR II.

Spring Forces The more convolutions selected, the lower the resulting bellows spring forces will be. This is particularly critical when the expansion joint is located near rotating equipment.

Available Space The more convolutions selected, the greater the required overall length. If working in a confined area, the number of convolutions may be restricted by the space.

Available Expansion Joint End-Types The following are expansion joint end-types available in the CAESAR II modeler.

Welded Standard pipe beveled for welding.

Slipon Slip-on flange.

WN Weld neck flange.

Plate Plate flange in accordance with the manufacturers catalog. Slip-on, weld neck, and plate flanges may not be available in all diameters and pressure ratings, i.e. over 24-in. diameters. Consult the catalog for specific interface dimensions, codes and materials. When the user selects a combination not available, he is warned that there is no database values for his particular geometry and line size.

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Pressure Rating The pressure rating should be equal to, or larger than the design pressure of the system. Note, however, that in many instances larger pressures can be tolerated than the rated pressure shown, in fact in many small diameter expansion joints the same bellows is used in 50, 150, and 300 psi-rated joints. The CAESAR II modeler contains the true minimum pressure limits for all of the bellows in the database, and checks the maximum pressure in the line (as entered by the user) against the allowed pressure (which as stated, is often greater than the rated pressure). This particular feature allows the user to select a smaller joint with more flexibility for certain applications.

Expansion Joint Styles Listed as follows are the six available styles of expansion joints that are built automatically by CAESAR II. With each type is a brief discussion of its use when associated with hot, pressurized equipment protection.

Untied Single unrestrained expansion joint. This type of joint can absorb movement in all directions. It will also subject the system to pressure thrust which must be designed for, external to the expansion joint !!! This type of joint should almost never be used by the expansion joint novice needing to protect hot, pressurized equipment. Guide restrictions limiting displacements into the joint, regular maintenance problems (because of all of the support hardware away from the bellows), and pressure thrust make using and analyzing this type of bellows difficult.

Tied Tied single expansion joint that is capable of transverse (lateral) movement only. Pressure thrust is restrained internally via the tie-bars. This is a good, dependable expansion joint to use because pressure thrust does not have to be designed for, tie rods provide stability to the overall joint (making working with it in the field easier), and there is a single displacement mode (i.e. lateral) that can be directly compared to the rated lateral movement in the catalog, without the need for the relatively complicated geometric calculations in the Expansion Joint Rating program. The drawbacks to the single TIED expansion joint are that they are fairly stiff in practice (often not providing the needed flexibility to sufficiently reduce the loads on sensitive equipment), and that the tie-bar assembly does provide some nonlinear restraining effect on flexibility that is unaccounted for in the analysis that may be appreciable when the bellows displacement becomes large (i.e. when it is most critical that it perform as predicted.)

Hinged Single hinged expansion joint. This type of joint can only angulate about one axis. Pressure thrust is retained internally by the hinge mechanism. Hinge joints are often used in pairs to absorb considerable displacement in a single plane, while transmitting very little load to any attached equipment. The piping system must, however, be designed to assure that displacement into the hinges is planar for all types of thermal and occasional loadings to be experienced by the system. Where pressure loads to be absorbed by the hinge mechanism are high, considerable friction forces can be generated that will somewhat limit further flexing of the joint, thus transmitting larger loads than expected back into the piping system.

Gimbal Single gimbal expansion joint. This type of joint can angulate about two axes. Gimballed joints restrain both pressure thrust and torsion via the gimbal mechanism. These joints are often used in pairs to absorb considerable displacement in several directions, while transmitting very little load to any attached equipment.

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U-UNIV Untied universal expansion joint. This type of unit is similar to a single unrestrained expansion joint. It can absorb movement in all directions and normally has a much higher capacity for transverse (lateral) deflection than a single bellows. An untied universal will subject the system to pressure thrust loads which must be designed for, external to the expansion joint. Even when pressure is negligible these joints can often be difficult to use in practice unless proper guiding of the thermal displacement protects the joint against undesired movement. Additionally, calculations for computing effective bellows axial movements for arbitrary movements in three dimensions is not trivial.

T-UNIV Tied universal expansion joint. Similar to a tied single joint, except that the tied universal has much higher transverse (lateral) movement capability. Pressure thrust loads are restrained internally via the tie-bars. These types of joints are a good option where vertical pipe runs close to the equipment are available. The tie-bars restrict movement to a single mode (lateral) and eliminate the worry about pressure thrust design. Longer lengths result in smaller lateral stiffnesses, but overall length is somewhat restricted by the weight of the center spool. A good rule of thumb is to restrict the overall length of the assembly to ten times the pipe diameter. Users should be careful not to put the assembly into compression, as the tie bar mechanisms are not designed to take this load and damage to the bellows can result. These six types of expansion joints are not all of the types available, but are the most common. If a joint is needed that is not covered by the above, it is suggested that the user select the style closest to that required, and then edit the resulting input once the EJ Modeler is complete and processing returns to the piping spreadsheet.

Materials Bellows can be formed from most ductile materials that can be welded by the automatic T.I.G. butt welding process and yield a homogeneous ductile weld structure. Due to the fact that the specific “media” content varies from system to system, and that most “media” data specified prior to system operation is approximate, with considerable fluctuation possible, it is not feasible to make specific recommendations concerning bellows materials. The following are the four most common bellows materials that are supported by CAESAR II: 304SS—A240 tp 304 Stainless Steel 316SS—A240 tp 316 Stainless Steel 600Inc—Inco 600 High Nickel 625Inc—Inco 625 High Nickel

Liners Internal liners smooth the flow through the expansion joint. The smooth flow reduces pressure drop and also prevents flow-induced vibration of the bellows. Liners are generally recommended when the flow velocity exceeds 1.3 ft./sec. as a minimum, and are definitely recommended when the flow velocity exceeds about 25 ft./sec. Consult the manufacturers catalog for additional information. Heavy gage liners should be used in high velocity or turbulent flow systems. Also heavy liners should be used when the media is abrasive.

Covers External covers are used to protect the very thin bellows, (0.010 to 0.090 in.) from mechanical damage. Covers are also recommended when the line is to be insulated.

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Title Page By pressing T at any time during pipe spreadsheet input, the current job's title page will be displayed (also may access through the MODEL - TITLE menu item). This is up to 60 lines of text that is stored with the problem, and may be used for detailing run histories, discussing assumptions, etc. These lines may be printed with the output report through the input echo.

Hanger Data System-wide hanger design criteria are activated from the input spreadsheet by choosing the Model Hanger Design Control Data.

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Spring hanger design can be globally controlled by entering data into the hanger control spreadsheet shown above. The Hanger Design Control Spreadsheet contains five items that also appear on each individual hanger design spreadsheet. These parameters can be set once in the run control spreadsheet, and will apply for all individual hangers to be defined unless specifically overridden at the individual hanger input level. These items are short-range springs rigid support displacement criteria maximum-allowed travel limit hanger table multiple load-case design option In addition, the Hanger Design Control spreadsheet tells the hanger design algorithm the number of temperature cases to be used in the hanger design, and whether or not the actual cold loads should be calculated. All of these options will be discussed in detail on the following pages. Whenever hanger locations are given for the first time, default parameters are assigned for all of the fields that show up in the Hanger Auxiliary Data field. These default parameters are taken from the Hanger Design Control spreadsheet. The user should, therefore, enter any non-default parameters that are to apply globally to all hangers in the Hanger Run Control Spreadsheet. An individual description of each Hanger Design Control Spreadsheet Data cell follows:

No. of Hanger - Design Operating Load Cases The number of load cases to be considered when designing spring hangers. This value may be between 1 and 9 and corresponds to the number of thermal load cases to be used in hanger design. If more than one Operating case is to be considered in the hanger design then the user must also select the Multiple Load Case Design option to be used.

Calculate Actual Cold Loads Enable this check box to cause CAESAR II to make one additional pass after the hanger design is completed and the hangers are installed, to determine the actual installed loads that should be used when the hangers are first installed and the load flanges adjusted in the field. This calculation tends to be important when the stiffness of the piping system is small, the stiffness of the hanger selected is high, and/or when the hanger travel is large (i.e. this usually is more important in smaller diameter piping systems that for some reason are spring supported away from equipment nozzles). Actual cold loads should definitely be calculated when springs in smaller diameter lines are to be adjusted in the cold position.

Allow Short Range Springs CAESAR II gives the user the option of excluding short range springs from consideration from the selection algorithms. In some instances short range springs are considered specialty items and are not used unless their shorter length is required for clearance reasons. In this case, this check box should be cleared by the user. If this option is not activated, CAESAR II will select a mid-range spring over a short-range spring, assuming they are more standard, readily available, and in general cheaper than their short-range counterparts. If the default should be that short range springs are used wherever possible, then check the box on the Hanger Design Control Spreadsheet.

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Allowable Load Variation (%) This is the user specified limit on the allowed variation between the hot and cold hanger loads. If not specified, the only limit on load variation is that inherent in the spring table. This is approximately 100% when the hot load is smaller than the cold load, and 50% when the hot load is larger than the cold load. Hot loads are smaller than cold loads whenever the operating displacement in the Y direction is positive. The default value for the load variation is 25%. The user is advised to enter this value in the Hanger Run Control Spreadsheet before any hangers are defined. Bergen-Paterson is the only manufacturer that specifically gives 25% as a design limit. The Allowable Load Variation is the percentage variation from the hot load:

Variation =

(Cold Load) - (Hot Load) Hot Load

or as may be more familiar: Variation =

(Travel)(Spring Rate) Hot Load

The Allowable Variation is entered as a percentage, i.e. twenty five percent would be entered 25.0. The Allowable Load Variation can have different values for different hanger locations if necessary by entering the chosen value on the individual hanger spreadsheets or it can be entered on the Hanger Design Control Spreadsheet to apply to all hangers in the model.

Rigid Support Displacement Criteria This is a parameter used to determine if there is sufficient travel to design a spring. The Rigid Support Displacement Criteria is a cost saving feature that replaces springs that are not needed with rigid rods. The hanger design algorithm operates by first running a restrained weight case. From this case the load to be supported by the hanger in the operating condition is determined. Once the hanger design load is known, an operating case is run with the hot hanger load installed to determine the travel at the hanger location. If this determined hanger travel is less than the Rigid Support Displacement Criteria then a rigid Y support is selected for the location instead of a spring. If the Rigid Support Displacement is left blank or zero, the criteria will not be applied. The Rigid Support Displacement Criteria may be specified on the Hanger Run Control Spreadsheet, or on each individual hanger spreadsheet. The value specified on the Run Control Spreadsheet is used as the default for all hangers not having it defined explicitly. A typical value to be used is 0.1 in. Important: In some cases a Single directional restraint should be inserted instead of a rigid rod. Rigid rods are double acting restraints which can in some cases develop large “hold down” forces that don’t really exist because the support has lifted off, or because the rigid rod has bowed slightly. When this condition develops the user should rerun the hanger design inserting single directional restraints where rigid rods were put in by CAESAR II.

Hangers should probably never be replaced by rigid rods in very stiff parts of the piping system that are usually associated with rotating equipment or vessel nozzles that need to be protected.

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Maximum Allowed Travel Limit To specify a limit on the amount of travel a variable support hanger may undergo, specify the limit in this field. The specification of a maximum travel limit will cause CAESAR II to select a constant effort support if the design operating travel exceeds this limit, even though a variable support from the manufacturer table would have been satisfactory in every other respect. Constant effort hangers can be designed by inputting a very small number for the Maximum Allowed Travel Limit. A value of 0.001 is typical to force CAESAR II to select a for a particular location.

Hanger Table The following spring tables are currently included in CAESAR II: 1. Grinnell

2. Bergen Power

3. Power Piping

4. NPS Industries

5. Lisega

6. Fronek

7. Piping Technology

8. Capitol

9. Piping Services

10. Basic Engineers

11. Inoflex

12. E. Myatt

13. SINOPEC

14. BHEL

15. Flexider

16. Carpenter & Paterson

17. Comet

18. Hydra

19. Sarathi

20. Myricks

21. China Power

22. Pipe Supports USA

23. Quality Pipe Supports

Additional design options are invoked by further modifying the hanger table number: Add + 100 to get Extended Range Add + 200 to get Cold Load Design Add + 400 to get the Hot load centered if possible. For example, to use Grinnell Springs and cold load design the user would enter: 1 + 200 = 201.

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To use Grinnell “Extended Range” springs, Cold Load Design, and to get the Design Hot load centered in the middle of the hanger table, if possible, the user would enter: 1 + 100 + 200 + 400 = 701. A single job can use any combination of tables. The hanger table can be specified on the individual hanger spreadsheet, or can be specified on the Hanger Run Control Spreadsheet (see "Hanger Data" on page 103). If a spring table is entered in the Hanger Design Control Spreadsheet then it is used as the default for all subsequent hangers defined. The Hanger Design Control Spreadsheet defaults to the hanger tablespecified in the configuration file. The maximum load range was included in CAESAR II to permit the selection of less expensive variable support hangers in place of constant effort supports when the spring loads are just outside the manufacturers recommended range. Users should make sure that the maximum load range is available from the manufacturer as a standard item. Cold Load Spring Hanger Design. Cold Load Spring Hanger Design is a method of designing the springs, whereby the hot (or operating) load is supported in the cold (or installed) position of the piping. This method of spring design offers several advantages over the more usual hot load design: Hanger stops are easier to remove. There is no excessive movement from the neutral position when the system is cold or when the stops are removed. Spring loads can be adjusted before the system is brought up to temperature. Some feel that the cold load approach yields a much more dependable design. In some system configurations, operating loads on connected equipment are lower. A typical configuration resulting in this “load-reduction” is one where a hot vertical riser, anchored at the bottom, turns horizontally into a nozzle connection. The spring to be designed is at the elbow adjacent to the nozzle. Operating loads are lower because the difference between the hot and cold loads counters the moment produced by the vertical thermal expansion from the anchor. The disadvantages to cold load design are In some systems, in the hot condition the loads on rotating equipment may be increased by a value proportional to the spring rate times the travel. Most installations are done on a hot load design basis. The decision to use hot or cold load hanger design rests with the user. Middle of the Table Hanger Design. Many designers prefer that the hot load be centered as close as possible to the middle of the spring table. This is to provide as much “variability” either way before the spring bottoms out when the system is hot. This was a much more needed feature, before effective computer modelling of piping systems, when the weights at hangers were approximated by chart methods or calculated by hand. Activating this option does not guarantee that spring hot loads will be at the middle of the spring table, but CAESAR II makes every effort to move the hot load to this position. The CAESAR II design algorithm will go to a higher size spring if the design load is closer to the middle of the larger springs range, but will never switch spring types. This option can only result in a one size larger spring when it is effective. CAESAR II will attempt to move the hot load to the next higher spring when it is within 10% of the maximum travel range for the spring. If the new spring is not satisfactory then the old one will be used, even though its hot load is within 10% of the high end of the table load range, to get a springs hot load close to the middle of the table.

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Extended Load Range Springs. Extended load ranges are the most extreme ranges on the spring load table. Some manufacturers build double spring supports to accommodate this range, and others adjust the top or bottom travel limits to accommodate either end of the extended table. Before using the maximum ranges, the user should make sure that the manufacturer can properly supply the spring. Use of the extended range often eliminates the need to go to a constant effort support. Lisega springs do not support the "extended range" idea. A request for extended Lisega springs results in the standard Lisega spring table and ranges.

Multiple Load Case Design Options Whenever more than one thermal load case is to be used in the hanger sizing algorithm, CAESAR II must know how the user wishes to weigh the results from the different cases. There are currently 13 different methods that may be used for multiple load case hanger design selection. These 13 methods are listed as follows and are described in greater detail under the hanger auxiliary data section.

1

Design per Load Case #1

2

Design per Load Case #2

3

Design per Load Case #3

4

Design per Load Case #4

5

Design per Load Case #5

6

Design per Load Case #6

7

Design per Load Case #7

8

Design per Load Case #8

9

Design per Load Case #9

10 Design for the maximum operating load 11 Design for the maximum travel 12 Design for the average load and the average travel 13 Design for the maximum load and the maximum travel

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Special Execution Parameters The Special Execution Parameters dialog is invoked by choosing the KAUX - SPECIAL EXECUTION PARAMETERS option from the menu or by clicking it's toolbar from the piping spreadsheet. The Special Execution Parameters, once chosen, remain set for that particular job.

Print Forces on Rigids and Expansion Joints Forces and moments are not normally printed for rigid elements and expansion joints, because the forces that act on these elements can usually be read directly from the forces that act on the adjacent pipe elements. Check this box to cause forces and moments to be calculated and printed for all rigid elements and expansion joints in the system. If there are a considerable number of rigid elements in the job, this option will cause some slowdown in the output processor, and will cause the solution intermediate files to increase slightly in size.

Print Alphas and Pipe Properties If the user checks this box he will be given the option, at the error checking level, to print the interpolated expansion coefficients along with the pipe, insulation, and fluid weights. This report can be very useful during error checking to help identify possible problems in the temperature or weight input specifications. Rigid elements and expansion joints are treated just like straight pipe. Rigid weights and insulation factors are not reflected in this table.

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Activate Bourdon Effects Choose the option from the drop list to activate the Bourdon pressure effect. The Bourdon pressure effect causes straight pipes to elongate, or displace along their axes, and causes curved pipes, or bends to elongate along the line that connects the bends “near” and “far” nodes. If the Bourdon effect is not activated there will be no global displacements due to pressure. The Bourdon effect is always considered when plastic pipe is used, regardless of the setting of the Activate Bourdon Effects flag. By default CAESAR II does not include the Bourdon effect in the analysis of steel piping systems, i.e. there will be no displacements of the system due to pressure. As an option, the user may include pressure displacement effects if he wishes. These effects can be appreciable in long runs of pipe, or in high pressure, large diameter bends adjacent to sensitive equipment. Bourdon effects are almost always important in fiberglass reinforced plastic piping systems. For this reason the Bourdon (Translational) is automatically turned on for all FRP pipe runs and bends. Two Bourdon options are available: Translational pressure deformations only. Translational and rotational deformations. The Translational option should be used when the elbows in the system are forged or welded fittings and can reasonably be assumed to have a circular cross section. The Translational and Rotational option should be used when the bends in the system are fabricated by the hot or cold bending of straight pipe. In these cases the slight residual ovalization of the bend cross section, after “bending,” will cause the bend to try to “straighten out” when pressurized. Fixed end moments are associated with this “opening” that do not exist when the original shape of the bend crosssection is circular.

Branch Error and Coordinate Prompts This is a dual purpose flag activated by selecting the appropriate option from the drop list. The user is prompted for two pieces of information by this input: The loop closure tolerance. The global coordinates of the first point of the piping system and each following piece of the piping system that is not connected to the first. This data is needed the first time CAESAR II prepares a global geometry calculation. This calculation is made on three different occasions: Before preprocessor plots are generated Before global coordinate reports are built Before error checking is performed Alternatively, prompting may be avoided by entering the global coordinates by using the Edit - Global (see "Global Coordinates" on page 85) command from the main spreadsheet. There are several major uses for this flag: To set the loop closure tolerance To properly define the elevation of the piping system for wind/wave load calculations To give the proper east-west/north-south coordinates for dimension checks

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To move parts of the system around in the plotted output for visual checking Whenever the user creates a physical “loop” in the piping system there will be at least two different sets of dimensions between the same points. If the two dimensions are not within a certain tolerance of each other, a fatal error will occur. This tolerance may be set interactively or in the configuration file. Selecting "Both" for the Branch Error and Coordinate Prompts directive causes CAESAR II to interactively prompt for this tolerance.

Thermal Bowing Delta Temperature This field is used to specify the temperature differential which exists between the top of the pipe and the bottom of the pipe. This differential is used to compute an elemental load, added to each temperature case for “horizontal” pipes. This entry should be computed from the equation: dT = Ttop - Tbottom For example, consider a horizontal pipe where the temperature on the top is 20 degrees hotter than the temperature on the bottom. The proper value to enter in this field will be 20, not -20.

Liberal Stress Allowable A conservative formulation of the allowable expansion stress range for many codes in CAESAR II is calculated from: f ( 1.25 Sc + .25 Sh ) When the user requests that the “Liberal Allowable” be used, the difference between Sh and Sl, provided Sh > Sl, will be added to the term inside the parenthesis, i.e. SA(Liberal) = f[ 1.25 Sc + .25 Sh + ( Sh - Sl) ] The liberal expression will only be employed when there is at least one sustained stress case in the load set. If there is more than one sustained stress case in a single problem, then the largest of Sl, considering all of the sustained cases, for any single element end will be chosen to subtract from Sh. Because the sustained stress varies from one pipe to another, the allowable expansion stress will also vary. By default, CAESAR II uses the liberal stress allowable setting in the configuration file, (see "Liberal Expansion Stress Allowable" on page 14) in its computation of the expansion stress allowable. (New models are created using this configuration setting.) Users not wishing to utilize this default setting for calculating the expansion can simply change the state of this check box.

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Uniform Load in G's Uniform loads can be defined in either terms of force per unit length or in terms of a magnifier times gravitational loading (g). The loading magnifier can act in any direction and is specified by giving its components along the three orthogonal X, Y, and Z axes. Gravitational loading is used most often to model the static equivalent of a dynamic earthquake loading. When activated, the uniform load fields on the pipe spreadsheet change from UX, UY, and UZ to GX, GY, and GZ. An entry of: GX = 1.0, GY = 0.0, GZ = 0.0 represents a lg loading on the piping system in the horizontal X direction. An entry of: GX = 0.0, GY = -1.0, GZ = 0.0 represents a 1.0g load in the minus Y direction, and is exactly equal to the pipe weight load. Gravitational load entries are distributive properties similar to the uniform loads they replace. Once specified, the given g loading will act on all subsequent pipe elements until changed or zeroed. The user may activate the gravitational load option at any time during the input of the problem. The gravitational load option is activated by checking the box. Note: Earthquake loads are occasional loadings and as such are not directly addressed by the CAESAR II recommended load case logic. Users must form their own combination cases at the output processor level that represent the algebraic sum of the stresses due to sustained and occasional loads. See Chapter 6 of the Technical Reference Manual for more on Occasional Load Case definition.

Stress Stiffening Due to Pressure (all codes except IGE/TD/12) This directive activates the Pressure Stiffening effects in straight pipes. CAESAR II applies the stress stiffening matrix to the elemental stiffness matrices (of straight pipes only) using an axial force P equal to the internal pressure as selected from the drop list times the internal area of the pipe. Note that other internal forces (due to thermal or imposed mechanical loads) are not included in the P force as this is not a non-linear effect. Note that Stress Stiffening is not currently available for pressure cases 3 through 9.

Base Stress/Flexibility on (IGE/TD/12 code only) This directive indicates whether to base the IGE/TD/12 stress analysis (element stiffness and section modulus) on the nominal wall thickness, maximum wall thickness (nominal wall thickness (nominal plus mill tolerance), or minimum wall thickness (nominal minus mill tolerance). Note that corrosion is deducted from the section modulus for all stress types except Hydrotest, and that regardless of this selection, Stress Concentration Factors are always based upon nominal dimensions.

Ambient Temperature The default ambient temperature for all elements in the system is 70°F/21°C. If this does not accurately represent the installed, or zero expansion strain state, then enter the actual value in this field. The ambient temperature is used in conjunction with the specified hot temperature and the interpolated expansion coefficient to calculate the thermal expansion per inch of pipe length experienced by the element when going from the ambient temperature to the hot temperature. A default ambient temperature can be defined in the configuration file (see "Ambient Temperature" on page 4). This (configuration) value is used when a new model is created to set the value of ambient temperature.

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FRP Coefficient of Thermal Expansion (x 1,000,000 ) The default thermal expansion coefficient for fiberglass reinforced plastic pipe is 12.0E-6 in./in./deg.F. If the user has a more suitable value for the particular composite then that value should be inserted in this field. For example, if the improved value was: 8.5E-6 in./in./deg.F., then the user would enter 8.5 in this field. The exponent (E-6) is implied. This expansion coefficient is used in conjunction with the temperatures entered on the pipe spreadsheet for each plastic pipe element to calculate the thermal expansion for the element. It should be noted that this method does not provide for any variation in the thermal expansion coefficient as a function of temperature. This could prove limiting should there be parts of the system at different non-ambient temperatures. In this case the user may always calculate the thermal expansion at temperature in inches per inch and input this value directly into the Temperature field on the pipe spreadsheet. For new models, the default value is obtained from the configuration file.

FRP Ratio of Shear Modulus/Emod Axial In this field, the ratio of the shear modulus to the modulus of elasticity (in the axial direction) of the fiberglass reinforced plastic pipe used should be entered. For example, if the material modulus of elasticity (axial) is 3.2E6 psi, and the shear modulus is 8.0E5 psi, the ratio of these two, 0.25, should be entered here. For new models, the default value is obtained from the configuration file.

FRP Laminate Type The default Laminate Type (as defined in the BS 7159 code) of the fiberglass reinforced plastic pipe used should be entered. Valid laminatetypes are Chopped strand mat (CSM) and woven roving (WR) construction with internal and external surface tissue reinforced layer. Chopped strand mat (CSM) and multi-filament roving construction with internal and external surface tissue reinforced layer. All chopped strand mat (CSM) construction with internal and external surface tissue reinforced layer. This entry is used in order to calculate the flexibility and stress intensity factors of bends; therefore this default entry may be overridden using the Type field on the bend auxiliary spreadsheets.

Z-Axis Vertical Traditionally CAESAR II has always used a coordinate system where the Y-axis coincides with the vertical axis. In one alternative coordinate system, the Z-axis represents the vertical axis (with the X axis chosen arbitrarily, and the Y-axis being defined according to the right hand rule. CAESAR II now gives the user the ability to model using either coordinate system, as well as to switch between both systems on the fly in most cases.

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CAESAR II Technical Reference Manual Defaulting to Z-Axis Vertical The user’s preferred axis orientation may be set using the Tools-Configure/Setup option, on the Geometry Directives (see "Z-Axis Vertical" on page 19) tab, as shown in the figure below. Clicking the Z-Axis Vertical check box causes CAESAR II to default any new piping, structural steel, WRC 107, NEMA SM 23, API 610, API 617, or API 661 models to use the Z-axis vertical orientation. Old models will appear in the orientation in which they were last saved. The default value in Configure/Setup is unchecked or Y-axis vertical.

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Orienting a Piping Model to Z-Axis Vertical A new piping model will determine its axis orientation based on the setting in the Configure/Setup module, while an existing piping model will use the same axis orientation under which it was last saved. The axis orientation may be toggled from Y-Axis to Z-Axis vertical by clicking the check box on the Kaux-Special Execution Parameters screen, as show in the figure below.

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Clicking this check box causes the model to immediately convert to match the new axis orientation (i.e., Y-values become Z-values) or vice versa, so there is no change in the model only in its representation, as shown in the following figures:

This allows any piping input file to be immediately translated from one coordinate system into the other. When including other piping files in a model, the axis orientation of the included files need not match that of the piping model. Translation occurs immediately upon inclusion. When including structural files in a piping model, the axis orientation of the include files need not match that of the piping model. Translation occurs immediately upon inclusion. The axis orientation on the Static Load Case Builder (i.e., wind and wave loads), the Static Output Processor, The Dynamic Input Module, and the Dynamic Output Processor is dictated by the orientation of the model’s input file. Orienting a Structural Model to Z-Axis Vertical. A new structural model will determine its axis orientation based on the setting in the Configure/Setup module, while an existing structural model will use the same axis orientation under which it was last saved. The axis orientation may be toggled from Y-Axis to Z-Axis Vertical by changing the value of the Vertical Command, activated by clicking the button on the toolbar, or through the COMMANDS/MISCELLANEOUS/VERTICAL menu command as shown in the figure on the next page.

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Note: Unlike the piping and equipment files elsewhere in CAESAR II, toggling this setting does not translate the structural input file, but rather physically rotates the model into the new coordinate system, as shown in the figures below. When including structural files in a piping model, the axis orientation of the included files need not match that of the piping model. Translation occurs immediately upon inclusion. When analyzing a structural model on its own, the axis orientation of the Static Load Case Builder (i.e., wind and wave loads), the Static Output Processor, the Dynamic Input Module, and the Dynamic Output Processor is dictated by the orientation of the structural model’s input file. Orienting an Equipment Model to Z-Axis Vertical. The WRC 107, NEMA SM 23, API 610, API 617, and API 661 equipment analytical modules may also utilize the Z-axis vertical orientation. A new equipment model will also determine its axis orientation based on the setting in the Configure/Setup module, while an existing equipment model will use the same axis orientation under which it was last saved. The axis orientation may be toggled from Y-Axis to Z-Axis Vertical by clicking the check box typically found on the second data input tab of each module. Clicking this check box causes the model to immediately convert to match the new axis orientation (i.e., Y-values become Z-values) or vice versa, so there is no change in the model only in its representation, as shown in the following figures: When using the Get Loads From Output File button to read in piping loads from CAESAR II output files, the axis orientation of the piping files need not match that of the equipment model. Translation occurs immediately during the read-in of the loads.

Bandwidth Optimizer Options The bandwidth optimizer is used to order the set of equations that represent the piping system for both static and dynamic analyses. The optimizer may be run with a variety of different switch settings. The default settings were chosen for their combination of ordering efficiency and speed. These settings should suffice for the majority of piping systems analyzed. For systems having greater than 100 nodes, or that are highly interconnected, the following optimum parameters should be used. Optimizer Method Both Next Node Selection Decreasing Final Ordering Reversed Collins Ordering Band Degree Determination Connections User Control None If the User Control is set to "Allow User Re-looping," CAESAR II will let the user interactively try as many different combinations of switch settings as desired. When the most efficient ordering is obtained, the user may continue on with the analysis. This interactive prompting for optimization parameters is done in the analysis level processing.

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Combining Independent Piping Systems Input from other jobs may be “included” into the current piping model. Piping models added may have a node offset applied and can optionally be rotated about the Y axis before being added. Choose KAUX/INCLUDE PIPING INPUT FILES from the Pipe Input spreadsheet to "include" other input files. When including other piping models, the user is asked for the following:

File Name. The user may browse for the file name. The file need not reside in the current data directory. Read Now (Y/N/L) Y, if the file is to be read immediately and stored as part of the current input (the file read may be edited as part of the current job). N, if the file is to be read for plotting and fully processed only during error checking (the file read may not be edited as part of the current job). The L option is discussed under "Large Job Includes," below. Rotation. If not zero, then gives the angle about the Y axis by which to rotate the model before including it in the current job. The rotation applies regardless of the (Y/N) setting. Note: Restraints, uniform loads, and concentrated forces are NOT rotated. Additionally, the rotation of the model can be accomplished from the LIST Utility. Node Increment. The increment to be added to all of the nodes in the model before including it in the current job. The node increment applies regardless of the (Y/N) setting.

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Including Structural Models Include Structural Input Files. This input screen is used to include an already-built structural model into the current job. The structural model must have been built and successfully error checked in the structural steel preprocessor accessed from the CAESAR II MAIN MENU. Once a structural model has been built, it may be included into any piping input using the above screen. The names of up to 20 different structural models to be included are entered into the data area available. Once this is done, the structural model may be plotted and analyzed with the piping model. The structural models need not reside in the current directory. Piping systems are usually tied to structural steel models by the use of restraints with connecting nodes. The user should make absolutely sure there are no node number conflicts between structure and pipe models. Once a restraint with a connecting node is defined between the pipe and structure, CAESAR II knows where to put the structure in the resulting preprocessor plot. If no connection between the pipe and the structure is given, the structure will be plotted starting from the origin of the piping system (and the resulting plot will most likely “look funny”).

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List/ Edit Facility The CAESAR II input listings allow the display of all applicable input data in a context display. This mode is accessed through the Edit - List command. optionally in a user specified format. The user can edit, delete or modify data in the lists. The List option screen contains a row of tabs at the bottom that are used to select the various list options to be displayed. When a tab has been selected the row headings at the top of the spreadsheet will reflect the specific input data and controlling parameters displayed in the corresponding columns. All of the input data can be accessed through the various list reports. An example list control screen is shown below.

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The reports are generated in column format in a window like that shown above that the user can interactively review or modify. The cursor can be moved into any field and a new value entered to replace the original value. The reports may be scrolled vertically or horizontally. Help may be requested by pressing the key while in any of the data cells. Cell input may be deleted by highlighting the selection and pressing the key. The list spreadsheet supports standard windows commands such as Cut and Paste on a field-by-field basis. The User may edit input data on the list spreadsheet, which will then update the input spreadsheets as well. Values that carry forward on the input spreadsheet are highlighted in red where there is a change in the data value. For example, in the sample spreadsheet shown, the diameter changes from 219.075 mm to 508.0 mm on the element from node 90 to 100 so the new diameter is highlighted in red. Other options from the Element List include the following: The Find command (invoked with F or EDIT - FIND menu item) is used to quickly jump to the element where the given node is located. Find remembers the last node number entered, so subsequent “finds” of the same node can be accomplished by typing F. Access to the element Auxiliary Data screens is available by highlighting an element row and choosing the Aux button from the toolbar or alternatively by right-clicking on an element line and picking the BLOCK OPERATIONS-AUX item in the popup menu. By single-clicking on any checked items from the window shown below the appropriate Auxiliary Data field will be displayed. The user may edit the data in the Auxiliary Data field, which will in turn update the input spreadsheet. Additionally, the user may enter new data by double-clicking on any of the unchecked boxes to bring up that item's Auxiliary Data screen. An entire Auxiliary Data field may be deleted by double-clicking on the checked item (a prompt will warn the user of the impending delete operation).

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Block Operations The list editor has the ability to perform global editing operations on selected parts of the piping system. These operations include varieties of rotations, duplications, node renumbering, and status reporting. Block operations are available on the element list only. Move the cursor to the first element in the group to be operated on and click the row number for that item. This element should become highlighted. Move the cursor to the last element in the group to be operated on and click on the corresponding row number while holding the <shift> key down. The entire group of elements will be highlighted. This “highlighting” defines the elements that any block operations will change. A block may contain any number of elements from a single element to every element in the model. A block must be defined before CAESAR II will allow the user to enter the BLOCK OPERATIONS menu item. After the block has been identified select Block and one of the following sub-menu items to perform the indicated operation (or right-click in the list processor and select one of the following from the pop-up menu):

Rotate The Rotate dialog box is shown in the following figure. The user may rotate the block through some angle about the X, Y or Z axis. The Unskew option helps the user take a skewed geometry and return it to an orthogonal orientation. The Setup option permits the user to determine what in the block should be rotated, including restraints, displacements, force/moments, uniform loads, and flexible nozzles. The default is for all of these items that appear in the block to be rotated with the block. Data/message screens illustrating an example rotation are shown as follows.

Delete This command deletes the selected block.

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Duplicate The Duplicate dialog is shown in the figure below. The user can make identical copies of the block or can make mirror image by "flipping" the chosen elements in one of the orthogonal planes. Mirror imaging is done on the piping delta dimensions only (i.e. restraints are copied, but not mirror imaged, i.e.: a +Y restraint will not become a -Y restraint when mirrored in the XZ plane.)

The duplicate “setup” option works just like the rotation setup option. Restraints, displacements, forces/moments, uniform loads and nozzles may individually be included or excluded from the duplication. Once the type of duplication is determined the user must decide the following: Where in the input to put the duplicated group of elements. Either at the end of the current block, the end of the input file, or after a specific element in the model. What node increment to add to the nodes in the block so that they define unique pipe elements. Be sure this increment is large enough to avoid any duplication of node numbers.

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Nodes On certain occasions the node numbering in a particular area of the model may not be to the user's liking. To renumber a part of the model in a more logical fashion use the Block-Node menu command. The two available options are Increment and Renumber as shown in the following figure.

The user enters the starting node and the increment for the block's nodal renumbering. Every node in the block on the piping system will be renumbered. The user must be sure that the starting node and increment will result in unique node numbers for the elements being renumbered. This feature can be used to clean up part, or all of the piping system. It is not unusual for an analyst to put the entire model in one block and do a full renumber on all of the nodes. This often presents a much cleaner picture of the analysis to the client. Users are urged to make copies of any large jobs before renumbering them. Users should be particularly careful when renumbering systems containing large numbers of interconnected restraints with Cnodes. Note: It is common for CAESAR II not to renumber a Cnode in a block having perceived that the Cnode is connected to a node outside the block. (In fact Cnode will not be renumbered if they do not connect to a node in the block and on the piping system.) Any possible confusion can be avoided in these instances by starting the renumbering at a node greater than the largest node in the model. If all of the nodes are renumbered successfully (i.e. there aren't any dangling Cnodes), then the node Increment command can be issued with a negative increment to shift the newly renumbered nodes back into the original range.

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Printing an Input Listing An input listing can be printed by using the File - Print command from the spreadsheet. The program prompts the user to select the reports to print, prior to printing. The user can change the report contents through modification of a .inp file. Any time an input listing is written to a file or to the printer, the format of each of the reports is obtained from a .inp file. The .inp files are ASCII text files which can be modified to create reports of differing styles or content. The file Initial.inp can be modified to change the page length in the report, and the starting and stopping column positions. Any text editor (such as Notepad) can be used to change any of the .inp files. Users changing .inp files may receive fatal errors during report generation if impossible formats, or invalid commands are requested. Note: For users preferring a different (more columnar) form of the basic element data, three additional formatting files have been provided. ELEMENT0.INP -

COADE standard element format

ELEMENT1.INP -

1st alternate element format

ELEMENT2.INP -

2nd alternate element format

ELEMENT3.INP -

3rd alternate element format

To utilize any of these formatting files, change directories to the CAESAR II\System directory. Then, copy the desired formatting file into Element.inp. To print an Input Echo from the input spreadsheets, choose FILE - PRINT from the pull-down menu. To write an Input Echo to the screen for review, choose FILE - PRINT PREVIEW from the pull-down menu. Note:

An input listing may also be printed from the output module, as part of the entire output report.

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Input Plotting The following figure shows the CAESAR II graphics interface.

There are several methods of accomplishing nearly every command in the Input Plot Utility. Commands may be enabled by clicking toolbar buttons, selecting drop-down menu items, or through the use of hot keys.

Model Rotation, Panning, and Zooming In general it is faster to use the hot keys for model rotation and the mouse button for model translation. It is much faster to turn volume plot off prior to model rotation and translation with hot keys. CAESAR II toggles the volume off when using the mouse to pan the model and restores the volume at the conclusion of the pan. The shift key may be used to toggle between Rotation and Panning functionality of the arrow keys. The letters SHFT appear at the bottom right of the Plot Window when the Shift option is enabled. Note that the Shift key need not be held down to enable the SHFT option.

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SHFT Option Disabled Rotations: About the Y-axis, use the right and left arrow keys. About the Z-axis, use the insert and delete keys. About the In-Plane axis (parallel to the display), use the up and down arrow keys. About the X-axis, press the key to view from the Z-axis or the key to view from the Y-axis, then use the up and down arrow keys.

SHFT Option Disabled Panning: Pan up with the <Page Up> key Pan down with the <Page Down> key Pan left with the key Pan right with the <End> key

SHFT Option Enabled Panning: To Pan Left and Right, use the left and right arrow keys. To Pan Up and Down, use the up and down arrow keys. Note: Other key combinations are possible, and the user is urged to experiment with different keystrokes to find the optimum combination for themselves. Toolbar buttons may also be used for Rotations and Translations and the volume plot should be disabled first. This method is generally slower than hot keys or the mouse. A particularly effective method for quickly panning the plot is to right-click the mouse on the Plot window and choose Pan from the pop-up menu. Then the model will move with the mouse about the window. To disable this directive, either press the <Esc> key or right-click the mouse and choose PAN again.

Zooming Zooming is accomplished with either the + or - keys or by simply left-clicking the mouse and dragging it to draw a box around the portion of the model to be enlarged. Another effective method of zooming is accomplished by right-clicking on the Plot window and choosing Zoom from the pop-up menu, then dragging the mouse up and down to zoom in and out. When satisfied with the view, either press the <esc> key or right-click the mouse and choose ZOOM again from the pop-up menu to deactivate mouse controlled zooming.

Reset Plot Reset Plot may be chosen from either the Toolbar, from the menu by selecting VIEW/RESET or by pressing the function key. This returns the plot to the original default position as when the Plot window is first entered from the Input Spreadsheet.

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Views The Input Plot may be viewed Isometrically (default), or along any of the three global axes. To view the plot in the two-dimensional plane normal to a given axis, either press the axis letter on the keyboard (X, Y, or Z), choose the corresponding Toolbar button, or pick the appropriate menu item under the View menu. To display the plot in all four views simultaneously, choose the 4 views button, press 4, or select the 4 VIEWS menu item under the View menu. To return to the SE Isometric view, choose the SE ISO View button, the function key, or select SOUTHEAST ISO VIEW from the View drop-down menu.

Volume Plotting The three different volume plots available in CAESAR II are the Volume Plot, the Wire Frame Plot, and Rendering. Rendering views the model as a 3-D solid, while Volume Plot is the volume outline view. Toggle Volume on and off with the key, the Volume button on the Toolbar, or the VOLUME PLOT menu item from the View menu. Toggle 3-D Rendering or 3-D Wire Frame on and off with either the appropriate button on the Toolbar or the menu choice under the View menu.

Displaying Element Information Model information may be displayed on the plot by choosing the appropriate Toolbar button, the dropdown menu item under the Options menu, or the appropriate Hot Key (as shown on the dropdown menu). The following is a short description of the available model information on the Plot window:

Expansion Joints and Rigids Plotted by default and displayed in green on the Plot window.

Restraints Also plotted in green, translational restraints are plotted as isocoles triangles with the apex touching the pipe in the direction of free travel (ex: a +Y restraint looks like a triangle with it's base below the pipe). Flexible restraints are drawn with small spring symbols. “Gapped” restraints are drawn slightly removed from the centerline of the pipe. Rotational restraints are plotted twice as wide at the base of the arrow-head as translational restraints. The user is encouraged to experiment to determine all the symbols that CAESAR II uses to depict various restraint types.

Anchors Anchors are shown as green triangles with standard anchor lines protruding from the base.

Hangers Drawn as brown (default) cylinders with a line extending to the hanger node.

Nozzles Brown Cylinder with larger "cap" at vessel connection point.

Bends, Tees All shown as highlighted straight lines connecting the associated boundary nodes.

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Forces, Moments, Displacements The node is highlighted and the vectors are displayed numerically.

Thicknesses, Diameter, Length, Material Number Element pipe wall thicknesses, insulation thicknesses, material number, element diameter and length are displayed numerically near the midpoint of the element.

Node Numbers Node Numbers are displayed in yellow. Only From and To nodes are displayed.

Range The Range command may be used to plot only those elements that contain nodes within the range specified by the user. This is particularly helpful when attempting to locate a specific node in a rather large model.

Highlight The Highlight option is used to mark elements having similar properties. Each subsequent highlight is cumulative. Very descriptive color displays can be generated and interactively rotated to give the user a clear description of the conditions used for highlighting.

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Piping Input Graphics The piping preprocessor also provides interactive graphics and listing functions to facilitate model editing and verification. Model verification can be performed using either the Graphics or List utilities, although a combination of both modes is recommended. When drawing the model, the status bar displays “drawing node X of Y” and changes to “Ready” when finished. The model remains functional while drawing.

Hoops Plot Tools (toolbar): Reset Plot

Displays the plot in its default configuration: removes any highlighting, sets ISO view, renders mode, and zooms to extent. This action may also be activated by clicking the F9 function key on the keyboard. Disregards or repeats the user’s last action.

Undo/Redo The view can be zoomed in by dragging a box around the desired area. Zoom to Window The model will zoom in or out to fit entirely on the screen. Zoom to Extents Front/Back; Top/Bottom;

Allows selecting among predefined generally used views. Pressing X, Y, or Z buttons on the keyboard will set the model in “right”, “top”, or “front” views correspondingly. Additionally, holding down the SHIFT button while pressing X, Y, or Z keys will show “left”, “bottom”, or “back” views respectively.

Left/Right

ISO View

View in Southeast isometric mode. This action may also be activated by clicking the F10 function key on the keyboard. Activates an interactive rotation feature when the left mouse button is clicked.

Orbit

Zoom

The model may be zoomed in/out by moving mouse up/down while clicking the left mouse button. The model may also be zoomed from under any other command by rotating the mouse wheel (when applicable).

Pan

The model may be panned left, right, up, or down. Upon clicking the button, the cursor with change to a hand; and the view may be panned by moving the mouse while clicking the “left” mouse button. The view may also be panned from under any other command by holding down the middle mouse button/mouse wheel while moving the mouse.

Freehand Markup: FreeHand, Circle, Rectangle, Annotate

Walk Through Gouraud Shading/ Hidden Lines/ Wire Frame/ Two Line Mode/ CenterLine View

On clicking this button, the drop down menu appears with the following options: Free Hand, Circle, Rectangle, and Annotate. The geometry or the text entered by this command, are not kept with the model, and get erased/deleted on any change (like zoom, pan, or rotate).

Allows interactively move inside the model, and look left, right, up, and down. A list of available commands/keys is displayed on the screen. Will switch the corresponding view mode of the model. Pressing the V button on the keyboard will switch the views in following order: Gouraud Shading (rendered mode) -> Two Line Mode > Center Line View.

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Select by Single Click

Clicking on elements when this option is selected causes the input spreadsheet for the chosen element to be displayed in the background. The element is highlighted and zoomed to selection. Additionally, a dialog box with basic element geometry information is updated within the plot window. The Element Information dialog may be moved around or away from the view. Clicking on the empty space will de-select the element. Inserts a cutting plane.

Insert Cutting Plane Annotate Model

When the button is selected the user can add annotations with leader lines to the graphics. This is done by left-clicking the mouse to start the leader line, then dragging the line to the annotation point, typing in the annotation, and then pressing the Enter button. NOTE: The annotation font face, size, and color may be changed by clicking the Change Display Options button.

Model Info

Not active.

Change Display Options

Allows the setting of colors, fonts and other definable defaults for the geometry and text on the plot. Changes to graphic settings are restored whenever plot is exited and restarted in the graphics view. Alternatively, the user may set a "standard" setup to be always restored upon entering graphics for this particular job. This is done through the use of this button, followed by the User Options tab.

Translucent Objects

Enables the see through of elements. The degree of translucence is set in Plot Configuration under the Visibility tab. This option is especially useful when designing a jacketed pipe, when one or more pipes are hidden inside a jacket.

Perspective/ Orthographic/ Stretched Projection

Switches between the named model view projections. The default (set to Orthographic projection) can be set by the user for this particular job through the use of the Plot Configuration dialog, followed by the User Options tab.

Note: Most of the operations are also available by right-clicking the mouse and selecting an action from the popup menu. Pressing [ESC] or re-selecting the option from the popup menu exits the action.

4 Views

Allows viewing all four view modes simultaneously (right, top, front, and ISO). Upon clicking the button, the splitter bars appear, move the mouse to the desired position, and click the left mouse button. NOTE: All four views can be operated on independently (zoom, pan, or orbit); however, the modellevel operations (like selection, coloring for restraints or diameters, node numbers, etc.) update all four views simultaneously. Displays and highlights with color the expansion joints, tees, or flexible nozzles correspondingly.

Expansion Joints/ Tees/ Nozzles Anchors/ Hangers/ Restraints

Displays anchors (alternatively, Menu Plot/Options -> Anchors or “F2” function key), hangers (alternatively, Menu Plot/Options -> Hangers or “F4” function key), and non-anchor, non-hanger restraints (alternatively, Menu Plot/Options -> Restraints or F7 function button) correspondingly. Note: The size of mentioned boundary condition symbols corresponds to the pipe sizing (OD). In addition, the size of restraints and the hangers may be manually adjusted to become larger or smaller by clicking the black arrow to the right of the button and selecting the size option from the drop down menu

Materials/ Diameters/ Wall Thickness/ Insulation

Displays a list of distinct construction materials (keyboard letter “M”), pipe outside diameters (keyboard letter “D”), wall thicknesses (keyboard letter “W”), and/or insulation thicknesses (keyboard letter “I”) used in the model, and colors the corresponding elements on the view with separate colors.

Chapter 3 Piping Screen Reference

, Displacements/ Forces/ Uniform Loads/ WindsWaves View Compass

133

Predefined displacements, Forces and Moments, Uniform Loads, and Wind/Wave loads may be graphically colored on the model. The corresponding legend window is filled with relevant information. The legend window may be dragged away from the viewing area. When printed, the legend in the form of grid is printed on the second page, following the graphics view.

Toggles the display of the coordinate system compass. In addition, the “compass” symbol may be toggled on the screen by typing the letter “P” on the keyboard. Labels plot with node numbers.

Node Numbers

Note: The font face, size and color of the node numbers may be changed by clicking Change Display Options button. In addition, the node numbers may be toggled on the screen by typing the letter N on the keyboard. Labels plot with element lengths.

Lengths

Range

Note: The font face, size and color of the node numbers may be changed by clicking Change Display Options button. In addition, the node numbers may be toggled on the screen by typing the letter L on the keyboard. Displays elements based on node ranges. The dialog allows select all/clear all node numbers, reverse selection, or enter “from” and “to” nodes. Typing U from the keyboard will bring the range dialog out.

View Input Spreadsheet

The View Spreadsheet command allows the user to maintain both the plot and the spreadsheet on the screen simultaneously. If the Select by Single Click button is clicked, the switching among elements in the spreadsheet view will highlight and zoom to the current element on the graphics view.

Show Temperatures/ Pressures

Displays each element temperature or pressure (respectively) as a separate color. If temperature/pressure 2-9 are used, a menu appears allowing the user to choose which temperature/pressure range to display. The legend is displayed in a separate window, that may be dragged away from the view.

Find Node

When clicked, it will display the Find Node dialog . Entering node numbers will select/highlight the element (if found) and move it into the window (zoom to selection)

Note: The current plot may be output to the clipboard, a bitmap file (.TIF), or a printer through use of the Edit-Copy, File-Save As Bitmap, or File-Print commands, respectively.

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Static Output Graphics The user can also use the View-Plot menu command or the Plot toolbar to review the analytic results in graphics mode, which can produce displaced shapes, stress distributions, and restraint actions. The output graphics contains the same 2 toolbars as were used in the input graphics: HOOPS Standard Toolbar – with zoom, pan, orbit and other related buttons, and HOOPS Input Toolbar – with buttons for restraints, materials, diameters, node numbers and other related buttons. See the description of the buttons in the Piping Input Graphics section.

The Hoops Output Options Toolbar is described below:

Load Cases Analysed

This is a drop down list box with a choice of the loads cases that were analyzed for the job. You can switch among available load cases to see the corresponding output.

Deflected Shape

The plot will show the model view along with a normalized/scaled deflected shape of the system in the operating condition for the currently selected load case. The deflection scale can be adjusted by clicking the small black arrow on the right of the button and selecting Adjust Deflection Scale option from the menu. The color of the displaced geometry can be changed by clicking the Change Display Options button on the Hoops Standard Toolbar, and then proceeding to the Output Options tab.

Grow

Not active

Maximum Displacements- X/ Y/ Z

,

Maximum Restraint Loads – FX/ FY/ FZ/ MX/ MY/ MZ

Overstress

Maximum Code Stress

Allows the user to put the actual magnitude for X, Y, or Z displacements on the currently displayed geometry. It starts with highest value for given direction, then (on pressing “Enter”) puts 2nd, 3rd highest, etc. Subsequent clicks of the same button will turn this option off and refresh the plot. Each corresponding element is highlighted on the view. If the Zoom to Selection button is clicked, the view will be zoomed to the highlighted element. If the Show Element Viewer Grid button is clicked, the Event Viewer dialog will be displayed: it contains all the nodes in the model, report is set to Displacements for particular load case, and the corresponding displacements column (DX, DY, or DZ) is highlighted. Allows the user to put the magnitude for forces and moments in selected direction for the restrained nodes. It starts with highest for given option/direction, then (on pressing “Enter”) puts 2nd, 3rd highest, etc. Subsequent clicks of the same button will turn this option off and refresh the plot. Each corresponding element is highlighted on the view. If the Zoom to Selection button is clicked on the toolbar, the view will be zoomed to the highlighted element. If the Show Element Viewer Grid button is clicked r, the Event Viewer dialog will be displayed: it contains all the nodes in the model, report is set to Restraints for particular load case, and the corresponding Force/Moment column is highlighted. Displays with color overstressed points on the elements. Overstressed conditions are only detected for load cases where a code compliance check was done (i.e., where there are allowable stresses available). This operation is similar to Show Code Stress by Percent; but only points with code stress to allowable ratio of greater than 100% are displayed. Displays the code stresses one at a time from the largest to the smallest values. Subsequent clicks of the same button will turn this option off and refresh the plot. Each corresponding element is highlighted on the view. If the Zoom to Selection button is clicked on the toolbar, the view will be zoomed to the highlighted element. If the Show Element Viewer Grid button is clicked, the Event Viewer dialog will be displayed: it contains all the nodes in the model, report is set to Stresses for particular load case, and the Code Stress column is highlighted.

Chapter 3 Piping Screen Reference

Show Code Stress Colors by Value Show Code Stress Colors by Percent Show Element Viewer Grid

Zoom to Selection

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Plots the piping system in a range of colors, where the color corresponds to the value or percent of allowable (respectively) of the code stress. The Legend window can be resized and/or moved away from the view. Colors and corresponding stress levels are initially set in the Configuration/Setup module. They can also be adjusted by clicking the black arrow to the right of the button and selecting Adjust Settings option from the menu.

If the Show Element Viewer Grid button is clicked, the Event Viewer dialog will be displayed whenever any of the Displacements, Restraint Loads, or Stresses buttons is clicked. The Event Viewer Grid contains a selection of load cases analyzed, a set of reports to choose from, all the nodes in the model and other useful information in tabular form. Upon selecting any of the output options buttons, the Event Viewer will be pre-set to the corresponding load case and report. The summary of the reports for any particular element may also be obtained by clicking the Select by Single Click button on the HOOPS Standard Toolbar and pointing to an element on the view. If the Zoom to Selection button is clicked, the view will be zoomed to the highlighted element whenever any of the Displacements, Restraint Loads, or Stress buttons is used. If the button is not “ON”, the elements will still be highlighted, but view will not be zoomed to the selection.

Notes: On operating Output Options buttons (max. displacements, restraint loads, and stresses): (1) Each corresponding element is highlighted on the view. (2) If the Zoom to Selection button is clicked, the view will zoom to the highlighted element. (3) If the Show Element Viewer Grid button is clicked on the toolbar, the Event Viewer dialog will be displayed. It will be pre-set to the corresponding load case and report; column with relevant information and row with selected element will be highlighted on the grid.

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Structural Steel Modeler In This Chapter Overview .....................................................................................2 The Structural Steel Property Editor ...........................................3 General Properties.......................................................................12 UNITS Specification - UNIT ......................................................13 Axis Orientation Vertical ............................................................14 Material Identification - MATID.................................................15 Section Identification - SECID....................................................17 Setting Defaults - DEFAULT......................................................19 Setting Nodes in Space - NODE, NFILL, NGEN .......................20 Building Elements - ELEM, EFILL, EGEN, EDIM....................24 Resetting Element Strong Axis - ANGLE, ORIENT ..................32 End Connection Information .......................................................35 Loads...........................................................................................46 Utilities........................................................................................53 Structural Databases....................................................................54

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Overview The following pages contain descriptions of each of the structural element keywords. These definitions and examples arranged in usage order. The following list of all the keywords is arranged alphabetically and gives the page number for each keyword where its input description can be found. Keyword/Page Number ANGLE (on page 32) BEAMS (on page 38) BRACES (on page 40) COLUMNS (on page 42) DEFAULT (see "Setting Defaults DEFAULT" on page 19) EDIM (on page 29) EFILL (on page 25) EGEN (on page 27) ELEM (on page 24) FIX (see "File Sets" on page 1) FREE (see "File Sets" on page 1) GLOAD (see "Gravity Loads - GLOADS" on page 50) LIST (on page 53) LOAD (see "Point Loads - LOAD" on page 46) MATID (see "Material Identification MATID" on page 15) NFILL (on page 21) NGEN (on page 22) NODE (on page 20) ORIENT (on page 33) SECID (see "Section Identification - SECID" on page 17) UNIF (see "Uniform Load in G's" on page 112) UNIT (see "UNITS Specification - UNIT" on page 13) WIND (see "Wind Loads - WIND" on page 51) VERTICAL (see "Axis Orientation Vertical" on page 14)

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The Structural Steel Property Editor CAESAR II provides the user with the capability to enter the general properties when beginning a new file using the Structural Steel Wizard. The following section illustrates a typical new file input session using this editing technique.

New File

From the CAESAR II Main Menu, select FILE/NEW to begin the process. Type the name of the structural steel file you want to create. To begin this process, click the Structural Input radio button and click OK to launch the Structural Steel Wizard.

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Units File

Select the units file that the structural file will be based on from the pull-down list on this screen. To continue, click Next.

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Vertical Axis

Select either the Y or Z axis as the vertical axis aligned with gravity from the pull-down list on this screen. To continue, click Next.

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Material Properties

Enter the material properties for the structural steel members here before continuing. These include Density, Young's Modulus, Yield Strength, Poisson's Ration, and Thermal Expansion Coefficients. The latter corresponds to operating temperatures 1 through 9 if used. You may have multiple materials using a unique Material ID for each. For additional materials you must complete the wizard first, then continue in the Structural Steel Modeler as instructed later in this chapter. To continue, click Next.

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Cross Section (Section ID)

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Enter the appropriate cross sectional type (note these must be entered exactly as listed at the end of this chapter). An easier method is to click the Select Section ID button and then expand the appropriate tree (beams, channels, tees, or angles) as shown below. All of the cross section types supported by CAESAR II are then available for selection.

After the proper section type is selected click OK. If the section type is to be user-defined, check the User Defined box and enter the data in the area to the right as shown on the next page.

Chapter 4 Structural Steel Modeler

Enter the Cross Sectional Area, Strong and Weak axis moments of inertia, the torsional resistivity constant, and the height and width of the rectangle for plotting purposes. Note: In the plot of a User Defined Cross Section, the section will appear as a simple rectangle with dimensions in BoxH and BoxW. To continue, click Next.

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Model Definition Method

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Select either Type 1 (element Definition using the EDIM commands) or Type 2 (Node and Element Definition using the NODE and ELEM commands). Click Finish to complete the wizard and the main Structural Steel Modeler window appears populated with data from the wizard.

Once this portion of the model is complete you can make further entries as detailed in the following section.

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General Properties All directives are picked from either the menu or the toolbar. After the information is filled out in the input fields on the left side of the window, press the +-sign button to add the command to the model (or drag the dialog to the appropriate position in the text). The appropriate text will appear on the right side of the window (the white section). The following graphics show how to choose the commands, the input fields, and the resultant input file text (always the last line of text on the right). There is no provision to type in commands directly in the text section.

Add Click on the + button to add the data in the edit dialog to the end of the model.

Insert Highlight a given command line in the input list section and click the Insert button to insert the data in the edit dialog in front of the highlighted command.

Replace Click the Replace button to replace the currently highlighted command line with the data in the Edit dialog.

Delete Click the Delete button to remove the highlighted command line from the model. Note:

The data in the Edit dialog may also be dragged to its appropriate position in the model text area.

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UNITS Specification - UNIT

Units Specification

Used to specify the UNITS file to be used, instead of the UNITS file currently designed in the configuration file. This command should appear first, before entering any material, section, or dimensional data.

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Axis Orientation Vertical The axis orientation of the Static Load Case Builder (i.e., wind and wave loads), the Static Output Processor, the Dynamic Input Module, and the Dynamic Output Processor is dictated by the orientation of the model’s input file. Orienting a structural model to Z-Axis Vertical. A new structural model will determine its axis orientation based on the setting in the Configure/Setup module, while an existing structural model will use the same axis orientation under which it was last saved. The axis orientation may be toggled from Y-Axis to Z-Axis button on the Vertical by changing the value of the Vertical command, activated by clicking the toolbar, or through the COMMANDS/MISCELLANEOUS/VERTICAL menu option, as shown in the figure below.

Note: Unlike the piping and equipment files elsewhere in CAESAR II, toggling this setting does not translate the structural input file, but rather physically rotates the model into the new coordinate system. When including structural files in a piping model, the axis orientation of the included files need not match that of the piping model. Translation occurs immediately upon inclusion. When analyzing a structural model on its own, the axis orientation of the Static Load Case Builder (i.e., wind, and wave loads), the Static Output Processor, and the Dynamic Input Processor is dictated by the orientation of the structural model’s input.

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Material Identification - MATID

Material Properties Definition

Used to enter material properties that correspond to a Material ID number.There must be at least one valid material specification given per job. One Material ID can be used for a group of elements that have many Section IDs. (In fact there is usually only a single Material ID specified for any one job.) Units from the specified UNITS.FIL are used. Default material properties (i.e. for A-36 structural steel) may be invoked by issuing the following MATID command: MATID 1.

MATI D

matid,

YM, POIS,

G,

YS,

DENS,

ALPHA

MATID User defined material ID number. Usually 1, and sequentially thereafter.

YM Young’s Modulus of Elasticity.

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POIS Poisson’s Ratio Usually 0.3.

G Shear Modulus of Elasticity Usually about one third of YM

YS Yield Strength (Currently not used)

DENS Material Density

ALPHA Material coefficient of thermal expansion.There can be up to three thermal cases (corresponding to thermal cases T1, T2, and T3) defined for structural steel members. Thermal effects on structural members are entered using thermal expansion coefficients in terms of in./in, mm./mm., i.e. unitless. The three thermal coefficients are entered after the density.

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Section Identification - SECID

Section Definition

Section ID Used to assign member cross section properties to Section ID numbers. SECID secid, NAME =

SECID A user defined Section ID to be used for all future referencing of this set of cross section properties. Usually Section ID’s start at 1 and go up, but the user may assign values in any order that is convenient.

User-Defined For a user-defined shape click the User Defined check box. There are six additional parameters users must enter to fully define the user’s cross section: Area Cross section area (length2). Ixx Strong axis moment of inertia (length4).

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CAESAR II Technical Reference Manual Iyy Weak axis moment of inertia (length4). Torsional R Torsional resistivity constant (length4). BOXH Height of a rectangular box for plotting (height is along the weak axis). BOXW Width of a rectangular box for plotting (width is along the strong axis).

User-Defined Section Properties

Name Either an AISC shape name or the word “USER.” All AISC names should be entered exactly as shown in the AISC handbook with the exception that fractions should be represented as decimals., i.e. the angle: LX6X3-1/2X1/2 should be entered: L6X3.5X0.5. Leading or trailing zeros may be omitted. Alternatively, the user may select the appropriate section name from the window provided after clicking the Select Section ID button. A full list of available Section types are found at the end of this chapter.

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Setting Defaults - DEFAULT

Default Section and Material IDs

Used to set the default values of the Section ID and the Material ID. Whenever an element generation occurs and the Section and/or the Material ID is omitted, the default values set here are used. The initial default value for both the Section and the Material ID is 1.

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Setting Nodes in Space - NODE, NFILL, NGEN NODE

Node Definition

Used to define the absolute coordinates of a point in global X, Y, Z space.

NODE num X, Y, Z

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NFILL

Defining Multiple Nodes along a Line

Used to fill in evenly spaced nodes between two already defined end points. If the increment “BY” is omitted, the default is 1.

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NGEN

Generating a Matrix of Nodes

Used to duplicate patterns of nodes. At least the first and last node in the base node pattern must already exist before the NGEN command is issued. Other nodes in the base node pattern not already defined will be evenly spaced between the first and last node. The DX, DY, and DZ are offsets for duplicate nodes from the base pattern of nodes. NGEN

n1,

TO,

BY,

LAST,

NODEINC,

DX,

DY,

DZ,

n1 First node in the base node pattern (must exist before the NGEN command is issued).

TO Last node in the base node pattern (must exist before the NGEN command is issued).

BY Increment to get from the starting node to the ending node in the base pattern. n1, TO and BY define the nodes in the base pattern. All subsequent nodal patterns generated start from the base pattern. If omitted the default is 1.

LAST Last node in the last nodal pattern to be generated. If omitted then a single pattern duplication will occur.

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NODEINC Increment to get from the nodes in the base pattern to the nodes in the first generated pattern, and then from this pattern to the next generated pattern, etc.

DX, DY, DZ Coordinates offset to get from the nodes in the base pattern to the nodes in the first generated pattern, and then from this pattern to the next generated pattern, etc.

Example In the preceding figure, the nodes from 1100 to 2000 with an increment of 100 are duplicated twice, each new pattern offset 10 ft. in the z-direction. The new nodes created are from 2100 to 3000 and also from 3100 to 4000. Note that the NFILL command previous to this NGEN command was not necessary.

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Building Elements - ELEM, EFILL, EGEN, EDIM ELEM

Defining a Single Element

Used to define a single element that exists between two points in global Cartesian space. In addition a section identifier and a material identifier for the element may also be given. If the section and/or material ids are omitted the current default values are used. (For more information see help for the keyword DEFAULT (see "Setting Defaults - DEFAULT" on page 19).) ELEM

n1,

TO,

SECID,

MATID,

KEYWORD,

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EFILL

Generating Multiple Elements along a Line

Used to generate a consecutive string of elements. None of the elements generated need to exist prior to the FILL operation. EFILL

n1,

TO,

INC,

INCTO,

LAST,

SECID,

MATID,

INCSECID,

INCMATID

n1 “FROM” node number on the first element generated.

TO “TO” node number on the first element generated.

INC Increment to get from the “FROM” node on the first element to the “FROM” node on the second element. If omitted, INC defaults to 1.

INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

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LAST “TO” node on the last element to be generated.

SECID Section ID for the first element generated.

MATID Material ID for the first element generated.

INCSECID Increment to get from the Section ID for the first element to the Section ID for the second element. (Default=0)

INCMATID Increment to get from the Material ID for the first element to the Material ID for the second element. (Default=0)

Example In the preceding figure elements were generated between each pair of nodes between node 1200 and 2000. The increment between From to From nodes and To to To nodes is the same in this case, being equal to 100. Eight elements were created in this example, together with the one element previously created using the ELEM command for a total of nine elements. Note that the ELEM command would not have been necessary here, since all nine elements could have been created using the EFILL command by simply substituting node 1100 in place of node 1200 in the From Node field.

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EGEN

Duplicating Elements

Used to duplicate patterns of elements. EGEN is a very flexible and very powerful generation command that should be used carefully. The form of EGEN shown below does not presume that any of the elements in the base pattern exist before the generation. If elements in the base pattern do exist before the generation they will be redefined during the generation process. EGEN

n1,

TO,

INC,

GENINCTO GENLAST SECID, MATID, , ,

INCTO,

LAST,

INSECID,

INCMATID,

GENINC,

n1 “FROM” node on the first element in the base pattern.

TO “TO” node on the first element in the base pattern.

INC Increment to get from the “FROM” node on the first element in the base pattern to the “FROM” node on the second element in base pattern. If omitted defaults to 1.

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INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

LAST “TO” node on the last element in the base pattern. The EGEN command is set up to generate multiple copies from the base pattern of elements.

GENINC Increment to get from the “FROM” node on the first element in the base pattern to the “FROM” node on the first element in the first duplicate pattern.

GENINCTO Increment to get from the “TO” node on the first element in the base pattern to the “TO” node on the first element in the first duplicate pattern. If omitted defaults to GENINC.

GENLAST The “TO” node on the last element in the last pattern to be duplicated from the base pattern.

SECID Section ID to be used for the elements in the base pattern. If omitted the default Section ID is used. For more information see the “help” for DEFAULT (see "Setting Defaults - DEFAULT" on page 19) for an explanation of how the default Section ID is set up. On start-up the default Section ID is 1.

MATID Material ID to be used for the elements in the base pattern. If omitted the default Material ID is used. For more information see “help” for DEFAULT (see "Setting Defaults - DEFAULT" on page 19) for an explanation of how the default material ID is set up. On start-up the default material ID is 1.

INCSECID Section ID increment to be used between patterns. i.e. the first pattern of elements generated from the base pattern of elements will have a Section ID of SECID + INCSECID. If omitted defaults to zero.

INCMATID Material ID increment to be used between patterns. If omitted defaults to zero.

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Example In the preceding figure the base element pattern from 1100 to 2000 was reproduced two more times, from 2100 to 3000 and from 3100 to 4000. Each element has nodal increments of 100. The increment between the base element list and the next element list is 1000 and the last node in the last pattern is 4000. Then the cross members were created using the base pattern from 1100 to 2100 and reproducing it in nodal increments of 100 until node 4000 was reached. The following figure shows the resultant model.

Volume Plot of Structural Steel Model Showing Node Numbers

EDIM Define elements using the dimensions of the element rather than references to nodes. Any existing elements encountered will be redefined. The EDIM element definition is probably more familiar to piping engineers while ELEM, EGEN, and EFIL are more familiar to structural engineers. INC, INCTO, and LAST may be omitted to define a single element. "FROM" node on the first element to be defined.

TO "To" node on the last element to be defined.

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INC Increment to get from the “FROM” node on the first element to the “FROM” node on the second element. If omitted, INC defaults to 1.

INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

DX, DY, DZ Coordinates offset to get from the nodes in the base pattern to the nodes in the first generated pattern, and then from this pattern to the next generated pattern, etc.

MATID Material ID for the first element. If not given, then the current default is used. (See Help for keyword DEFAULT.)

SECID_EIDM Section ID for the first element. If not given, then the current default is used. (See Help for keyword DEFAULT (see "Setting Defaults - DEFAULT" on page 19).)

INSECID Section ID increment to get from the Section ID of the first element to the Section ID of the second element.

INCMATID_EDIM Material ID increment to get from the Material ID of the first element to the Material ID of the second element.

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Examples EDIM 5 to 10 DY = 12-3 SECID=2..Column 12-3 high from 5 to 10 EDIM 5,10 DY=12-3,2....................Same column EDIM 2 TO 3 LAST=8 DX=13-3.....Defining beams 13-3 long and elements 2-3, 3-4, 4-5, 5-6, 6-7, and 78. INC defaults to 1. <------------> 10-0 (typ)

Enter the 4 EDIM commands top define the small frame shown to the right. Remember that every thing after a (:) or (:) on the line is treated as a comment.

EDIM 1 TO 5 INC=1 LAST=8 DY=12-0 SECID=1

;1st floor columns

EDIM 5 TO 9 INC=1 LAST=12 DY=12-0 SECID=2

;2nd floor columns

EDIM 5 TO 6 INC=1 LAST=8 DX=10-0 SECID=3

;1st floor beams

EDIM 9 TO 10 INC=1 LAST=12 DX=10-0 SECID=3

;roof beams

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Resetting Element Strong Axis - ANGLE, ORIENT ANGLE

Defining the Default Strong Axis Orientation

Used to define the default element strong axis orientation. ANGLE is most often used when defining columns whose strong axes are not parallel to the X axis. (Usually for columns the strong axis is parallel to either the X or the Z axis.) In the case where the column strong axis is parallel to the Z axis, first ANGLE is used to redefine the default orientation, i.e. ANGLE=90. Next the column elements are defined. Then ANGLE is used again to reset the default orientation back to its original value, i.e. ANGLE=0.0. The ORIENT and ANGLE keywords similarly define the angle of rotation (in degrees) about the element center line from the standard orientation to the element strong axis. ORIENT defines this angle for a single element or for a group of elements, and ANGLE sets the default orientation back to its original value, i.e. ANGLE=0.0. The default orientation angle is zero degrees. Positive angular rotation is found using the “right-hand rule” by extending the thumb along the element in the direction of the “TO” node. The fingers of the right hand circle in the direction of a positive orientation angle. The default element orientation is as follows: If the member is vertical then the default strong axis is taken to be along the global X axis.

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For all non-vertical members the strong axis is taken to be perpendicular to the center line of the member and in the horizontal plane. (This is exactly what is desired for a typical beam orientation in a building). The strong axis is defined for the WF shape as shown:

ANGLE

n1

n1 Default strong axis orientation angle to be used for all subsequently defined elements.

ORIENT Used to define the element strong axis orientation. Note that values for n1 and “TO” may be given as node numbers or element indices. Element indices are enclosed in parentheses. An example of the index input is given at the bottom.

ORIENT

n1,

TO

INC,

INCTO, LAST, ANGLE,

n1 “FROM” node on the first element.

TO “TO” node on the first element.

INC Increment to get from the “FROM” node on the first element to the “FROM” node on the second element. If omitted, INC defaults to 1.

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INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

n1 “FROM” node on the first element the wind load is to act on.

LAST “TO” node on the last element to have its orientation angle defined.

ANGLE Rotation in degrees from the default position to the actual position of the member strong axis.

Examples ORIENT 1 TO 2 ANGLE=90 The strong axis for the element from 1 to 2 is 90 degrees away from the default position. ORIENT 5 TO 10 INC=5 LAST=30 ANGLE=90 The elements: 5-10, 10-15, 15-20, 20-25, and 25-30 all have their strong axis 90 degrees away from the default position. If each of these members is a vertical column, then their new strong axis of bending is along the Z axis. (This means that the columns with their new orientation are better suited to take X direction forces.)

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End Connection Information Free End Connections - FREE

Auxiliary Data Area for Defining Free End Connections

Used to define element “FREE” end connections. For example FREE would be used to describe the element ends in a structure that has “pinned-only” beam-to-column connections. “End connection type” defines a members fixity to its nodes, not a nodes fixity in space. FREE works in conjunction with “BEAMS,” ”BRACES,” and “COLUMNS.” These last three keywords are used to set the “FREE” end connection defaults for certain types of members. For each element defined after the defaults are set an entry is automatically made into the “FREE” array to keep track of the type of connection and the nodes that define the element. FREE

n1,

TO,

INC,

INCTO,

n1 “FROM” node on the first element that this FREE spec is to apply to.

TO “TO” node on the first element that this FREE spec is to apply to.

LAST,



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CAESAR II Technical Reference Manual

INC Increment to get from the “FROM” node on the first element to the “FROM” node on the second element. If omitted, INC defaults to 1.

INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

LAST “TO” node on the last element this FREE spec is to apply to. LAST, INC, and INCTO can be omitted if the FREE spec is only to apply to a single element. - May be any single combination of: /————At the element FROM end ————/ FAXIAL

-

Axial translational dof

FSHRSTR

-

Strong axis shear translational dof

FSHRWEAK

-

Weak axis shear translational dof

FTORS

-

Torsional dof

FBNDSTR

-

Strong axis bending dof

FBNDWEAK

-

Weak axis bending dof

/————At the element TO end —————/ TAXIAL

-

Axial translational dof

TSHRSTR

-

Strong axis shear translational dof

TSHRWEAK

-

Weak axis shear translational dof

TTORS

-

Torsional dof

TBNDSTR

-

Strong axis bending dof

TBNDWEAK

-

Weak axis bending dof

Enter those that define the degrees of freedom at the element end that should be “FREE.” In the case where a small WF shape attaches to a large I beam the connection might be designed so that weak axis bending of the WF shape is not transmitted to the web of the I beam. If the element defining the WF shape went from nodes 1040 to 1045 then the “FREE” spec for this element might appear: FREE 1040 TO 1045 FBNDWEAK, TBNDWEAK

Chapter 4 Structural Steel Modeler

37

The westward side of a building has a row of beams on the ground floor that are attached rigidly to columns at the other end. The beams are identified by the pattern of nodes: 610-710, 620-720, 630-730, ...,690-790. There are eight beams in all in this group. The 600 end is the end that is pinned. The FREE spec for this group might appear: FREE 610 TO 710 INC=10

LAST=790

FTORS, FBNDSTR, FBNDWEAK

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CAESAR II Technical Reference Manual

Standard Structural Element Connections - BEAMS, BRACES, COLUMNS BEAMS

Auxiliary Data Area for Defining Default End Connections for BEAMS

Defines default end connection types for members identified by the orientation of their center line. The definition of BEAM is any member whose center line lies completely along either the global X or global Z axis. Once the BEAMS keyword is used to define element end connection freedoms any element subsequently defined that fits the above definition for a beam will have those same end connection freedoms. This will continue until the BEAMS keyword is reset or re-specified. The default condition is for each end of any member to be fixed in all six degrees of freedom to its nodes. BEAMS has two possible setting modes: FIX and FREE. The FREE mode is to set “FREE” end connection defaults, and the FIX mode is to reset the end connection types once all beams with that particular “FREE” end connection have been defined. BEAMS FREE

...use to release end connections.

BEAMS FIX

...use to reset released-end connections

The are discussed in greater detail with the “FREE” keyword. The defining the 12 local degrees of freedom for each element are: FAXIAL

TAXIAL

FSHRSTR

TSHRSTR

FSHRWEAK

TSHRWEAK

Chapter 4 Structural Steel Modeler

FTORS

TTORS

FBNDSTR

TBNDSTR

FBNDWEAK

TBNDWEAK

39

Example Just before defining a group of beams that had both ends pinned, the following BEAMS command would be issued: BEAMSFREE FTORS,

FBNDSTR, FBNDWEAK, TBNDSTR,

TBNDWEAK,

Just after defining the pinned end beams, to return the end connection defaults to their regular values the following BEAMS command would be issued: BEAMSFIX

FTORS,

FBNDSTR, FBNDWEAK, TBNDSTR,

TBNDWEAK,

As shorthand notation, if the word “FIX” is all that appears on the line following “BEAMS,” then all end connections for the beam will be fixed, i.e. BEAMS FIX

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CAESAR II Technical Reference Manual

BRACES

Auxiliary Area for Defining Default End Connections for Braces Used to define default end connection types for members that can be identified by the orientation of their center line. The definition of BRACE in-so-far as this keyword is concerned, is any member whose center line does not completely lie along any of the global axes. Once the BRACE keyword is used to define element end connection freedoms any element subsequently defined that fits the above definition for a brace will have those same end connection freedoms. This will continue until the BRACE keyword is reset or re-specified. The default condition is for each end of any member to be fixed in all six degrees of freedom to its nodes. BRACES may be abbreviated: BR. BRACES has two possible setting modes: FIX and FREE. The FREE mode is used to set “FREE” end connection defaults, and the FIX mode is used to reset the end connection types once all braces with that particular “FREE” end connection have been defined. BRACES FREE ...use to release end connections BRACES FIX ...use to reset released end connections The are discussed in greater detail with the “FREE” keyword. The defining the 12 local degrees of freedom for each element are: FAXIAL

TAXIAL

FSHRSTR

TSHRSTR

FSHRWEAK

TSHRWEAK

Chapter 4 Structural Steel Modeler

FTORS

TTORS

FBNDSTR

TBNDSTR

FBNDWEAK

TBNDWEAK

41

Example Just before defining a group of braces that had both ends pinned to the adjoining columns, the following command would be issued:

BRACES

BRACES FREE

FTORS,

FBNDSTR,

FBNDWEAK, TBNDSTR,

TBNDWEAK,

Just after defining the pinned end braces, to return the end connection defaults to their regular values the following BRACES command would be issued. BRACESFIX

FTORS,

FBNDSTR, FBNDWEAK, TBNDSTR,

TBNDWEAK,

As shorthand notation, if the word “FIX” is all that appears on the line following “BRACES,” then all end connections for the brace will be fixed, i.e. BRACES FIX

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CAESAR II Technical Reference Manual

COLUMNS

Auxiliary Data Area for Defining Default End Connections for Columns Used to define default end connection types for members that can be identified by the orientation of their center line. The definition of COLUMN in-so-far as this keyword is concerned is any member whose center line is completely vertical. Once the COLUMN keyword is used to define element end connection freedoms any element subsequently defined that fits the above definition for a column will have those same end connection freedoms. This will continue until the COLUMN keyword is reset or re-specified. The default condition is for each end of any member to be fixed in all six degrees of freedom to its nodes. COLUMNS has two possible setting modes: FIX and FREE. The FREE mode is to set “FREE” end connection defaults, and the FIX mode is to reset the end connection types once all columns with that particular “FREE” end connection have been defined. COLUMNS FREE ..use to release end connections COLUMNS FIX ..use to reset released end connections The are discussed in greater detail with the “FREE” keyword. The that define the 12 local element degrees of freedom are: FAXIAL

TAXIAL

FSHRSTR

TSHRSTR

FSHRWEAK

TSHRWEAK

Chapter 4 Structural Steel Modeler

FTORS

TTORS

FBNDSTR

TBNDSTR

FBNDWEAK

TBNDWEAK

43

Example Just before defining a group of corner columns that were pinned at their “TO” ends, the following COLUMN command would be issued: COLUMNSFREE TTORS, TBNDSTR TBNDWEAK, ,

TBNDSTR,

TBNDWEAK,

Just after defining the pinned end columns, to return the end connection defaults to their regular values the following COLUMNS command would be issued: COLUMNSSFREE TTORS,

TBNDSTR TBNDWEAK, TBNDSTR, ,

TBNDWEAK,

As shorthand notation, if the word “FIX” is all that appears on the line following “COLUMNS”, then all end connections for the column will be fixed, i.e. COLUMNS FIX Note: As a general rule an element cannot undergo rigid body motion. Therefore, an element can not have both TTORS and FTORS released at the same time. Additionally beams typically have moment releases only at their ends, not at intermediate nodes used to apply loads or connect bracing.

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CAESAR II Technical Reference Manual

Defining Global Restraints - FIX

Auxiliary Data Area for Defining Restraints

Used to define restraint boundary conditions at structural member end points. Stiffnesses may be entered in the field following the fixity indicator; if the stiffness value is omitted, the fixity will be rigid. “TO” and “BY” may be omitted to define the fixity for a single node point. (i.e. FIX 10 ALL) Note that values for n1 and “TO” may be given as node numbers or indices. Node indices are enclosed in parenthesis. FIX

FIX

n1,

n1,

TO,

BY,

X,

Y,

Z,

RX,

n2,

n3,

n4,

n5,

n6,

n7,

RY,

n8,

RZ,

n9,

n10,

ALL

Chapter 4 Structural Steel Modeler

45

Examples FIX 1 ALL - Fix all degrees of freedom at node #1. FIX 5 X1000 Y1000 Z1000 Fix X, Y and Z degrees of freedom at node #5, and use 1,000 lb./in. springs FIX 100 TO 110 ALL Fix rigidly all degrees of freedom for the nodes from 100 to 110. The increment between 100 and 110 defaults to 1. Eleven nodes have their fixities defined here. FIX 105 TO 125 BY 5 X1000,1000,1000 Fix X, Y, and Z degrees of freedom for the nodes: 105, 110, 115, 120, and 125, and use 1,000 lb./in. springs. FIX (1) to (10) ALL Fix all degrees of freedom for the first 10 nodes in the node list.

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CAESAR II Technical Reference Manual

Loads Point Loads - LOAD

Auxiliary Data Area for Defining Concentrated Forces and Moments

Used to define concentrated forces and/or moments that act at structural member end points. “TO” and “BY” may be omitted to define loads for a single point. LOAD may be abbreviated: LOA. Note that values for n1 and “TO” may be given as node numbers or indices. Node indices are enclosed in parentheses. LOAD

n1,

TO,

BY,

LOAD

n1,

n2,

n3,

FX,

n4,

FY,

n5,

FZ,

n6,

MX,

MY,

n7,

n8,

Chapter 4 Structural Steel Modeler

47

Examples LOAD 305 FY-1000 Have minus 1,000 lb. Y direction load acting at the structural node #305. LOAD 10 TO 18 BY=1 FX=707,FZ=707 Have skewed load in the horizontal plane acting at each of the nodes 10,11,...,17,18. “BY” could have been omitted here, its default is 1. LOAD (15) to (25) FY=-383 A load of 383 pounds acts in the minus Y direction on the 15’th through the 25’th nodes in the node list.

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CAESAR II Technical Reference Manual

Uniform Loads - UNIF

Auxiliary Data Area for Defining Uniform Loads

Used to define a constant uniform load (i.e., CAESAR II load case U1) that acts over the full length of the member. (Uniform loads may have special meanings when used in CAESAR II piping runs.) “INC,” “INCTO,” and “LAST” may be omitted to define a uniform loading that acts on a single element only. Note that values for n1 and “TO” may be given as node numbers or element indices. Element indices are enclosed in parentheses. UNIF

n1,

TO,

INC,

UNIF

n1,

n2,

n3,

INCTO

n4,

LAST

n5,

n6,

UX,

UY, UZ,

n7,

n8,

n1 “FROM” node on the first element this uniform load is to act on.

TO “TO” node on the first element this uniform load is to act on.

Chapter 4 Structural Steel Modeler

49

INC Increment to get from the “FROM” node on the first element to the “FROM” node on the second element. If omitted, INC defaults to 1.

INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

LAST “TO” node on the last element this uniform load is to act on.

UX,UY,UZ Magnitude of the uniform load in the global X, Y and Z directions. Unless used in a piping analysis employing “g” loads, uniform loads are in units of force per unit length of member. When used in a piping analysis with “g” loads the uniform loads are in units of gravitational acceleration., i.e. UY=-1 would define a uniform load identical to the member weight load.

Examples UNIF 1 TO 2 UY=-2.3 On the element from 1 to 2 a uniform load with a magnitude of 2.3 lbs. per inch acts in the minus Y direction. UNIF 1,2, UY -2,3 Same UNIF 100 TO 200 INC=2 INCTO=3 LAST=500 UX=0.03, -1,0.03 Uniform load acting on elements 100-200, 102-203,...,300-500 with a small horizontal component and a -1 load in the Y. (Looks like have “g” load input for piping problem.) UNIF (1) to (30) UY=-2.3 The first 30 elements in the element list have a uniform load of -2.3 pounds per inch acting in the minus Y direction.

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CAESAR II Technical Reference Manual

Gravity Loads - GLOADS

Defining Uniform Load in G’s

Used to inform this processor that all specified uniform loads are to be interpreted as “G” loads instead of force/length. Important: If structural and piping models are mixed the GLOAD flags must match (i.e., uniform loads in the piping model must be designed as "G" loads in the special execution parameters). This command takes no other parameters.

Chapter 4 Structural Steel Modeler

51

Wind Loads - WIND

Defining Wind Loads

Defines the magnitude of the wind shape factor for the structural elements. (The default value is 2.0.) WIND

n1,

TO,

INC,

WIND

n1,

n2,

n3,

INCTO,

n4,

n5,

LAST,

n6,

SHAPE,

n7,

n8,

n1 “FROM” node on the first element the wind load is to act on.

TO “TO” node on the first element the wind load is to act on.

INC Increment to get from the “FROM” node on the first element to the “FROM” node on the second element. If omitted, INC defaults to 1.

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CAESAR II Technical Reference Manual

INCTO Increment to get from the “TO” node on the first element to the “TO” node on the second element. If INCTO is not given, it defaults to INC.

LAST “TO” node on the last element the wind load is to act on.

SHAPE Magnitude of the wind shape factor. For structural steel members this value is usually 2.0. Wind loading on the structure can be turned on and off by resetting this parameter to zero, for elements not exposed to the wind. This value carries forward to all subsequently defined elements.

Examples WIND 1 TO 2 SHAPE=2.0 On the element from 1 to 2 a shape factor with a magnitude of 2.0 is applied. This value is applied to all following elements. WIND 1,2,SHAPE 2.0 Same WIND 100 TO 200 INC=2 INCTO=3 LAST=500 SHAPE=1.8 Wind shape factor of 1.8 on elements 100-200, 102-203,...,300-500.

Chapter 4 Structural Steel Modeler

53

Utilities LIST To access the List option, click the List tab located at the bottom of the Structural Steel Modeler. List enables users to display node and coordinate data; enter node ranges; and also select input list reports. Note, selecting all displays a of each report in the order they appear on the modeler window.

Defining List Options to Display

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CAESAR II Technical Reference Manual

Structural Databases The CAESAR II Structural databases contain over 20 different properties for each cross section. For the finite element solution, only six of these items are employed: Area Strong axis moment of inertia Weak axis moment of inertia Torsional resistivity constant Member section height Member section depth There are seven different structural databases included in CAESAR II. The databases are those of the AISC 1977, the AISC 1989, the German 1991, the Australian 1990, the South African 1992, Korean 1990, and UK 1993. The member designations for each database are listed as follows:

Chapter 4 Structural Steel Modeler

AISC 1977 Database W36X300

W36X280

W36X260

W36X245

W36X230

W36X210

W36X194

W36X182

W36X170

W36X160

W36X150

W36X135

W33X241

W33X221

W33X201

W33X152

W33X141

W33X130

W33X118

W30X211

W30X191

W30X173

W30X132

W30X124

W30X116

W30X108

W30X99

W27X178

W27X161

W27X146

W27X114

W27X102

W27X94

W27X84

W24X162

W24X146

W24X131

W24X117

W24X104

W24X94

W24X84

W24X76

W24X68

W24X62

W24X55

W21X147

W21X132

W21X122

W21X111

W21X101

W21X93

W21X83

W21X73

W21X68

W21X62

W21X57

W21X50

W21X44

W18X119

W18X106

W18X97

W18X86

W18X76

W18X71

W18X65

W18X60

W18X55

W18X50

W18X46

W18X40

W18X35

W16X100

W16X89

W16X77

W16X67

W16X57

W16X50

W16X45

W16X40

W16X36

W16X31

W16X26

W14X730

W14X665

W14X605

W14X550

W14X500

W14X455

W14X426

W14X398

W14X370

W14X342

W14X311

W14X283

W14X257

W14X233

W14X211

W14X193

W14X176

W14X159

W14X145

W14X132

W14X120

W14X109

W14X99

W14X90

W14X82

W14X74

W14X68

W14X61

W14X53

W14X48

W14X43

W14X38

W14X34

W14X30

W14X26

W14X22

W12X336

W12X305

W12X279

W12X252

W12X230

W12X210

W12X190

W12X170

W12X152

W12X136

W12X120

W12X106

W12X96

W12X87

W12X79

W12X72

W12X65

W12X58

W12X53

W12X50

W12X45

W12X40

W12X35

W12X30

W12X26

W12X22

W12X19

W12X16

W12X14

W10X112

W10X100

W10X88

W10X77

W10X68

W10X60

W10X54

W10X49

W10X45

W10X39

W10X33

W10X30

W10X26

W10X22

W10X19

W10X17

W10X15

W10X12

W8X67

W8X58

W8X48

W8X40

W8X35

W8X31

W8X28

W8X24

W8X21

W8X18

W8X15

W8X13

W8X10

W6X25

W6X20

W6X16

W6X15

W6X12

W6X9

W5X19

W5X16

55

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CAESAR II Technical Reference Manual

W4X13

M14X18

M12X11.8

M10X9

M8X6.5

M6X20

M6X4.4

M5X18.9

M4X13

S24X121

S24X106

S24X100

S24X90

S24X80

S20X96

S20X86

S20X75

S20X66

S18X70

S18X54.7

S15X50

S15X42.9

S12X50

S12X40.8

S12X35

S12X31.8

S10X35

S10X25.4

S8X23

S8X18.4

S7X20

S7X15.3

S6X17.2

S6X12.5

S5X14.7

S5X10

S4X9.5

S4X7.7

S3X7.5

S3X5.7

C15X50

C15X40

C15X33.9

C12X30

C12X25

C12X20.7

C10X30

C10X25

C10X20

C10X15.3

C9X20

C9X15

C9X13.4

C8X18.7

C8X13.7

C8X11.5

C7X14.7

C7X12.2

C7X9.8

C6X13

C6X10.5

C6X8.2

C5X9

C5X6.7

C4X7.25

C4X5.4

C3X6

C3X5

C3X4.1

MC18X58

MC18X51.9

MC18X45.8

MC18X42.7

MC13X50

MC13X40

MC13X35

MC13X31.8

MC12X50

MC12X45

MC12X40

MC12X35

MC12X37

MC12X32.9

MC12X30.9

MC12X10.6

MC10X41.1

MC10X33.6

MC10X28.5

MC10X28.3

MC10X25.3

MC10X24.9

MC10X21.9

MC10X8.4

MC10X6.5

MC9X25.4

MC9X23.9

MC8X22.8

MC8X21.4

MC8X20

MC8X18.7

MC8X8.5

MC7X22.7

MC7X19.1

MC7X17.6

MC6X18

MC6X15.3

MC6X16.3

MC6X15.1

MC6X12

WT18X150

WT18X140

WT18X130

WT18X122.5

WT18X115

WT18X105

WT18X97

WT18X91

WT18X85

WT18X80

WT18X75

WT18X67.5

WT16.5X120.5

WT16.6X110.5

WT16.5X100.5

WT16.5X76

WT16.5X70.5

WT16.5X65

WT16.5X59

WT15X105.5

Chapter 4 Structural Steel Modeler

WT15X95.5

WT15X86.5

WT15X66

WT15X62

WT15X58

WT15X54

WT15X49.5

WT13.5X89

WT13.5X80.5

WT13.5X73

WT13.5X57

WT13.5X51

WT13.5X47

WT13.5X42

WT12X81

WT12X73

WT12X65.5

WT12X58.5

WT12X52

WT12X47

WT12X42

WT12X38

WT12X34

WT12X31

WT12X27.5

WT10.5X73.5

WT10.5X66

WT10.5X61

WT10.5X55.5

WT10.5X50.5

WT10.5X46.5

WT10.5X41.5

WT10.5X36.5

WT10.5X34

WT10.5X31

WT10.5X28.5

WT10.5X25

WT10.5X22

WT9X59.5

WT9X53

WT9X48.5

WT9X43

WT9X38

WT9X35.5

WT9X32.5

WT9X30

WT9X27.5

WT9X25

WT9X23

WT9X20

WT9X17.5

WT8X50

WT8X44.5

WT8X38.5

WT8X33.5

WT8X28.5

WT8X25

WT8X22.5

WT8X20

WT8X18

WT8X15.5

WT8X13

WT7X365

WT7X332.5

WT7X302.5

WT7X275

WT7X250

WT7X227.5

WT7X213

WT7X199

WT7X185

WT7X171

WT7X155.5

WT7X141.5

WT7X128.5

WT7X116.5

WT7X105.5

WT7X96.5

WT7X88

WT7X79.5

WT7X72.5

WT7X66

WT7X60

WT7X54.5

WT7X49.5

WT7X45

WT7X41

WT7X37

WT7X34

WT7X30.5

WT7X26.5

WT7X24

WT7X21.5

WT7X19

WT7X17

WT7X15

WT7X13

WT7X11

WT6X168

WT6X152.5

WT6X139.5

WT6X126

WT6X115

WT6X105

WT6X95

WT6X85

WT6X76

WT6X68

WT6X60

WT6X53

WT6X48

WT6X43.5

WT6X39.5

WT6X36

WT6X32.5

WT6X29

WT6X26.5

WT6X25

WT6X22.5

WT6X20

WT6X17.5

WT6X15

WT6X13

WT6X11

WT6X9.5

WT6X8

WT6X7

WT5X56

WT5X50

WT5X44

WT5X38.5

WT5X34

WT5X30

WT5X27

WT5X24.5

WT5X22.5

WT5X19.5

WT5X16.5

WT5X15

WT5X13

WT5X11

WT5X9.5

WT5X8.5

WT5X7.5

WT5X6

WT4X33.5

WT4X29

WT4X24

WT4X20

57

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CAESAR II Technical Reference Manual

WT4X17.5

WT4X15.5

WT4X14

WT4X12

WT4X10.5

WT4X9

WT4X7.5

WT4X6.5

WT4X5

WT4X12.5

WT4X10

WT4X7.5

WT3X8

WT3X6

WT3X4.5

WT2.5X9.5

WT2.5X8

WT2X6.5

MT7X9

MT6X5.9

MT5X4.5

MT4X3.25

MT3X10

MT3X2.2

MT2.5X9.45

MT2X6.5

ST12X60.5

ST12X53

ST12X50

ST12X45

ST12X40

ST10X48

ST10X43

ST10X37.5

ST10X33

ST9X35

ST9X27.35

ST7.5X25

ST7.5X21.45

ST6X25

ST6X20.4

ST6X17.5

ST6X15.9

ST5X17.5

ST5X12.7

ST4X11.5

ST4X9.2

ST3.5X10

ST3.5X7.65

ST3X8.625

ST3X6.25

ST2.5X7.375

ST2.5X5

ST2X4.75

ST2X3.85

ST1.5X3.75

ST1.5X2.85

Double angles - long legs back-to-back

D8X8X1.1250

D8X8X1.0000

D8X8X0.8750

D8X8X0.7500

D8X8X0.6250

D8X8X0.5000

D6X6X1.0000

D6X6X0.8750

D6X6X0.7500

D6X6X0.6250

D6X6X0.5000

D6X6X0.3750

D5X5X0.8750

D5X5X0.7500

D5X5X0.5000

D5X5X0.3750

D5X5X0.3125

D4X4X0.7500

D4X4X0.6250

D4X4X0.5000

D4X4X0.3750

D4X4X0.3125

D4X4X0.2500

D3.5X3.5X0.3750

D3.5X3.5X0.3125

D3.5X3.5X0.2500

D3X3X0.5000

D3X3X0.3750

D3X3X0.3125

D3X3X0.2500

D3X3X0.1875

D2.5X2.5X0.3750

D2.5X2.5X0.3125

D2.5X2.5X0.2500

D2.5X2.5X0.1875

D2X2X0.3750

D2X2X0.3125

D2X2X0.2500

D2X2X0.1875

D2X2X0.1250

D8X6X1.0000

D8X6X0.7500

Chapter 4 Structural Steel Modeler

D8X6X0.5000

D8X4X1.0000

D8X4X0.7500

D8X4X0.5000

D7X4X0.7500

D7X4X0.5000

D7X4X0.3750

D6X4X0.7500

D6X4X0.6250

D6X4X0.5000

D6X4X0.3750

D6X3.5X0.3750

D6X3.5X0.3125

D5X3.5X0.7500

D5X3.5X0.5000

D5X3.5X0.3750

D5X3.5X0.3125

D5X3X0.5000

D5X3X0.3750

D5X3X0.3125

D5X3X0.2500

D4X3.5X0.5000

D4X3.5X0.3750

D4X3.5X0.3125

D4X3.5X0.2500

D4X3X0.5000

D4X3X0.3750

D4X3X0.3125

D4X3X0.2500

D3.5X3X0.3750

D3.5X3X0.3125

D3.5X3X0.2500

D3.5X2.5X0.3750

D3.5X2.5X0.3125

D3.5X2.5X0.2500

D3X2.5X0.3750

D3X2.5X0.2500

D3X2.5X0.1875

D3X2X0.3750

D3X2X0.3125

D3X2X0.2500

D3X2X0.1875

D2.5X2X0.3750

D2.5X2X0.3750

D2.5X2X0.2500

D2.5X2X0.1875

B8X6X1.0000

B8X6X0.7500

Double angles small legs back-to-back

B8X6X1.0000

B8X6X0.7500

B8X6X0.2500

B8X4X1.0000

B8X4X0.7500

B8X4X0.5000

B7X4X0.7500

B7X4X0.5000

B7X4X0.3750

B6X4X0.7500

B6X4X0.6250

B6X4X0.5000

B6X4X0.3750

B6X3.5X0.3750

B6X3.5X0.3125

B5X3.5X0.7500

B5X3.5X0.5000

B5X3.5X0.3750

B5X3.5X0.3125

B5X3X0.5000

B5X3X0.3750

B5X3XO.3125

B5X3X0.2500

B4X3.5X0.5000

B4X3.5X0.3750

B4X3.5X0.3125

B4X3.5X0.2500

B4X3X0.5000

B4X3X0.3750

B4X3X0.3125

B4X3X0.2500

B3.5X3X0.3750

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CAESAR II Technical Reference Manual

B3.5X3X0.3125

B3.5X3X0.2500

B3.5X2.5X0.3750

B3.5X2.5X0.3125

B3.5X2.5X0.2500

B3X2.5X0.3750

B3X2.5X0.2500

B3X2.5X0.1875

B3X2X0.3750

B3X2X0.3125

B3X2X0.2500

B3X2X0.1875

B2.5X2X0.3750

B2.5X2X0.3125

B2.5X2X0.2500

B2.5X2X0.1875

Chapter 4 Structural Steel Modeler

AISC 1989 Database W44X285

W44X248

W44X224

W44X198

W40X328

W40X298

W40X268

W40X244

W40X221

W40X192

W40X655

W40X593

W40X531

W40X480

W40X436

W40X397

W40X362

W40X324

W40X297

W40X277

W40X249

W40X215

W40X199

W40X183

W40X167

W40X149

W36X848

W36X798

W36X720

W36X650

W36X588

W36X527

W36X485

W36X439

W36X393

W36X359

W36X328

W36X300

W36X280

W36X260

W36X245

W36X230

W36X256

W36X232

W36X210

W36X194

W36X182

W36X170

W36X160

W36X150

W36X135

W33X619

W33X567

W33X515

W33X468

W33X424

W33X387

W33X354

W33X318

W33X291

W33X263

W33X241

W33X221

W33X201

W33X169

W33X152

W33X141

W33X130

W33X118

W30X581

W30X526

W30X477

W30X433

W30X391

W30X357

W30X326

W30X292

W30X261

W30X235

W30X211

W30X191

W30X173

W30X148

W30X132

W30X124

W30X116

W30X108

W30X99

W30X90

W27X539

W27X494

W27X448

W27X407

W27X368

W27X336

W27X307

W27X281

W27X258

W27X235

W27X217

W27X194

W27X178

W27X161

W27X146

W27X114

W27X102

W27X94

W27X84

W24X492

W24X450

W24X408

W24X370

W24X335

W24X306

W24X279

W24X250

W24X229

W24X207

W24X192

W24X176

W24X162

W24X146

W24X131

W24X117

W24X104

W24X103

W24X94

W24X84

W24X76

W24X68

W24X62

W24X55

W21X402

W21X364

W21X333

W21X300

W21X275

W21X248

W21X223

W21X201

W21X182

W21X166

W21X147

W21X132

W21X122

W21X111

W21X101

W21X93

W21X83

W21X73

W21X68

W21X62

W21X57

W21X50

W21X44

W18X311

W18X283

W18X258

W18X234

W18X211

W18X192

W18X175

W18X158

W18X143

W18X130

W18X119

W18X106

W18X97

W18X86

W18X76

W18X71

W18X65

W18X60

W18X55

W18X50

W18X46

W18X40

W18X35

W16X100

W16X89

61

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CAESAR II Technical Reference Manual

W16X77

W16X67

W16X57

W16X50

W16X45

W16X40

W16X36

W16X31

W16X26

W14X730

W14X665

W14X605

W14X550

W14X500

W14X455

W14X426

W14X398

W14X370

W14X342

W14X311

W14X283

W14X257

W14X233

W14X211

W14X193

W14X176

W14X159

W14X145

W14X132

W14X120

W14X109

W14X99

W14X90

W14X82

W14X74

W14X68

W14X61

W14X53

W14X48

W14X43

W14X38

W14X34

W14X30

W14X26

W14X22

W12X336

W12X305

W12X279

W12X252

W12X230

W12X210

W12X190

W12X170

W12X152

W12X136

W12X120

W12X106

W12X96

W12X87

W12X79

W12X72

W12X65

W12X58

W12X53

W12X50

W12X45

W12X40

W12X35

W12X30

W12X26

W12X22

W12X19

W12X16

W12X14

W10X112

W10X100

W10X88

W10X77

W10X68

W10X60

W10X54

W10X49

W10X45

W10X39

W10X33

W10X30

W10X26

W10X22

W10X19

W10X17

W10X15

W10X12

W8X67

W8X58

W8X48

W8X40

HP14X117

HP14X102

HP14X89

HP14X73

HP13X100

HP13X87

HP13X73

HP13X60

HP12X84

HP12X74

HP12X63

HP12X53

HP10X57

HP10X42

HP8X36

M14X18

M12X11.8

M10X9

M8X6.5

M6X20

M6X4.4

S24X121

S24X106

S24X100

S24X90

S24X80

S20X96

S20X86

S20X75

S20X66

S18X70

S18X54.7

S15X50

S15X42.9

S12X50

S12X40.8

S12X35

S12X31.8

S10X35

S10X25.4

S8X23

S8X18.4

S7X20

S7X15.3

S6X17.25

S6X12.5

S5X14.75

S5X10

S4X9.5

S4X7.7

S3X7.5

C15X50

C15X40

C15X33.9

C12X30

C12X25

C12X20.7

C10X30

C10X25

C10X20

C10X15.3

C9X20

C9X15

S3X5.7

M5X18.9

M4X13

Chapter 4 Structural Steel Modeler

C9X13.4

C8X18.75

C8X13.75

C8X11.5

C7X14.75

C7X12.25

C7X9.8

C6X13

C6X10.5

C6X8.2

C5X9

C5X6.7

C4X7.25

C4X5.4

C3X6

C3X5

C3X4.1

MC18X58

MC18X51.9

MC18X45.8

MC18X42.7

MC13X50

MC13X40

MC13X35

MC13X31.8

MC12X50

MC12X45

MC12X40

MC12X35

MC12X31

MC12X10.6

MC10X41.1

MC10X33.6

MC10X28.5

MC10X25

MC10X22

MC10X8.4

MC10X6.5

MC9X25.4

MC9X23.9

MC8X22.8

MC8X21.4

MC8X20

MC8X18.7

MC8X8.5

MC7X22.7

MC7X19.1

MC6X18

MC6X15.3

MC6X16.3

MC6X15.1

MC6X12

WT18X115

WT18X128

WT18X116

WT18X105

WT18X97

WT18X91

WT18X85

WT18X80

WT18X75

WT18X67.5

WT16.5X177

WT16.5X159

WT16.5X145.5

WT16.5X131.5

WT16.5X120.5

WT16.5X110.5

WT16.5X100.5

WT16.5X84.5

WT16.5X76

WT16.5X70.5

WT16.5X65

WT16.5X59

WT15X117.5

WT15X105.5

WT15X95.5

WT15X86.5

WT15X74

WT15X66

WT15X62

WT15X58

WT15X54

WT15X49.5

WT13.5X108.5

WT13.5X97

WT13.5X89

WT13.5X80.5

WT13.5X73

WT13.5X64.5

WT13.5X57

WT13.5X51

WT13.5X47

WT13.5X42

WT12X88

WT12X81

WT12X73

WT12X65.5

WT12X58.5

WT12X52

WT12X51.5

WT12X47

WT12X42

WT12X38

WT12X34

WT12X31

WT12X27.5

WT10.5X83

WT10.5X73.5

WT10.5X66

WT10.5X61

WT10.5X55.5

WT10.5X50.5

WT10.5X46.5

WT10.5X41.5

63

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CAESAR II Technical Reference Manual

WT10.5X36.5

WT10.5X34

WT10.5X31

WT10.5X28.5

WT10.5X25

WT10.5X22

WT9X71.5

WT9X65

WT9X59.5

WT9X53

WT9X48.5

WT9X43

WT9X38

WT9X35.5

WT9X32.5

WT9X30

WT9X27.5

WT9X25

WT9X23

WT9X20

WT9X17.5

WT8X50

WT8X44.5

WT8X38.5

WT8X33.5

WT8X28.5

WT8X25

WT8X22.5

WT8X20

WT8X18

WT8X15.5

WT8X13

WT7X365

WT7X332.5

WT7X302.5

WT7X275

WT7X250

WT7X227.5

WT7X213

WT7X199

WT7X185

WT7X171

WT7X155.

MT7X9

MT6X5.9

MT5X4.5

MT4X3.25

MT3X2.2

MT2.5X9.45

ST12X60.5

ST12X53

ST12X50

ST12X45

ST12X40

ST10X48

ST10X43

ST10X37.5

ST10X33

ST9X35

ST9X27.35

ST7.5X25

ST7.5X21.45

ST6X25

ST6X20.4

ST6X17.5

ST6X15.9

ST5X17.5

ST5X12.7

ST4X11.5

ST4X9.2

ST3.5X10

ST3.5X7.65

ST3X8.625

ST3X6.25

ST2.5X7.375

ST2.5X5

ST2X4.75

ST2X3.85

ST1.5X3.75

L9X4X0.6250

L9X4X0.5625

L9X4X0.5000

L8X8X1.1250

L8X8X1.0000

L8X8X0.8750

L8X8X0.7500

L8X8X0.6250

L8X8X0.5625

L8X8X0.5000

L8X6X1.0000

L8X6X0.8750

L8X6X0.7500

L8X6X0.6250

L8X6X0.5625

L8X6X0.5000

L8X6X0.4375

L8X4X1.0000

L8X4X0.7500

L8X4X0.5625

L8X4X0.5000

L7X4X0.7500

L7X4X0.6250

L7X4X0.5000

ST1.5X2.85

Chapter 4 Structural Steel Modeler

L7X4X0.3750

L6X6X1.0000

L6X6X0.8750

L6X6X0.7500

L6X6X0.6250

L6X6X0.5625

L6X6X0.5000

L6X6X0.4375

L6X6X0.3750

L6X6X0.3125

L6X4X0.8750

L6X4X0.7500

L6X4X0.6250

L6X4X0.5625

L6X4X0.5000

L6X4X0.4375

L6X4X0.3750

L6X4X0.3125

L6X3.5X0.5000

L6X3.5X0.3750

L6X3.5X0.3125

L5X5X0.8750

L5X5X0.7500

L5X5X0.6250

L5X5X0.5000

L5X5X0.4375

L5X5X0.3750

L5X5X0.3125

L5X3.5X0.7500

L5X3.5X0.6250

L5X3.5X0.5000

L5X3.5X0.4375

L5X3.5X0.3750

L5X3.5X0.3125

L5X3.5X0.2500

L5X3X0.6250

L5X3X0.5000

L5X3X0.4375

L5X3X0.3750

L5X3X0.3125

L5X3X0.2500

L4X4X0.7500

L4X4X0.6250

L4X4X0.5000

L4X4X0.4375

L4X4X0.3750

L4X4X0.3125

L4X4X0.2500

L4X3.5X0.5000

L4X3.5X0.4375

L4X3.5X0.3750

L4X3.5X0.3125

L4X3.5X0.2500

L4X3X0.5000

L4X3X0.4375

L4X3X0.3750

L4X3X0.3125

L4X3X0.2500

L3.5X3.5X0.5000

L3.5X3.5X0.4375

L3.5X3.5X0.3750

L3.5X3.5X0.3125

L3.5X3.5X0.2500

L3.5X3X0.5000

L3.5X3X0.4375

L3.5X3X0.3750

L3.5X3X0.3125

L3.5X3X0.2500

L3.5X2.5X0.5000

L3.5X2.5X0.4375

L3.5X2.5X0.3750

L3.5X2.5X0.3125

L3.5X2.5X0.2500

L3X3X0.5000

L3X3X0.4375

L3X3X0.3750

L3X3X0.3125

L3X3X0.2500

L3X3X0.1875

L3X2.5X0.5000

L3X2.5X0.4375

L3X2.5X0.3750

L3X2.5X0.3125

L3X2.5X0.2500

L3X2.5X0.1875

L3X2X0.5000

L3X2X0.4375

L3X2X0.3750

L3X2X0.3125

L3X2X0.2500

L3X2X0.1875

L2.5X2.5X0.5000

L2.5X2.5X0.3750

L2.5X2.5X0.3125

L2.5X2.5X0.2500

L2.5X2.5X0.1875

L2.5X2X0.3750

L2.5X2X0.3125

L2.5X2X0.2500

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CAESAR II Technical Reference Manual

L2.5X2X0.1875

L2X2X0.3750

L2X2X0.3125

L2X2X0.2500

L2X2X0.1875

L2X2X0.1250

D8X8X1.1250

D8X8X1.0000

D8X8X0.8750

D8X8X0.7500

D8X8X0.6250

D8X8X0.5000

D6X6X1.0000

D6X6X0.8750

D6X6X0.7500

D6X6X0.6250

D6X6X0.5000

D6X6X0.3750

D5X5X0.8750

D5X5X0.7500

D5X5X0.5000

D5X5X0.3750

D5X5X0.3125

D4X4X0.7500

D4X4X0.6250

D4X4X0.5000

D4X4X0.3750

D4X4X0.3125

D4X4X0.2500

D3.5X3.5X0.3750

D3.5X3.5X0.3125

D3.5X3.5X0.2500

D3X3X0.5000

D3X3X0.3750

D3X3X0.3125

D3X3X0.2500

D3X3X0.1875

D2.5X2.5X0.3750

D2.5X2.5X0.3125

D2.5X2.5X0.2500

D2.5X2.5X0.1875

D2X2X0.3750

D2X2X0.3125

D2X2X0.2500

D2X2X0.1875

D2X2X0.1250

D8X6X1.0000

D8X6X0.7500

D8X6X0.5000

D8X4X1.0000

D8X4X0.7500

D8X4X0.5000

D7X4X0.7500

D7X4X0.5000

D7X4X0.3750

D6X4X0.7500

D6X4X0.6250

D6X4X0.5000

D6X4X0.3750

D6X3.5X0.3750

D6X3.5X0.3125

D5X3.5X0.7500

D5X3.5X0.5000

D5X3.5X0.3750

D5X3.5X0.3125

D5X3X0.5000

D5X3X0.3750

D5X3X0.3125

D5X3X0.2500

D4X3.5X0.5000

D4X3.5X0.3750

D4X3.5X0.3125

D4X3.5X0.2500

D4X3X0.5000

D4X3X0.3750

D4X3X0.3125

D4X3X0.2500

D3.5X3X0.3750

D3.5X3X0.3125

D3.5X3X0.2500

D3.5X2.5X0.3750

D3.5X2.5X0.3125

D3.5X2.5X0.2500

D3X2.5X0.3750

D3X2.5X0.2500

D3X2.5X0.1875

D3X2X0.3750

D3X2X0.3125

D3X2X0.2500

D3X2X0.1875

D2.5X2X0.3750

D2.5X2X0.3125

D2.5X2X0.2500

D2.5X2X0.1875

Chapter 4 Structural Steel Modeler

B8X6X1.0000

B8X6X0.7500

B8X6X0.5000

B8X4X1.0000

B8X4X0.7500

B8X4X0.5000

B7X4X0.7500

B7X4X0.5000

B7X4X0.3750

B6X4X0.7500

B6X4X0.6250

B6X4X0.5000

B6X4X0.3750

B6X3.5X0.3750

B6X3.5X0.3125

B5X3.5X0.7500

B5X3.5X0.5000

B5X3.5X0.3750

B5X3.5X0.3125

B5X3X0.5000

B5X3X0.3750

B5X3X0.3125

B5X3X0.2500

B4X3.5X0.5000

B4X3.5X0.3750

B4X3.5X0.3125

B4X3.5X0.2500

B4X3X0.5000

B4X3X0.3750

B4X3X0.3125

B4X3X0.2500

B3.5X3X0.3750

B3.5X3X0.3125

B3.5X3X0.2500

B3.5X2.5X0.3750

B3.5X2.5X0.3125

B3.5X2.5X0.2500

B3X2.5X0.3750

B3X2.5X0.2500

B3X2.5X0.1875

B3X2X0.3750

B3X2X0.3125

B3X2X0.2500

B3X2X0.1875

B2.5X2X0.3750

B2.5X2X0.3125

B2.5X2X0.2500

B2.5X2X0.1875

67

68

CAESAR II Technical Reference Manual

German 1991 Database I80

I100

I120

I140

I160

I180

I200

I220

I240

I260

I280

I300

I320

I340

I360

I380

I400

I425

I450

I475

I500

I550

I600

IPE80

IPE100

IPE120

IPE140

IPE160

IPE180

IPE200

IPE220

IPE240

IPE270

IPE300

IPE330

IPE360

IPE400

IPE450

IPE500

IPE550

IPE600

IPEO180

IPEO200

IPEO220

IPEO240

IPEO270

IPEO300

IPEO330

IPEO360

IPEO400

IPEO450

IPEO500

IPEO550

IPEV400

IPEV450

IPEV500

IPEV550

IPEV600

IPBI-100

IPBI-120

IPBI-140

IPBI-160

IPBI-180

IPBI-200

IPBI-220

IPBI-240

IPBI-260

IPBI-280

IPBI-300

IPBI-320

IPBI-340

IPBI-360

IPBI-400

IPBI-450

IPBI-500

IPBI-550

IPBI-600

IPBI-650

IPBI-700

IPBI-800

IPBI-900

IPBI-1000

IPB-100

IPB-120

IPB-140

IPB-160

IPB-180

IPB-200

IPB-220

IPB-240

IPB-260

IPB-280

IPB-300

IPB-320

IPB-340

IPB-360

IPB-400

IPB-450

IPB-500

IPB-550

IPB-600

IPB-650

IPB-700

IPB-800

IPB-900

IPB-1000

U30X15

U30

U40X20

U40

U50X25

U50

U60

U65

U80

U100

U120

U140

U160

U180

U200

U220

U240

U260

U280

U300

U320

U350

U380

U400

IPEO600

Chapter 4 Structural Steel Modeler

T20

T25

T30

T35

T40

T45

T50

T60

T70

T80

T90

T100

T120

T140

1/2I140

1/2I160

1/2I180

1/2I200

1/2I220

1/2I240

1/2I260

1/2I280

1/2I300

1/2I320

1/2I340

1/2I360

1/2I380

1/2I400

1/2I425

1/2I450

1/2I475

1/2I500

1/2IPE140

1/2IPE160

1/2IPE180

1/2IPE200

1/2IPE220

1/2IPE240

1/2IPE270

1/2IPE300

1/2IPE330

1/2IPE360

1/2IPE400

1/2IPE450

1/2IPE500

1/2IPE550

1/2IPE600

1/2IPEO180

1/2IPEO200

1/2IPEO220

1/2IPEO240

1/2IPEO270

1/2IPEO300

1/2IPEO330

1/2IPEO360

1/2IPEO400

1/2IPEO450

1/2IPEO500

1/2IPEO550

1/2IPEV400

1/2IPEV450

1/2IPEV500

1/2IPEV550

1/2IPEV600

1/2IPB140

1/2IPB160

1/2IPB180

1/2IPB200

1/2IPB220

1/2IPB240

1/2IPB260

1/2IPB280

1/2IPB300

1/2IPB320

1/2IPB340

1/2IPB360

1/2IPB400

1/2IPB450

1/2IPB500

1/2IPB550

1/2IPB600

1/2IPB650

1/2IPB700

1/2IPB800

1/2IPB900

1/2IPB1000

1/2IPBI140

1/2IPBI160

1/2IPBI180

1/2IPBI200

1/2IPBI220

1/2IPBI240

1/2IPBI260

1/2IPBI280

1/2IPBI300

1/2IPBI320

1/2IPBI340

1/2IPBI360

1/2IPBI400

1/2IPBI450

1/2IPBI500

1/2IPBI550

1/2IPBI600

1/2IPBI650

1/2IPBI700

1/2IPBI800

1/2IPBI900

1/2IPBI1000

1/2IPBV140

1/2IPBV160

1/2IPBV180

1/2IPBV200

1/2IPBV220

1/2IPBV240

1/2IPBV260

1/2IPBV280

1/2IPBV300

1/2IPBV305

1/2IPBV320

1/2IPBV340

1/2IPBV360

1/2IPBV400

1/2IPBV450

1/2IPBV500

1/2IPBV550

1/2IPBV600

1/2IPBV650

1/2IPBV700

1/2IPBV800

1/2IPBV900

1/2IPBV1000

1/2IPEO600

69

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CAESAR II Technical Reference Manual

L20X3

L25X3

L25X4

L30X3

L30X4

L30X5

L35X4

L35X5

L40X4

L40X5

L45X4

L45X5

L50X5

L50X6

L50X7

Chapter 4 Structural Steel Modeler

Australian 1990 Database UB760X244

UB760X220

UB760X197

UB760X173

UB760X148

UB690X140

UB690X125

UB610X125

UB610X113

UB610X101

UB530X92

UB530X82

UB460X82

UB460X74

UB460X67

UB410X60

UB410X54

UB360X57

UB360X51

UB360X45

UB310X46

UB310X40

UB250X37

UB250X31

UB200X30

UB200X25

UB180X22

UB180X18

UB150X18

UB150X14

UC310X283

UC310X240

UC310X198

UC310X158

UC310X137

UC310X118

UC310X97

UC250X89

UC250X73

UC200X60

UC200X52

UC200X46

UC150X37

UC150X30

UC150X23

UC100X15

UBP310X79

UBP250X85

UBP250X63

TFB125X65

TFB100X45

TFC125X65

TFC100X50

TFC75X40

PFC380X100

PFC300X90

PFC250X90

PFC230X75

PFC150X75

EL200X200X26

EL200X200X20

EL200X200X18

EL200X200X16

EL200X200X13

EL150X150X19

EL150X150X16

EL150X150X12

EL150X150X10

EL125X125X16

EL125X125X12

EL125X125X10

EL125X125X8

EL100X100X12

EL100X100X10

EL100X100X8

EL100X100X6

EL90X90X10

EL90X90X8

EL90X90X6

EL75X75X10

EL75X75X8

EL75X75X6

EL75X75X5

EL65X65X10

EL65X65X8

EL65X65X6

EL65X65X5

EL55X55X6

EL55X55X5

EL50X50X8

EL50X50X6

EL50X50X5

PFC200X75

PFC180X75

71

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CAESAR II Technical Reference Manual

EL50X50X3

EL45X45X6

EL45X45X5

EL45X45X3

EL40X40X6

EL40X40X5

EL40X40X3

EL30X30X6

EL30X30X5

EL30X30X3

EL25X25X6

EL25X25X5

UL150X100X12

UL150X100X10

UL150X90X16

UL150X90X12

UL150X90X10

UL150X90X8

UL125X75X12

UL125X75X10

UL125X75X8

UL125X75X6

UL100X75X10

UL100X75X8

UL100X75X6

UL75X50X8

UL75X50X6

UL75X50X5

UL65X50X8

UL65X50X6

EL25X25X3

UL65X50X5

Chapter 4 Structural Steel Modeler

South African 1992 Database IPE100 IPE200 IPE-AA180 IP203X133X30 IP305X102X29 IP356X171X45 IP406X140X46 IP457X191X67 IP533X210X82 IP610X229X101 IP838X292X176

IPE120 IPE-AA100 IPE-AA200 IP254X146X31 IP305X102X33 IP356X171X51 IP406X178X54 IP457X191X75 IP533X210X93 IP610X229X113 IP914X305X201

IPE140 IPE-AA120 IP152X89X16 IP254X146X37 IP305X165X41 IP356X171X57 IP406X178X60 IP457X191X82 IP533X210X101 IP610X229X125 IP914X419X343

IPE160 IPE-AA140 IP178X102X19 IP254X146X43 IP305X165X46 IP356X171X67 IP406X178X67 IP457X191X90 IP533X210X109 IP610X229X140

IPE180 IPE-AA160 IP203X133X25 IP305X102X25 IP305X165X54 IP406X140X39 IP406X178X75 IP457X191X98 IP533X210X122 IP762X267X147

HP152X152X23 HP203X203X60 HP254X254X107 HP305X305X137

HP152X152X30 HP203X203X71 HP254X254X132 HP305X305X158

HP152X152X37 HP203X203X86 HP254X254X167 HP305X305X198

HP203X203X46 HP254X254X73 HP305X305X97 HP305X305X240

HP203X203X52 HP254X254X89 HP305X305X118 HP305X305X283

IT127X76X13 IT254X152X59

IT152X89X17 IT305X152X66

IT178X102X22

IT203X102X25

IT203X152X52

CP100X50 CP200X75 CP300X100

CP120X55 CP220X80

CP140X60 CP240X85

CP160X65 CP260X90

CP180X70 CP280X95

CT100X50X11 CT200X75X25 CT300X100X46 CT381X102X55

CT120X55X13 CT220X80X29 CT76X38X7

CT140X60X16 CT240X85X33 CT127X64X15

CT160X65X19 CT260X90X38 CT152X76X18

CT180X70X22 CT280X95X42 CT178X54X15

AE25X25X3 AE35X35X5 AE45X45X5 AE50X50X6 AE60X60X8 AE80X80X6 AE90X90X8 AE100X100X12 AE120X120X15 AE200X200X16

AE25X25X5 AE40X40X3 AE45X45X6 AE50X50X8 AE60X60X10 AE80X80X8 AE90X90X10 AE100X100X15 AE150X150X10 AE200X200X18

AE30X30X3 AE40X40X5 AE50X50X3 AE60X60X4 AE70X70X6 AE80X80X10 AE90X90X12 AE120X120X8 AE150X150X12 AE200X200X20

AE30X30X5 AE40X40X6 AE50X50X4 AE60X60X5 AE70X70X8 AE80X80X12 AE100X100X8 AE120X120X10 AE150X150X15 AE200X200X24

AE35X35X3 AE45X45X3 AE50X50X5 AE60X60X6 AE70X70X10 AE90X90X6 AE100X100X10 AE120X120X12 AE150X150X18

AU65X50X6 AU80X60X8 AU100X65X10 AU125X75X8 AU150X75X15

AU65X50X8 AU90X65X6 AU100X75X6 AU125X75X10 AU150X90X10

AU75X50X6 AU90X65X8 AU100X75X8 AU125X75X12 AU150X90X12

AU75X50X8 AU90X65X10 AU100X75X10 AU150X75X10 AU150X90X15

AU80X60X6 AU100X65X8 AU100X75X12 AU150X75X12

TCI203X133X25

TCI203X133X30

TCI254X146X31 TCI254X146X37

TCI254X146X43

73

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CAESAR II Technical Reference Manual

Korean 1990 Database W594X302

W588X300

W582X300

W612X202

W606X201

W600X200

W596X199

W488X300

W482X300

W506X201

W500X200

W496X199

W440X300

W434X299

W450X200

W446X199

W390X300

W386X299

W404X201

W400X200

W396X199

W350X350

W344X354

W344X348

W340X250

W336X249

W354X176

W350X175

W346X174

W310X310

W310X305

W304X301

W300X305

W300X300

W298X299

W294X302

W298X201

W294X200

W300X150

W298X149

W250X255

W250X250

W248X249

W244X252

W244X175

W250X125

W248X124

W208X202

W200X204

W200X200

W194X150

W200X100

W150X150

W148X100

W150X75

W125X125

W100X100

L250X250X35

L250X250X25

L200X200X25

L200X200X20

L200X200X15

L175X175X15

L175X175X12

L150X150X19

L150X150X15

L150X150X12

L150X150X10

L130X130X15

L130X130X12

L130X130X10

L130X130X9

L120X120X8

L100X100X13

L100X100X10

L100X100X8

L100X100X7

L90X90X13

L90X90X10

L90X90X9

L90X90X8

L90X90X7

L90X90X6

L80X80X7

L80X80X6

L75X75X12

L75X75X9

L75X75X6

L70X70X6

L65X65X8

L65X65X6

L65X65X5

L60X60X6

L60X60X5

L60X60X4

L50X50X6

L50X50X5

L50X50X4

L45X45X5

L45X45X4

L40X40X5

C300X90

C300X91

C300X92

C300X93

C125X65

C100X50

C75X40

M300X150

M250X125

M200X100

M150X75

M125X75

C300X94

Chapter 4 Structural Steel Modeler

UK 1993 Database

75

1

CHAPTER 5

Controlling the Dynamic Solution In This Chapter Dynamic Analysis Input ..............................................................2 Dynamic Analysis Overview .......................................................3 Harmonic Analysis ......................................................................8 Response Spectra / Time History Load Profiles..........................16 Building Spectrum / Time History Load Cases ...........................24 Spectrum Time History ...............................................................38 Lumped Masses...........................................................................44 Dynamic Control Parameters.......................................................48 Advanced Parameters ..................................................................81 Pulsation Loads ...........................................................................85 Relief Valve Thrust Load Analysis .............................................88

2

CAESAR II Technical Reference Manual

Dynamic Analysis Input Once the basic model has been constructed a dynamic analysis can be performed. After selecting ANALYSIS/ DYNAMICS from the CAESAR II Main Menu, the Dynamics Input window appears.

The analysis type is selected from the drop list on the upper left portion of the window and the tabbed items will be modified depending on the type of analysis to be performed. If the model contains spring hangers to be designed, or single directional supports, gaps, rods, or friction, then a static analysis must be performed before the dynamic analysis to determine how the nonlinear supports are acting. The following sections describe the specific input for each of the options available from the Dynamics Input Menu. See Chapter 8 of the User Guide for a thorough discussion of basic dynamic load cases and data, and for a description of “how to” interact with the dynamics input processor. The current units applicable to the dynamics input are pulled from the piping input file (or from the Configuration file in the event of a structural-only job).

Chapter 5 Controlling the Dynamic Solution

3

Dynamic Analysis Overview A piping system may respond far differently to a dynamic load than it would to a static load of the same magnitude. Static loads are those which are applied slowly enough that the system has time to react and internally distribute the loads, thus remaining in equilibrium. In equilibrium, all forces and moments are resolved (i.e., the sum of the forces and moments are zero), and the pipe does not move. With a dynamic load—a load which changes quickly with time—the piping system may not have time to internally distribute the loads, so forces and moments are not always resolved—resulting in unbalanced loads, and therefore pipe movement. Since the sum of forces and moments are not necessarily equal to zero, the internally induced loads can be different—either higher or lower—than the applied loads. For this reason, different analysis methods must be used to determine response of a system when subjected to dynamic loads. CAESAR II provides several methods for analyzing different types of dynamic loadings, which help optimize the trade-off of accuracy vs. computing requirements—these include harmonic solution, response spectrum method, and time history analysis. The force vs. time profiles of the dynamic loads most often encountered during the design of piping are usually one of three types—random, harmonic, or impulse. Each of these load profiles have a preferred solution method as well. These profiles, and the load types identified with them, are described below.

Random With this type of profile, the load changes direction and/or magnitude unpredictably with time, although there may be predominant characteristics within the load profile. Loads with random force/time profiles are best solved using the Spectrum method. Major types of loads with random time profiles are Wind—Wind velocity causes forces due to the decrease of wind momentum as the air strikes the pipe, creating an “equivalent pressure” on the pipe. Wind loadings, even though they may have predominant directions and average velocities over a given time, are subject to gusting, i.e., sudden changes in direction and velocity. As the observed time period lengthens, the observed number of changes increases in an unpredictable manner as well, eventually encompassing nearly all directions and a wide range of velocities. Earthquake—Seismic (earthquake) loadings are caused by the introduction of random motion (accelerations, velocities, and displacements) of the ground and corresponding inertia loads (the mass of the system times the acceleration) into a structure through the structure-to-ground anchorage. The random ground motion is actually the sum of an infinite number of individual harmonic (cyclic) ground motions. Two earthquakes may be similar in terms of predominant direction (along a fault, for example), predominant harmonic frequencies (if certain of the underlying cyclic motions tend to dominate), and maximum ground motion, but their exact behavior at any given time may be quite different and unpredictable.

Harmonic With this type of profile, the load changes direction and/or magnitude following a harmonic profile, ranging from its minimum to its maximum over a fixed time period. For example, the load may be described by a function of the form: F(t) = A + B cos( t + Q)

4

CAESAR II Technical Reference Manual

Where: F(t)

=

force magnitude as a function of time

A

=

mean force

B

=

variation of maximum and minimum force from mean

=

angular frequency (radian/sec)

Q

=

phase angle (radians)

t

=

time (sec)

Loads with harmonic force/time profiles are best solved using the Harmonic method. Major types of loads with harmonic time profiles are Equipment vibration—If rotating equipment attached to a pipe is slightly out of tolerance (drive shaft out of round, for example), it may impose a small cyclic displacement onto the pipe at the point of attachment, where the displacement cycle would most likely correspond to the equipment’s operating cycle. The displacement at the pipe connection may be so small as to not even be noticeable, but dynamically it could cause significant problems. The loading vs. time can be easily predicted once the equipment’s operating cycle and variation from tolerance is known. Acoustic vibration—If fluid flow characteristics are changed within a pipe (for example if flow conditions change from laminar to turbulent as the fluid goes through an orifice), slight lateral vibrations may be set up within the pipe. Often these vibrations fit harmonic patterns, with predominant frequencies somewhat predictable based upon the flow conditions. For example, Strouhal’s equation predicts that the developed frequency (Hz) of vibration caused by flow through an orifice will be somewhere between 0.2 V/D and 0.3 V/D, where V is the fluid velocity (ft./sec) and D is the diameter of the orifice (ft). Wind flow around a pipe sets up lateral displacements as well (a phenomenon known as vortex shedding), with an exciting frequency in the area of 0.18 V/D, where V is the wind velocity and D is the outer diameter of the pipe. Pulsation—During the operation of a reciprocating pump or a compressor, the fluid is compressed by pistons driven by a rotating shaft. This causes a cyclic change (vs. time) in the fluid pressure at any specified location in the system. If the fluid pressures at opposing elbow pairs or closures is unequal, this creates an unbalanced pressure load in the system. Since the pressure balance changes with the cycle of the compressor, the unbalanced force changes as well. (Note that the frequency of the force cycle will most likely be some multiple of that of the equipment operating cycle, since multiple pistons will cause a corresponding number of force variations during each shaft rotation.) The pressure variations will continue to move along through the fluid, so in a steady state flow condition, unbalanced forces may be present simultaneously at all elbow pairs in the system. The load magnitudes may vary, and the load cycles may or may not be in phase with each other, depending upon the pulse velocity, the distance of each elbow pair from the compressor, and the length of the piping legs between the elbow pairs. For example, if the pressure at elbow a is denoted by Pa(t) and the pressure at elbow b is denoted by Pb(t), then the unbalanced force acting along the pipe between the two elbows is: F(t) = (Pa(t) - Pb(t)) A Where: A

=

internal area of the pipe

The expression for Pa(t) can be calculated as (assuming that the pressure peak hits the elbow “a” at time t = 0): Pa(t)

=

Pavg + 0.5 (dP) cos

t

Chapter 5 Controlling the Dynamic Solution

5

Where: Pavg = dP

average pressure in the line =

alternating component of the pressure

=

driving angular frequency of pulse

If the length of the pipe between the elbows is L, then the pressure pulse will reach elbow b ts after it has passed elbow a: ts = L / c Where: c

=

speed of sound in the fluid

Therefore the expression for the pressure at elbow b is: Pb(t)

=

Pavg + 0.5(dP) cos (

t - Q)

Q

=

phase shift between the pressure peaks at a and b

Where:

=

ts

Combining these equations, the equation for the unbalanced pressure force acting on an elbow pair can be written as: F(t) = 0.5(dP)A * [ cos

t - cos

(t - L/c) ]

Under steady-state conditions, a similar situation would exist at all elbow pairs throughout the piping system.

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CAESAR II Technical Reference Manual

Impulse With this type of profile, the load magnitude ramps up from zero to some value, remains relatively constant for a time, and then ramps down to zero again. For rapid ramping times, this type of profile resembles a rectangle. Loads with impulse force/time profiles are best solved using the Time History or Force Spectrum methods. Major types of loads with impulse time profiles are Relief valve—When system pressure reaches a dangerous level, relief valves are set to open in order to vent fluid and reduce the internal pressure. Venting through the valve causes a jet force to act on the piping system; this force ramps up to its full value, from zero, over the opening time of the valve. The relief valve remains open (and the jet force remains relatively constant) until sufficient fluid is vented to relief the over-pressure situation. The valve then closes, ramping down the jet force over the closing time of the valve. Fluid hammer—When the flow of fluid through a system is suddenly halted at one point, through valve closure or a pump trip, the fluid in the remainder of the system cannot be stopped instantaneously as well. As fluid continues to flow into the area of stoppage (upstream of the valve or pump), the fluid compresses, causing a high pressure situation at that point. Likewise, on the other side of the restriction, the fluid moves away from the stoppage point, creating a low pressure (vacuum) situation at that location. Fluid at the next elbow or closure along the pipeline is still at the original operating pressure, resulting in an unbalanced pressure force acting on the valve seat or the elbow. The fluid continues to flow, compressing (or decompressing) fluid further away from the point of flow stoppage, thus causing the leading edge of the pressure pulse to move through the line. As the pulse moves past the first elbow, the pressure is now equalized at each end of the pipe run, leading to a balanced (i.e., zero) pressure load on the first pipe leg. However the unbalanced pressure, by passing the elbow, has now shifted to the second leg. The unbalanced pressure load will continue to rise and fall in sequential legs as the pressure pulse travels back to the source (or forward to the sink). The ramp up time of the profile roughly coincides with the elapsed time from full flow to low flow, such as the closing time of the valve or trip time of the pump. Since the leading edge of the pressure pulse is not expected to change as the pulse travels through the system, the ramp down time is the same. The duration of the load from initiation through the beginning of the down ramp is equal to the time required for the pressure pulse to travel the length of the pipe leg. Slug flow—Most piping systems are designed to handle single-phase fluids (i.e., those which are uniformly liquid or gas). Under certain circumstances, however, the fluid may have multiple phases. For example, slurry systems transport solid materials in liquids, and gases may condense, creating pockets of liquid in otherwise gaseous media. Systems carrying multi-phase fluids are susceptible to slug flow. In general, when fluid changes direction in a piping system, this is done through the application of forces at elbows. This force is equal to the change in momentum with respect to time, or Fr = dp / dt =

v2 A [2(1 - cos )]1/2

Where: dp

=

change in momentum

dt

=

change in time

=

fluid density

v

=

fluid velocity

A

=

internal area of pipe

Chapter 5 Controlling the Dynamic Solution

=

7

inclusion angle at elbow

Normally this force is constant, and is small enough that it can be easily absorbed through tension in the pipe wall, to be passed on to adjacent elbows which may have equal and opposite loads, zeroing the net load on the system. Therefore these type of momentum loads are usually ignored by the stress analyst. However, if the fluid velocity or density changes with time, this momentum load will change with time as well, leading to a dynamic (changing) load, which may not be cancelled by the load at other elbows. For example, consider a slug of liquid in a gas system. The steady state momentum load is insignificant, since the fluid density of a gas is effectively zero. Suddenly the liquid slug hits the elbow, increasing the momentum load by orders of magnitude. This load lasts only as long as it takes for the slug to traverse the elbow, and then suddenly drops to near zero again, with the exact profile of the slug load depending upon the shape of the slug. The time duration of the load depends upon the length of the slug divided by the velocity of the fluid.

Where: Fx = v2 A(1 - cos ) Fr = v2 A [2(1 - cos )]2 Fy = v2 A sin

8

CAESAR II Technical Reference Manual

Harmonic Analysis Excitation Frequencies

Harmonic Analysis Excitation Frequencies

Starting Frequency First frequency in the user’s defined excitation frequency range. The defined harmonic displacements and forces will have the form: A*cosine(wt+p), where A is the amplitude of the force or displacement, p is the phase angle, and is the frequency of the loading. Real and imaginary solutions will be developed for each frequency in the defined range (from which any phased solution can be calculated). For an entered frequency range to be valid there must be at least a starting frequency. All frequencies are entered in Hertz.

Ending Frequency Last frequency in the user’s defined excitation frequency range. If omitted then it defaults to the Starting frequency.

Chapter 5 Controlling the Dynamic Solution

Increment Frequency increment. If omitted then defaults to 1.0 Hz. The frequencies for harmonic excitation are taken from each frequency range defined by the user. Individual frequencies for excitation are computed using a “DO LOOP” type of logic as follows: X = STARTING FREQUENCY 5

CONTINUE COMPUTE SOLUTION FOR FREQUENCY “X” X = X + INCREMENT IF( X .LT. ENDING FREQUENCY+0.001) GO TO 5

9

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CAESAR II Technical Reference Manual

Using this logic the user can determine exactly which frequencies in a specified frequency range will be analyzed. The sign of the frequency increment may be modified by CAESAR II to properly step from the user’s starting frequency to his ending frequency. Either the starting frequency, the ending frequency, or the frequency increment may be given as a fraction or a whole part with fraction. Any number of user comment lines may be included. There can be any number of line entries in the Excitation frequency data. EXAMPLES: Find harmonic solutions for the following group of equipment speeds: 100 rpm (Warm up speed) 400, 800, 1200, 1600, 2000, 2400, 2800, 3200 rpm. Speeds passed through very slowly while coming up to operating speed. 3600 rpm. Operating speed. Rotations per minute convert to cycles per second by dividing by 60. Frequency excitation would be input. WARM UP SPEED (DIVIDE RPM BY 60 TO GET HERTZ) 100/60 BRINGING TURBINE ON-LINE (DIVIDE RPM BY 60 TO GET HERTZ) 400/60 3200/60 400/60 OPERATING SPEED (DIVIDE RPM BY 60 TO GET HERTZ) 3600/60 A low frequency field vibration exists in the piping system at about 3 Hertz. Define a 3 Hertz excitation: APPROXIMATE FIELD OBSERVED EXCITATION FREQUENCY (HZ) 3

The response of the piping system when the dynamic load was applied at 3 Hertz was almost zero. This was true regardless of the magnitude of the dynamic load (i.e. the maximum conceivable varying pressure load was applied, and there were still no appreciable dynamic displacements when the excitation frequency was 3 Hertz). Apply the dynamic load over a range of frequencies around 3 Hertz and see if any dynamic response can be observed. GROUP OF FREQUENCIES AROUND THE FIELD “GUESSED AT” 3 HERTZ EXCITATION. THE EXCITATION FREQUENCIES DEFINED BY THE INPUT BELOW ARE: (2.5, 2.6, 2.7, ..., 3.3, 3.4, 3.5) HZ. 2.5 3.5 0.1

Load Cycles Number of cycles expected for this loading. If entered, this signals to CAESAR II that the harmonic load case should be treated as a fatigue stress case with the allowable stress based on the number of anticipated cycles.

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Harmonic Forces and Displacements

Harmonic Forces

Either the Harmonic Forces or the Displacements must be entered in addition to the Excitation Frequency Data. Click the Harmonic Forces button to bring up a window like that shown below. Click the + button on the toolbar to add a harmonic force.

Force Amplitude of the harmonic force. The form of the harmonic forcing function is: F(t) = A*cosine( t- ), where “F(t)” is the force as a function of time. “A” is the maximum amplitude of the dynamic force. “ ” is the frequency of the excitation (in radians per second), and “p” is the phase angle (in radians). Enter the force in the units shown. These units are taken from the current set which resides on the file UNITS.FIL.

Direction Enter the line of action of the force as either X, Y, Z, or as direction cosines or direction vectors. The format for direction cosines is (cx,cy,cz), i.e (0.707,0.0,0.707). The format for direction vectors is (vx, vy, vz), i.e. (1,0,1).

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CAESAR II Technical Reference Manual

Phase Enter the phase angle in degrees. The harmonic loading can start with its maximum load at time equal to zero, or the harmonic load can start with its maximum at any time between zero and t=2*pi/w seconds. The phase angle is the method used to specify this time shift in the dynamic load waveform. The phase angle can be calculated from the time shift using the equation: p(degrees) = 180tw/pi, where t is given in seconds and w is given in radians per second. Most frequently the phase angle is entered as either zero or 90. The phase specification is most useful when defining eccentric loads on rotating equipment. Some of the examples that follow discuss common applications of the phase angle input. The phase angle is a required input. If the phase angle is zero, then 0.0 must be entered !

Start Node The node where the force is to act. This entry is required. If entered without a Stop Node and Increment, then this node must exist in the piping system. If entered with a Stop Node and Increment, then the range of nodes identified by the loop must include at least one node in the piping system.

Stop Node Used as a part of a “range of nodes” force loading command. This entry is optional.

Increment Used as a part of a “range of nodes” force loading command. This entry is optional.

EXAMPLES It is assumed that a pressure pulse traveling in the line between nodes 95 and 100 causes the line to shake at about 2 hertz. The magnitude of the pressure loading (See the examples for calculating forces from pressures) is estimated to be about 460 lb. The pressure wave travels from 95 to 100. The harmonic force to model this load is shown as follows. Note that the magnitude is divided by 2 because the total variation in the dynamic load is a function of the cosine, which varies from -1 to 1. To find the true response magnitudes from a positive only harmonic load pulse, a static solution with 460/2 lb. acting in the plus X direction would have to be superimposed on the static 460/2 lb. solution to provide the constant shifting of the load axis (i.e. as defined in the following example, there will exist a negative load at node 95 due to the negative sign on the cosine). The pressure pulse will always be positive and so a negative load will never exist. The superposition of the 460/2 static solution makes sure that the dynamic load (and probably the resulting displacements) are always positive. 460 LB PRESSURE LOAD AT 2 HERTZ

460/2 X 0.0 95

A pump is shaking in the X-Y plane. The pump axis is along the global Z axis. The magnitude of the dynamic load is computed to be 750 lb. from the manufacturers provided masses and eccentricities. Apply this rotating equipment loading on the inline pump at node 350. The X and Y loads are 90 degrees out of phase with one another. When the X load is at its maximum the Y load is zero, and when the Y load is at its maximum the X load is zero. ESTIMATED ECCENTRIC LOAD ON INLINE PUMP DOH-V33203001 750 X 0.0 350 750 Y 90.0 350

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Harmonic Displacements

Displacement Amplitude of the harmonic displacement. The form of the harmonic displacement function is: D(t)=(A)*cosine( t- ), where “D(t)” is the displacement as a function of time, A is the maximum amplitude of the dynamic displacement. “ ” is the frequency of the excitation (in radians per second), and “ ” is the phase angle (in radians). Enter the displacements in the units shown.

Direction Enter the line of action of the displacement as either X, Y, Z, or as direction cosines or direction vectors. The format for direction cosines is (cx,cy,cz), i.e (0.707,0.0,0.707). The format for direction vectors is (vx, vy, vz), i.e. (1,0,1).

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CAESAR II Technical Reference Manual

Phase Enter the phase angle in degrees. The harmonic displacements can start with its maximum displacement at time equal to zero, or the harmonic displacements can start with its maximum displacements at any time between zero and t + 2 / seconds. The phase angle is the method used to specify this time shift in the dynamic load waveform. The phase angle can be calculated from the time shift using the equation: (degrees) = 180t / , where t is given in seconds and is given in radians per second. Most frequently the phase angle is entered as either zero or 90. The phase specification is most useful when defining eccentric displacements on rotating equipment. Some of the examples that follow discuss common applications of the phase angle input. The phase angle is a required input. If the phase angle is zero, then 0.0 must be entered!

Start Node Node where the dynamic displacement is defined. If the node is a supported node, then the dynamic displacement will be assumed to act at the support point. If the node is not supported, then the dynamic displacement will be assumed to describe the exact motion of the pipe at that point. This differentiation only becomes important when the node is supported by a flexible restraint. For example, node 55 is supported in the Y direction by a restraint having a stiffness of 5000 lb./in. A harmonic displacement is also specified at node 55, in the Y direction. In this case, the harmonic displacement does not describe the displacement that is attached to 55!

Harmonic Displacements at Compressor Flange 0.008

Y

0.0

330

0.003

Z

0.0

330

If the Start Node is entered without a Stop Node and Increment, then this node must exist in the piping system. If the Start Node is entered with a Stop Node and Increment, then this range of nodes must include at least one node in the piping system.

Stop Node Used as a part of a “range of nodes” force displacement loading. This entry is optional.

Increment Used as a part of a “range of nodes” force displacement loading. This entry is optional. EXAMPLES A large ethylene compressor shakes the node exiting the compressor flange in the Y direction a field measured 8 mils, and in the Z direction an amount equal to 3 mils. Define these dynamic displacements. The displacements are assumed to be simultaneous, with no phase shift. This is because the load causing the displacements is believed to be the compressor plunger moving in the X, or axial direction. (The displacements are skewed because the piping configuration entering the compressor is itself skewed.)

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Applying estimated eccentric forces to the pump described in the harmonic force example did not produce the displacements witnessed in the field. Field personnel have measured the dynamic displacements in the vertical (Y) and transverse (Z) directions at the pump piping connections. The centerline of the pump, at the intersection of the horizontal suction and vertical discharge is node 15. The magnitude of the Z displacement was measured to be 12 mil. The magnitude of the Y displacement was measured to be 3 mils. It is assumed that the vibration is due to the rotation of the pump shaft, and so the Z and Y loads will be taken to be 90 degrees out of phase. HARMONIC DISPLACEMENTS MODELING PUMP VIBRATION ON THE INLINE PUMP DOH-V33203001. MODELLING THE PUMPS DYNAMIC LOAD WITH FORCES DID NOT RESULT IN THE DISPLACEMENTS WITNESSED BY FIELD PERSONNEL. NOW TRY IMPOSING THE DISPLACEMENTS AND SEE WHAT THE RESULTING FORCES ARE. ALSO CHECK TO SEE IF THE ATTACHED PIPING MOVES AROUND AS EXPECTED. Z MAGNITUDE OF THE LOAD - ZERO PHASE SHIFT 0.012 Z 0.0 15 Y MAGNITUDE OF THE LOAD - 90 DEG. PHASE SHIFT 0.003 Y 90.0 15

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CAESAR II Technical Reference Manual

Response Spectra / Time History Load Profiles

Spectrum Definitions

Name Can be any 24-character identifier. This name is associated with a particular spectrum or load profile. The complete definition of a shock includes its name, range type, ordinate type, range interpolation method, ordinate interpolation method, and the shock data point table. Everything but the shock data point table can be entered here. There are 14 predefined spectra for which no extra definitions are required and they are: El Centro For the El Centro California N-S component taken from Biggs, “Introduction to Structural Dynamics,” and applies for systems with 5-10 percent critical damping. REG. GUIDE 1.60 1.60H.5

and

1.60V.5

1.60H2

and

1.60V2

1.60H5

and

1.60V5

1.60H7

and

1.60V7

1.60H1.0

and

1.60V10

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Each of these spectra define respectively the horizontal and vertical components for 0.5, 2, 5, 7, and 10 percent critically damped systems. Associated with each of these spectra is a value for the Maximum ground acceleration at the site, the ZPA. (Zero Period Acceleration) This value defaults to 0.5 g and can be changed on the control parameter spreadsheet. Uniform Building Code UBCSOIL1 UBCSOIL2 UBCSOIL3 These spectra represent the normalized (horizontal) response spectra for three soil types provided in Figure 23-3 of the Uniform Building Code, (1991 Edition). Note The spectrum name (or load profile) can be preceded by a (#) sign. The (#) sign instructs CAESAR II to read the spectrum table from a file having the same name as the spectrum with no extension. Entering the spectrum table in an ASCII file allows several jobs to access the same spectrum table data without the user having to retype it for each job. If data is to be read directly from within the Dynamic Output then click the Data Points button and enter the appropriate Range and Ordinate values.

Range Type This entry defines the table “range”, or horizontal axis, and can be either “Period”, “Frequency”, or "Time". If the range type is Period then the spectrum table data must be entered in seconds. If the range type is Frequency then the spectrum table data must be entered in Hertz, (cycles per second). Time may be used for Time History load profiles only, and must be entered in milliseconds (ms).

Ordinate Type This entry defines the spectrum table “ordinate”, or vertical axis, and can be either Acceleration, Velocity, Displacement or Force (multiplier). Any part of the word for the ordinate type can be spelled out, but only the first letter is required. Note that acceleration units are length per second squared. Users may enter the spectrum table in g’s by selecting acceleration as the ordinate type and then using a shock scale factor of 386., for length units of inches. For Time History load profiles, the only valid ordinate type is Force (multiplier).

Range Interpolation Interpolation between range values may be done logarithmically or linearly (valid input is LOG or LIN). See the examples shown for additional discussion.

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CAESAR II Technical Reference Manual

Ordinate Interpolation Interpolation between ordinate values may be done logarithmically or linearly (valid input is LOG or LIN). See the examples shown for additional discussion. One job may have any number of different spectrum types and definitions. Special FORCE spectrum data files are created by the DLF Spectrum generator. See the documentation covering this item later in this chapter. When a new job is started up the 14 predefined spectra are already included in the spectrum definition list. Any combination of these predefined spectra may be used as is, deleted or used with any other user defined spectra. ASCII files that contain spectrum table data can contain comment lines starting with an asterisk just like regular terminal entered data lines. The user is encouraged to include the basic spectrum data definitions in the comments for each ASCII spectrum file. See the example that follows.

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EXAMPLE The job requires that the El Centro shock be applied in the X and Z directions using a factor of 1.0, and in the Y direction using a factor of 0.667. There is no spectrum definition required for this shock. El Centro is a predefined spectrum. All of its shock data resides in the CAESAR II shock database. The job requires the use of the Nuclear Regulatory Guide 1.60 shock loads. At a maximum acceleration value of 0.25 g’s, analysis is to be performed using 1.0 times the horizontal and vertical components of the shock as specified in Reg. Guide 1.60. There is no spectrum definition required for either of these two shock loads. The Reg. Guide 1.60 shock spectra are predefined. The user must only specify the maximum acceleration (ZPA) of 0.25 g’s on the control parameter spreadsheet, and must use the reg. guide spectra which corresponds to the anticipated system damping. Lower damping values mean more conservative results. The job requires a shock spectrum that is given by the client and developed for the site. A plot of the spectrum appears as follows. The horizontal axis is period and the vertical axis is acceleration. From the variation of the numbers along each axis it can be seen that a logarithmic interpolation for each axis should be used. Because the shock name is NOT preceded by a (#) sign the user will have to enter the points for this spectrum during this interactive input session. BENCHNO4 PERIOD ACCELERATION LOG LOG All jobs on a particular project require the use of the spectrum table shown as follows. Since we only want to type the spectrum’s data points in one time, the points will be entered into a file named “BENCH1”. The ASCII file BENCH1 can be created using any standard editor or the CAESAR II text editor. The listing of the ASCII file for BENCH1 is shown following the plot of the spectrum. The spectrum definition input for pointing to this file is: #BENCH1 PERIOD ACCEL LOG LOG

Listing of ASCII file “BENCH1”: SPECTRUM FOR NUCLEAR BENCHMARK NO.1. THIS SPECTRUM IS TO BE USED FOR ALL LINES ON PROJECT 1-130023-A03. FILENAME = “BENCH1” RANGE TYPE = PERIOD (SECONDS) ORDINATE TYPE = ACCELERATION (IN./SEC./SEC.) INTERPOLATION FOR BOTH AXES = LOGARITHMIC. FILE PREPARED BY M.NASH JANUARY 15, 1987 PERIOD(SEC)ACCELERATION(IN/SEC/SEC) 0.1698E-02

0.1450E+03

0.2800E-01

0.3800E+03

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CAESAR II Technical Reference Manual

0.5800E-01

0.7750E+03

0.7100E-01

0.7750E+03

0.9100E-01

0.4400E+03

0.1140E+00

0.1188E+04

0.1410E+00

0.1188E+04

0.1720E+00

0.7000E+03

0.2000E+00

0.8710E+03

0.2500E+00

0.8710E+03

0.3230E+00

0.4000E+03

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Response Spectrum / Time History Profile Data Point Input

Data points for user-defined spectra may be entered through the menu option Tools /Spectrum Data Points.

Range Spectrum table range value. There should be at least one range-ordinate pair for each spectrum.

Ordinate Spectrum table ordinate value. There should be at least one range ordinate pair for each spectrum. Values may be entered in exponential format (i.e. 0.3003E+03, or 0.3423E-03, or 0.3003E3,...), or can have explicit multiplication or division (i.e. 4032.3/386, or 1.0323*12). Sufficient data points should be entered to fully describe the spectrum or load profile. There can be any number of line entries in the spectrum data. Data may also be read from a file using the Read From File button.

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CAESAR II Technical Reference Manual

Force Response Spectrum Definitions The CAESAR II DLF Spectrum Generator takes the time waveform of some excitation and converts it into a frequency domain dynamic load factor (DLF) curve. The frequency domain dynamic load factor curve is written to a hard disk file and can be read directly by CAESAR II as a “FORCE” response spectrum curve. Input for the Pulse Table Generator is shown as follows.

DLF/Spectrum Table Generator

Force Spectrum Name The force spectrum generator creates an ASCII file containing the force spectrum that corresponds to the input time history waveform.

Maximum Table Frequency Enter the maximum frequency that should exist in the CAESAR II generated spectrum table. This value seldom needs to be greater than 100 HZ. If piping frequencies greater than 100 Hz are found in the system and included in the spectrum analysis, then the spectrum value at 100 Hz would be used. The user can decide which frequencies are important, and therefore how high the frequency must go, by looking at the solution participation factors and the animated mode shapes. Typically only the lower frequencies contribute to the system displacements, forces and stresses.

Number of Points in the Table This is the number of points CAESAR II will generate for the spectrum table. Usually 15 to 20 points are sufficient. These points are distributed in a cubic relationship starting from zero hertz.

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Create Table When the Create Table button is clicked, a dialog box will appear with the input table as displayed below. Enter the Time / Force data and click the OK button to create the DLF curve on the hard drive.

Input Table Dialog

Time Enter the points that describe the time waveform to be modeled. Units for this table are milliseconds. (1000 milliseconds equals one second.)

Force Enter the forces that correspond to the points on the force/time curve. Units are as shown. Note that the absolute magnitude of the force is not important, only the form of the time history loading is important. The actual maximum value of the dynamic load is taken from the force pattern defined in: SPECTRUM/TIME HISTORY FORCE SETS. There can be any number of line entries in the Excitation frequency data.

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CAESAR II Technical Reference Manual

Building Spectrum / Time History Load Cases

Time History Load Cases

Spectrum /Time History Profile Enter the name of the shock that was defined during the Time History Definitions phase of the input. This may be any type of spectra, user defined, predefined, or read from a file. (DO NOT PRECEDE THE SPECTRUM NAME WITH A # HERE, EVEN IF THE SPECTRUM TABLE WAS READ FROM AN ASCII DATA FILE!) Any number of shocks can be listed here. Individual contributions can be of any shock type or definition.

Factor Constant by which to multiply the shock table. Usually 1.0, or if the spectrum table data points were read in units of g’s, to convert to in/sec/sec then this factor would be 386. There are several examples that follow which illustrate various applications of this value.

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Direction Defines the direction of application of the shock. To define an earthquake type of loading, CAESAR II must know what the earthquake shock “looks like,” which comes from the shock spectrum table. CAESAR II must also know in which direction this shock acts. Typically a shock load case will be comprised of three shock components. One acts in the X direction, one in the Z, and one in the Y. The combination of each of these three “shocks” defines the earthquakes dynamic loading of the piping system. Skewed directions may be entered by giving a direction cosine or direction vector. Skewed shock contributions are entered when the piping or structural system appears particularly sensitive to a shock along a skewed line. This most often occurs when a majority of the piping system lies along a 45 degree line in the horizontal plane. An example shock input for this type of system is shown among the examples on the following pages. Any number of shock components can act in the same direction. i.e. there can be two X direction components. This usually occurs with independent support shock contributions where one X direction component would apply to one support group and another X direction component would apply to a different support group. (However, there can be two shock components in the same direction without having independent support contributions defined. This would just involve defining two shock contributions in the same direction without start, stop, or increment node entries.) In the simplest form of force spectrum loading there is only a single shock component in the load case, i.e. there is only a single line of input on the load case screen. When there are multiple lines of input on the load case screen, as when the user is analyzing a traveling pressure wave that impacts different elbowelbow pairs, there can be many components to the shock load case. The combination of responses from each of these shock loading components can be established in one of two ways. If the Direction field is the same for each load component, then the Directional Combination method will be used to combine the responses from each load component. If the Direction field is different for each load component, then the spatial combination method will be used to combine the responses from each load component. The difference between Spatial and Directional combination methods is that Directional combinations are always made before Modal combinations, while Spatial combinations can be made before or after Modal combinations, (it is user controlled). The default is to perform the Modal combinations before Spatial combinations. Either Spatial or Directional combinations can be made using the ABS or SRSS method. Some of the following force spectrum examples illustrate these differences. Note: Since Time History combinations are all algebraic (in-phase), this entry is used as nothing more than a label during this type of analysis.

Force Set # If the Spectrum/Load Profile Name describes a Force-type spectrum (rather than displacement, velocity, or acceleration), then the fourth entry in the load case screen is the force set number. This force set number corresponds to the loads entered in the Force Sets option. Examples shown on the following pages illustrate this application. Note that if a force set # is entered, the last three fields must be left blank!

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CAESAR II Technical Reference Manual

Start Node Start node, stop node, and increment are only used to define the component of an independent support shock (ISM). This is a shock component that applies only to a group of support points. For example, different shock spectrum may have been generated for rack level piping and for ground level piping. In this case the rack supports would be subject to one shock excitation (influenced by the rack’s response to the earthquake), and the ground level supports would be subject to a different shock excitation (not influenced by the rack). In this case, one node range would be used to define the rack support shock contributions and another would be used to define the ground support shock contributions. The range of nodes defined by the start node, stop node, and increment must include at least one support point.

Stop Node Part of the “range of nodes.” If omitted, defaults to the start node. See the examples that follow for clarification.

Increment Part of the “range of nodes.” If omitted, defaults to 1. See the examples that follows for clarification.

Anchor Movement (Earthquake Only) This entry is only used for independent support movements. It is used to specify the absolute displacement of the restraints included in this shock case. This displacement is used to calculate the pseudostatic load components representing the relative displacement of the individual restraint sets. If omitted, the default is taken from the lowest frequency entry of the response spectrum:specified displacement, velocity/frequency, or acceleration/frequency2 (where frequency is angular frequency).

Directives A number of directives can be set for each individual load case using the Directives button. These parameters are optional extensions to global options set for all load cases on the control parameter spreadsheet. Typically the user will not need to specify any of these options.

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Directional Combination Method. Similar directional components will be combined using either the ABS or the SRSS summation method. If there are two shock components in the X direction, the components from each shock’s effect on the system will be summed absolutely. Directional combinations are performed before all other combinations. (There are three types of combinations: DIRECTIONAL, SPATIAL AND MODAL). The default DIRECTIONAL combination method is ABS. Modal Combination Method. Modal (Group) Modal components will be combined using the Reg. Guide 1.92 “GROUPING” method. CAESAR II uses the Revision 1, February 1976 issue of the Regulatory Guide 1.92. See the discussion of the SPATIAL(ABS) directive for a description of the relationship that exits between modal and spatial response combinations. Modal (10%) Modal components will be combined using the Reg. Guide 1.92 “10%” method. Modal (DSRSS) Modal components will be combined using the Reg. Guide 1.92 “Double Square Root of the Sum of the Squares” method. Damping is assumed to be equal for all modes and is taken from the control parameter spreadsheet. Modal (ABS) Modal components (response quantities) will be combined absolutely. (i.e. the absolute value of each response quantity will be summed.) Modal (SRSS) Modal components will be combined using the square root of the sum of the squares method of combination. Spatial Combination Method (ABS or SRSS). Spatial components will be combined using the ABS summation method. There are typically three spatial components in a single earthquake type shock load case. The three usual excitation directions are the X, Y, and Z global axes. (Although there can be any number of spatial components along any global or skewed axes.) Spatial or Modal Combination First. Modal before Spatial summations are “Independent.” An Independent shock is one where the X, Y, Z components are random and temporally independent of one another. (i.e. time histories for each directional component of the shock are not equal.) Spatial before Modal summations are “Simultaneous.” A simultaneous shock is one where the X, Y, and Z components are random, but temporarily the same (i.e. time histories for each directional component of the shock are equal). Pseudostatic Combination Method (ABS or SRSS). Pseudostatic components for each ISM are added into the response quantities either absolutely or using the SRSS method of combination. Pseudostatic combinations are performed after all spatial and modal combinations. The user can deactivate the inclusion of pseudostatic component from the control parameter spreadsheet. Missing Mass Combination Method (ABS or SRSS). Missing mass components for each shock load are added into the response quantities either absolutely or using the SRSS method of combination. The user can deactivate the inclusion of missing mass components from the control parameter spreadsheet. Missing mass components are added in following modal summation. Stress Type (EXP). Stress type for the load case is set using the stress type drop list. If FATigue is selected, the expected number of load cycles must be entered. The user can change the default stress type dynamic loads to any of the allowed stress types in CAESAR II. Available stress types are EXP, SUS, OCC, OPE, and FAT. The OCC or occasional stress type is the default.

28

CAESAR II Technical Reference Manual The entry of node groups causes a pseudostatic component of the shock to be created. This pseudostatic contribution can be added or omitted from the final shock loading effects. Additional parameters can be entered on the control parameter spreadsheet. The order of input of the shock contributions is not important, and has no bearing on the results. There is no limit to the number of shock load cases the user can define. The dynamic output processor lets the user decide which of the Spectrum/Time History Load Cases he wants to process. Any number of user comment lines may be included. There can be any number of line entries in the spectrum data. EXAMPLES Define a shock load case that excites the piping system with a vibration of one times the El Centro earthquake in the X direction, one times the El Centro earthquake in the Z, and 0.667 times the El Centro earthquake in the Y direction. ELCENTRO

1

X

ELCENTRO

1

Z

ELCENTRO

0.667

Y

Define a shock load case that excites the piping system with the horizontal and vertical components of the Reg. Guide 1.60 shock spectra for a 2 percent critically damped system. The maximum ground acceleration should be 0.22 g’s. The maximum ground acceleration is set on the control parameter spreadsheet and has no effect on the shock load case definitions. 1.60H2 1

X

1.60H2 1

Z

1.60V2 1

Y

Define a shock load case that is comprised of the users shocks BENCH1 and BENCH2. BENCH1 should act in the X and Z directions, and shock BENCH2 should act in the Y direction. The scale factor for all shocks is 1.0. BENCH1

1

X

BENCH2

1

Y

BENCH1

1

Z

One of the shock load cases for this particular job should excite the piping system along a line that is 45 degrees off of the global axes in the horizontal plane. It is suspected that this direction of excitation will yield the worst possible results. Apply the user defined shock BENCH1 in the horizontal direction and BENCH2 in the vertical direction. BENCH1

1

(1,0,1)

BENCH1

1

(-1,0,1)

BENCH2

1

Y

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Define a shock load case that excites the piping system with a vibration of two times the El Centro earthquake in the X, Y, and Z directions. There should be two shock load cases in this job. The first should use an independent summation and the second a simultaneous. The load cases would be defined as shown. (There are several ways to accomplish the same objective here using parameters on the control parameter spreadsheet, etc. Only the method using the explicit definition of the load case combination method will be presented.) Remember that independent summation means MODAL then SPATIAL, and simultaneous means SPATIAL then MODAL. LOAD CASE 1 SHOCK CONTRIBUTIONS - CAESAR II’s title MODAL(GROUP), SPATIAL(SRSS), MODAL COMBINATIONS FIRST ELCENTRO

2

X

ELCENTRO

2

Y

ELCENTRO

2

Z

LOAD CASE 2 SHOCK CONTRIBUTIONS - CAESAR II’s title SPATIAL(SRSS), MODAL(GROUP), SPATIAL COMBINATIONS FIRST ELCENTRO

2

X

ELCENTRO

2

Y

ELCENTRO

2

Z

Define a shock case that has the user defined spectrum “1DIR” acting in the Z direction only. Set the stress type for the case to be operating and use modal summations before spatial summations. Note that there is no mention of modal or spatial summations in the load data shown as follows (only the stress type). This is because “modal summation first” is the CAESAR II default and would have to be changed on the control parameter spreadsheet for it not to still apply. 1DIR

1

Z

STRESSTYPE(OPE) The support nodes 5, 25, 35, 45, and 56 are pipe shoes sitting on concrete foundations. The support nodes 140, 145, 157, 160, and 180 are second level rack supports, i.e. pipe shoes sitting on structural steel beams in the second level of the rack. The ground level shock spectrum name is “GROUND04”, and the second level rack spectrum name is “RACKLEVEL2-04”. Set up the shock load case to define these independent support excitations. Note that an option exists on the control parameter spreadsheet to neglect the pseudostatic component of the Independent Support Excitation. Assume that this option is activated. The default is to include the pseudostatic component in an absolute (ABS) summation method. GROUND LEVEL EXCITATION GROUND04 1.0

X

5,56,1

GROUND04 1.0

Y

5,56,1

GROUND04 1.0

Z

5,56,1

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RACK LEVEL 2 EXCITATION RACKLEVEL2-04

1.0

X

140,180,1

RACKLEVEL2-04

1.0

Y

140,180,1

RACKLEVEL2-04

1.0

Z

140,180,1

Set up a shock load case, and define all combinations options explicitly. Use the same shock components as defined in the above example, except assume that the pseudostatic component is to be added using the SRSS combination method. Also change the modal summation method is SRSS. (This is the recommended method.) Note that when the modal summation method is SRSS it doesn't matter whether modal or spatial combinations are performed first. The order is only a factor when closely spaced modes are considered as in the grouping, ten percent, and DSRSS methods. MODAL(SRSS),PSEUDOSTATIC(SRSS),SPATIAL(SRSS) GROUND LEVEL EXCITATION GROUND04 1.0

X

5,56,1

GROUND04 1.0

Y

5,56,1

GROUND04 1.0

Z

5,56,1

RACK LEVEL 2 EXCITATION RACKLEVEL2-04

1.0

X

140,180,1

RACKLEVEL2-04

1.0

Y

140,180,1

RACKLEVEL2-04

1.0

Y

140,180,1

Chapter 5 Controlling the Dynamic Solution

31

The last elbow in the relief valve piping is at node 295. The spectrum name: “BLAST” contains the DLF response spectrum for this relief valve’s firing. SPECTRUM/TIME HISTORY FORCE SET #1 contains the load information and its point of application. Show the load case input that would provide the most conservative combination of modal results. (Because there is only a single loading there is no consideration given to spatial or directional combinations.) Shock Name, Factor, Direction, Force Set # ABSOLUTE MODAL SUMMATION, ONLY A SINGLE LOADING COMPONENT AND SO NO CONSIDERATION GIVEN TO SPATIAL OR DIRECTIONAL COMBINATIONS. BLAST, 1, X, 1 MODAL (ABS) Use the same example above and combine the modes using the grouping method. This will produce the most realistic solution. BLAST, 1, X, 1 MODAL (GROUP) There are two elbow-elbow pairs that are of significance in this job. Waterhammer loads act on the elbow at 40 in the X direction and on the elbow at 135 in the Y-direction. In the SPECTRUM/TIME HISTORY FORCE SET input, force set #1 is defined as the load at 40 and force set #2 is defined as the load at 135. Add the response quantities from each load component first, using an ABS summation, and then the resulting modal response quantities second, using the grouping summation method. Two identical methods for achieving the same results are shown. Shock Name, Factor, Direction, Force set # BECAUSE THE “DIRECTION” INPUT IS THE SAME, I.E. “X”, FOR BOTH, LOAD CONTRIBUTIONS, THE DIRECTIONAL COMBINATION METHOD WILL GOVERN HOW THE HAMMER 40 AND HAMMER135 RESPONSES ARE COMBINED. HAMMER40, 1, X, 1 HAMMER135, 1, X, 2 DIRECTIONAL (ABS), MODAL(GROUP) BECAUSE THE “DIRECTION” INPUT IS DIFFERENT, I.E. “X” AND “Y,” THE SPATIAL COMBINATION METHOD WILL GOVERN HOW THE HAMMER40 AND HAMMER135 RESPONSES ARE COMBINED. NOTE THAT

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CAESAR II Technical Reference Manual

ON THE DIRECTIVE LINE THE “SPATIAL” DIRECTIVE COMES BEFORE THE “MODAL” DIRECTIVE. HAMMER40, 1, X, 1 HAMMER135, 1, Y, 2 SPATIAL(ABS), MODAL(GROUP)

Combining Static and Dynamic Results

Static/Dynamic Combinations

Load Case Defines the static or dynamic load case that is to be a part of this combination case. The load case label must always start with an S or a D for Static and Dynamic, and must be immediately followed by a load case number. Valid entries are: S1, STATIC1, S3, STATIC3, D1, DYNAMICS1, S#1, D#1, ...etc... The user can use any length up to 24 characters to define the load case label so long as the name starts in an S or a D, and ends in a valid load case number. For static load case definitions, the static case must exist and have already been run (also, the S can’t refer to a spring hanger design case). For dynamic load case definitions, the dynamic load case number refers to the shock load case. Several examples are given as follows.

Factor This entry is required and multiplies the response quantities from the respective static or dynamic run.

Chapter 5 Controlling the Dynamic Solution

33

The Stress Type drop list or the Directive button may be used to set optional extensions to global options set for all load cases on the control parameter spreadsheet. Typically the user will not need to specify any of these options. Some of the examples included on the following pages illustrate cases where these directives provide extra desired flexibility. STRESSTYPE (EXP) STRESSTYPE (SUS) STRESSTYPE (OPE) STRESSTYPE (OCC) STRESSTYPE (FAT) The user can change the default stress type for the combination case to any of the four shown here. The default stress type is OCC - occasional. COMBINATION (SRSS) COMBINATION (ABS) Defines how the load cases listed are to be combined. The ABS method takes the absolute value of all displacement, force, and stress data for each load case and adds them together. The SRSS method sums the square of all displacement, force, and stress data for each load case and then takes the square root of the result. Any number of separate static and dynamic cases can exist in the combination load case list provided each reference to a static or dynamic case is on a separate line. The order of input of the load case definitions is not important, and has no bearing on the results. Any number of user comment lines may be included. Static cases alone can be combined without dynamic cases. Dynamic cases alone can be combined without static cases. EXAMPLES: The static cases run in the job were: 1

=

W+P1+D1+T1+F1

(OPE)

2

=

W+P1+F1

(SUS)

3

=

L1 - L2

(EXP)

The dynamic cases run in the job were: 1

=

Operating Basis Earthquake

2

=

1/2 the Operating Basis Earthquake

The user must combine the Operating Basis Earthquake Stresses with the Sustained static stresses. The specification for this combination case is: STATIC2

1.0

DYNAMIC1

1.0

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CAESAR II Technical Reference Manual

S2

1

D1

1

The static cases run in the job were: 1

=

W + P1 + F1

(For hanger design)

2

=

W + P1 + D1 + T1 + F1

(For hanger design)

3

=

W + P1 + D1 + T1 + F1

(OPE)

4

=

W + P1 + F1

(SUS)

5

=

L3 - L4

(EXP)

Chapter 5 Controlling the Dynamic Solution

35

There was one dynamic load case. The user is required to turn an occasional case that is the sum of the sustained and the dynamic stresses using the SRSS combination method and the ABS combination method. Additionally, the user must combine the expansion static case and the dynamic case using the SRSS combination method. This is a total of three combination load cases. Note that since the job had hanger design the first two static load cases cannot be used in a combination case. The input for each case is shown as follows: COMBINATION CASE 1: *

SRSS COMBINATION OF SUSTAINED AND DYNAMIC CASES STRESSTYPE(OCC), COMBINATION(SRSS) STATIC4

1

DYNAMIC1

1

COMBINATION CASE 2: *

ABS COMBINATION OF SUSTAINED AND DYNAMIC CASES STRESSTYPE(OCC), COMBINATION(ABS) STATIC4

1

DYNAMIC1

1

COMBINATION CASE 3: *

SRSS COMBINATION OF EXPANSION AND DYNAMIC CASES STRESSTYPE(OCC), COMBINATION(SRSS) STATIC5

1

DYNAMIC1

1

The static cases run in the job were: 1

=

W+T1+P+D1+F1(OPE)

2

=

W+P+F1

3

=

U1

4

=

L1-L2

5

=

ST2+ST3

(OCC) ... Static seismic simulation

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CAESAR II Technical Reference Manual

The user is instructed to perform an SRSS combination of the static seismic case and both the sustained and operating static cases. The combination case lists for these two cases would appear: COMBINATION CASE 1: COMBINATION(SRSS), STRESSTYPE(OCC) STATIC2

1

STATIC3

1

COMBINATION CASES 2: COMBINATION(SRSS), STRESSTYPE(OCC) STATIC1

1

STATIC3

1

The following static load cases were run: 1

=

W+P1+F1

(Hanger design restrained weight case)

2

=

W+T1+F1+P1+D1

(Hanger design load case #1)

3

=

W+T2+F1+P1+D1

(Hanger design load case #2)

4

=

WNC+P1+F1

(Hanger design actual cold loads)

5

=

W+T1+F1+P1+D1

(OPE)

6

=

W+P1+F1

(SUS)

7

=

L5-L6

(EXP)

Spectrum/Time History Load Cases 1 through 6 were defined by the client. The static sustained stresses are to be combined with 1/2 the shock case 1 results, 1/2 the shock case 2 results, and 1.333 times the shock case 3 results. The combination method is to be SRSS. A second combination case is to combine 1/2 the shock case 4 results, 1/2 the shock case 5 results, and 1.333 times the shock case 6 results. These two combination load cases would be defined as shown as follows: COMBINATION CASE 1: COMBINATION(SRSS) STATIC6

1

DYNAMIC1

1/2

DYNAMIC2

1/2

DYNAMIC3

1.333

COMB(SRSS) S6

1

D1

0.5

Chapter 5 Controlling the Dynamic Solution

D2

0.5

D3

1.333

COMBINATION CASE 2: COMBINATION (SRSS) STATIC6

1

DYNAMIC4

0.5

DYNAMIC5

0.5

DYNAMIC6

1.333

37

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Spectrum Time History Force Maximum value of the dynamic load applied at this point. Units are as shown. Note that the total applied force will be the product of this value, the selected force value from the spectrum or load profile, and the factor entered for the load case.

Direction Direction of the dynamic load. Can be entered as X, Y, or Z or direction cosines or direction vectors. Direction cosines are entered in the form (cx,cy,cz), i.e. (0.707, 0, 0.707). Direction vectors are entered in the form: (vx, vy, vz), i.e. (1,0,1).

Node Node number where the force acts.

Force Set # Number to uniquely identify this particular force load pattern. See the examples that follow for clarification. This value defaults to 1. The general procedure for applying a force spectrum load is as follows: 1

Determine the pulse time history that acts at a single node or over a group of nodes. Only the pulse waveform must be the same for all nodes in group, the maximum pulse amplitude may vary. For example, a particular shock load due to ocean current loading acts over the nodes 5, 10, 15, 20, 25, and 30 on a production piping system, and the magnitude of the dynamic loading is 50 lb. at 5, 100 lb. at 10, 200 lb. at 15, and so on up to 500 lb. at 30. Also the dynamic load as a function of time at each point is equal to half of a sine wave with a period of one second. Even though the magnitude of the dynamic load varies over the nodes from 5 to 30, the pulse waveform does not (The pulse waveform is the half sine wave, and its shape is the same for each node). Thus the group of nodes from 5 to 30 can be included in the same force set #, each node having a different dynamic force magnitude.

2

Using the CAESAR II DLF Spectrum Generator build a DLF vs. frequency file for the time-pulse waveform.

3

Using the Spectrum Definitions option, define the DLF vs. frequency file just created as a Force spectrum data file with linear interpolation along the frequency axis and linear interpolation along the ordinate axis. (The DLF Spectrum Generator builds a standard shock table file. Until the type of shock data in the file is described to CAESAR II, the file can’t be used.) Remember to precede the shock name with a “#” sign when defining it in the Spectrum Definitions so that CAESAR II knows to read the shock table from the data file.

4

Determine the maximum force magnitude that acts on each node subject to the pulse load.

5

Using the Force Set Editor specify the maximum amplitude of the dynamic load, its direction, and the nodes it acts on.

Chapter 5 Controlling the Dynamic Solution

39

6

Build the Spectrum/Time History Load Cases by entering the Force spectrum name (this is the name that is preceded by the “#” sign, defined in the Spectrum Definitions editor), the table multiplication factor (usually 1.0), a direction (this is only a label used for output processing and should be characteristic of the shock, the actual force spectrum loads can act in multiple directions), and the Force Set #. (The Force Set # refers to the force pattern defined in the Force Spectrum Editor in step 5 above.) It is step 6 that defines the link between the force spectrum and the force loading pattern.

7

Setup any other parameters needed to run the spectrum analysis for this job. Perform error checking, and once there are no fatal errors, run the job.

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CAESAR II Technical Reference Manual

For a Time History analysis, the load profile used in step 2 would be entered directly in step 3, with the rest of the process remaining the same. Any number of user comment lines may be included. There can be any number of line entries in the Force spectrum data. If there are multiple force spectrum components in a single dynamic load case, the user should be particularly careful with the combination method selected. In this case, the same rules that cover earthquake shocks and components apply to force spectrum shocks and components. EXAMPLES: The nodes 5, 10, and 15 define a cantilever pipe leg that is part of an offshore production platform. The dynamic load as a function of time is equal to a half sine wave. The waveform is the same for all three nodes, but the maximum dynamic load on node 5 is 5030 lb., on node 10 is 10,370 lb., and on node 15 is 30,537 lb. Three force sets are to be built for this problem. One is with the dynamic loads acting in the X direction. One is with the dynamic loads acting in the Z direction, and the third is with the dynamic loads acting simultaneously in the X an Z directions. The force spectrum input data for this job is as follows: * X DIRECTION HALF SINE WAVE/CURRENT LOADING 5030

X

5

1

10370

X

10

1

30537

X

15

1

* Z DIRECTION HALF SINE WAVE/CURRENT LOADING 5030

Z

5

2

10370

Z

10

2

30537

Z

15

2

* X AND Z DIRECTION WAVE/CURRENT LOADING 5030

X

5

3

5030

Z

5

3

10370

X

10

3

10370

Z

10

3

30537

X

15

3

30537

Z

15

3

Chapter 5 Controlling the Dynamic Solution

41

A relief valve at node 565 is being investigated for several different reactor decompression conditions. The maximum load for the first condition is 320 kips in the X direction. This is a ramped time waveform. The valve opens and closes in 5 milliseconds. The duration for the first decompression condition is 50 milliseconds. The maximum load for the second decompression condition is 150 kips in the X direction. This also is a ramped time waveform. The valve opens and closes in 5 milliseconds and the duration for the second decompression condition is 4 seconds. The third decompression condition maximum load is 50 kips, and has the same time waveform as the second condition. (It is this decompression state that is expected to be the most frequent.) There must be two shock tables defined, one for the 50 ms duration waveform, and one for the 4 second duration waveform. Three different maximum force patterns are defined: * REACTOR DECOMP CONDITION 1 320000 X 565 1 * REACTOR DECOMP CONDITION 2 150000 X 565 2 * REACTOR DECOMP CONDITION 3 (MOST FREQUENT) 50000 X 565 3 A startup shock wave passes through a single elbow system. Nodes in the piping model are 5, 10, and 15. The system is shown as follows:

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CAESAR II Technical Reference Manual

As the wave starts off between 5 and 10 there is an initial dynamic axial load on the anchor at 5. When the shock wave hits the elbow at 10, the axial load in the 5-10 element balances the initial imbalance at node 5, and there becomes an axial imbalance in the 10-15 element. This shock load will be modelled as two completely separate impacts on the piping system The first is the dynamic anchor load at 5. (If 5 is a flexible anchor then this load may cause dynamic displacements of the piping system and 5 will just be subject to the dynamic time history pulse due to the shock.) Assume the anchor at 5 is a flexible vessel nozzle. The second shock load is the unbalanced dynamic pressure load in the 10-15 element that exists until the shock reaches the node 15. Friction in the line resisting movement of the shock wave is considerable. In the time the wave leaves the anchor at 5 until it encounters the bend at 10 there is a 50% drop in the pulse strength as shown in the following plot.

Chapter 5 Controlling the Dynamic Solution

43

This pressure drop was computed using a transient fluid simulator. Between node 10 and node 15 the pulse strength drops even further as shown as follows.

The Force Spectrum input for this loading is as shown as follows: * X DIRECTION LOAD ON FLEXIBLE ANCHOR AT 5 -5600 X 5 1 * Z DIRECTION LOAD ON ELBOW AT 10 2800 Z 10 2

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CAESAR II Technical Reference Manual

Lumped Masses

Lumped Masses

Mass Enter the concentrated mass in the units shown, a positive concentrated mass is added to the mass at the node. A negative concentrated mass is subtracted from the mass at the node and a zero entry deletes all mass for the node.

Direction Can be X, Y, Z, or ALL. ALL can be abbreviated “A”. If X, Y, or Z is entered, then the mass is only added or subtracted for that direction.

Start Node Node where the mass is to act. This entry is required. If entered without a stop node and increment, then this node must exist in the piping system. If entered with a stop node and increment then the range of nodes identified by the loop must include at least one node in the piping system. See the examples that follow.

Chapter 5 Controlling the Dynamic Solution

45

Stop Node Used as part of a “range of nodes” lumped mass command. See the examples that follow. This entry is optional.

Increment Used as part of a “range of nodes” lumped mass command. See the examples that follow. This entry is optional. There can be any number of line entries in the lumped mass data. The zero mass capability with the “range of nodes” entry is particularly useful when the user has a part of the system for which he is not interested in the modes. That part of the system would have been modeled for its stiffness effect only. One example is structural steel models. It is not uncommon for a user to delete all of the mass for nodes in the structural steel model. (Steel models are often only entered to include their stiffness effects and so the omission of their dynamic effects is often not significant.) EXAMPLES: 450 ALL 40 Note: The node range loop starts from node 12, which is not defined and goes through node 25 in steps of 1. Some nodes don’t exist in this range but this is not an error as long as at least one node in the range defined by 12 through 25 by 1, exists in the system. 0.0 ALL 12 25 1 375 A 25 50 5 0.0

X

1

600

1

0.0

Y

1

600

1

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CAESAR II Technical Reference Manual

Snubbers

Snubbers

Stiffness Enter the stiffness for the snubber in the units shown. If the snubber is rigid enter a value of 1.0E12. The stiffness of the snubber must be given and must be positive.

Direction Enter the line of action of the snubber as either X, Y, Z, or as direction cosines or direction vectors. The format for direction cosines is (cx,cy,cz), and for direction vectors is (vx, vy, vz). See the example that follows for the entry of some typical skewed snubbers.

Chapter 5 Controlling the Dynamic Solution

47

Node Enter the node where the snubber acts. This is a required entry. If the snubber acts between the piping system and a fixed point in space, then leave the CNode field blank. Connecting Nodes work for snubbers just like they do for restraints.

CNode If the snubber acts between one point on the piping system and another point on the piping system, then enter the node that the snubber connects to. EXAMPLES:

1

Add rigid snubber at node 150 in the Z direction. 1E12 Z 150

2

Add rigid snubbers at nodes 160, 165, and 170 in the Z direction. 1E12 Z 160 1E12 Z 165 1E12 Z 170

3

Add a rigid snubber between the structural steel node 1005 and the piping node 405 in the Z direction. 1E12 Z 405 1005

4

Add a 5,000 lb./in. snubber in the X and Y directions at the piping node 500. The X snubber should connect to the structural steel node 1050 and the Y snubber should connect to the overhead line at node 743. HORIZONTAL SNUBBER BETWEEN STEAM LINE AND STEEL 5000 X 500 1050.

LINE

VERTICAL SNUBBER BETWEEN STEAM LINE AND OVER HEAD COOLING WATER 5000 Y 500 743

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Dynamic Control Parameters

Control Parameters

The type of analysis chosen by the user in the Dynamic Input Processor determines the active Control Parameters. CAESAR II will display only this list of active Control Parameters. In addition, the calculation details can be fine-tuned using many of the other Control Parameters, maximizing accuracy of results for most dynamic problems. The impact and use of these parameters, as well as their technical bases, are described in this section. The list of the control parameters, along with the Analysis Types for which they are active, is shown in the following table.

Chapter 5 Controlling the Dynamic Solution

49

Notes:

X-required 1-if system has nonlinear restraints or hanger design 2-if any restraints have friction 3-either "Max. No. of Eigenvalues" or "Frequency Cutoff" required 4-if modal combination method is GROUP or 10% 5-if modal combination method is DSRSS 6-if USNRC Regulatory Guide 1.60 or Uniform Building Code seismic spectra are used 7-if independent support movement (USM) loads are present 8-if pseudo-static components are inducted 9-if missing mass components are included 10-if multiple spectrum loads are applied in the same direction

Analysis Type (Harmonic/Spectrum/Modes/Time-History) The first parameter is used to select from the available dynamic analysis types, which are Harmonic (direct solution), Response Spectrum (any combination of seismic, anchor movement, and force loadings), Modal Extraction, Range, and Time History (linear modal). These analysis types are described below:

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CAESAR II Technical Reference Manual

Harmonic Analysis Generally, the response of a system to a dynamically applied load is expressed through the dynamic equation of motion:

Where: M =

system mass matrix =

C

=

acceleration vector, as a function of time

system damping matrix =

velocity vector, as a function of time

K =

system stiffness matrix

x(t) =

displacement vector, as a function of time

F(t) =

applied load vector, as a function of time

Unfortunately, this differential equation cannot be solved explicitly, except in a few specific cases. Harmonic analysis looks at one of these cases—the set of dynamic problems where the forces or displacements (i.e., pulsation or vibration) acting on the piping system take sinusoidal forms. Under harmonic loading, when damping is zero, the dynamic equation of the system can be reduced to M (t) + K x(t) = F0 cos ( t + Q) Where: F0 = t

harmonic load vector

=

angular forcing frequency of harmonic load (radian/sec)

=

time

Q =

phase angle (radians)

This differential equation can be solved directly, yielding the nodal displacements at any time (and therefrom, the system reactions, forces and moments, and stresses). The equation has a solution of the form x (t) =

A cos ( t + Q)

Where: A =

vector of maximum harmonic displacements of system

Since acceleration is the second derivative of displacement with respect to time, (t) =

-A

2

cos

t

Inserting these equations for displacement and acceleration back into the basic harmonic equation of motion yields, -M A

2

cos ( t + Q) + K A cos ( t + Q) = Fo cos ( t + Q)

Chapter 5 Controlling the Dynamic Solution

51

Dividing both sides of this equation by cos ( t + Q), -M A

2

+ K A = Fo

Reordering this equation, ) A = Fo

(K - M

2

This is exactly the same form of the equation as is solved for all linear (static) piping problems. The appealing thing about this is that the solution time for each excitation frequency takes only as long as a single static solution, and, when there is no phase relationship to the loading, the results give the maximum dynamic responses directly. Due to the speed of the analysis, and because the solutions are so directly applicable, it is advisable to make as much use of this capability as possible. Two considerations must be kept in mind: When damping is not zero, the harmonic equation can only be solved if the damping matrix can be defined as the sum of multiples of the mass and stiffness matrix (Rayleigh damping), i.e.: [C] = a [M] + b [K] On a modal basis, the relationship between the ratio of critical damping Cc and the constants a and b is given as

Cc =

2

+

2

Where: = Undamped natural frequency of mode (rad/sec) For practical problems, to

is extremely small, and so may be ignored. Therefore the definition of

reduces

= 2 Cc/ CAESAR II uses this implementation of damping for its harmonic analysis; however there are still two problems. First, for multi-degree-of-freedom systems, there is not really a single b, but there must be only a single b in order to get a solution of the harmonic equation. The second problem is that the modal frequencies are not known prior to generation of the damping matrix. Therefore the w used in the calculation of b is the forcing frequency of the load, instead of the natural frequency of a mode. When the forcing frequency of the load is in the vicinity of a modal frequency, this gives a good estimation of the true damping.

If multiple harmonic loads occur simultaneously, and they are not in phase, system response is the sum of the responses due to the individual loads: x(t) = S Ai cos ( t + Qi) Where: Ai = displacement vector of system under load i Qi = phase angle of load i

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CAESAR II Technical Reference Manual

In this case, an absolute maximum solution cannot be found. Rather, solutions for each load, and the sum of these, must be found at various times in the load cycle. These combinations should then be reviewed in order to determine which one causes the worst load case. Alternatively, CAESAR II can select the frequency/phase pairs which maximize the system displacement. Note:

Damped harmonics will always cause a phased response.

The biggest use by far of the harmonic solver is in analyzing low frequency field vibrations resulting from either fluid pulsation or out-of-round rotating equipment displacements. The approach typically taken towards solving this type of problem is described briefly below: 1

A potential dynamic problem is first identified in the field—either in terms of large cyclic vibrations or high stresses (fatigue failure) being present in an existing piping system, raising questions of whether this represents a dangerous situation. As many symptoms of the problem (quantifiable displacements, overstress points, etc.) are identified as possible, for future use in refining the dynamic model.

2

A model of the piping system is built using CAESAR II. This should be done as accurately as possible, since system, as well as load, characteristics affect the magnitude of the developed response. Particular attention should be paid when modeling the area where the vibration occurs. This might include accurately representing valve operators, flange pairs, orifice plates and other in-line equipment. It may also be a good idea to add additional nodes in the area of the vibration.

3

The engineer next postulates the cause of the load, and from that, an estimate of the frequency, magnitude, point, and direction of the load. This is somewhat difficult because the dynamic loads can come from many sources. Dynamic loads may be due to internal pressure pulses, external vibration, flow shedding at intersections, two phase flow, etc., but in almost all cases, there is some frequency content of the excitation that corresponds to (and therefore excites) a system mechanical natural frequency. If the load is caused by equipment, then the forcing frequency is probably some multiple of the operating frequency; if the load is due to acoustic flow problems, then the forcing frequency can be estimated through the use of Strouhal’s equations (from fluid dynamics). Using the best assumptions available, the user should estimate the magnitudes and points of application of the dynamic load.

4

The loading is then modeled using harmonic forces or displacements (normally depending upon whether the cause is assumed to be pulsation or vibration) and several harmonic analyses are done, sweeping the frequencies through a range centered about the target frequency (in order to account for uncertainty). The results of each of the analyses are examined for signs of large displacements, indicating harmonic resonance. If the resonance is present, the results of the analysis are compared to the known symptoms from the field. If they are not similar (or if there is no resonance), this indicates that the dynamic model is not a good one, so it must be improved, either in terms of a more accurate system (static) model, a better estimate of the load, or a finer sweep through the frequency range. Once the model has been refined, this step is repeated until the mathematical model behaves just like the actual piping system in the field.

5

At this time, there is a good model of the piping system and a good model of the loads (or, more accurately, a good model of the relationship of the load characteristics to the system characteristics). The results of this run are evaluated in order to determine whether they indicate a problem. Since harmonic stresses are cyclic, they should be evaluated against the endurance limit of the piping material; displacements should be reviewed against interference limits or esthetic guidelines.

Chapter 5 Controlling the Dynamic Solution

6

53

If the situation is deemed to be a problem, its cause must be identified, where the cause is normally the excitation of a single mode of vibration. For example, the Dynamic Load Factor for a single damped mode of vibration, with a harmonic load applied is

DLF =

1 + (2Cc [1 (

f

m)

2

f

] + (2Cc

m)

2

f

m)

2

Where: DLF = dynamic loading factor Cc = ratio of system damping to “critical damping,” where “critical damping” = f

= forcing frequency of applied harmonic load

n

= natural frequency of mode of vibration

A modal extraction of the system is done; one (or more) of these modes should have a natural frequency close to the forcing frequency of the applied load. The guilty mode can be further identified as that one having a shape very similar to the shape of the total system vibration, since this mode shape has certainly been dynamically magnified far beyond the other modes (and thus predominates in the final vibrated shape). 7. Once the guilty mode has been identified, it must be eliminated. This is done most easily by adding a restraint at a high point (and in the direction thereof) of the mode shape. If this cannot be done, the mode may also be altered by changing the mass distribution of the system. If no modification of the system is possible, it may be possible to alter the forcing frequency of the load. If the dynamic load was postulated to be due to internal acoustics, it is recommended that the pipe not be rerouted at this point, as rerouting the pipe will change the internal flow conditions (which may resolve or amplify the problem, but in either case will void CAESAR II’s “good model” of the system). After modifying the system, the harmonic problem (using the single forcing frequency determined as a “good model”) is then re-run, and the stresses, displacements, etc. are re-evaluated. 8. If the dynamic problem has been adequately solved, the system is now re-analyzed statically to determine the effects of any modifications on the static loading cases. (Remember, adding restraint normally increases expansion stresses, while adding mass increases sustained stresses.) The user may process output from a harmonic analysis in two ways: Use of the output processor to review displacement, restraint, force, or stress data either graphically or in report form. Animation of the displacement pattern for each of the frequency load cases. Note: The results of harmonic dynamic loads cannot be combined using the Static/Dynamic Combination option.

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Spectrum Analysis A spectrum analysis represents an attempt to estimate the maximum response developed in a system during a transient load. The results are a statistical summation of the maximum displacements, forces, reactions, stresses, etc; the individual responses do not represent an actual physical loading case in that the maxima may all occur at different times. Spectrum analyses are especially useful when the loading profile is random, or otherwise not known exactly, such as with seismic loads. CAESAR II provides the ability to perform two types of spectrum analyses (which may be combined): for seismic and force loadings. Seismic loadings may be evaluated either uniformly over the entire system, or applied through individual support groups (with corresponding anchor movements). Force spectra analyses may be used to analyze impulse loadings, such as those due to relief valve, fluid hammer, or slug flow. These two types are described in the following paragraphs. Seismic Spectrum Analysis. Seismic loads cannot be solved through time history analyses, since earthquakes cause random motion, which may be different for each earthquake, even those occurring at the same site. To simplify the analytical definition of the earthquake, it is necessary to get the expected random waveform of acceleration (or velocity or displacement) vs. time into some simple frequencycontent plot. The most predominantly used frequency-content plot is the response spectrum. A response spectrum for an earthquake load can be developed by placing a series of single degree-of-freedom oscillators on a mechanical shake table and feeding a “typical” (typical for a specific site) earthquake time history through it, measuring the maximum response (displacement, velocity, or acceleration) of each oscillator. The expectation is that even though all earthquakes are different, similar ones should produce the same maximum responses, even though the time at which they occur will differ with each individual occurrence. (Responses will be based on the maximum ground displacement and acceleration, the dynamic load factors determined by the ratios of the predominant harmonic frequencies of the earthquake to the natural frequencies of the oscillators, and system damping.) Response spectra for a number of damping values can be generated by plotting the maximum response for each oscillator. A plot of a set of typical response spectra is shown in the following figure.

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Seismic response spectra resemble harmonic Dynamic Load Factor curves, since seismic loads evidence strong harmonic tendencies. As damping value increases, the system response approaches the ground motion. Seismic spectra usually also show strong evidence of flexible, resonant, and rigid areas. Spectra may have multiple peaks due to filtering by the building and/or piping system; however multiple peaks are usually enveloped in order to account for uncertainties in the analysis. Seismic response spectra peaks are typically spread to account for inaccuracies as well. The idea behind the generation of the response spectra is that a system’s modes of vibration will respond to the load in the exact same manner as will a single degree-of-freedom oscillator. System response may be plotted in terms of displacement, velocity, or acceleration, since these terms of the spectra are all related by the frequency: d=v/

=a/

2

Where: d = displacement from response spectrum at frequency v = velocity from response spectrum at frequency = angular frequency at which response spectrum parameters are taken a = acceleration from response spectrum at frequency Response Spectrum analysis proceeds according to the following steps: 1

Modes of vibration are extracted from the system using an Eigensolver algorithm. Each mode has a characteristic frequency and mode shape.

2

The maximum response of each mode under the applied load is determined from the spectrum value corresponding to the mode’s natural frequency.

3

The total system response is determined by summing the individual modal responses, using methods that reflect the time independence of the responses and the portion of system mass allocated to each mode.

There are four major sources of earthquake spectra available to the CAESAR II user: Predefined El Centro (available in the CAESAR II database—spectrum name = ELCENTRO): This data is taken from J. Biggs’ Introduction to Structural Dynamics and is based on the north-south component of the May 18, 1940 El Centro California earthquake. The recorded maximum acceleration was 0.33 g. The spectrum provided here is intended to apply to elastic systems having 5 to 10 percent critical damping. Predefined Nuclear Regulatory Guide 1.60 (Available in the CAESAR II database): The predefined spectrum names are: 1.60H.5

1.60V.5

--

1.60H2

1.60V2 --

Horizontal/vertical,2.0% damping

1.60H5

1.60V5 --

Horizontal/vertical,5.0% damping

1.60H7

1.60V7 --

Horizontal/vertical,7.0% damping

1.60H10 1.60V10

--

Horizontal/vertical,0.5% damping

Horizontal/vertical,10.0% damping

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These spectra are constructed according to the instructions given in Regulatory Guide 1.60 for seismic design of nuclear plants. They must also be scaled up or down by the maximum ground acceleration (ZPA—zero period acceleration), which can be specified in the CAESAR II control parameter spreadsheet. Predefined Uniform Building Code (Available in the CAESAR II database). The predefined spectrum names are: UBCSOIL1

Spectrum for rock and stiff soils

UBCSOIL2

Spectrum for deep cohesionless or stiff clay soils

UBCSOIL3

Spectrum for soft to medium clays and sands

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These spectra represent the normalized response spectra shapes (for three soil types) provided in Figure 23-3 of the Uniform Building Code (1991 Edition). When used, they must be scaled by the ZPA, which is the product of Z and I (Where Z is the seismic zone coefficient and I is the earthquake importance factor, from UBC Tables 23-I and 23-L, respectively). The ZPA can be specific using the CAESAR II control parameter spreadsheet. User defined spectra: User defined spectra may be entered with period or frequency as the range, and displacement, velocity, or acceleration as the ordinate. These spectra may be read in from a text file or entered directly into a spectrum table during dynamic input processing. Independent Support Motion Applications. Earthquake ground motions are caused by the passing of acoustic shock waves through the earth’s soil. These waves are usually hundreds of feet long. If supports having foundations in the soil are grouped together within a several hundred foot radius of each other they will typically see exactly the same excitation from the earthquake. If all of the supports for a particular piping system are attached directly to ground type supports, each support will be excited by an essentially identical time waveform. This type of excitation is known as uniform support excitation. Often pipe is supported from rack, building, or vessel structures as well as from ground type supports. These intermediate structures serve to, in some cases, filter and in some cases accentuate the effect of the earthquake. In this situation, the supports attached to the intermediate structure are not exposed to the same excitation as those that are attached directly to ground foundations. To accurately model these systems different shocks must be applied to different parts of the piping system. This type of excitation is known as independent support motion (ISM) excitation. While the different support groups are exposed to different shocks, there are also relative movements between support groups that don’t exist for uniform support excitation. The movement of one support group relative to another is termed pseudostatic displacement, or seismic anchor movements. For uniform support excitation there are spatial and modal response components available for combination. For independent support excitation there are spatial and modal response components available for each different support group, plus pseudostatic components of the earthquake that must be added into the dynamic response as well. The major difference when running ISM type earthquake loads comes while building the shock load cases. Whereas in the uniform excitation case the shock acts implicitly over all of the supports in the system, in the ISM case different shocks act on different groups of supports. The shock load case input form appears: Shock Name Factor

Dir

Start Node

Stop Node

Incr

Anchor Mvmt

Name, Factor, and Direction are all that is entered for uniform support excitations. For ISM type shocks, the group of nodes over which the shock acts must be specified as well, using the Start Node, Stop Node, and Increment entries. The Anchor Movement entry is used to explicitly define the seismic displacement of the restraint set. This displacement is used to calculate the pseudostatic load components. If omitted, the program defaults to the displacement derived from the response spectrum entry corresponding to the lowest frequency. Force Spectrum Analysis. A similar method can be followed for non-random loads, such as an impulse load for which the force vs. time profile is known. A look at the equation for the earthquake problem explains why the force spectrum solution is very similar to the earthquake solution:

Mx(t ) + Kx(t ) = Mxg (t ) The term on the right hand side is nothing more than a dynamic force acting on the piping system, i.e. F = Ma, so the analogous equation to be solved for the force spectrum problem is: Mx(t ) + Kx (t ) = F (t )

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Where: F = the dynamic load (water hammer or relief valve) Instead of the displacement, velocity, or acceleration spectrum used for the seismic problem, a Dynamic Load Factor spectrum is used for a force spectrum problem. A DLF spectrum gives the ratio of the maximum dynamic displacement divided by the maximum static displacement. Whereas the earthquake response spectrum analysis method started with the time history of an earthquake excitation, the force spectrum analysis method is done in exactly the same way—except that the analysis starts with the force vs. time profile. Just as for the earthquake, this time history loading can be applied to a shake table of single degree-of-freedom bodies, with a response spectrum (in this case, DLF vs. natural frequency) being generated by dividing the maximum oscillator displacements by the static displacements expected under the same load. An alternate means of generating a response spectrum for an impulse load is to numerically integrate the dynamic equation of motion for oscillators of various frequencies under the applied load. This can be done using the Pulse Table/DLF Spectrum Generator available from the CAESAR II Main Dynamics Menu. The user may process output from a spectrum analysis in two ways: Use of the output processor to review the natural frequencies, mode shapes, participation factors, included mass/force, displacements, restraint loads, forces, or stresses in report form. Dynamic results also show the largest modal contributor, along with the mode and shock load responsible for that contribution. Animation of the individual mode shapes extracted for the spectrum analysis. Modal Extraction. A modal extraction performs only an Eigensolution (an eigensolution is also performed as the initial step of the spectrum or modal time history analyses). The Eigensolution algorithm uses an iterative method to solve for natural frequencies and mode shapes of a piping or structural system. Each mode of the piping system is associated with a shape and a frequency, which together define the system’s tendency to vibrate; the mode shape defining the shape the system would like to take when it vibrates, and the natural frequency defining the desired speed of the vibration. The eigensolver returns a set of these for each mode, with the dimensionless mode shape called an eigenvector, and the frequency returned as the square of the angular frequency ( 2), known as the eigenvalue. Given the eigenvalue, the modal frequency can be expressed in angular frequency (radians per second), cyclic frequency (Hz), or period (seconds per cycle): (radians squared per second squared)

eigenvalue

=

2

angular frequency

=

(radians per second)

cyclic frequency

=

/ 2 (Hz, or cycles per second)

period

=

2 /

(seconds per cycle)

The absolute magnitude of a mode shape displacement computed by an eigensolver is unknown, with only the shape being given (i.e. only the ratios of the displacements at various degrees of freedom are known for each mode, with these ratios being constant for each mode). One eigenpair can potentially be calculated for each degree of freedom in the model that contains some nonzero mass (node point) and some non-rigid stiffness (i.e., is not fully restrained). CAESAR II omits rotational degrees of freedom from dynamic models in order to simplify the calculation—this is usually acceptable since rotational modes of vibration usually have very high frequencies, and correspondingly very low mode participation factors. The user may process output from a modal analysis in two ways: Use of the output processor to review the natural frequencies and mode shapes in report form. Animation of the individual mode shapes.

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Time History Time history analysis is a more accurate, more computationally intensive analytical method than is response spectrum analysis, and is best suited to impulse loadings or other transient loadings where the profile is known. This method of analysis involves the actual solution of the dynamic equation of motion throughout the duration of the applied load and subsequent system vibration, providing a true simulation of the system response at all times. As noted previously, the dynamic equation of motion for a system is

Mx(t ) + Cx(t ) + Kx(t ) = F (t )

This differential equation cannot be solved explicitly, but may be integrated using numeric techniques by slicing the duration of the load into many small time steps. Based on an assumption of the behavior of the system between time slices (i.e., that the change in acceleration between time slices is linear), the system accelerations, velocities, displacements, and correspondingly, the reactions, internal forces, and stresses can be calculated at successive time steps. Since the total response of a system is equivalent to the sum of the responses of its individual modes of vibration, the above equation can be simplified (assuming the damping matrix C is orthogonal), using the transformation x = FX, to be expressed in modal coordinates:

x(t ) + C x(t ) + gx(t ) = h1 F (t ) Where: x(t)

=

C´ = i

ci

acceleration vector (in modal coordinates), as a function of time

diagonal damping matrix, where entry C´i =

i

=

angular frequency of mode i

=

ratio of damping to critical damping for mode i

ci

(t) =

velocity vector (in modal coordinates), as a function of time

x(t) =

displacement vector (in modal coordinates), as a function of time

=

diagonal stiffness matrix, where entry

i

=

i

2

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This transformation represents N (where N is the number of modes of vibration extracted) uncoupled second order differential equations, which can then be integrated and summed (using the in-phase, algebraic summation method) to give the total system response. The CAESAR II program uses the Wilson method (an extension of the Newmark method) to integrate the equations of motion, which provides an unconditionally stable algorithm, regardless of time step size chosen. Only one dynamic load may be defined for a time history analysis (this dynamic load case may be used in as many static/dynamic combination load case as necessary). However, the single load case may consist of multiple force profiles applied to the system simultaneously, or sequentially. Each force vs. time profile is entered as a spectrum with an ordinate of FORCE (in current units) and a range of TIME (in milliseconds). The profiles are defined by entering the time and force coordinates of the corner points defining the profile. (Note that a time can only be entered once, and that times with zero force outside of the defined profile need not be entered explicitly.) For example, the profiles shown in the following figure are entered as: TIME (MS)

FORCE

TIME (MS)

FORCE

0.0

0.0

20.0

1000.0

10.0

300.0

60.0

1000.0

20.0

1000.0

30.0

0.0

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The load profiles must then be linked with force sets (indicating magnitude, direction, and location of the applied load) in the shock case. The magnitude of the applied load is determined by the product of the profile force, the force set magnitude, and the scale in the shock case. Currently only forces, not moments or restraint displacements, may be entered in the time history load profile. However, moments can be modeled using force couples, and restraint displacements can be simulated by entering forces equal to the desired displacement times the restraint stiffness in the direction of the displacement). The user may process output from a Time History analysis in three ways: 1

Use of the output processor to review the natural frequencies, mode shapes, participation factors, included mass/force, displacements, restraint loads, forces, or stresses in report form. CAESAR II’s implementation of time history analysis provides two types of results—one results case containing the maximum individual components (axial stress, X-displacement, MZ reaction, etc.) of the system response, along with the time at which it occurred, and several (the actual number is determined by user request) results cases representing the actual system response at specific times. Dynamic results also show the largest modal contributor, along with the mode and transient load responsible for that contribution.

2

Animation of the shock displacement for the transient load cases. During animation, the displacements, forces, moments, stresses, and other data associated with individual elements may be displayed at every time step and for the dynamic load alone, or for any of the static/dynamic combinations.

3

Animation of the individual mode shapes included in the time history response.

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Static Load Case for Nonlinear Restraint Status (Active for: Harmonic, Spectrum, Modal, Range, and Time History) Currently all of CAESAR II’s dynamic analyses act only on linear systems, so any non-linearities must be linearized prior to analysis. This means that one-directional restraints will not lift off and reseat, gaps will not open and close, and friction will not act as a constant effort force. Therefore, for dynamic analyses, all non-linear effects must be modeled as linear—for example, a one-directional restraint must be modeled as either seated (active) or lifted off (inactive), and a gap must be either open (inactive) or closed (active). This process is automated when the static load case is selected here—CAESAR II automatically activates the non-linear restraints in the system to correspond to their status in the selected load case (the user may think of this as being the loading condition—for example Operating—of the system at the time at which the dynamic load occurs). It must be noted that this automated linearization does not always provide an appropriate dynamic model, and it may be necessary to select other static load cases or even to manually alter the restraint condition in order to simulate the correct dynamic response. A static load case must precede the dynamics job whenever one or more of the following situations occur: There are spring hangers to be designed in the job. The static runs must be made in order to determine the spring rate to be used in the dynamic model. There are non-linear restraints, such as one-directional restraints, large-rotation rods, bi-linear restraints, gaps, etc. in the system. The static analysis must be made in order to determine the active status of each of the restraints for linearization of the dynamic model. There are frictional restraints in the job, i.e. any restraints with a nonzero j (mu) value. The most common arrangement of static loads during typical CAESAR II analyses are shown below: Example 1—analysis containing no hanger design: 1 = W+P1+D1+T1+F1 (OPE) 2 = W+P1+F1 (SUS) 3 = L1-L2 (EXP) In this case, if the operating condition is most likely to exist throughout the duration of the dynamic transient, the correct entry for this parameter is 1. If the installed condition is more likely to exist during the transient, the entry for this parameter should be 2. It is extremely unlikely that the expansion case (3) would be correct here, since it does not represent the system status at any given time, but rather represents the difference between the first two cases. Example 2—analysis containing hanger design: 1 = W+P1+F1 (For hanger design) 2 = W+P1+D1+T1+F1 (For hanger design) 3 = W+P1+D1+T1+F1 (OPE) 4 = W+P1+F1 (SUS) 5 = L3-L4 (EXP) In this case, the correct static load cases to use are those in which the selected spring hangers have been included; if the operating condition is the correct load case, the entry for this parameter should be 3. For the installed condition, an entry of 4 is correct.

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Stiffness Factor for Friction (0.0 - Not Used) (Active for: Harmonic, Spectrum, Modal, Range, and Time History) As noted above, all of CAESAR II’s dynamic analyses are currently linear, so non-linear effects must be linearized. Modeling of friction in dynamic models presents a special case, since friction actually impacts the dynamic response in two ways—static friction (prior to breakaway) affects the stiffness of the system, by providing additional restraint, while kinetic friction (subsequent to breakaway) actually affects the damping component of dynamic response; due to mathematical constraints, damping is ignored for all analyses except time history and harmonics (for which it is only considered on a system-wide basis). CAESAR II allows friction to be taken into account through the use of this Friction Stiffness Factor. CAESAR II approximates the restraining effect of friction on the pipe by including stiffnesses transverse to the direction of the restraint at which friction was specified. The stiffness of these “frictional” restraints is computed as: Kfriction = (F) (j) (Fact) Where: Kfriction = stiffness of frictional restraint inserted by CAESAR II F

= the force at the restraint taken from the static solution

j

= mu, friction coefficient at restraint, as defined in the static model

Fact = Friction Factor from the control spreadsheet This factor should be adjusted as necessary in order to make the dynamic model simulate the system’s actual dynamic response (note that use of this factor does not correspond to any actual dynamic parameter, but is actually a “tweak” factor to modify system stiffness). Entering a friction factor greater than zero causes these friction stiffnesses to be inserted into the dynamics job. Increasing this factor correspondingly increases the effect of the friction. Entering a friction factor equal to zero ignores any frictional effect in the dynamics job.

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Max. No. of Eigenvalues Calculated (0-Not used) (Active for: Spectrum, Modal, and Time History) The first stage of the Spectrum, Modal, and Time History analyses, is the use of the Eigensolver algorithm to extract the piping system’s natural frequencies and mode shapes. For the Spectrum and Time History analyses, the response under loading is calculated for each of the modes, with the system response being the sum of the individual modal responses. Obviously, the more modes that are extracted, the more the sum of those modal responses resembles the actual system response. The problem is that this algorithm uses an iterative method for finding successive modes, so extraction of a large number of modes usually requires much more time than does a static solution of the same piping system. The object is to extract sufficient modes to get a suitable solution, without straining computational resources. CAESAR II permits the user to specify—either through a mode number cutoff or a frequency cutoff—the number of modal responses to be included in the system results. This parameter is used, in combination with the Frequency Cutoff described below, to limit the maximum number of modes of vibration to be extracted during the dynamic analysis. If this parameter is entered as 0, the number of modes extracted is limited only by the frequency cutoff (and potentially, the number of degrees-of-freedom in the system model). If the analyst is more interested in providing an accurate representation of the system displacements, it may only be necessary to request the extraction of a few modes, allowing a rapid calculation time. However, if an accurate estimate of the forces, stresses, etc. in the system is the objective, calculation time grows as it becomes necessary to extract far more modes. This is particularly true in the case when solving a fluid hammer problem in the presence of axial restraints; often modes with natural frequencies of up to 300 Hz can be large contributors to the solution. The usual procedure for determining how many modes are sufficient is to extract a certain number of modes and review the results; then to repeat the analysis while extracting 5 to 10 additional modes, and comparing the new results to the old. If there is a significant change between the results, a new analysis is made, again extracting 5 to 10 more modes above those that were extracted for the second analysis. This iterative process continues until the results taper off, becoming asymptotic. This procedure has two drawbacks, the first one obvious—the time involved in making the multiple analyses, as well as the time involved in extracting the potentially large number of modes. The second drawback, occurring with Spectrum analysis, is less obvious—a degree of conservatism is introduced when combining the contributions of the higher order modes. Possible spectral mode summation methods include SRSS, ABSOLUTE, and GROUP—all methods that combine modal results as same-sign (positive) values. In reality, theory states that the rigid modes actually act in phase with each other, and should therefore be combined algebraically, thus permitting the response of some rigid modes to cancel the effect of other rigid modes (this is actually what occurs in a time history analysis). Because of this conservatism, it is actually possible to get results which exceed twice the applied load, despite the fact that the Dynamic Load Factor (DLF) of an impulse load cannot be greater than 2.0. An alternative method of ensuring that sufficient modes are considered in the dynamic model is through the use of the Included Mass Data Report. This report (available from the Dynamic Output Screen) is compiled for all spectrum and time history shock cases, whether missing mass (see description in the section Include Missing Mass Components) is to be included or not. It displays the percent of system mass along each of the three global axes, as well as the percent of total force, which has been captured by the extracted modes. The percent of system mass active along each of the three global axes (X-, Y-, and Z-) is calculated by summing the modal mass (corresponding to the appropriate directional degree-of-freedom) attributed to the extracted modes and dividing that sum by the sum of the system mass acting in the same direction:

Chapter 5 Controlling the Dynamic Solution

% Active Massx

M e [i ]

= 100(

65

M [ i ])

summed over i = 1 to n, by 6 (X-direction degrees of freedom)

% Active MassY

M e [i ]

= 100(

M [ i ])

summed over 1 = 2 to n, by 6 (Y-direction degrees of freedom)

% Active Massz

= 100(

M e [i ]

M [ i ])

summed over 1 = 3 to n, by 6 (Z-direction degrees of freedom)

Where: Me = masses

vector (by degree-of-freedom) of sum (over all extracted modes) of effective modal

M =

vector corresponding to main diagonal of system mass matrix

The maximum possible percent of active mass which is theoretically possible is of course 100%, with 9095% usually indicating that a sufficient number of modes have been extracted to provide a good dynamic model. The percent of active force is calculated by the following factors: separately summing the components of the effective force acting along each of the three directional degrees-of-freedom combining them algebraically doing the same for the applied load taking the ratio of the effective load divided by the applied load For example: Fex = Fe[i] Fx = F[i]

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summed over i = 1 to n, by 6 (X - direction degrees of freedom) Fey = Fe[i] Fy = F[i] summed over i = 2 to n, by 6 (Y - direction degrees of freedom) Fez = Fe[i] Fz = F[i] summed over i = 3 to n, by 6 (Z - direction degrees of freedom)

= 100* % Active Force

[ Fe x 2 + Fe y 2 + Fe z 2 ] [ Fx 2 + Fy 2 + Fz 2 ]

Where: = effective force (allocated to extracted modes) acting along the global X-, Y-, FeX,FeY,FeZ and Z-axes, respectively Fr =

vector of effective forces (allocated to extracted modes)

FX,FY,FZ

=

F

vector of total system forces

=

total system forces acting along the global X-, Y-, and Z-axes, respectively

The maximum possible percent which is theoretically possible for this value is also 100%; however, in practice it may be higher, indicating an uneven distribution of the load and mass in the system model. There is nothing inherently wrong with an analysis where the included force exceeds 100%—if the missing mass correction is included, the modal loadings will be adjusted to conform to the applied loading automatically. Often the percent of included force can be brought back under 100% by extracting a few more modes. At other times, the situation can be remedied by improving the dynamic model through a finer element mesh, or, more importantly, equalizing the mass point spacing in the vicinity of the load.

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Frequency Cutoff (HZ) (Active for: Spectrum, Modal, and Time History) As noted above, CAESAR II permits the user to specify either a number of modes or a frequency cutoff for extracting modes to be considered in the dynamic analysis. Modal extraction ceases when the Eigensolver extracts either the number of modes requested, or extracts a mode with a frequency above that of the Frequency Cutoff, whichever comes first. One recommendation for selection of a frequency cutoff point is that the user extract modes up to, but not far beyond, a recognized “rigid” frequency, and then include the missing mass correction (discussed in the section Include Missing Mass Components). Choosing a cutoff frequency to the left of the response spectrum’s resonant peak will provide a non-conservative result, since resonant responses may be missed. During spectrum analysis, using a cutoff frequency to the right of the peak, but still in the resonant range, will yield either overly- or underly-conservative results, depending upon the method used to extract the ZPA from the response spectrum. (In the case of time history analysis, selecting a cutoff frequency to the right of the peak, but still in the resonant range, will probably yield non-conservative results, since the missing mass force is applied with a dynamic load factor of 1.0). Extracting a large number of rigid modes for calculation of the dynamic response may be conservative in the case of Spectrum analysis, since all spectral modal combination methods (SRSS, GROUP, ABS, etc.) give conservative results versus the algebraic combination method (always used during time history analysis), which gives a more realistic representation of the net response of the rigid modes. Based upon the response spectrum shown in the following figure, an appropriate cutoff point for the modal extraction would be about 33 Hz. Non-conservative cutoff (Misses amplification of any modes in resonant range) Conservative cutoff (Multiplies missing mass contribution by excessive DLF—1.6) Optimal cutoff (Includes all modes in resonant range, uses low DLF—1.05—for missing mass contribution, minimizes combination of rigid modes) Conservative Cutoff (Too many rigid modes combined using non-conservative summation methods)

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When the analysis type is SPECTRUM, MODES, or TIMEHIST, either this parameter or the previous one must be entered.

Closely Spaced Mode Criteria/Time History Time Step (ms) (Active for: Spectrum/GROUP and Time History) This parameter does double duty, depending upon the analysis type. For a Spectrum analysis type with GROUP modal Combination Method (as defined by USNRC Regulatory Guide 1.92), this parameter specifies the frequency spacing defining each modal group—i.e., the percent (of the base frequency) between the lowest and highest frequency of the group. Regulatory Guide 1.92 specifies the group spacing criteria as 10% (entered here as 0.1), so it is unlikely that the user would ever wish to change the Closely Spaced Mode Criteria from the CAESAR II default value of 0.1. The GROUP modal combination method is described in detail in the section Modal Combination Method found later in this chapter. For a Time History analysis type, this parameter is used to enter the length of the time slice, in milliseconds, to be used by the program during its step-by-step integration of the equations of motion for each of the extracted modes (CAESAR II uses the unconditionally stable Wilson q integration method, so any size time step will provide a solution, with a smaller step providing greater accuracy—and more strain on computational resources). The time step should be sufficiently small that it can accurately map the force vs. time load profile (i.e., the time step should be smaller than typical force ramp times). Additionally, the time step must be small enough that the contribution of the higher order modes is not filtered from the response. For this reason, it is recommended that the time step should be selected such that Time Step (in seconds) times Maximum Modal Frequency (in Hz) be less than 0.1. For example, if the modal frequency cutoff is set to 50 Hz, the time step should be set to a maximum of 2 milliseconds: 0.002 sec x 50 Hz = 0.1

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Load Duration (Time History or DSRSS Method) (Sec.) (Active for: Spectrum/DSRSS and Time History) This parameter is used to specify the duration of the applied dynamic load. For a Time History analysis, this parameter is used to specify the total length of time (in seconds) over which the dynamic response is to be simulated. The load duration, divided by the time step size (see the previous section) gives the total number of integration steps making up the solution (currently CAESAR II limits the number of time steps to 5000, or as permitted by available memory and system size). It is recommended that, if possible, the duration be at least equal to the maximum duration of the applied load, plus the period (in seconds) of the first extracted mode. This allows simulation of the system response throughout the imposition of the external load, plus one full cycle of the resulting free vibration. After this point, the response will die out, according to the damping value used. For example, if the applied load is expected to last 150 milliseconds, and the lowest extracted frequency is 3 hz, the load duration should be set to a minimum of 0.150 plus 1/3, or 0.483 seconds. For a Spectrum analysis using the Double Sum (DSRSS) modal Combination Method (as defined by USNRC Regulatory Guide 1.92), this parameter is used to specify the duration of the earthquake, in seconds. This duration is used to compute the modal correlation coefficients based on empirical data. The DSRSS modal combination method is described in detail in the section Modal Combination Method later in this chapter.

Damping (Time History or DSRSS) (Ratio of Critical) (Active for: Spectrum/DSRSS, Harmonics, and Time History) This parameter is used to specify the system damping value, as a ratio of critical damping. Typical values for piping systems, as recommended in USNRC Regulatory Guide 1.61 and ASME Code Case N-411, range from 0.01 to 0.05, based upon pipe size, earthquake severity, and the system’s natural frequencies. Generally, damping cannot be considered in the mathematical solutions required for spectrum or harmonic analysis. It is therefore ignored (or solved as specialized cases) in most analyses, and must be instead considered through adjustment of the applied loads (generation of the response spectrum) and/or system stiffness. For a Time History analysis, damping is used explicitly, since this method uses a numeric solution to integrate the dynamic equations of motion. For a Spectrum analysis using the Double Sum (DSRSS) modal Combination Method (as defined by USNRC Regulatory Guide 1.92), the damping value is used in the computation of the modal correlation coefficients. (Note that CAESAR II does not permit the specification of damping values for individual modes.) The DSRSS modal combination method is described in detail in the section Modal Combination Method later in this chapter. For a Harmonic analysis, this ratio is converted to Rayleigh Damping, where the damping matrix can be expressed as multiples of the mass and stiffness matrices: [C] = a [M] + b [K]

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On a modal basis, the relationship between the ratio of critical damping Cc and the constants a and b is given as:

Where: = undamped natural frequency of mode (radians/sec) For many practical problems, a is extremely small, and so may be ignored, reducing the relationships to: =0

= 2 Cc /

CAESAR II uses this implementation of damping for its harmonic analysis, with the exception that a single b is calculated for the multi-degree-of-freedom system, and the w used is that of the load forcing frequency. When the forcing frequency is in the vicinity of a modal frequency, this gives an accurate estimate of the true damping value.

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ZPA (Reg. Guide 1.60/UBC- G's)/# Time History Output Cases (Active for: Spectrum/1.60/UBC and Time History) This parameter does double duty, depending upon the analysis type. When used with certain pre-defined normalized response spectra, it is used as the acceleration factor (in g's) by which the spectrum is scaled. For example, when a spectrum analysis uses one of the pre-defined spectra names beginning with "1.60" (i.e., 1.60H.5 or 1.60V7), CAESAR II constructs an earthquake spectrum according to the instructions given in USAEC (now USNRC) Regulatory Guide 1.60. That guide requires that the shape of the response spectrum be chosen from the curves shown in the following figures, based upon the system damping value (for example, the .5 or 7 in the spectrum names 1.60H.5 or 1.60V7). If the analysis uses one of the predefined spectra names beginning with "UBC" (i.e., UBCSOIL1), CAESAR II uses the normalized seismic response spectra for the corresponding soil type from Table 23-3 from the Uniform Building Code (1991 Edition). Both the Reg Guide 1.60 and the UBC curves are normalized to represent a ground acceleration (ZPA) of lg; the true value is actually site dependent. Therefore, entering ZPA value here appropriately scales any Regulatory Guide 1.60 or the Uniform Building Code response spectra.

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When performing Time History analysis, this parameter is used to specify the number of distinct times at which the results of the load cases (the dynamic load as well as all static/dynamic combinations) should be generated. In addition, CAESAR II generates one set of results (for each load case) containing the maximum of each output value (displacement, force, stress, etc.) along with the time at which it occurred. The times for which results are generated are determined by dividing as evenly as possible the load duration by the number of output times—for example, if the load duration is 1 second, and 5 output cases are requested, results will be available at 200, 400, 600, 800, and 1000 milliseconds (in addition to the maximum case). The total number of results cases generated for an analysis is the product of the number of load cases (one dynamic case plus the number of static/dynamic combination cases) times the number of results cases per load (one maxima case plus the requested number of output cases). Currently the total number of results cases is limited to 99: (1 + # Static/Dynamic Combinations) x (1 + # Output Cases) <= 99 At least one output case (in addition to the automatically generated maxima case) must be requested; more than one is not really necessary, since the worst case results are reflected in the Maxima case and individual results at every time step are available through the ELEMENT command when animating the Time History results.

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Re-use Last Eigensolution (Active for: Spectrum and Time History) When repeating a dynamic analysis, this parameter may be set to “Yes,” causing CAESAR II to skip the eigensolution (reusing the results of the earlier analysis), and only perform the computations for displacements, reactions, forces, and stresses. Activating this option is only valid after an initial eigensolution has been performed and is still available. Additionally, the mass and stiffness parameters of the model must be unchanged or the previous eigensolution is invalid.

Spatial or Modal Combination First (Active for: Spectrum) This directive tells CAESAR II whether to combine the Spatial components or the Modal components of the load case first. When performing a spectrum analysis, each of the modal responses must be summed. In addition, if multiple shocks have been applied to the structure in more than one direction, the results from different directions must be combined—for example, spatially combining the X-direction, Y-direction, and Zdirection results. The question arises as to whether the spatial summations should precede or follow the modal summations. A difference in the final results (of Spatial first vs. Modal first) arises whenever different methods are used for the spatial and modal combinations. The combination of Spatial components first implies that the shock loads are dependent, while the combination of Modal components first implies that the shock loads are independent. Dependent and Independent refer to the time relationship between the X, Y, and Z components of the earthquake. With a dependent shock case, the X, Y, and Z components of the earthquake have a direct relationship—a change in the shock along one direction produces a corresponding change in the other directions. For example, this would be the case when the earthquake acts along a specific direction having components in more than one axis—such as when a fault runs at a 30° angle between the X- and Z-axes. In this case, the Z-direction load would be a scaled (by a factor of tan 30°), but otherwise identical version of the X-direction load. In this case, spatial combinations should be made first. An Independent shock is one where the X, Y, and Z time histories produce related frequency spectra but have completely unrelated time histories. It is the Independent type of earthquake that is far more common, and thus in most cases the modal components should be combined first. For example, IEEE 344-1975 (IEEE Recommended Practices for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations) states: “Earthquakes produce random ground motions which are characterized by simultaneous but statistically INDEPENDENT horizontal and vertical components.”

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This is usually less of an issue for force spectrum combinations, since normally there are no separate spatial components to combine—i.e., there are not X-, Y-, and Z-shocks acting simultaneously. However, in the event that there is more than one potential force load (such as when there is a bank of relief valves that can fire individually or in combination), the spatial combination method may be used to indicate the independence of the loadings. For example, if two relief valves may or may not fire simultaneously (i.e., they are independent), the two shocks should be defined as being in different directions (for example, Xand Y-), and the combination method selected should be “Modal before Spatial.” If under certain circumstances, the two valves will definitely open simultaneously (i.e., the loadings are dependent), the combination method should be “Spatial before Modal”. (Otherwise, the direction defined for a force spectrum loading has no particular meaning.) Nuclear Regulatory Guide 1.92 (published in February, 1976) describes the requirements for combining spatial components when performing seismic response spectra analysis for nuclear power plants. Note: Since all Time History combinations are done algebraically (in-phase) this parameter has no effect on Time History results.

Spatial Combination Method (SRSS/ABS) (Active for: Spectrum) This parameter is used to define the method for combining the spatial contributions of the shocks in a single spectrum load case. This option is only used for spectrum runs with more than a single excitation direction. Since directional forces are usually combined vectorially, this points to a Square Root of the Sum of the Squares (SRSS) combination method as being most appropriate. An Absolute method is provided for additional conservatism. Note: Since all Time History combinations are done algebraically (in-phase) this parameter has no effect on Time History results.

Modal Combination Method (GROUP/10%/DSRSS/ABS/SRSS) (Active for: Spectrum) During a spectrum analysis, responses are calculated for each of the individual modes; these individual responses are then combined to get the total system response. Considering that the response spectrum yields the maximum response at any time during the course of the applied load, and considering that each of the modes of vibration will probably have different frequencies, it is probable that the peak responses of all modes will not occur simultaneously. Therefore an appropriate means of summing the modal responses must be considered. Nuclear Regulatory Guide 1.92 (published in February, 1976) defines the requirements for combining modal responses when performing seismic response spectra analysis for nuclear power plants. The four options presented there are also available, along with one other, for modal combinations under nonnuclear seismic and force spectrum analyses. There are five available modal combination methods: Grouping Method Ten Percent Method Double Sum Method Absolute

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Square Root of the Sum of the Squares

Grouping Method This method is defined in USNRC Regulatory Guide 1.92. The Grouping Method attempts to eliminate the drawbacks of the Absolute and SRSS methods (see below) by assuming that modes are completely correlated with any modes with similar (closely spaced) frequencies, and are completely uncorrelated with those modes with widely different frequencies. Therefore, the total system response is calculated as

R=

N

! k =1

1/ 2

Rk 2 +

P q =1 +

j l =i

j m =i

+

Rlq Rmq

"

(where 1 m)

Where: R = total system response of the element N = number of significant modes considered in the modal response combination Rk = the peak value of the response of the element due to the kth mode P = number of groups of closely-spaced modes (where modes are considered to be closely-spaced if their frequencies are within 10% of that of the base mode in the group), excluding individual separated modes. No mode can be in more than one group. i = number of first mode in group q j = number of last mode in group q Rlq = response of mode l in group q Rmq = response of mode m in group q Effectively, this method dictates that the responses of any modes which have frequencies within 10% of each other first be added together absolutely, with the results of each of these groups then combined with the remaining individual modal results using the SRSS method. Note: The 10% figure controlling the definition of a group may be changed by using the Closely Spaced Mode Criteria/Time History Time Step (ms) parameter. For more information see the corresponding section earlier in this chapter.

Ten Percent Method This method is defined in the USNRC Regulatory Guide 1.92. The Ten Percent Method is similar to the Grouping method in that it assumes that modes are completely correlated with any modes with similar (closely spaced) frequencies, and are completely uncorrelated with those modes with widely different frequencies. The differences between this one and the preceding method is that the Grouping Method assumes that modes are only correlated with those that fall within the group -i.e., are within a 10% band, while this method assumes that modes are correlated with those that fall within 10% of the subject modeeffectively creating a 20% band - 105 up and approximately 10% down. The total system response is calculated as R=

N

! k =1

1/ 2

Rk 2 + 2

Ri R j

"

(Where i

j)

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Where: Ri, Rj = the peak value of the response of the element due to the ith and jth mode, respectively, where mode i and j are any frequencies within 10% of the each other, Where: (fi, fj) / fi = frequencies of modes i and j, respectively

Note: The 10% figure controlling the definition of closely spaced frequencies may be changed by using the Closely Spaced Mode Criteria/Time History Time Step (ms) parameter. (See description in corresponding section earlier in this chapter).

Double Sum Method (DSRSS) This method is also defined in USNRC Regulatory Guide 1.92. This combination method is the most technically correct for earthquake loads, in that an attempt is made to estimate the actual intermodal correlation coefficient based upon empirical data. The total system response is calculated as Where: Rs =

the peak value of the response of the element due to mode s

eks =

intermodal correlation coefficient

=

[ 1 + {(

'-

') /(ßk'

k

s

' =

k

[ 1 - ßk2 ]1/2

' =

s

[ 1 - ßs2 ]1/2

k

s

ßk' =

ßk + 2 / ( td

k

)

ßs' =

ßs + 2 / ( td

s

)

k

+ ßs'

k

=

frequency of mode k, rad/sec

s

=

frequency of mode s, rad/sec

)}2 ]-1

s

ßk =

ratio of damping to critical damping of mode k, dimensionless

ßs =

ratio of damping to critical damping of mode s, dimensionless

td

=

duration of earthquake, sec

Note: The load duration (td) and the damping ratio (ß) may be specified by using the Load Duration (Time History or DSRSS method) (sec.) and Damping (Time History or DSRSS) (ratio of critical) parameters described in the corresponding sections found earlier in this chapter.

Absolute Method This method states that the total system response is equal to the sum of the absolute values of the individual modal responses. (This is effectively the same as using the DSRSS method with all correlation coefficients equal to 1.0, or the Grouping method, with all modes being closely spaced.) The total system response is calculated as:

R=

N i =1

Ri

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This method gives the most conservative result, since it assumes that the all maximum modal responses occur at exactly the same time during the course of the applied load. This is usually overly-conservative, since modes with different natural frequencies will probably experience their maximum DLF at different times during the load profile.

Square Root of the Sum of the Squares (SRSS) This method states that the total system response is equal to the square root of the sum of the squares of the individual modal responses. (This is effectively the same as using the DSRSS method with all correlation coefficients equal to 0.0, or the Grouping method, with none of the modes being closely spaced.) The total system response is calculated as:

R=

N

! i =1

1/ 2

Ri2

"

This method is based upon the statistical assumption that all modal responses are completely independent, with the maxima following a relatively uniform distribution throughout the duration of the applied load. This is usually non-conservative, especially if there are any modes with very close frequencies, since those modes will probably experience their maximum DLF at approximately the same time during the load profile. Note: Since all Time History combinations are done algebraically (in-phase) this parameter has no effect on Time History results.

Include Pseudostatic (Anchor Movement) Components (Y/N) (Active for: Spectrum/ISM) This option is only used when Independent Support Motion (anchor movement) components are part of a shock load case. The excitation of a group of supports produces both a dynamic response and a static response. The static response is due to the movement of one group of supports or anchors relative to another group of supports/anchors. These static components of the dynamic shock loads are called “pseudostatic components.” USNRC recommendations, as of August 1985, suggest that the following procedure be followed for pseudostatic components: 1

For each support group, the maximum absolute response should be calculated for each input direction.

2

Same direction responses should then be combined using the absolute sum method.

3

Combination of the directional responses should be done using the SRSS method.

4

he total response should be formed by combining the dynamic and pseudostatic responses, using the SRSS method.

Therefore pseudostatic components should be included whenever Independent Support spectral loadings are used.

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Include Missing Mass Components (Y/N) (Active for: Spectrum and Time History) During spectrum (either seismic or force spectrum) or time history analyses, the response of a system under a dynamic load is determined by superposition of modal results. One of the advantages of this type of modal analysis is that usually only a limited number of modes are excited and need to be included in the analysis. The drawback to this method is that although displacements may be obtained with good accuracy using only a few of the lowest frequency modes, the force, reaction, and stress results may require extraction of far more modes (possibly far into the rigid range) before acceptable accuracy is attained. CAESAR II provides a feature, called the “Missing Mass Correction,” which helps solve these problems. This feature offers the ability to include a correction which represents the contribution of the higher order modes not explicitly extracted for the modal/dynamic response, thus providing greater accuracy without additional calculation time. When this option is activated (by entering Yes for this parameter), the program automatically calculates the net (in-phase) contribution of all non-extracted modes and combines it with the modal contributions—avoiding the long calculation time associated with the extraction of the high order modes and the possible excessive conservatives of the summation methods. This feature is described in Chapter 6 of this manual.

Pseudostatic (Anchor Movement) Comb. Method (SRSS/ABS) (Active for: Spectrum) This directive specifies the method by which the pseudostatic responses (see description in the earlier section Include Pseudostatic (Anchor Movement) Components (see "Include Pseudostatic (Anchor Movement) Components (Y/N)" on page 77)) are to be combined with the dynamic (inertial) responses; therefore it is applicable only when there is at least one Independent Support Motion excitation component in a shock load case. Pseudostatic combinations are done after all directional, spatial, and modal combinations. Absolute combination gives conservative results, but, as noted in the section Include Pseudostatic (Anchor Movement) Components, the USNRC recommends using the SRSS method for pseudostatic combinations.

Missing Mass Combination Method (SRSS/ABS) (Active for: Spectrum) This directive defines the method used to combine the missing mass/force correction components (see description in an earlier section, Include Missing Mass Components (see "Include Missing Mass Components (Y/N)" on page 78)) with the modal (dynamic) results. Research suggests that the modal and rigid portions of the response are statistically independent, so the SRSS combination method (CAESAR II’s default) is usually most accurate. The Absolute combination method provides a more conservative result, based upon the assumption that the modal maxima occur simultaneously with the maximum ground acceleration. Missing mass components are combined following the modal combination. Note: Even though missing mass components may be included during Time History analyses, all Time History combinations are done algebraically (in-phase), so this parameter has no effect on Time History results.

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Directional Combination Method (SRSS/ABS) (Active for: Spectrum) This directive specifies the method used for combining shock components acting in the same direction. This directive is used most typically with Independent Support Motion load cases, where it defines the way in which responses from different support groups caused by excitation in the same direction are combined. Additionally, if there are multiple uniform shock spectra acting in the same direction (although this is unusual), this directive would govern their combination. In general, directional combinations should be made using the absolute method. (As noted in the earlier section, Include Pseudostatic (Anchor Movement) Components (see "Include Pseudostatic (Anchor Movement) Components (Y/N)" on page 77), this is the USNRC recommendation for directional combination of pseudostatic responses.) However, in the case of force spectrum loads, if several loads (for example, several relief valve loads) are all defined with the same “shock direction”, using an SRSS combination method would be a way of modeling these as independent loads, while using the Absolute method would model them as dependent loads. Note: Since all Time History combinations are done algebraically (in-phase) this parameter has no effect on Time History results.

Sturm Sequence Check on Computed Eigenvalues (Y/N) (Active for: Spectrum, Modal, and Time History) In almost all cases, the eigensolver will detect modal frequencies from the lowest frequency to the highest. Sometimes, when there is some strong directional dependency in the system, the modes may converge in the wrong order. This could cause a problem if the eigensolver reaches the cutoff number of modes (i.e., 20), but has not yet found the 20 modes with the lowest frequency (it may have found modes 1 through 18, 20, and 21, and would have found number 19 next). CAESAR II checks for this anomaly using the Sturm Sequence calculation. This procedure determines the number of modes that should have been found between the highest and lowest frequencies found, and compares that against the actual number of modes extracted. If those numbers are different, the user is given a warning. For example, if 22 natural frequencies are extracted for a particular system, and if the highest natural frequency is 33.5 Hz, the Sturm Sequence check makes sure that there are exactly 22 natural frequencies in the model between zero and 33.5+p Hz, where p is a numerical tolerance found from:

p=

10Log10 [(Highest Eigenvalue)-(Number of Significant Figures+1.5)] 2n

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The Sturm Sequence check would fail in the case where there are two identical frequencies at the last frequency extracted. The significance of this failure can only be estimated by the user. For example, consider a system with the following natural frequencies: 0.6637

1.2355

1.5988

4.5667

4.5667

If the user asks for only the first four natural frequencies, a Sturm Sequence failure would occur because there are five frequencies, rather than four, which exist in the range between 0.0 and 4.5667 + p (where p calculates to 0.0041). To correct this problem, the user can do either of the following: Increase the frequency cutoff by the number of frequencies not found. (This number is reported by the Sturm Sequence Check.) Increase the cutoff frequency some small amount, if the frequency cutoff terminated the eigensolution. This will usually allow the lost modes to fall into the solution frequency range. Fix the subface size at 10 and rerun the job. Increasing the number of approximation vectors improves the possibility that at least one of them will contain some component of the missing modes, allowing the vector to properly converge. The default here is “Yes,” and should be left alone unless the user has some specific reason for deactivating the check.

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Advanced Parameters

Estimated Number of Significant Figures in Eigenvalues (Active for: Spectrum, Modal, and Time History) This is the approximate number of significant figures in the computed eigenvalues ( 2, where is the angular frequency in rad/sec). For example, using the default value of 6, if a computed eigenvalue was 44032.32383, then the first digit to the right of the decimal is probably the last accurately computed figure. The eigenvectors, or mode shapes, are computed to half as many significant figures as are the eigenvalues. If the eigenvalues have 6 significant figures of accuracy, then the eigenvectors have 3. This number should typically never be decreased. Increases to 8 or 10 are not unusual but result in slower solutions with typically little change in response results.

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Jacobi Sweep Tolerance (Active for: Spectrum, Modal, and Time History) Eigen analyses are done using an NxN subspace for calculating the natural frequencies and mode shapes for a reduced problem. The first step is to perform a Jacobi denationalization of the subspace. Iterations are performed until the off-diagonal terms of the matrix are approximately zero. The off-diagonal terms are considered to be close enough to zero when their ratio to the on-diagonal term in the row is smaller the Jacobi Sweep Tolerance. The default is 1.0E-12. Users wishing to change this value should be aware of the computer’s precision (the IEEE-488 double precision word on the IBM PC has approximately 14 significant figures) and the approximate size of the on-diagonal coefficients in the stiffness matrix for the problem to be solved (which may be estimated from simple beam expressions).

Decomposition Singularity Tolerance (Active for: Spectrum, Modal, and Time History) During the eigensolver’s decomposition of what may be a shifted stiffness matrix, a singularity check is performed to make sure that the shift is not too close to an eigenvalue that is to be calculated. If a singular condition is detected, a new shift, not quite as aggressive as the last one, is computed and a new decomposition is attempted. If the new composition fails, a fatal error is reported from the eigensolver. In certain cases, increasing the singularity tolerance is warranted and eliminates this fatal error. Values should not be entered greater than 1.0 E13. Singularity problems may also exist when very light, small diameter piping is attached to very heavy, large diameter, or when very, very short lengths of pipe are adjacent to very, very long lengths of pipe.

Subspace Size (0-Not Used) (Active for: Spectrum, Modal, and Time History) During an eigensolution, the NDOFxNDOF problem constructed by the user is reduced to an NxN problem during each subspace iteration, where N is the subspace size. If a zero is entered in this field, CAESAR II selects what is expected to be an optimal subspace size (so this value usually need not be changed); if a non-zero value is entered here, it will override CAESAR II’s calculation and will be used as the subspace size. CAESAR II’s default is to use the square root of the bandwidth (with a minimum of 4) as the subspace size, resulting in sizes of 4 to 8 for typical piping configurations. Increasing the subspace size slows the eigensolution, but increases the numerical stability. Values in the range between 12 and 15 should probably be used when unusual geometries or dynamic properties are encountered, or when a job is large (has 100 elements or more, and/or requires that 25 or more frequencies be extracted).

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No. to Converge Before Shift Allowed (0 - Not Used) (Active for: Spectrum, Modal, and Time History) A zero in this field lets CAESAR II select what it thinks will be the most optimal shifting strategy for the eigen problem to be solved. One way to speed the eigensolution is to improve the convergence characteristics. The convergence rate for the lowest eigenpair in the subspace is inversely proportional to 1/ 2, where 1 is the lowest eigenvalue in the current subspace and 2 is the next lowest eigenvalue in the current subspace. A slow convergence rate is represented by an eigenvalue ratio of approximately one, and a fast convergence rate is represented by an eigenvalue ratio of zero. The shift is employed to get the convergence rate as close to zero as possible. The cost of each shift is one decomposition of the system set of equations. The typical shift value is equal to the last computed eigenvalue plus 90 percent of the difference between this value and the lowest estimated eigenvalue still nonconverged in the subspace. As 1 is shifted closer to zero, the ratio 1/ 2 will become increasingly smaller thus increasing the convergence rate. In certain instances where eigenvalues are very closely spaced, shifting can result in eigenvalues being lost (the Sturm Sequence Check will detect this condition). A large value entered for this parameter will effectively disable shifting, so no eigenvalues will be missed; however, the solution will take longer to run. When the system to be analyzed is very large, shifting the set of equations can be very time consuming—in these cases, the user is advised to set this parameter to somewhere between 4 and 8.

No. of Iterations Per Shift (0 - Pgm computed) (Active for: Spectrum, Modal, and Time History) A zero in this field lets CAESAR II compute what it thinks is an optimal number of subspace iterations per shift. This parameter, along with the next one (% of iterations per shift before orthogonalization) can work together to control solution shifting. These two parameters are used to limit the number of Gram-Schmidt orthogonalizations that are performed. Trying to limit this number is very dangerous for small subspace problems, but less dangerous when the subspace size is large (around 10-20 percent of the total number of eigenpairs required). The Gram-Schmidt orthogonalization is by default performed once during each subspace iteration. This orthogonalization makes sure that the eigenvector subspace does not converge to an already found eigenpair. When a large number of eigenpairs are to be computed this repeated computation can appreciably slow down the extraction of the highest eigenpairs. Proper setting of these parameters can cause the eigensolution to perform the orthogonalization every second, third, fourth, etc. iteration, thus speeding the solution. Unfortunately, once orthogonalized, the subspace may still converge to earlier eigenpairs during subsequent “non-orthogonalized” subspace iteration passes. Users setting these parameters are urged to use caution. The Force Orthogonalization After Convergence (see "Force Orthogonalization After Convergence (Y/N)" on page 84) parameter (see corresponding section later in this chapter) should probably also be set if the frequency of orthogonalization is slowed.

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Percent of Iterations Per Shift Before Orthogonalization (Active for: Spectrum, Modal, and Time History) CAESAR II computes a number of iterations per shift that are to be performed, which the user can alter if desired. A maximum of N eigenpairs can conceivably converge per subspace pass, where N is the subspace size (although this is highly unlikely). By default a Gram-Schmidt orthogonalization is performed for each subspace pass. This directive allows the user to alter this default. For example, if there are 12 iterations per shift, and the percentage of iterations per shift is 50 percent (an entry of 0.50), the Gram-Schmidt orthogonalization would be performed every 6 iterations. Users employing this option should also set the Force Orthogonalization After Convergence (see "Force Orthogonalization After Convergence (Y/N)" on page 84) directive to “Yes”. The Percent of Iterations per Shift Before Orthogonalization parameter is most often used in conjunction with the No. of Iterations per Shift (see "No. of Iterations Per Shift (0 - Pgm computed)" on page 83) parameter because then the user knows exactly how many iterations will go by without an orthogonalization.

Force Orthogonalization After Convergence (Y/N) (Active for: Spectrum, Modal, and Time History) This parameter is only needed for eigensolutions for which the Percent of Iterations per Shift Before Orthogonalization (on page 84) (the previous section) has been set to a non-zero value. When set to “Yes” in this case, whenever a subspace pass that sees at least one eigenpair convergence completes, a Gram-Schmidt orthogonalization is performed whether the specified percentage of iterations has been completed or not.

Use Out-Of-Core Eigensolver (Y/N) (Active for: Spectrum, Modal, and Time History) This parameter is used primarily as a benchmarking and debugging aid. When entered as “Yes”, the outof-core eigensolver is automatically invoked regardless of the problem size. Using this solver can take considerably more time than the in-core solver, but should in all cases produce exactly the same results. Note that if the problem is too big to fit into the in-core solver (the capacity of which is based upon the amount of available extended memory), the out-of-core solver will be invoked automatically—this parameter does not need to be changed to have this automatic switch occur when necessary.

Frequency Array Spaces (Active for: Spectrum, Modal, and Time History) This is the maximum number of eigenpairs that can be extracted for the problem. The default value of 100 is arbitrary. If the user needs to extract more than 100 eigenpairs, then some number greater than the number to be extracted must be entered.

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Pulsation Loads Unexpectedly, and sometimes after support changes or process modifications, an operating line will begin experiencing large amplitude, low frequency vibration. The first step in the solution is the construction of the dynamic model. Particular attention should be paid when modeling the piping system in the area of the field vibration. This might include accurately representing valve operators, in-line flange pairs, orifice plates and measuring equipment. It is also a good idea to add extra nodes in the area where vibration is experienced. The extra nodes would be put at bend “near” nodes and at span midpoints. The next step is the eigenvalue/eigenvector extraction. If the system is large, then degrees of freedom far removed from the area of local vibration should be eliminated. (6-10) natural frequencies should be extracted. Natural frequencies and mode shapes define the systems “tendency to vibrate.” The mode shapes extracted should show how the system in the area of the local vibration problem is tending to displace. In most cases acoustic resonances are coupled with mechanical resonances to produce the large amplitude vibrations experienced in the field. Very typically one of the first mode shapes will show exactly the shape displayed by the pipe vibrating in the field. If the mode shapes extracted do not show movement in the area of the local vibration, then not enough degrees of freedom were removed from other areas. If the lowest mode shape in the area of the local vibration problem is above (15) Hz. then there is a good possibility that either the vibration is mechanically induced or the fluid pulsation peak pressures are very high. Either of these cases may represent critical situations which should be evaluated by an expert. When the mode shape is identified which corresponds to the observed field vibration, the pulsation load model can be developed. Pulsation loads will exist at closed ends, at bends, and at changes in diameter. Harmonically varying forces are put at these points in an attempt to get the mathematical model to vibrate like the real piping system. The driving frequency for the applied harmonic load should be equal to the frequency that pressure pulses are introduced into the line. The magnitude of the harmonic load can be estimated within a range of tolerances. The actual design value is selected from this range such that resulting displacements of the model are close to those observed in the field. Output from the harmonic analysis can be processed in the static output processor and maximum restraint loads due to the dynamic forces calculated. It is critical when redesigning supports for dynamic loads that static thermal criteria are not violated by any new support configuration designed. Important: Static thermal criteria and dynamic displacement criteria must be satisfied simultaneously. The ultimate objective of the harmonic analysis will be to find the elbow pair whose unbalanced load results in the observed field vibration. Unbalanced loads exist between adjacent elbows because the pressure peak in the traveling wave hits each elbow at a slightly different time.

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If the pressure at elbow “a” is denoted by Pa(t) and the pressure at elbow “b” is denoted by Pb(t), then the unbalanced force which acts along the pipe connecting the two elbows is: F = A * Pa(t) - A * Pb(t)

EQ. (1)

Where A is the inside area of the pipe. The expression for Pa(t) can be found assuming the pressure peak hits the elbow “a” at time t = 0: Pa(t) = Pavg + 0.5 (dP) cos t

EQ. (2)

Where: (Pavg) - average pressure in the line, (dP)

- alternating component of the pressure, (Pmax-Pmin)

( )

- driving frequency.

If the straight pipe between the elbows “a” and “b” is (L) inches long, then the pressure peak that has just passed elbow “a” will get to elbow “b” (ts) seconds later, where (ts) = (L) / c, (c) being the speed of sound in the fluid. (Remember, pressure pulses travel at the speed of sound, not the speed of the fluid ! ! !) The expression for the pressure at “b” can now be written: Pb(t) = Pavg + 0.5(dP) cos ( t + Q)

EQ.(3)

Q is the phase shift between the pressure peaks at “a” and “b”, Q=

* (ts). (Where Q is in radians, and

is in radians/second)

Combining equations 1, 2, and 3 the unbalanced pressure force can be written: F(t) = 0.5(dP)A * [ cos t - cos ( t-Q) ] This function has a maximum: Fmax = 0.5(dP)A sin Q/cos (Q/2) and a period of 1/w, and will be approximated with: f(t) = 0.5(dP)A (sin Q/cos (Q/2)) cos t The formulation of the harmonic loads can be summarized as follows: 1

Decide which elbow-elbow pair is most likely to have an unbalanced force which could cause the displacements observed in the field.

2

Find upper and lower estimates for the following variables: dP — Alternating pressure in the line (Pmax - Pmin) — Driving frequency. c — Speed of sound in the fluid. L — Length between the two elbows. A — Area of the pipe.

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3. Find the time it takes the pressure wave to get from one elbow to the other. ts = L / (c-) (c-) is the lower estimate for the speed of sound in the fluid. 4. Find the largest estimated magnitude of the unbalanced pressure force: Fmax = (0.5) (dP+)A * sin [( +) (ts)] / cos [( t) (ts)/2] (dP+) is the upper estimate for the alternating pressure. ( +) is the upper estimate for the driving frequency. 5. Run a single harmonic analysis with a force of F = Fmax [cos ( t)] acting along the axis of the pipe between the two elbows. If the pattern of the displacement approximately that seen in the field, and if the magnitude of the calculated displacement is greater than or equal to the magnitude of the displacement in the field, then the harmonic load to be used for the design of the new restraints has been found.

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Relief Valve Thrust Load Analysis There can be two types of destructive dynamic forces associated with relief devices: Thrust at the valve/atmosphere interface Acoustic shock due to the sudden change in fluid momentum and the associated traveling pressure wave(s). The analyst must evaluate the effective contribution of both types of loads. Dynamic forces associated with relieving devices can cause considerable mechanical damage to equipment and supports. The discussion below concerns only the thrust at the valve/atmosphere interface. The acoustic traveling pressure wave can be dealt with similar to the water hammer problem, addressed elsewhere. The first step in performing a relief load analysis is to compute the magnitudes of the relieving thrust forces. For open-type vent systems CAESAR II has a RELIEF LOAD SYNTHESIZER that will make these computations automatically for the user. There are two procedures incorporated into the synthesizer, one is for gases greater than 15 psig, and the other is for liquids. Both are discussed as follows.

Relief Load Synthesis for Gases Greater Than 15 psig CAESAR II assumes that a successful vent stack/relief system design maintains the following gas properties:

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The input for the gas relief load synthesis is shown as follows:

Line Temperature Enter the stagnation condition temperature of the gas to be relieved. (Usually just the gas temperature upstream of the relief valve.)

Line Pressure Enter the stagnation pressure of the gas to be relieved. (Usually just the gas pressure upstream of the relief valve.) Note that stagnation properties can vary considerably from line properties if the gas flow velocity in the line is high.

ID of Relief Valve Orifice Enter the flow passage inside diameter for the smallest diameter in the relief valve throat. (This information is usually provided by the relief valve manufacturer).

ID of Relief Valve Piping Enter the inside diameter of the piping attached directly to the exhaust of the relief valve.

ID of Vent Stack Piping If CAESAR II is to size the vent stack then leave this ID blank. If the vent stack piping is the same size as the relief valve piping, i.e. it is one-in-the-same, then this field may be left blank. Otherwise enter the inside diameter of the vent stack piping.

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Length of the Vent Stack Enter the length of the vent stack. This is a required entry. Add double the lengths of fittings and elbows (or compute the appropriate equivalent lengths for non-pipe fittings and add the lengths). Some typical values for these constants are given below: Ratio of Gas-Specific Heats

(k)

Gas Constant (R)

(ft. lbf./lbm./deg. R

Superheated Steam

1.300

Nitrogen

55.16

Saturated Steam

1.100

Carbon Dioxide

35.11

Nitrogen

1.399

Acetylene

59.35

Carbon Dioxide

1.288

Ammonia

90.73

Acetylene

1.232

n-Butane

26.59

Ammonia

1.304

Ethane

51.39

n-Butane

1.093

Ethylene

55.09

Ethane

1.187

Methane

96.33

Ethylene

1.240

Propane

35.05

Methane

1.226

Propane

1.127

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Does the Vent Pipe Have an Umbrella Fitting (Y/N) Enter a Y or a N. See the following figures to determine if the connection of the vent stack to the vent piping is via an umbrella fitting.

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Should CAESAR II Size the Vent Stack (Y/N) Enter a Y if CAESAR II should size the vent stack. The sizing algorithm searches through a table of available inside pipe diameters starting at the smallest diameter until a vent stack ID is found that satisfies the thermodynamic criteria shown in the figure above. The computed ID is automatically inserted into the input. Example input and output from the relief load synthesizer is shown and discussed as follows:

Relief Load Synthesis Input (Gas)

Relief Load Synthesis Output (Gas)

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Computed Mass Flowrate (Vent Gas) This is CAESAR II’s computed gas mass flow rate based on choked conditions at the relief orifice. If greater mass flow rates are expected, then the error in either the approach used by CAESAR II or in the expected mass flow rate should be investigated.

Thrust at Valve Pipe/Vent Pipe Interface If there is an umbrella fitting between the vent stack and the relief valve piping then this is the thrust load that acts back on the relief valve piping. (See the following figure.) If the vent stack is hard piped to the relief valve piping then this intermediate thrust will be balanced by tensile loads in the pipe and can be ignored.

Thrust load acts directly on valve opening.

Only the valve pipe/vent stack interface thrust acts in this configuration.

Thrust at the Vent Pipe Exit When there is an elbow in the vent stack piping, this is the thrust load that acts on the elbow just before the pipe opening into the atmosphere. (See the following figures for clarification.)

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Transient Pressure Rise on Valve Opening This is the estimated magnitude of the negative pressure wave that will be superimposed on the line pressure when the relief valve fist opens. This negative pressure wave will move back through the relief system piping similar to the pressure wave in the downstream piping of a water hammer type system. The magnitude of this wave is estimated as (Po-Pa)*Ap, where Po is the stagnation pressure at the source, Pa is atmospheric pressure, and Ap is the area of the header piping.

Transient Pressure Rise on Valve Closing This is the estimated magnitude of the positive pressure wave that will be superimposed on the line pressure when the relief valve slams shut. This positive pressure wave will move back through the relief system piping similar to the pressure wave in the supply side piping of a water hammer type system. The magnitude of this wave is estimated from: r*c*dv where r is the gas density, c is the speed of sound in the gas and dv is the change in the velocity of the gas.

Thermodynamic Entropy Limit /Subsonic Vent Exit Limit These values should always be greater than 1. If either of these computed limits fall below 1.0 then the thermodynamic assumptions made regarding the gas properties are incorrect and the computed thrust values should be disregarded.

Valve Orifice Gas Conditions /Vent Pipe Exit Gas Conditions/Subsonic Velocity Gas Conditions These are the thermodynamic properties of the gas at three critical points in the relief system. These three points are shown in the figure on the opposite page. The entire formulation for the thrust gas properties is based on an ideal gas equation of state. If the pressures and temperatures displayed above for the gas being vented are outside of the range where the ideal gas laws apply then some alternate source should be sought for the computation of the system’s thrust loads. In addition, all three of these points should be sufficiently clear of the gas saturation line. When the exit gas conditions become saturated, the magnitude of the thrust load can be reduced significantly. In this case the manufacturer should be consulted. In several instances at COADE, saturated exhaust thrust loads were 50 to 75% less than the CAESAR II computed values.

Relief Load Synthesis for Liquids CAESAR II assumes that the liquid vent system has one of the two following configurations:

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The input for the liquid relief load synthesis is shown as follows:

Relief Valve or Rupture Disk Enter “RV” if the relieving device is a relief valve and “RD” if the relieving device is a rupture disk. If the user has his own relief exit coefficient it can be entered here in place of the letters RV or RD. An entry of zero represents No appreciable head loss due to the relief opening configuration. The exit coefficient for a relief valve is 0.25 and for a rupture disk is 0.5.

Supply Overpressure Enter the stagnation, or zero velocity pressure in the fluid upstream of the relief valve.

ID Relief Orifice or Rupture Disk Opening Enter the manufacturers inside diameter of the contracted opening in the particular relieving device. (For special purpose calculations this ID may be equal to the ID of the Relief exit piping.)

ID Relief Exit Piping Enter the inside diameter of the piping connected to the downstream side of the relief valve.

ID Manifold Piping If the relief exit piping runs into a manifold then enter the inside diameter of the manifold. Leave this field blank or zero if there isn't a manifold.

ID Supply Header Enter the inside diameter of the supply header.

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Fluid Density Enter the specific gravity of the fluid being relieved.

Length of Relief Exit Piping Enter the equivalent length of the relief exit piping. Add twice the piping length for fittings and elbows, or the calculated fitting equivalent length.

Length of Manifold Piping Enter the equivalent length of the manifold piping, if any. If there isn't a manifold system then leave this field blank or zero. Add twice the piping length for fitting and elbows. If the manifold is not filled by the relieving fluid then leave the manifold length zero.

Fluid Bulk Modulus Enter the bulk modulus of the fluid. If omitted a valve of 250,000 psi will be used as the default. Some typical values for use are given as follows. These are the values for an isothermal compression as taken from “Marks Standard Handbook for Engineers,” p. 3-35, 8th edition.

Supply Header Pipe Wall Thickness Enter the wall thickness of the supply header. Note: When running the relief load synthesis for liquids, the error message: NUMERICAL ERROR OR NO FLOW CONDITION DETECTED, means a physically impossible configuration was described. Flashing of volatile relief liquids is not considered. If the relieving liquid flashes in the exhaust piping as its pressure drops to atmospheric then some other means should be used to compute the resulting gas properties and thrust Loads.

Output From the Liquid Relief Load Synthesizer Computed Mass Flow rate The computed exhaust mass flow rate in U.S. Gallons per minute. CAESAR II makes the necessary pressure drop calculations between the stagnation pressure upstream of the relief device and atmospheric conditions at the exit of the manifold.

Thrust at the End of the Exit Piping The computed thrust load at the last cross section in the exit piping. If there is no manifold then this is the external thrust load that acts on the piping system. If there is a manifold then this thrust is opposed by tension in the pipe wall at the junction of the exit piping and manifold. See the figures that follow for clarification.

Thrust at the End of the Manifold Piping The computed thrust load at the last cross section in the manifold piping. If there is no manifold system then this thrust will be equal to the thrust at the end of the exit piping. See the figures that follow for clarification.

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Transient Pressure Rise on Valve Opening This is the estimated magnitude of the negative pressure wave that will be superimposed on the line pressure when the relief valve fist opens. This negative pressure wave will move back through the relief system piping similar to the pressure wave in the downstream piping of a water hammer type system. The magnitude of this wave is estimated as (Po-Pa)*Ap, where Po is the stagnation pressure at the source, Pa is atmospheric pressure, and Ap is the area of the header piping.

Transient Pressure Rise on Valve Closing This is the estimated magnitude of the positive pressure wave that will be superimposed on the line pressure when the relief valve slams shut. This positive pressure wave will move back through the relief system piping similar to the pressure wave in the supply side piping of a water hammer type system. The magnitude of this wave is estimated from: r*c*dv where r is the gas density, c is the speed of sound in the gas and dv is the change in the velocity of the gas.

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Orifice Flow Conditions/Exit Pipe End Flow Conditions/Manifold Pipe End Flow Conditions These are the computed fluid properties at the three critical cross-sections in the relief piping. If pressures or velocities here do not seem reasonable then some characteristic of the relief model is probably in error.

Note: If the “L” dimensions are significant in any of the previous figures (several feet) then unbalanced thrust loads will act between the elbow-elbow pairs that is very similar to a water hammer load. Water hammer pulses travel at the speed of sound in the fluid, while the fluid/atmosphere interface “pulses” travel at the velocity of the flowing fluid. For this reason, these unbalanced loads can cause significant piping displacements in much shorter pipe runs. The magnitude of these loads is equivalent to the computed thrust and the duration may be found from the computed fluid velocity and distance between each elbow-elbow pair.

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CHAPTER 6

Technical Discussions In This Chapter Rigid Element Application ..........................................................2 Cold Spring .................................................................................4 Expansion Joints..........................................................................7 Hanger Sizing Algorithm.............................................................10 Class 1 Branch Flexibilities.........................................................14 Modeling Friction Effects ...........................................................17 Nonlinear Code Compliance .......................................................19 Sustained Stresses and Nonlinear Restraints ...............................20 Static Seismic Loads ...................................................................24 Wind Loads .................................................................................27 Hydrodynamic (Wave and Current) Loading ..............................30 Evaluating Vessel Stresses ..........................................................44 Inclusion of Missing Mass Correction.........................................49 Fatigue Analysis Using CAESAR II............................................54 Pipe Stress Analysis of FRP Piping.............................................70 Code Compliance Considerations ...............................................93 Local Coordinates .......................................................................127

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Rigid Element Application CAESAR II forms rigid elements by multiplying the wall thickness of the element by 10. The inside diameter, and the weight of the element, remain unchanged. The “rigid” element in CAESAR II is rigid relative to the pipe around it. If a 6-in. line ties into a 72-in. heat exchanger, then the rigid elements modeling the heat exchanger should have a diameter closer to 72 than 6. The user that is sensitive to the “rigidness” of the rigid element can increase or decrease the diameter or wall thickness of the rigid to simulate any order of magnitude stiffness.

Rigid Material Weight The weight of the rigid element is entered by the user. If no value is input then the weight of the rigid is taken to be zero. The entered weight is the weight of the rigid excluding insulation or fluid. If the weight of the rigid element is entered as zero or blank, then no additional weight due either to insulation or fluid will be added.

Rigid Fluid Weight CAESAR II automatically adds fluid loads for rigid elements if a non-zero fluid density is entered on the pipe spreadsheet. The fluid weight in a rigid element is assumed to be equal to the fluid weight in an equivalent straight pipe of similar length and inside diameter.

Rigid Insulation Weight CAESAR II also automatically adds insulation loads if the line containing the rigid element is insulated. The insulation weight for the rigid is assumed to be equal to 1.75 times the insulation for an equivalent length of straight pipe of equal outside diameter. The cumulative rigid element weight calculation is as follows: Weight = 0.0

Wu

=

Weight = Wu + Wf + 1.75Wi Wu

>

0.0

0.0

Where: Wu

=

User entered rigid weight

Wf

=

Calculated fluid weight for equivalent straight pipe

Wi

=

Calculated insulation weight for equivalent straight pipe

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3

The user’s entered weight for the rigid element is not reflected in the Thermal Expansion/Pipe Weight Report optionally printed during error checking. Stresses are not calculated on Rigid elements since they are often used to simulate components that have variable cross-sections along the length of the element, i.e. a valve, and is normally not of concern for this type of analysis anyway. Forces and Moments are not normally printed on nodes between two rigid elements, but can be by selecting the appropriate check box found in Kaux-Special Execution Parameters from the Piping Input Spreadsheet. Zero-weight rigids ("dummy" rigids) are often used to model components whose weight is not important to the analysis, but where thermal growth may be a consideration. Dummy rigids are often used to model restraints. Tie rods in an expansion joint, rod hangers, and trunnions are examples of restraints modeled as dummy rigids. Dummy rigids may also be used to provide connectivity between the center line of an element and its outside edge. The most common example of this is the addition of a dummy rigid that runs from the node at the center line of the vessel to the edge where a nozzle is to be connected. Sometimes equipment is modeled through a series of rigid elements. This is particularly true when multiple nozzles are attached and the equipment is restrained such that the interactions between the various nozzles must be taken into account due to the thermal growth of the attached piping system. The use of dummy rigids is explained in the CAESAR II Applications Guide in various sections as appropriate to a particular modeling technique.

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Cold Spring Cold spring is the process of offsetting (or pre-loading) the piping system with displacement loads (usually accomplished by cutting short or long the pipe runs between two anchors) for the purpose of reducing the absolute expansion load on the system. Cold spring is used to do the following: hasten the thermal shakedown of the system in fewer operating cycles reduce the magnitude of loads on equipment and restraints, since often, only a single application of a large load is sufficient to damage these elements

Several things should be considered when using cold spring: Cold reactions on equipment nozzles due to cold spring should not exceed nozzle allowables. The expansion stress range should not include the effect of the cold spring. The cold spring should be much greater than fabrication tolerances. Note: No credit can be taken for cold spring in the stress calculations, since the expansion stress provisions of the piping codes require the evaluation of the stress range, which is unaffected by cold spring (except perhaps in the presence of non-linear boundary conditions, as discussed below). The cold spring merely adjusts the stress mean, but not the range. Many engineers avoid cold spring due to the difficulty of maintaining accurate records throughout the operating life of the unit. Future analysts attempting to make field repairs or modifications may not necessarily know about (and therefore include in the analysis) the cold spring specification. Due to the difficulty of properly installing a cold sprung system, most piping codes recommend that only 2/3 of the specified cold spring be used for the equipment load calculations. The cold spring amount is calculated as: Ci = 1/2Li

dT

Chapter 6 Technical Discussions

Where: Ci = length of cold spring in direction i (where i is X, Y, or Z), (inches) Li = total length of pipe subject to expansion in direction i, (inches) = mean thermal expansion coefficient of material between ambient and operating temperature, (in/in/°F) dT = change in temperature, (°F)

5

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Note that the 1/2 in the equation for the cold spring amount is used such that the mean stress is zero. In some cases it is desirable to have the operating load on the equipment as close to zero as possible. In this latter case the 1/2 should be omitted. The maximum stress magnitude will not change from a system without cold spring, but will now exist in the cold case rather than the hot. To model a cold spring in CAESAR II specify the elements as being made of cut short or cut long materials. Cut short describes a cold sprung section of pipe fabricated short by the amount of the cold spring, requiring an initial tensile load to close the final joint. Cut long describes a cold sprung section of pipe fabricated long by the amount of cold spring, requiring an initial compressive load to close the final joint. The software models cut shorts and cut longs by applying end forces to the elements sufficient to reduce their length to zero (from the defined length) or increase their length to the defined length (from zero) respectively. (It should be remembered to make the lengths of these cold spring elements only 2/3 of their actual lengths to implement the code recommendations.) This is effectively what occurs during application of cold spring. The end forces applied to the elements are then included in the basic loading case F (for force), whereby they can be included in various load combinations. Special material numbers 18 and 19 are used to signal CAESAR II that the element currently in the spreadsheet actually represents a length of pipe that is to be cut short or long during fabrication. Material # 18 - Cut Short Material # 19 - Cut Long The user should be sure to reset the material property on the element following the cold spring element. The following load cases are recommended when analyzing a cold spring system:

RUN # 1

Load Case 1 (OPE)

W+T1+P1+CS includes all of the design cold spring

Load Case 2 (OPE)

W+P1+CS includes all of the design cold spring but not the temperature.

Load Case 3 (SUS)

W+P1 standard sustained case for Code Stress check

Load Case4 (EXP)

L1-L2 expansion case for code stress check.

Cold spring is allowed to reduce the magnitude of equipment loads because, often, only a single application of a large load is sufficient to cause damage to rotating machinery. Cold spring does not change the “range” of stresses that the piping system is subject to, and so, no allowance is given for stress reduction. (The maximum value of the stress is lowered, but the range is unchanged.) Both the sustained loads and the operating loads should be within the manufacturer’s allowables for the particular piece of equipment. If the designer isn't careful, the installation of the cold spring in the ambient state can overload a piece of rotating equipment as the unit starts up.

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Expansion Joints To define an expansion joint, activate the Expansion Joint check box (see "Expansion Joints" on page 19) on the pipe element spreadsheet. Expansion joint elements may have a zero or nonzero length. The expansion joint will have a zero length if the Delta fields in the spreadsheet are left blank or zero. The expansion joint will have a nonzero length if at least one of the element’s spreadsheet Delta fields is non-blank and non-zero. When an expansion joint has a finite length CAESAR II evenly distributes the expansion joint stiffnesses over the entire length of the element. This will usually result in a more accurate stiffness model in what is typically a very sensitive area of the piping system. Four stiffnesses define the expansion joint Axial Stiffness Transverse Stiffness Bending Stiffness Torsional Stiffness These stiffnesses are defined as shown in the following figure:

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The transverse and the bending stiffnesses are directly related when a finite length joint is defined. In this case the bending stiffness should be left blank and the transverse stiffness entered. CAESAR II will compute the proper bending stiffness from the relationship between the bending and transverse stiffnesses. Bending stiffnesses from manufacturers catalogs should generally only be entered for zero length expansion joints modeling hinges or gimbals. Before a manufacturers bending stiffness is used for a finite length bellows it should be multiplied by 4.0 (note that in this case the transverse stiffness would be left blank). Torsional stiffnesses are often not given by expansion joint manufacturers. In this case the user is recommended to insert a large torsional stiffness value and ensure that the resulting load on the bellows is not excessive. When the piping system is tight, and the diameter large, the magnitude of this “large” torsional stiffness can significantly effect the magnitude of the torsion carried by the bellows, i.e. stiffnesses of 100,000 in.lb./deg. and 1E12 in.lb./deg. can produce considerably different torsional load results. The tendency would be to go with the larger stiffness, i.e. being conservative, except that the torsional stiffness value is probably closer to the 100,000 in.lb./deg. In the instance where the “largeness” of the torsional stiffness value is important, the manufacturer should be pressed for his “best-guess” at the stiffness, or the following equation should be used to get an estimate, which the user can then conservatively increase to get reasonable torsional loads on the bellows and surrounding equipment. The equation for estimating bellows torsional stiffness is

( Re)3 (t )( E ) (1 + ) L Where =

3.14159

Re =

Expansion joint effective radius

t

=

Bellows thickness

E

=

Elastic Modulus

=

Poisson’s Ratio

=

Flexible bellows length

L

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9

When the expansion joint has a zero length, none of the expansion joint stiffnesses are related. The user must be sure that a value is entered into all four of the Stiffness fields. CAESAR II will calculate pressure thrust on the expansion joint if the bellows effective id is given in the expansion joint auxiliary screen. The mathematical model for pressure thrust applies a force equal to the pressure times the effective area of the bellows at either end of the expansion joint. The force will tend to open the bellows if the pressure is positive, and close the bellows if the pressure is negative. Users should note that this model does not exactly distribute the pressure loads correctly in the vicinity of the expansion joint. In most cases the misapplied load does not effect the solution. There are two components of the pressure thrust to be applied in practice, rather than the one component applied in the model. The first component is equal to the pressure times the inside area of the pipe and acts at the first change in direction of the pipe on either side of the expansion joint. This load will tend to put the pipe wall between the change in direction and the expansion joint in tension. The second component is equal to the pressure times the difference between the bellows effective area and inside pipe area. This load acts at the end of the expansion joint and tends to open the bellows up, putting the pipe between the expansion joint and the change in direction in compression. In the mathematical model the full component of the pressure thrust force is placed on the ends of the bellows instead of having a portion shifted out on either side of the expansion joint. A large number of expansion joint examples can be found in Chapter 5 of the Applications Guide.

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Hanger Sizing Algorithm The basic function of the hanger design algorithm is to calculate the hot load and travel for user-specified hanger locations. Once the hot load and travel are known, spring tables are entered and the theoretical cold load is calculated for each spring in the table.

Spring Design Requirements The smallest single spring that satisfies all design requirements is selected as the designed spring. The spring design requirements are 1

Both hot and the cold loads must be within the spring allowed working range.

2

If the user specified an allowed load variation then the absolute value of the product of the travel and the spring rate divided by the hot load must be less than the specified variation.

3

If the user specified some minimum available clearance then the spring selected must fit in this space.

If a single spring cannot be found that satisfies the design requirements, CAESAR II will try to find two identical springs that do satisfy the requirements. If satisfactory springs cannot be found, CAESAR II recommends a constant effort support for the location. There are several variations of this approach that arise due to the different design options available in CAESAR II, but for the most part the general algorithm remains unchanged.

Restrained Weight Case Hanger hot loads are calculated in the “restrained weight” case. In any job, if a hanger is to be designed, the first analysis case that must be run is the “restrained weight” case. This case usually includes weight, pressure and concentrated loads. For the “restrained weight” run, rigid “Y” restraints are placed at each hanger location, and any anchors to be freed are properly released. Loads on the “Y” restraints at hangers, calculated from the “restrained weight” case, are the hanger hot design loads.

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11

Operating Case Immediately after the “restrained weight” case, an operating analysis is performed. The “Y” restraints are removed from the hanger locations and the hot loads just calculated are inserted. Any anchors that were freed for the “restrained weight” analysis are fixed. The operating case vertical displacement at each hanger location defines that hanger’s “travel.” If there were single directional restraints or gaps in the system that changed status in the operating case then the possibility exists that loads on hangers will be redistributed. When a nonlinear status change is detected CAESAR II reruns the “restrained weight” case with the restraints left as they were at the end of the operating case. New restraint loads are calculated and another operating case is run to get the updated “travel.” The operating case must always be the second load case in the set of defined analysis cases. The user has the ability to define the “restrained weight” or operating load cases for hanger design any way he sees fit. For simplicity, CAESAR II recommends the load cases it thinks should be run whenever it detects the first attempt to analyze a particular system. The user can accept or reject CAESAR II’s recommendations. The user that sets up his own hanger design load cases should be sure he understands exactly what is done in the “restrained weight” and operating passes of the hanger design algorithm.

Installed Load Case If the user requested the calculation of the actual hanger installed loads, the third analysis level combination case must define the weight configuration that will exist in the field when the spring is installed. Typically this case includes weight without fluid contents and concentrated loads. The theoretical cold, or installed, load is the load on the spring when the pipe has exactly zero displacement. The actual installed load may differ from the theoretical installed load by (K)(d), where (K) is the spring stiffness and (d) is the displacement of the pipe in the installed condition. In essence, the actual installed load is calculated by taking the piping system and “freezing” all displacements at zero. With the pipe in this condition, the hangers are installed and the theoretical cold load is applied. The pipe is then “defrosted” and allowed to adjust its weight position due to the hanger, restraint, and anchor stiffnesses and the installed hanger loads. Once the system settles out, the total load on each of the hangers is read and recorded as the “actual” hanger installed load.

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Setting Up the Spring Load Cases The load cases that must exist for hanger design, as described above, are Restrained Weight Operating Installed Weight ...if the user requested actual hanger installed loads. After the hanger algorithm has run the load cases it needs to size the hangers. The newly selected springs are inserted into the piping system and included in the analysis of all remaining load cases. The spring rate becomes part of the global stiffness matrix, and is therefore added into all subsequent load cases. Hanger installed loads are concentrated forces and are only included in subsequent load cases that contain the first concentrated force set, (i.e., +H). The user may specify any number of his own load cases after the required spring load cases are set up. Spring hanger design does not affect CAESAR II’s ability to check code compliance. In fact, in CAESAR II’s recommended load cases, the normal code compliance cases always follow the set of load cases required for hanger design. Multiple operating case spring hanger design implies that hanger loads and “travels” from more than one operating case are included in the spring hanger selection algorithm. Each spring in a multiple operating case hanger design has a multiple load case design option. This design option tells CAESAR II how the multiple loads and travels for a single hanger are to be combined to get a single design load and travel. The set-up of the analysis cases is slightly different for multiple operating case hanger design, and as might be expected, the difference is that now there is more than one operating case. The actual number of operating cases is specified by the user on the Hanger Design Control dialog and can be up to 9. Load cases that must be set up for a multiple load case hanger design that considers two hanger design operating cases are: Restrained Weight (this doesn't change) Operating case #1

Operating case #9 Installed Weight ...if the user requested that actual installed loads are to be calculated.

Constant Effort Support The specification of the support load for a constant effort hanger completely defines the hanger location. If the user enters this value it will be included in all hanger design runs and all analysis cases following the hanger cases that include concentrated loads in their formulation. This value is the load on each support at this location.

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13

Including the Spring Hanger Stiffness in the Design Algorithm The operating cases for hanger travel are normally analyzed with no stiffness included at the hanger locations (hence these cases are traditionally referred to as "free thermal" cases). However, when the piping system is very flexible, or the selected springs are very stiff, the actual resulting spring loads in the hot condition can vary significantly from the theoretically calculated results. In that case, CAESAR II offers the option to include (via an iterative process) the stiffness of the selected springs in the operating cases for hanger travel. This can be activated by setting the Hanger Stiffness Load Case option to "As Designed" for that operating case. (Activating the Configure/Setup option "Include Travel cases to default to "As Designed".) The user is warned that selection of this option may lead to convergence problems. If this option is used, it is very important that the hanger load in the cold case (In the physical system) be adjusted to match the reported hanger Cold Load. Spring Hanger Hot Loads for as designed springs are always included in all Operating Hanger Travel cases. Cold loads can be included in subsequent load cases through the use of the H load component. (Note that applying thermal and displacement effects to the system should make the Cold Load move to the Hot Load in the operating case.)

Other Notes on Hanger Sizing Users should note that whenever a hanger location is found to “hold the pipe down,” a beep and a warning message is flashed to the user. These locations in output are flagged as zero load constant effort supports. These supports are usually found to be at poor hanger design locations. Hanger design load cases, unless specifically designed with a "KEEP" status by the user, show up in the output report as being “NOT ACTIVE.” Results from these analysis are reflected in the spring hanger table only.

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CAESAR II Technical Reference Manual

Class 1 Branch Flexibilities This analytical option was added to CAESAR II for the following reasons: Automatic local flexibilities at intersections help the user bound the true solution. Because the computer time to do an analysis is getting less expensive, more frequently an analyst is running several solutions of the same model using slightly different input techniques to determine the effect of the modeling difference on the results. (This gives the analyst a degree of confidence in the numbers he is getting.) For example, structural steel supporting structures may be modeled to see the effect of their stiffnesses, nozzle flexibilities may be added at vessel connections to see how these features redistribute load throughout the model, friction is added to watch its effect on displacements and equipment loads, and with CAESAR II users may include Class 1 intersection flexibilities. The characteristic that makes this option convenient to use is that the use can turn the Class 1 flexibilities “on” and “off” via a single parameter in the setup file. There is no other modification to the input required. In WRC 329, there are a number of suggestions made to improve the stress calculations at intersections. These suggestions are fairly substantial, and are given in order of importance. The most important item, as felt by Rodabaugh in improving the stress calculations at intersections is given, in part, as follows: “In piping system analyses, it may be assumed that the flexibility is represented by a rigid joint at the branch-to-run centerlines juncture. However, the Code user should be aware that this assumption can be inaccurate and should consider the use of a more appropriate flexibility representation.” User of the Class 1 branch flexibility feature may be summarized as follows:The user adds the option: CLASS_1_BRANCH_FLEX to the setup file. This option is a flag, and merely has to appear in the setup file to activate the option. Where reduced branch geometry requirements are satisfied, CAESAR II constructs a rigid offset from the centerline of the header pipe to its surface, and then adds the local flexibility of the header pipe, between the end of the offset, at the header, and the start of the branch. Stresses computed for the branch, are for the point at its connection with the header. Where reduced branch geometry requirements are not satisfied, CAESAR II constructs a rigid offset from the centerline of the header pipe to its surface. The branch piping starts at the end of this rigid offset. There is NO local flexibility due to the header added. (It is deemed to be insignificant.) Stresses computed for the branch, are for the point at its connection with the header. The reduced branch geometry requirements checked by CAESAR II are d/D

0.5

and

Where: d = Diameter of branch D = Diameter of header T = Wall thickness of header

D/T

100.0

Chapter 6 Technical Discussions

15

When the Class 1 branch flexibilities are used, intersection models in the analysis will become stiffer when the reduced geometry requirements do not apply, and will become more flexible when the reduced geometry requirements do apply. Stiffer intersections typically carry more load, and thus have higher stresses (lowering the stress in other parts of the system that have been “unloaded”). More flexible intersections typically carry less load, and thus have lower stresses, (causing higher stresses in other parts of the system that have “picked up” the extra load). The branch flexibility rules used in CAESAR II are taken from ASME III, Subsection NB, (Class 1), 1992 Edition, Issued December 31, 1992, from Code Sections NB-3686.4 and NB-3686.5. When the reduced branch rules apply, the following equations are used for the local stiffnesses: TRANSLATIONAL: AXIAL

=

RIGID

CIRCUMFERENTIAL

=

RIGID

LONGITUDINAL

=

RIGID

ROTATIONAL: AXIAL

=

RIGID

CIRCUMFERENTIAL

=

(kx)d/EI

LONGITUDINAL

=

Where: RIGID

=

1.0E12 lb./in. or 1.0E12 in.lb./deg.

d

=

Branch diameter

E

=

Young’s Modulus

I

=

Cross Section Moment of Inertia

D

=

Header diameter

T

=

Header thickness

Tb

=

Branch fitting thickness

kx

=

0.1(D/T)1.5[(T/t)(d/D)]0.5(Tb/T)

kz

=

0.2(D/T)[(T/t)(d/D)]0.5(Tb/T)

(kz)d/EI

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CAESAR II Technical Reference Manual

Users are referred to WRC 329 Section 4.9 “Flexibility Factors.” A brief quote from this section follows: “The significance of “k” depends upon the specifics of the piping system. Qualitatively, if “k” is small compared to the length of the piping system, including the effect of elbows and their k-factors, then the inclusion of “k” for branch connections will have only minor effects on the calculated moments. Conversely, if “k” is large compared to the piping system length, then the inclusion of “k” for branch connections will have major effects. The largest effect will be to greatly reduce the magnitude of the calculated moments acting on the branch connection. To illustrate the potential significance of “k’s” for branch connections, we use the equation [above] to calculate “k” for a branch connection with D=30 in., d=12.75 in. T=t=0.375 in.: k = 0.1(80)1.5(0.425)0.5 * (1.0) = 46.6 This compares to the more typical rigid-joint interpretation that k=1, rather than k=46.6 !” Further discussion in section 4.9 illustrates additional problems that can arise by overestimating the stiffness at branch connections. Problems arise by believing “mistakenly” that the stress at the intersection is too high. Further reference should be made to this section in WRC 329. The branch automatic flexibility generation can be used where the user has only defined the branch element in the model, i.e. has left the header piping out of the analysis. In this case there will be no “offset” equal to one-half of the header diameter applied to the branch end. A “partial intersection” is one where either the header pipe is not modelled, is modelled with a single element, or is part of a geometric intersection where the header pipes are not colinear. In the case where there is no header pipe going to the intersection there will be no modification to the model for the class 1 branch flexibilities. When at least a single header pipe is recognized, the local flexibility directions are defined by the branch alone and in accordance with the CAESAR II defaults for circumferential and longitudinal directions for the branch and header. Users are recommended to build full intersection models at all times (not only when employing the class 1 branch flexibility.) In most cases building full intersection models will eliminate problems caused by the assumptions necessary when a partial intersection is described. In the equations in NB-3686.5 for tn, the thickness of the branch pipe is used in all cases. When branches are skewed with respect to the header pipe, and where the two header pipes are colinear, the local Class 1 flexibilities are still taken to be the longitudinal and circumferential directions that are tangent to the header surface at its intersection with the branch. Class 1 branch flexibilities can be formed at both ends of a single pipe element. Note: The offsets necessary to form the class 1 intersections are automatically generated by CAESAR II. There is no extra input required by the user to have CAESAR II build these intersections. (If there are already user-defined offsets at an intersection end, the computed offset to get from the header centerline to its surface along the centerline of the branch will be added to the already entered user offset.) Automatic offsets will be generated providing that the distance from the header centerline to the header surface along the branch centerline is less than or equal to 98% of the total pipe straight length. When a bend curved element is part of an intersection model, the offset and flexibility calculations will not be performed.

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17

Modeling Friction Effects There are two approaches to solving the friction problem; insert a force at the node which must be over come for motion to occur, or insert a stiffness which applies an increasing force up to the value of Mu * Normal force. CAESAR II uses the restraint stiffness method. (An excellent paper on this subject is “Inclusion of a Support Friction Into a Computerized Solution of a Self-Compensating Pipeline” by J. Sobieszczanski, published in the Transactions of the ASME, Journal of Engineering for Industry, August 1972. A summary of the major points of this paper can be found below.) Ideally, if there is motion at the node in question, the friction force is equal to (Mu * Normal force). However, since we have a non-rigid stiffness at that location to resist the initial motion, the node can experience displacements. The force at the node will be the product of the displacement and the stiffness. If this resultant force is less than the maximum friction force (Mu * Normal force), the node is assumed to be “not sliding,” even though we see displacements in the output report. The maximum value of the force at the node is the friction force, Mu * Normal force. Once this value is reached, the reaction at the node stops increasing. This constant force value is then applied to the global load vector during the next iteration to determine the nodal displacements. Basically here is what happens in a “friction” problem. 1

The default friction stiffness is 1,000,000 lb./in. This value should be decreased to improve convergence.

2

Until the horizontal force at the node equals Mu * Normal force, the restraint load is the displacement times the friction stiffness.

3

Once the maximum value of the friction force is reached, the friction force will stop increasing, since a constant effort force is inserted.

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By increasing the friction stiffness in the setup file, the displacements at the node will decrease to some degree. This may cause a re-distribution of the loads throughout the system. However, this could have adverse affects on the solution convergence. If problems arise during the solution of a job with friction at supports, reducing the friction stiffness will usually improve convergence. Several runs should be made with varying values of the friction stiffness to insure the system behavior is consistent. Summary of J. Sobieszczanski’s ASME Paper For dry friction, the friction force magnitude is a step function of displacement. This discontinuity determines the problem as intrinsically nonlinear and eliminates the possibility of using the superposition principle. The friction loading on the pipe can be represented by an ordinary differential equation of the fourth order with a variable coefficient that is a nonlinear function of both dependent and independent variables. No solution in closed form is known for an equation of this type. Solution has to be sought by means of numerical integration to be carried out specifically for a particular pipeline configuration. Dry friction can be idealized by a fictitious elastic foundation, discretized to a set of elastic (spring) supports. A well-known property of an elastic system with dry friction constraints is that it may attain several static equilibrium positions within limits determined by the friction forces. THE WHOLE PROBLEM THEN HAS CLEARLY NOT A DETERMINISTIC, BUT A STOCHASTIC CHARACTER.

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19

Nonlinear Code Compliance Nonlinear piping code compliance can be directly satisfied by 1

Performing an operating and sustained analysis of the system including in each case the effect of nonlinear restraints.

2

Subtracting the sustained case displacements from the operating case displacements to find the “displacement range.”

3

Calculating the expansion stresses from the displacement range solved for in #2 above.

Approximate approaches usually involve some combination of the above. The approximate combination used depends typically on the inherent limitations of the base program. In several commonly used programs, the approach taken is 1

Formulate and solve for operating case displacements including an iteration to deal with the effect of nonlinear restraints in the system.

2

Run the thermal-only analysis of the system to calculate expansion stresses with restraints in the same condition as they were at the end of #1.

3

Run the weight+pressure only analysis of the system to calculate sustained stresses, again with restraints in the same condition as they were at the end of #1.

This alternate approach is identical to the first method only when the sustained analysis final stiffness matrix is the same as the operating analysis final stiffness matrix. The resulting error in the displacement range can be found from {[Fo] - [Fs]}fs. Where: [Fo] is the operating analysis final flexibility matrix. (i.e. the inverse of the stiffness matrix.) [Fs] is the sustained analysis final flexibility matrix. fs is the sustained analysis load vector. CAESAR II uses the exact method described above for calculating the expansion stress range. In addition CAESAR II scans the user’s input and recommends loading cases and combinations for performing the operating, sustained and expansion stress calculations. This recommendation can prove very useful when performing spring hanger analysis of a multiple operating case system.

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CAESAR II Technical Reference Manual

Sustained Stresses and Nonlinear Restraints The proper computation of sustained stresses has been an issue since the late 1970s, when computerized pipe stress analysis programs first attempted to address the problem of non-linear restraints. The existing piping codes offered little guidance on the subject, since their criteria were developed during the era when all analyses were considered to behave in a strictly linear fashion. The problem arises because the codes require that a piping system be analyzed separately for sustained loadings — the engineer must determine which stresses are caused by which loadings. Sustained loads are force loadings which are assumed not to change, while expansion loadings are displacement loadings which vary with the system operating conditions. Determination of the sustained loads is the simple part — most everybody agrees that those forces consist of weight, pressure, and spring preloads — these forces remain relatively constant as the piping system goes through its thermal growth. However, confusion occurs when the status of nonlinear restraints change (pipes lift off of supports, gaps close, etc.) as the pipe goes from its hot to cold state — in this case, which boundary conditions should be used when evaluating the applied forces? Or in other words, what portion of the stress in the operating case is caused by weight loads, and what portion is caused by expansion effects? (Note that there is no corresponding confusion on the question of calculating expansion stresses, since the codes are explicit in their instructions that the expansion stress range is the difference between the operating and cold stress distributions, both of which are known.) The obvious answer to this question, to the developers of some pipe stress programs, was that the sustained stress calculation should be done using the operating, or hot boundary condition. This compounded the problem, in that the laws of superposition no longer held — in other words, the results of sustained (W+P) and thermal (T) cases, when added together, did not equal the results of the operating (W+P+T) case! One pioneering program, DYNAFLEX, attempted to resolve this by introducing the concept of the “thermal component of weight” — an oxymoron, in our opinion. Other programs, notably those which came from the mainframe/linear analysis world, had to approximate the behavior of these non-linear restraints. Their approach to the problem is to run an operating case, obtain the restraint status, and modify the model according to these results. All subsequent load cases analyzed use this restraint configuration. The fact that the laws of static superposition didn't hold was hopefully not noticed by the user. CAESAR II, on the other hand, represents new technology, developed expressly for operation on the PC, and therefore incorporates directly the effects of non-linear restraints. This is done by considering each load case independently — the restraint configuration is determined for each load case by the program as it runs, based upon the actual loads which are considered to be present. Some users have asserted that there are actually two sustained load cases. In fact, there has been a B31.3 code interpretation that indicates that the sustained stress may also be checked with the operating restraint configuration. Calculating the sustained stresses using the operating restraint status raises several other issues; what modulus of elasticity should be used, and which sustained stresses should be used for occasional cases.

Chapter 6 Technical Discussions

21

It is COADE’s assertion that there is only one sustained case (otherwise it is not “sustained”) — there can be, however, multiple sustained stress distributions. The two most apparent are those associated with the cold (installed) and hot (operating) configurations, however, there are also numerous in-between, as the piping system load steps from cold to hot. Whether the “true” sustained load case occurs during the installed or operating case is a matter of the frame of reference. If an engineer first sees a system in its cold condition, and watches it expand to its operating condition, it appears that the first case (since weight and pressure — primary loads — are present) is the sustained case, and the changes he viewed are thermal effects (due to heat up) — secondary loads due to displacements. If a second engineer first sees the same system in the operating case and watches it cool down to the cold case, he may believe that the first case he saw (the operating case) is the sustained case, and changes experienced from hot to cold are the thermal expansion effects (the thermal stress ranges are the same in both cases). Consider the further implications of cryogenic systems — where changes from installed to operating are the same as those experienced by hot systems when going from operating to installed. Once elastic shakedown has occurred, the question becomes clouded even further, due to the presence of thermally induced pre-stresses in the pipe during both the cold and hot conditions. We feel either the operating or installed case (or some other one inbetween) could justifiably be selected for analysis as the sustained case, as long as the program is consistent. We have selected the installed case (less the effect of cold spring) as our reference sustained case, since thermal effects can be completely omitted from the solution (as intended by the code), and this best represents the support configuration when the sustained loads are initially applied. If the pipe lifts off of a support when going from installed to operating, we view this as a thermal effect — consistent with the piping codes’ view of thermal effects as the variation of stress distribution as the piping system goes from cold to hot (this view is explicitly corroborated by one code — the French petrochemical code, which states that weight stress distributions due to thermal growth of the pipe should be considered as expansion stresses). For example, we feel that a change in a rigid support load from 2,000 lbs to zero should be treated no differently than would be a variable spring load changing from 6,000 lbs to 4,000 lbs (or another rigid support load going 2,000 lbs to 1 lb). In the former case, if the pipe became “overstressed”, it would yield, and sag back to the support, relieving the stress. This process is identical to the way that all other expansion stresses are relieved in a piping system. We are confident that our interpretation is correct. However, we understand that our users may not always agree with us — that is why CAESAR II provides the greatest ability to custom tailor the analysis to one’s individual specifications. If desired, a “hot sustained” case can be analyzed by adding two load cases to those normally recommended by CAESAR II. This would be done by assuming that the pipe expands first, and then the sustained loads are applied (this is of course an idealized concept, but the stresses can only be segregated by segregating the applied loads, so the sustained loads can only be applied either before, or after, the expansion loads). Following are the default load cases, as well as those required for a “hot sustained.” Default

New

W+P1+T1(OPE)

W+P1+T1(OPE)

W+P1(SUS)

W+P1(SUS)

L1-L2(EXP)

T1 (EXP) L1-L2(EXP) L1-L3(SUS)

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CAESAR II Technical Reference Manual

In the new load case list, the second case still represents the cold sustained, while the fourth case represents the expansion case (note that L1-L2, or W+P1+T1-W-P1, equals T1, with non-linear effects taken into account). The third case represents the thermal growth of the “weightless,” non-pressurized pipe, against the non-linear restraints. The fifth case (L1-L3, or W+P1+T1-T1, equals W+P1) represents the application of weight and pressure to that expanded case, or the “hot sustained” case. Note that when the piping system is analyzed as above, the actual effects of the non-linear restraints are considered (they are not arbitrarily removed from the model), and the laws of superposition still hold. An alternative school of thought believes that a "hot sustained" is only valid if (1) the sustained, primary loads are applied, (2) all springs are showing their Hot Load settings, and (3) any supports that lift off (or otherwise become non-active) have been removed from the model. An analysis such as this is achievable by setting the "Keep/Discard" status of the Restrained Weight case (the first hanger design load case) to "Keep", thus permitting the results of that case to be viewable as for any other load case. The Restrained Weight case automatically removes restraints that become non-active during the designated operating case, and apply the Hot Load at each of the hanger locations.

Chapter 6 Technical Discussions

23

Notes on Occasional Load Cases Several piping codes require that the stresses from occasional loads (such as wind or earthquake) be added to the sustained stresses (due to weight, pressure, and other constant loads) before comparing them to their allowables. This combination is easily created in CAESAR II: CASE #

1

W+P+F1

(SUS)

2

WIND

3

U1

4

L1+L2

(OCC)

:Code stresses for wind *

5

L1+L3

(OCC)

:Code stresses for earthquake*

(OCC)

:Sustained stresses :Wind load set

(OCC)

:Uniform (g) load set for earthquake

* Scalar Summation Method required If nonlinear effects are modeled in the system these combinations may not be so straight forward. Friction, one-direction restraints and double-acting restraints with gaps are the nonlinear items which present this complication. Wind loading on a long vertical run of pipe with a guide will serve as an example. Assume there is a one inch gap between the pipe and guide. Under normal operation, the pipe moves 3/4 inch towards the stop leaving a gap of 1-3/4 inch on either side of the pipe and a 1/4 inch gap on the other side. If wind loads are analyzed alone, the pipe is allowed to move 1 inch from its center point in the guide to the guide stop. Since occasional loads are usually analyzed with the system in operation, the pipe may be limited to a 1/4 inch motion as the gap is closed in one direction, and 1-3/4 inch if the gap is closed in the opposite direction. With nonlinear effects modeled in the system, the occasional deflections (and stresses) are influenced by the operating position of the piping. The following list of CAESAR II load cases take this point into consideration. Note that the load cases shown below are only for wind acting in one direction, i.e., +X. Depending on the system, the most critical loads could occur in any direction, i.e., +/-X, +/-Z or skewed in an XZ direction. The intention of the following load case construction is to find the occasional load’s effect on the piping system in the operating condition. The stress due to the moment change from the operating to the operating plus wind case is added to the stress from the sustained case. The isolated wind effect on the piping system in the operating condition in is computed in Case 5. Case 6 adds the stresses from Case 5 to the sustained stresses from Case 2. CASE #

1

W+T+P

(OPE)

2

W+P

3

W+T+P+WIND

4

L1-L2

(EXP)

:Expansion stresses (Algebraic summation)

5

L3-L1

(OCC)

:Wind’s net deflection (Algebraic summation)

6

L2+L5

(OCC)

:Code stresses for wind (Scalar summation)

(SUS) (OPE)

:Operation analysis :Sustained stresses :Operating analysis with wind

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CAESAR II Technical Reference Manual

Static Seismic Loads Static earthquake loads are applied in a manner very similar to static wind loads. The static loading magnitude is considered to be in direct proportion to the element’s weight. Earthquake load magnitudes are given in terms of the gravitational acceleration constant, i.e. g’s. If an earthquake is modeled as having a 0.5-g load in the X direction, then half of the systems weight is turned into a uniform load and applied in the X direction. Earthquake static load cases are set up exactly as they are for wind occasional loads, i.e. the same load case, nonlinearity, and directional sensitivity logic. In some cases the client specifies the magnitude of the earthquake loading in g’s and the direction(s). In others, the analysis is left to the sole discretion of the analyst. It is not unusual to see only X or X-Y components of an earthquake. It is not uncommon to see Y only components, or X, Y, and Z simultaneous components. Dynamic earthquakes are discussed later in this chapter, in the dynamic analysis and output chapters, and in the screen reference chapter. The ASCE #7 method for determining earthquake coefficients is described below. Once calculated, the gfactors should be entered as uniform loads on the piping spreadsheet. Note: The Uniform Load in G's (on page 112) check box must also be enabled in the spreadsheet special execution parameters. The total lateral force at the base of a structure is to be computed from: V = ZIKCSW

Where: V - total lateral force or shear at the base Z—numerical coefficient from table 22 K—numerical coefficient from table 23 C—numerical coefficient from Sect. 9.4 S—soil factor from table 25 W—total dead load The g-factor can be found by dividing Eq. 6 through by W. g’s = V/W = ZIKCS

Chapter 6 Technical Discussions

25

The product CS does not need to exceed the value 0.14. Use this value as a conservative maximum. The following table provides the seismic zone coefficient (Z) . Seismic Zone Coefficient, Z 4

1

3

3/4

2

3/8

1

3/16

0

1/8

From the following table, the importance factor can be found: (However use a value for I = 1.0. The categories in this table are identical for those used in the wind load calculation.) The following table shows K varying from 0.67 to 2.0. Use K=2.0 for “Structures other than buildings.” So the equation for the “g” load: g = ZIKCS reduces to: g = Z (1.0) (2.0) (0.14) and for the various value of Z:

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CAESAR II Technical Reference Manual

Seismic Zone

Product

"g" Load

4

(1)(1)(2)(0.14)

0.28

3

(3/4)(1)(2)(0.14)

0.21

2

(3/8)(1)(2)(0.14)

0.105

1

(3/16)(1)(2)(0.14)

0.0525

0

(1/8)(1)(2)(0.14)

0.035

Seismic Zones from A58.1 - 1982 fig. 13, p.50

ASCE #7 - 1990 is the 1990 revision to ANSI A58.1 1982. There are no revisions to this code which affect CAESAR II. ASCE #7 - 1993 has completely changed the approach for "static" seismic analysis. These changes are not addressed by this discussion.

Chapter 6 Technical Discussions

27

Wind Loads Wind loads are generated by multiplying the pipe exposed area, including insulation, and considering angle to the wind, by the equivalent wind pressure and the pipe shape factor. There are typically three different ways to get at the equivalent wind pressure: ASCE #7 (1995) Pressure vs. elevation table entry Velocity vs. elevation table entry The total wind force on the element is calculated from F = PeqSA Where: F = the total wind force on the element Peq = the equivalent wind pressure (dynamic pressure) S = the pipe element wind shape factor A = the pipe element exposed area as shown in the figure as follows: Peq is calculated for each end of the element and the average taken. The average applies uniformly over the whole length of the element. Note, the wind force is applied in the three global directions as a function of the element direction cosines.

If the user enters a velocity vs. elevation table then the velocity is converted to a dynamic pressure using the following equation: P = 1/2 V2 where V is the wind velocity and

is the air density.

The WIND SHAPE FACTOR is entered on the pipe spreadsheet and, for cylindrical elements, the value from Table 12 is between 0.5 and 0.7. A value of 0.65 is typical. The wind shape factor as entered is “distributive.” This means that the shape factor applies for all following elements until zeroed or changed. Important The user does not have to enter the shape factor on each pipe spreadsheet. Zero (or turn "Off") the wind shape factor if the piping system runs inside of building or similarly protective structure. Wind load data is entered on the Wind Loads (on page 59) tab of the Static Load Case Builder. Up to four different wind loads can be entered per analysis. These typically might be set up to model wind loads in the +X, -Y, and -Z directions. The ASCE #7 ( 1995) Method for computing equivalent pressure requires several computerized table look ups and interpolation. The user enters the following parameters: 1

Basic wind speed (mph) - The minimum allowed basic wind speed is 85 mph. This does not include averages for abnormally high wind loading events such as hurricanes or tornadoes.

ASCE #7 refers to fig. 6-1 for basic wind speeds in the continental United States. The following description is a crude representation of Figure 1:

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CAESAR II Technical Reference Manual

California

85 mph (124.6 ft/sec)

Other West Coast Areas

85 mph (124.6 ft/sec)

Great Plains

90 mph (132.0 ft/sec)

Non-Coastal Eastern United States

90 mph (132.0 ft/sec)

Gulf Coast

130 mph (190.6 ft/sec)

Florida

Carolinas 130 mph (190.6 ft/sec)

Miami

145 mph (212.6 ft/sec)

New England Coastal Areas

120 mph (176.0 ft/sec)

2

Wind Exposure Options Large oily center Urban, suburban, and wooded areas Open terrain Flat coastal areas

3

Structural Classification Options Everything except the following options (used most often) Primary occupancy more than 100 people Essential facilities, i.e. hospitals Failure represents low hazard

4

Topographic Factor Parameters (sec. 6.5.5) Height of hill or escarpment Crest distance Height above ground level Distance from crest to site Hill type

The following procedure from the appendix is used to calculate the effective wind pressure: 1

Get the Importance Factor from Table 6-2 (p.17)

2

Get (Alpha), Zg, from Table C 6-2.

3

Calculate Kz from Eq. C2 (p.152)

4

Calculate Kzt from Eq. 6-2 (p.34)

5

Calculate qz from Eq. 6-1, (p.17)

6

Calculate Gz from sec 6.6

Chapter 6 Technical Discussions

7

29

Calculate the effective wind pressure from PRESSURE = Gz * qz * Shape Factor

Note: Winds of 20 to 40 mph can cause vortex shedding and excitation in the 30 Hz and higher range that can cause fatigue failure in smaller line sizes particularly susceptible to fatigue type failures. To analyze vortex shedding, use harmonic analysis methods.

Elevation The accurate elevation of each individual piping element may, or may not be important depending on the total height, diameter and rigidity of the piping system and attachments. By default, CAESAR II starts the first node on the first element at an elevation of 0.0. If this is not close enough to the true elevation then the user should set the true coordinates of the piping system through the command EDIT - GLOBAL. This presents a dialog requesting coordinates for the first node of any disconnected section. The coordinates for up to 100 node points can be specified and saved as part of the input data from the model.

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Hydrodynamic (Wave and Current) Loading Ocean waves are generated by wind and propagate out of the generating area. The generation of ocean waves is dependent on the wind speed, the duration of the wind, the water depth, and the distance over which the wind blows is referred to as the fetch length. There a variety of two dimensional wave theories proposed by various researchers, but the three most widely used are the Airy (linear) wave theory, Stokes 5 th Order wave theory, and Dean's Stream Function wave theory. The later two theories are non-linear wave theories and provide a better description of the near surface effects of the wave. (The term two dimensional refers to the uni-directional wave. One dimension is the direction the wave travels, and the other dimension is vertical through the water column. Two dimensional waves are not found in the marine environment, but are somewhat easy to define and determine properties for, in a deterministic sense. In actuality, waves undergo spreading, in the third dimension. This can be easily understood by visualizing a stone dropped in a pond. As the wave spread, the diameter of the circle increases. In addition to wave spreading, a real sea state includes waves of various periods, heights, and lengths. In order to address these actual conditions, a deterministic approach can not be used. Instead, a sea spectrum is utilized, which may also include a spreading function. As there are various wave theories, there are various sea spectra definitions. The definition and implementation of sea spectra are usually employed in dynamic analysis. Sea Spectra and dynamic analysis will not be discussed in this article.) The linear or Airy wave theory assumes the free surface is symmetric about the mean water level. Furthermore, the water particle motion is a closed circular orbit, the diameter of which decays with depth. (The term circular should be taken loosely here, the orbit varies from circular to elliptical based on whether the wave is in shallow or deep water.) Additionally, for shallow water waves, the wave height to depth ratio (H/D) is limited to 0.78 to avoid breaking. (None of the wave theories address breaking waves!) The figure below shows a typical wave and associated hydrodynamic parameters.

SWL - The still water level. L - The wave length, the horizontal distance between successive crests or troughs. H- The wave height, the vertical distance between the crest and trough. D - The water depth, the vertical distance form the bottom to the still water level. # - The surface elevation measured from the still water level.

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Ocean Wave Particulars The Airy wave theory provides a good first approximation to the water particle behavior. The nonlinear theories provide a better description of particle motion, over a wider range depths and wave heights. The Stokes 5th wave theory is based on a power series. This wave theory does not apply the symmetric free surface restriction. Additionally, the particle paths are no longer closed orbits, which means there is a gradual drift of the fluid particles, i.e. a mass transport. Stokes 5th order wave theory however, does not adequately address steeper waves over a complete range of depths. Dean’s Stream Function wave theory attempts to address this deficiency. This wave theory employs an iterative numerical technique to solve the stream function equation. The stream function describes not only the geometry of a two dimensional flow, but also the components of the velocity vector at any point, and the flow rate between any two streamlines. The most suitable wave theory is dependent on the wave height, the wave period, and the water depth. Based on these parameters, the applicable wave theory can be determined from the figure below (from API-RP2A, American Petroleum Institute - Recommended Practice 2A).

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Applicable Wave Theory Determination The limiting wave steepness for most deep water waves is usually determined by the Miche Limit: H / L = 0.142 tanh( kd ) Where: H is the wave height L

is the wave length

k

is the wave number (2 )/L

d

is the water depth

Pseudo-Static Hydrodynamic Loading CAESAR II allows individual pipe elements to experience loading due to hydrodynamic effects. These fluid effects can impose a substantial load on the piping elements in a manner similar to, but more complex than wind loading. The various wave theories incorporated into CAESAR II as well as the various types of current profiles are discussed below. The wave theories and the current profile are used to compute the water particle velocities and accelerations at the node points. Once these parameters are available, the force on the element can be computed using Morrison’s equation: F = 1/2 *

* Cd * D * U * |U| + /4 *

* Cm * D2 * A

Where - is the fluid density Cd- is the drag coefficient D - is the pipe diameter U - is the particle velocity Cm - is the inertial coefficient A - is the particle acceleration The particle velocities and accelerations are vector quantities which include the effects of any applied waves or currents. In addition to the force imposed by Morrison’s equation, piping elements are also subjected to a lift force and a buoyancy force. The lift force is defined as the force acting normal to the plane formed by the velocity vector and the element’s axis. The lift force is defined as: Fl = 1/2 *

* Cl * D * U2

Where - is the fluid density Cl - is the lift coefficient D - is the pipe diameter U - is the particle velocity

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The buoyancy force acts upward, and is equal to the weight of the fluid volume displaced by the element. Once the force on a particular element is available, it is placed in the system load vector just as any other load is. A standard solution is performed on the system of equations which describe the piping system. (The piping system can be described by the standard finite element equation: [K] {x} = {f} Where [K] - is the global stiffness matrix for the entire system {x} - is the displacement / rotation vector to solve for {f} - is global load vector The element loads generated by the hydrodynamic effects are placed in their proper locations in {f}, similar to weight, pressure, and temperature. Once [K] and {f} are finalized, a standard finite element solution is performed on this system of equations. The resulting displacement vector {x} is then used to compute element forces, and these forces are then used to compute the element stresses.) Except for the buoyancy force, all other hydrodynamic forces acting on the element are a function of the particle velocities and accelerations.

AIRY Wave Theory Implementation Airy wave theory is also known as “linear” wave theory, due to the assumption that the wave profile is symmetric about the mean water level. Standard Airy wave theory allows for the computation of the water particle velocities and accelerations between the mean surface elevation and the bottom. The Modified Airy wave theory allows for the consideration of the actual free surface elevation in the computation of the particle data. CAESAR II includes both the standard and modified forms of the Airy wave theory. To apply the Airy wave theory, several descriptive parameters about the wave must be given. These values are then used to solve for the wave length, which is a characteristic parameter of each unique wave. CAESAR II uses Newton-Raphston iteration to determine the wave length by solving the dispersion relation, shown below: L = (gT2 / 2 ) * tanh(2 D / L) Where g - is the acceleration of gravity T - is the wave period D - is the mean water depth L - is the wave length to be solved for Once the wave length (L) is known, the other wave particulars of interest may be easily determined. The parameters determined and used by CAESAR II are: the horizontal and vertical particle velocities ( UX and UY ), the horizontal and vertical particle acceleration ( AX and AY ), and the surface elevation above (or below) the mean water level ( ETA ). The equations for these parameters can be found in any standard text (such as those listed at the end of this section) which discusses ocean wave theories, and therefore will not be repeated here.

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STOKES Wave Theory Implementation The Stokes wave is a 5th order gravity wave, and hence non-linear in nature. The solution technique employed by CAESAR II is described in a paper published by Skjelbreia and Hendrickson of the National Engineering Science Company of Pasadena California in 1960. The standard formulation as well as a modified formulation (to the free surface) are available in CAESAR II Stokes 5th Order Wave Theory. The solution follows a procedure very similar to that used in the Airy wave, characteristic parameters of the wave are determined by using Newton-Raphston iteration, followed by the determination of the water particle values of interest. The Newton-Raphston iteration procedure solves two non-linear equations for the constants beta and lambda. Once these values are available, the other twenty constants can be computed. After all of the constants are known, CAESAR II can compute: the horizontal and vertical particle velocities ( UX and UY ), the horizontal and vertical particle acceleration ( AX and AY ), and the surface elevation above the mean water level (ETA).

Stream Function Wave Theory Implementation In addition to the forces imposed by ocean waves, piping elements may also be subjected to forces imposed by ocean currents. There are three different ocean current models in CAESAR II; linear, piecewise, and a power law profile. The linear current profile assumes that the current velocity through the water column varies linearly from the specified surface velocity (at the surface) to zero (at the bottom). The piece-wise linear profile employs linear interpolation between specific “depth/velocity” points specified by the user. The power law profile decays the surface velocity to the 1/7 power. While waves produce unsteady flow, where the particle velocities and accelerations at a point constantly change, current produces a steady, non-varying flow.

Ocean Currents In addition to forces imposed by ocean waves, piping elements may also be subjected to forces imposed by ocean currents. There are three different ocean current models in CAESAR II; linear piece-wise linear profile, and a power law profile. The linear current profile assumes that the current velocity though the water column varies linearly from the specified surface velocity (at the surface to zero (at the bottom). The piece-wise linear profile employs linear interpolation between specific "depth /velocity" points specified by the user. The power law profile decays the surface velocity to the 1/7 power. While waves produce unsteady flow, where the particle velocities and accelerations at a point constantly change, current produces a steady, non-varying flow.

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Technical Notes on CAESAR II Hydrodynamic Loading The input parameters necessary to define the fluid loading are described in detail in the next section. The basic parameters describe the wave height and period, and the current velocity. The most difficult to obtain, and also the most important parameters, are the drag, inertia, and lift coefficients, Cd, Cm, and Cl. Based on the recommendations of API RP2A and DNV (Det Norske Veritas), values for Cd range from 0.6 to 1.2, values for Cm range from 1.5 to 2.0. Values for Cl show a wide range of scatter, but the approximate mean value is 0.7. The inertia coefficient Cm is equal to one plus the added mass coefficient Ca. This added mass value accounts for the mass of the fluid assumed to be entrained with the piping element. In actuality, these coefficients are a function of the fluid particle velocity, which varies over the water column. In general practice, two dimensionless parameters are computed which are used to obtain the Cd, Cm, and Cl values from published charts. The first dimensionless parameter is the Keulegan-Carpenter Number, K. K is defined as: K = Um * T / D Where: Um - is the maximum fluid particle velocity T - is the wave period D - is the characteristic diameter of the element. The second dimensionless parameter is the Reynolds number, Re. Re is defined as Re = Um * D / Where: Um - is the maximum fluid particle velocity D - is the characteristic diameter of the element. - is the kinematic viscosity of the fluid (1.26e-5 ft2/sec for sea water).

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Once K and Re are available, charts are used to obtain Cd, Cm, and Cl. (See Mechanics of Wave Forces on Offshore Structures by T. Sarpkaya, Figures 3.21, 3.22, and 3.25 for example charts, which are shown in the figures below.)

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In order to determine these coefficients, the fluid particle velocity (at the location of interest) must be determined. The appropriate wave theory is solved, and these particle velocities are readily obtained. Of the wave theories discussed, the modified Airy and Stokes 5th theories include a modification of the depth-decay function. The standard theories use a depth-decay function equal to cosh(kz) / sinh(kd), Where: k - is the wave number, 2 /L L - is the wave length d - is the water depth z - is the elevation in the water column where the data is to be determined The modified theories include an additional term in the numerator of this depth-decay function. The modified depth-decay function is equal to cosh( d) / sinh(kd), Where: - is equal to z / (d + #)

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The term d represents the effective height of the point at which the particle velocity and acceleration are to be computed. The use of this term keeps the effective height below the still water level. This means that the velocity and acceleration computed are convergent for actual heights above the still water level. As previously stated, the drag, inertia, and lift coefficients are a function of the fluid velocity and the diameter of the element in question. Note that the fluid particle velocities vary with both depth and position in the wave train (as determined by the applied wave theory). Therefore, these coefficients are in fact not constants. However, from a practical engineering point of view, varying these coefficients as a function of location in the Fluid field is usually not implemented. This practice can be justified when one considers the inaccuracies involved in specifying the instantaneous wave height and period. According to Sarpkaya, these values are insufficient to accurately predict wave forces, a consideration of the previous fluid particle history is necessary. In light of these uncertainties, constant values for Cd, Cm, and Cl are recommended by API and many other references. The effects of marine growth must also be considered. Marine growth has the following effects on the system loading: the increased pipe diameters increase the hydrodynamic loading; the increased roughness causes an increase in Cd, and therefore the hydrodynamic loading; the increase in mass and added mass cause reduced natural frequencies and increase the dynamic amplification factor; it causes an increase in the structural weight; and possibly causes hydrodynamic instabilities, such as vortex shedding. Finally, Morrison’s force equation is based the “small body” assumption. The term “small” refers to the “diameter to wave length” ratio. If this ratio exceeds 0.2, the inertial force is no longer in phase with the acceleration of the fluid particles and diffraction effects must be considered. In such cases, the fluid loading as typically implemented by CAESAR II is no longer applicable. Additional discussions on hydrodynamic loads and wave theories can be found in the references at the end of this article.

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Input: Specifying Hydrodynamic Parameters in CAESAR II The hydrodynamic load analysis requires the specification of several measurable parameters which quantify the physical aspects of the environmental phenomenon in question. Note: Users can enter four different wave loads here. Use the Editing Load Case buttons to move up or down between the Wave Load Input Spreadsheets. The necessary hydrodynamic parameters are discussed in the following paragraphs and a CAESAR II hydrodynamic loading dialog is shown in the figure below.

Wave Loading Editing in the Load Case Editor

Current Data Profile Type—This entry defines the interpolation method used by CAESAR II to determine the current velocity as a function of depth. Available options for this entry are: a power law profile, a piece-wise linear profile, and a linear profile. The power law profile determines the current velocity at depth D according to the equation: Vd = Vs * [di / D]p Where Vd - is the velocity at depth di Vs - is the specified velocity at the surface D - is the water depth p - is the power, set to 1/7

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The piece-wise linear profile performs a linear interpolation of a velocity verse depth table (provided by the user) to obtain the current velocity at depth di. When this type profile is specified, a table of depths and velocities must be provided. The table should start at the surface (a depth of zero) and progress in the direction of increasing depth, to the sea bed. The linear profile also performs a linear interpolation to obtain the current velocity at depth di. However, this method assumes the current velocity varies linearly from the specified surface velocity to zero at the sea bed. Current Speed — This entry defines the current speed at the surface. The units for this entry are (length/time) as defined by the active units file at the time of input. This value should always be a positive entry. Current Direction Cosines — These entries define the direction of fluid transport due to the current. These fields are unitless, and follow the standard software global axis convention.

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Wave Data Wave Theory Indicator — This entry specifies which wave theory is to be used to compute the water particle velocities and accelerations. The wave theories presently available are: Standard Airy Wave — This is also known as linear wave theory. Discussion of this theory can be found in the previously mentioned references. Modified Airy Wave — This is a modification of the standard Airy theory which includes the free surface effects due to the wave. The modification consists of determining a depth scaling factor equal to the depth divided by the depth plus the surface elevation. Note that this scale factor varies as a function of the location in the wave train. Standard Stokes 5th Wave — This is a 5th order wave theory, also discussed in the previously mentioned references. Modified Stokes 5th Wave — This is a modification of the standard Stokes 5th theory. The modification is the same as applied to the Airy theory. Stream Function Wave — This is Dean’s Stream Function theory, also discussed in the previously mentioned references. Modified Stream Function Wave — This is Dean’s Stream Function theory, modified to directly consider current in the wave solution. Stream Function Order — When the Stream Function theory is activated, the solution order must be defined. Typical values for the stream function order range from 3 to 13 (see API-RP2A figure). Water Depth — This entry defines the vertical distance (in units of length) from the still water level (the surface) to the sea bed. Wave Height — This entry defines the height of the incident wave. The height is the vertical distance (in units of length) from the wave crest to the wave trough. Wave Period — This entry defines the time span (in seconds) for two successive wave crests to pass a fixed point. Wave Kinematic Factor — Because the two dimensional wave theories do not account for spreading, a reduction factor is often used for the horizontal particle velocity and acceleration. Wave kinematic measurements support values in the range of 0.85 to 0.95. Refer to the applicable offshore codes before using this item. Wave Direction Cosines — These entries define the direction of wave travel. These fields are unitless, and follow the standard software global axis convention. Wave Phase Angle — This entry defines the position of the wave relative to the starting node of the piping system. The phase angle is a measure (in degrees) of position in the wave train, where 0 is the wave crest, 180 is the wave trough, and 360 is the following crest. Since the wave propagates over the piping structure, each point in the structure experiences all possible wave phase angles. One analysis technique specifies the wave phase at the system origin, and then the phase at each node point in the model is determined. From these exact phase locations, the water particle data is computed from the wave theory.

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Alternatively, a conservative engineering approach is to use the same phase angle (usually zero) for all points in the model. This technique produces higher loads, however, the extra conservatism is warranted when given the unknowns in specifying environmental data.

Seawater Data Free Surface Elevation — This entry defines the height of the free surface, from the global system origin. If the system origin is at the free surface, this entry should be specified as zero. If the system origin is at the sea bottom, this entry is equal to the water depth. By default, the first node in a CAESAR II model is at an elevation of zero. This elevation can be changed using the [Alt-G] key sequence. Kinematic Viscosity — This entry is used to define the kinematic viscosity of water. This value is used to determine the Reynolds number, which is subsequently used to determine they hydrodynamic coefficients Cd, Cm, and Cl. Typical values of kinematic viscosity for sea water are listed in the table below. Temp Deg (F)

(ft2/sec)

Temp (C)

(m2/sec)

60

1.26e-5

15.556

1.17058e-6

50

1.46e-5

10.000

1.35639e-6

40

1.55e-5

4.444

1.44000e-6

30

2.00e-5

-1.111

1.85807e-6

Fluid Weight Density - This entry defines the weight density of the fluid. For sea water, this value is approximately .037037 pounds per cubic inch (.001025 kg/cm3, 1.0256SG).

Piping Element Data Element Exposure — In implementing hydrodynamic loading in a software program, one must be able to indicate that elements are either exposed to the fluid or not exposed to the fluid. In CAESAR II, this is accomplished by a set of “radio buttons,” which indicate that the particular element is exposed to hydrodynamic loads, wind loads, or not exposed. This specification carries forward for all subsequent elements, until changed. Hydrodynamic Coefficients — Piping elements which are to be subjected to hydrodynamic loading must have a drag (Cd), an inertia (Cm), and a lift (Cl) coefficient defined. The specification of these items is optional. A user may specify these values as constants to be applied to all subsequent exposed elements, regardless of depth or phase position in the wave. Alternatively, these values may be left blank, which will cause CAESAR II to interpolate their values from the charts previously discussed. Marine Growth — This entry defines the amount of marine growth on the piping elements. The value of this entry is used to increase the diameter of the piping elements. The units for this field are the current diameter units. The diameter used in the computation of the hydrodynamic forces is equal to the pipe diameter plus twice the marine growth entry.

References 1

Mechanics of Wave Forces On Offshore Structures, Turgut Sarpkaya and Michael Isaacson, Van Nostrand Reinhold Co., 1982, ISBN 0-442-25402-4.

2

Handbook of Ocean and Underwater Engineering, Myers, Holm, and McAllister, McGraw-Hill Book Co., 1969, ISBN 07-044245 -2.

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3

Fifth Order Gravity Wave Theory, Lars Skjelbreia and James Hendrickson, National Engineering Science Co., Pasadena, California, 1960.

4

Planning and Design of Fixed Offshore Platforms, McClelland and Reifel, Van Nostrand Reinhold Co., 1986, ISBN 0-442-25223-4.

5

Intercomparison of Near-Bottom Kinematics by Several Wave Theories and Field and Laboratory Data, R. G. Dean and M. Perlin, Coastal Engineering, #9 (1986), p399-437.

6

A Finite Amplitude Wave on a Linear Shear Current, R. A. Dalrymple, Journal of Geophysical Research, Vol 79, No 30, 1974.

7

Application of Stream Function Wave Theory to Offshore Design Problems, R. G. Dean, OTC #1613, 1972.

8

Stream Function Representation of Nonlinear Ocean Waves, R. G. Dean, Journal of Geophysical Research, Vol 70, No 18, 1965.

9

American Petroleum Institute - Recommended Practice 2A (API-RP2A), American Petroleum Institute, July 1993.

10 Improved Algorithm for Stream Function Wave Theory, Min-Chih Huang, Journal of Waterway, Port, Coastal, and Ocean Engineering, January 1989. 11 Stream Function Wave Theory with Profile Constraints, Min-Chih Huang, Journal of Waterway, Port, Coastal, and Ocean Engineering, January/February 1993.

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Evaluating Vessel Stresses The ASME Section VIII, Division 2 code provides for a fairly elaborate procedure to analyze the local stresses in vessels and nozzles. Only the elastic analysis approach will be discussed in this manual. The user should always refer to the applicable code if any of the limits described in this section are approached, or if any unusual material, weld, or stress situation exists, or there are non-linear concerns such as the material's operation in the creep range. The first step in the procedure is to determine if the elastic approach is satisfactory. Section AD-160 contains the exact method and basically states that if all of the following conditions are met, then fatigue analysis need not be done: 1

The expected design number of full-range pressure cycles does not exceed the number of allowed cycles corresponding to an Sa value of 3Sm (4Sm for non-integral attachments) on the material fatigue curve. The Sm is the allowable stress intensity for the material at the operating temperature.

2

The expected design range of pressure cycles other than startup or shutdown must be less than 1/3 (1/4 for non-integral attachments) the design pressure times (Sa/Sm), where Sa is the value obtained on the material fatigue curve for the specified number of significant pressure fluctuations.

3

The vessel does not experience localized high stress due to heating.

4

The full range of stress intensities due to mechanical loads (including piping reactions) does not exceed Sa from the fatigue curve for the expected number of load fluctuations.

Once the user has decided that an elastic analysis will be satisfactory, either a simplified or a comprehensive approach may be taken to the vessel stress evaluation. Both methods will be described in detail below, after a discussion of the Section VIII Div. 2 Requirements.

ASME Section VIII Division 2 - Elastic Analysis of Nozzle Ideally, in order to address the local allowable stress problem, the user should have the endurance curve for the material of construction and complete design pressure / temperature loading information. If any of the elastic limits are approached, or if there is anything out of the ordinary about the nozzle/vessel connection design, the code should be carefully consulted before performing the local stress analysis. The material Sm table and the endurance curve for carbon steels are given in this section for illustration. Only values taken directly from the code should be used in design. There are essentially three criteria that must be satisfied before the stresses in the vessel wall due to nozzle loads can be considered within the allowables. These three criteria can be summarized as: Pm < kSmh Pm + Pl + Pb< 1.5kSmh Pm + Pl + Pb + Q < 3Smavg

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Where Pm, Pl, Pb, and Q are the general primary membrane stress, the local primary membrane stress, the local primary bending stress, and the total secondary stresses (membrane plus bending), respectively; and K, Smh, and Smavg are the occasional stress factor, the hot material allowable stress intensity, and the average material stress intensity (Smh + Smc) / 2. Due to the stress classification defined by Section VIII, Division 2 in the vicinity of nozzles, as given in the Table 4-120.1, the bending stress terms caused by any external load moments or internal pressure in the vessel wall near a nozzle or other opening, should be classified as Q, or the secondary stresses, regardless of whether they were caused by sustained or expansion loads. This causes Pb to disappear, and leads to a much more detailed classification: Pm—General primary membrane stress (primarily due to internal pressure) Pl—Local primary membrane stress, which may include --Membrane stress due to internal pressure --Local membrane stress due to applied sustained forces and moments Q—Secondary stresses, which may include --Bending stress due to internal pressure --Bending stress due to applied sustained forces and moments --Membrane stress due to applied expansion forces --Bending stress due to applied expansion forces and moments --Membrane stress due to applied expansion moments Each of the stress terms defined in the above classifications contain three parts: two stress components in normal directions and one shear stress component. To combine these stresses, the following rules apply: Compute the normal and shear components for each of the three stress types, i.e. Pm, Pl, and Q; Compute the stress intensity due to the Pm and compare it against kSmh; Add the individual normal and shear stress components due to Pmand Pl; compute the resultant stress intensity and compare its value against 1.5kSmh; Add the individual normal and shear stress components due to Pm, Pl, and Q, compute the resultant stress intensity, and compare its value to against 3Smavg. If there is an occasional load as well as a sustained load, these types may be repeated using a k value of 1.2. These criteria can be readily found from Figure 4-130.1 of Appendix 4 of ASME Section VIII, Division 2 and the surrounding text. Note that the primary bending stress term, Pb, is not applicable to the shell stress evaluation, and therefore disappears from the Section VIII, Division 2 requirements. Under the same analogy, the peak stress limit may also be written as: Pl + Pb + Q + F < S a The preceding equation need not be satisfied, provided the elastic limit criteria of AD-160 is met based on the statement explicitly given in Section 5-100, which is cited below: “If the specified operation of the vessel meets all of the conditions of AD-160, no analysis for cyclic operation is required and it may be assumed that the peak stress limit discussed in 4-135 has been satisfied by compliance with the applicable requirements for materials, design, fabrication, testing and inspection of this division.”

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Procedure to Perform Elastic Analyses of Nozzles The procedure for checking stresses in vessel shells using WRC 107 can be summarized as follows: 1

Check geometric limitation to see whether WRC 107 is applicable;

2

If yes, check to see whether or not the elastic approach as outlined in Section VIII, Division 2, AD160 is satisfactory;

3

Compute the sustained, expansion and occasional loads in the vessel shell due to the applied nozzle loads. Consider the local restraint configuration in order to determine whether or not the axial pressure thrust load (P * Ain) should be added to the sustained (and occasional loads). If desired by the user, this thrust load will be automatically calculated and added to the applied loads.

4

Calculate pressure stresses, Pm, on the vessel shell wall in both longitudinal and circumferential (hoop) directions for both sustained and occasional cases. Notice that two different pressure terms are required in carrying out the pressure stress calculations. P is the design pressure of the system (sustained), while Pvar is the DIFFERENCE between the peak pressure and the design pressure of the system, which will be used to qualify the vessel membrane stress under the occasional load case.

Note:

The Pm stresses will be calculated automatically if a pressure value is enter by the user.

1

Run WRC 107 to calculate the Pl, and Q stresses as defined earlier. Note that the local stresses due to sustained, expansion and occasional loads can now be compute simultaneously.

2

Various stress components can be obtained from combining the stress intensities computed from applying the sustained, expansion and occasional loads, if applicable. These stress intensities can then be used to carry out the stress summations and the results are used to determine acceptability of the local stresses in the vessel shell. Notice now CAESAR II can provide the WRC 107 stress summation module in line with the stress calculation routines

Under the above procedure, the equations used in CAESAR II to qualify the various stress components can be summarized as follows: Pm(SUS) < Smh Pm(SUS + OCC) < 1.2Smh Pm(SUS) + Pl(SUS) < 1.5Smh Pm(SUS + OCC) + Pl(SUS + OCC) < 1.5(1.2)Smh Pm(SUS + OCC) + Pl(SUS + OCC) + Q(SUS + EXP + OCC) < 1.5(Smc + Smh)

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Description of Alternate Simplified ASME Sect. VIII Div. 2 Nozzle Analysis The most difficult problem associated with the comprehensive ASME Sect. VIII, Div. 2 nozzle/vessel analysis involves the pressure calculation. Hoop and longitudinal hand pressure calculations can not be considered dependable, and axial pressure loading on the junction is often calculated incorrectly or omitted. A smaller, yet significant problem with the comprehensive calculation is the time it takes to organize and manipulate the stress data. For these reasons, an alternate simplified approach was developed. To eliminate the concern for pressure, both the pressure term in the loading on the left side of the inequality and the pressure term in the allowable on the right side of the inequality are cancelled. The first check is Pm (due to pressure) must be less than or equal to 1.0 Smh. Assuming that the area reinforcement around the nozzle will satisfy the pressure requirements, let this first check equal the maximum value. The second check is Pm + Pl + Pb must be less than or equal to 1.5 Smh. Subtracting the stresses due to pressure (assumed equal to Smh) reduces this check to: Pl + Pb (due to external sustained forces without pressure) < 0.5 Smh. Unfortunately, the third check on the Pm + Pl + Q terms are at the root of an application controversy. There are primarily three schools of thought: Pm+Pl+Q is an operating loading condition, and as such, includes the loads due to pressure and weight. Pm+Pl+Q is the range of loads, i.e. the expansion loading condition, and as such, excludes the effects of sustained, or primary loads. Primary sustained loads, such as weight and pressure, should be excluded. Pm+Pl+Q is the range of loads and should exclude the primary load weight, but should include the varying pressure load at least in those thermal load cases where the system goes from a startup (ambient temperature and pressure condition to operating condition). For the simplification, it is assumed that the Pm component due to pressure should be included in both the left and right side of the Pm+Pl+Pb+Q < 3Sm inequality, thus assuming that the area reinforcement requirements are exactly satisfied, i.e. Again, letting Pm = Sm and subtracting this pressure term from the “expansion” allowable (Pm + Pl + Q < 3Sm) provides a simplified allowable limit. The expansion (or operating, or both) loads from the CAESAR II restraint report should satisfy the computed stress requirement: Pl + Pb + Q (operating or expansion excluding pressure) < 2Sm. In summary Ensure proper nozzle reinforcement for pressure and assume pressure stresses are at their maximum. Compare primary stresses (without pressure) to 1/2 Smh. Compare stresses due to the sum of primary and secondary loads to 2Sm(avg); where Sm(avg) is the average of the hot and cold allowable stress intensities (Smh & Smc).

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Simplified ASME Sect. VIII Div. 2 Elastic Nozzle Analysis 1

Perform a CAESAR II analysis of the piping loads on the vessel/nozzle junction. Use WRC 297 flexibilities to compute loads more accurately, but less conservatively (or do two analysis, one with flexibilities and one without). From this analysis the user should have sustained, operating, and expansion loads on the vessel/nozzle junction.

2

Find Smh and Smc from the Sect. VIII allowable stress tables. Smh is the vessel material hot allowable, and Smc is the vessel material cold allowable.

3

Run WRC 107 with the sustained loads on the vessel/nozzle junction from CAESAR II, and make sure that the computed stress intensities are less than 0.5 Smh. This conservatively considers bending stresses from internal pressure and sustained moments to have a primary classification; if it fails, the stresses must be reviewed in more detail.

4

Run WRC 107 with the operating loads on the vessel/nozzle junction from CAESAR II, and make sure that the computed stress intensities are less than Smh + Smc.

5

Run WRC 107 with the expansion loads on the vessel/nozzle junction from CAESAR II, and make sure that the computed stress intensities are less than Smh + Smc.

Should any of the checks described fail, then the more comprehensive analysis (described earlier) of the junction should be performed.

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Inclusion of Missing Mass Correction The response of a system under a dynamic load is often determined by superposition of modal results, with CAESAR II specifically providing the spectral analysis method for use. One of the advantages of modal analysis is that usually only a limited number of modes are excited and need be included in the analysis. The drawback to this method is that although displacements may be obtained with good accuracy using only a few of the lowest frequency modes, the force, reaction, and stress results may require extraction of far more modes (possibly far into the rigid range) before acceptable accuracy is attained. CAESAR II’s Missing Mass option offers the ability to include a correction which represents the quasistatic contribution of the higher order modes not explicitly extracted for the modal/dynamic response, thus providing greater accuracy with reduced calculation time. The dynamic response of a linear multi-degree-of-freedom system is described by the following equation: Ma(t) + Cv(t) + Kx(t) = F(t) Where: M = n x n mass matrix of system C = n x n damping matrix of system K = n x n stiffness matrix of system a(t) = n x 1, time-dependent acceleration vector v(t) = n x 1, time-dependent velocity vector x(t) = n x 1, time-dependent displacement vector F(t) = n x 1, time-dependent applied force vector Assuming harmonic motion and neglecting damping, the free vibration eigenvalue problem for this system is K% - M%

2

=0

Where: % = n x n mode shape matrix 2

= n x n matrix where each diagonal entry is the frequency squared of the corresponding mode

The modal matrix % may be normalized such that %T M % = I (where I is the n x n identity matrix) and %T K % = 2. The modal matrix % may be partitioned into two submatrices: % = [ %e %r ] Where: %e = mode shapes extracted for dynamic analysis (i.e., lowest frequency modes) %r = residual (non-extracted) mode shapes (corresponding to rigid response, or the “missing mass” contribution)

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The extracted mode shapes are orthogonal to the residual mode shapes, or: %eT x %r = 0 The displacement components can be expressed as linear combinations of the mode shapes: x = %Y = %e Ye + %r Yr = xe + xr Where: x = total system displacements xe = system displacements due to extracted modes xr = system displacements due to residual modes Y = generalized modal coordinates Ye = partition of Y matrix corresponding to extracted modes Yr = partition of Y matrix corresponding to residual modes The dynamic load vector can be expressed in similar terms: F = K % Y = K %e Ye + K %r Yr = Fe + Fr Where: F = total system load vector Fe = load vector due to extracted modes Fr = load vector due to residual modes Y = generalized modal coordinates Ye = partition of Y matrix corresponding to extracted modes Yr = partition of Y matrix corresponding to residual modes Normally, modal superposition analyses completely neglect the rigid response — the displacements X r caused by the load Fr. This response, of the non-extracted modes, can be obtained from the system displacement under a static loading Fr. Based upon the relationships stated above, Fr can be estimated as follows: F = K % e Ye + K % r Yr Multiplying both sides by %eT (and considering that %eT %r = 0): %eT F = %eT K %e Ye + %eT K %r Yr = %eT K %e Ye 2 e

for %eT K %e and solving for Ye:

%eT F =

2 e

Ye

Ye = %eT

-2 e

Substituting

F

The residual force can now be stated as Fr = F - K %e Ye = F - %eT K %e

-2 e

F

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As seen earlier %T M %

2

=I

2

Substituting %eT M%e Fr = F - %eT M %e

= %T K % 2 e

for %eT K %e:

2 e

-2 e

F = F - %eT M %e F

Therefore, CAESAR II calculates the residual response (and includes it as the missing mass contribution) according to the following procedure: 1

The missing mass load is calculated for each individual shock load as

Fr = F - %eT M %e F Note: The load vector F represents the product of the force set vector and the rigid DLF for force spectrum loading; the product of the mass matrix, ZPA, and directional vector for non-ISM seismic loads; and the product of the mass matrix, ZPA, and displacement matrix (under unit ISM support displacement) for seismic anchor movement loads. Note that the missing mass load will vary, depending upon the number of modes extracted by the user and the cutoff frequency selected (or more specifically, the DLF or acceleration corresponding to the cutoff frequency). "Rigid,” for the purposes of determining the rigid DLF, or the ZPA, may be designated by the user, through a setup parameter, to be either the DLF/acceleration associated with the frequency of the last extracted mode, or the true spectral DLF/ ZPA—that corresponding to the largest entered frequency of the input spectrum. 2

The missing mass load is applied to the structure as a static load. The static structural response is then combined (according to the user-specified combination method) with the dynamically amplified modal responses as if it were a modal response. Actually this static response is the algebraic sum of the responses of all non-extracted modes— representing in-phase response, as would be expected from rigid modes.

3

The Missing Mass Data report is compiled for all shock cases, whether missing mass is to be included or not. The percent of mass active is calculated according to: % Active Mass = 1 - ( Fr[i] / summed over i = 1 to n

F [i])

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The maximum possible percent that is theoretically possible for this value is of course 100%, however numerical inaccuracies may occasionally cause the value to be slightly higher. If the missing mass correction factor is included, the percent of mass included in the correction is shown in the report as well. Since CAESAR II’s procedure assumes that the missing mass correction represents the contribution of rigid modes, and that the ZPA is based upon the spectral ordinate value at the frequency of the last extracted mode, it is recommended that the user extract modes up to, but not far beyond, a recognized “rigid” frequency. Choosing a cutoff frequency to the left of the spectrum’s resonant peak will provide a nonconservative result, since resonant responses may be missed. Using a cutoff frequency to the right of the peak, but still in the resonant range, will yield conservative results, since the ZPA/rigid DLF will be overestimated. Extracting a large number of rigid modes for calculation of the dynamic response may be conservative, since all available modal combination methods (SRSS, GROUP, ABS, etc.) give conservative results versus the algebraic combination method which gives a more realistic representation of the net response of the rigid modes. Based upon the response spectrum shown below, an appropriate cutoff point for the modal extraction would be about 33 Hz.

CAESAR II provides two options for combining the missing mass correction with the modal (dynamic) results—SRSS and Absolute. The Absolute combination method of course provides the more conservative result, and is based upon the assumption that the dynamic amplification is going to occur simultaneously with the maximum ground acceleration or force load. Literature (References 1, 2) states that the modal and the rigid portions of the response to typical dynamic loads are actually statistically independent, so that an SRSS combination method is a more accurate representation of reality. For this reason, CAESAR II’s default missing mass combination method is SRSS.

References 1

A. K. Gupta, Response Spectrum Method in Seismic Analysis and Design of Structures, CRC Press, 1990

2

K. M. Vashi, “Computation of Seismic Response from Higher Frequency Modes,” ASME 80C2/PVP-50, 1980

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3

53

O. E. Hansteen and K. Bell, “On the Accuracy of Mode Superposition Analysis in Structural Dynamics,” Earthquake Engineering and Structural Dynamics, Volume 7, John Wiley & Sons, Ltd., 1979

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Fatigue Analysis Using CAESAR II For most piping codes supported by CAESAR II, performance of fatigue analysis is an extension to, rather than an explicit part of, the code requirements (however, it is an explicit part of the IGE/TD/12 Pipework Stress Analysis for Gas Industry Plant code).

Fatigue Basics Piping and vessels have been known to suffer from sudden failure following years of successful service. Research done during the 1940s and 1950s (primarily advanced by A. R. C. Markl’s “Piping Flexibility Analysis,” published in 1955) provided an explanation for this phenomenon, as well as design criteria aimed at avoiding failures of this type. The explanation was that materials were failing due to fatigue, a process leading to the propagation of cracks, and subsequent fracture, following repeated cyclic loading. Steels and other metals are made up of organized patterns of molecules, known as crystal structures. However, these patterns are not maintained throughout the steel producing an ideal homogeneous material, but are found in microscopic isolated island-like areas called grains. Inside each grain the pattern of molecules is preserved. From one grain boundary to the next the molecular pattern is the same, but the orientation differs. As a result, grain boundaries are high energy borders. Plastic deformation begins within a grain that is both subject to a high stress and oriented such that the stress causes a slippage between adjacent layers in the same pattern. The incremental slippages (called dislocations) cause local cold-working. On the first application of the stress, dislocations will move through many of the grains that are in the local area of high stress. As the stress is repeated, more dislocations will move through their respective grains. Dislocation movement is impeded by the grain boundaries, so after multiple stress applications, the dislocations tend to accumulate at grain boundaries, eventually becoming so dense that the grains “lock up,” causing a loss of ductility and thus preventing further dislocation movement. Subsequent applications of the stress cause the grain to tear, forming cracks. Repeated stress applications cause the cracks to grow. Unless abated, the cracks propagate with additional stress applications until sufficient cross sectional strength is lost to cause catastrophic failure of the material. The fatigue capacity of a material can be estimated through the application of cyclic tensile/compressive displacement loads with a uniaxial test machine. A plot of the cyclic stress capacity of a material is called a fatigue (or endurance) curve. These curves are generated through multiple cyclic tests at different stress levels. The number of cycles to failure usually increases as the applied cyclic stress decreases, often until a threshold stress (known as the endurance limit) is reached below which no fatigue failure occurs, regardless of the number of applied cycles. An endurance curve for carbon and low alloy steels, taken from the ASME Section VIII Division 2 Pressure Vessel Code is shown in the following figure.

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Fatigue Analysis of Piping Systems The IGE/TD/12 code does, on the other hand, present specific requirements for true fatigue evaluation of systems subject to a cyclic loading threshold. Furthermore, ASME Section III, Subsection NB and ASME Section VIII Division 2 provide guidelines by which fatigue evaluation rules may be applied to piping (and other pressure retaining equipment). These procedures have been adapted, where possible, to CAESAR II’s methodology.

To perform fatigue analyses: 1

Assigning fatigue curve data to the piping material: This is done on the Allowable auxiliary screen. Fatigue data may be entered directly, or read in from a text file (a number of commonly used curves have been provided). Users may define their own fatigue curves as defined later in this section.

2

Defining the fatigue load cases: This may be done in either the static or dynamic load case builders. For this purpose, a new stress type, FAT, has been defined. For every fatigue case, the number of anticipated cycles must also be defined.

3

Calculation of the fatigue stresses: This is done automatically by CAESAR II – the fatigue stresses, unless explicitly defined by the applicable code are calculated the same as CAESAR II calculates stress intensity, in order to conform to the requirements of ASME Section VIII, Division 2 Appendix 5. (The IGE/TD/12 is currently the only piping code supported by CAESAR II which does have explicit instructions for calculating fatigue stresses.) The equations used in the calculation of fatigue stresses are documented at the end of this section.

4

Determination of the allowable fatigue stresses: Allowables are interpolated logarithmically from the fatigue curve based upon the number of cycles designated for the load case. For static load cases, the calculated stress is assumed to be a peak-to-peak cyclic value (i.e., thermal expansion, settlement, pressure, etc.), so the allowable stress is extracted directly from the fatigue curve. For harmonic and dynamic load cases, the calculated stress is assumed to be a zero-to-peak cyclic value (i.e., vibration, earthquake, etc.), so the extracted allowable is divided by 2 prior to use in the comparison.

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5

Determination of the allowable number of cycles: The flip side of calculating the allowable fatigue stress for the designated number of cycles is the calculation of the allowable number of cycles for the calculated stress level. This is done by logarithmically interpolating the “Cycles” axis of the fatigue curve based upon the calculated stress value. Since static stresses are assumed to be peak-to-peak cyclic values, the allowable number of cycles is interpolated directly from the fatigue curve. Since harmonic and dynamic stresses are assumed to be zero-to-peak cyclic values, the allowable number of cycles is interpolated using twice the calculated stress value.

6

Reporting the results: CAESAR II provides two reports for viewing the results of load cases of stress type FAT. The first of these is the standard stress report, which displays the calculated fatigue stress and fatigue allowable at each node. Stress reports may be generated individually for each load case, and show whether any of the individual load cases in isolation would fail the system.

However, in those circumstances where there is more than one cyclic load case potentially contributing to fatigue failure, the Cumulative Usage report is appropriate. In order to generate this report, the user selects all of the FAT load cases which contribute to the overall system degradation. The Cumulative Usage report lists for each node point the usage ratio (actual cycles divided by allowable cycles), and then sums these up for total Cumulative Usage. A total greater than 1.0 indicates a potential fatigue failure.

Static Analysis Fatigue Example Consider a sample job that potentially has several different cyclic load variations: 1

Operating cycle from ambient (70°F) to 500°F (12,000 cycles anticipated)

2

Shut down external temperature variation from ambient (70°F) to -20°F (200 cycles anticipated)

3

Pressurization to 1800 psig (12,000 cycles anticipated)

4

Pressure fluctuations of plus/minus 30 psi from the 1800 psig (200,000 cycles anticipated)

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57

In order to do a proper fatigue analysis, these should be grouped in sets of load pairs which represent the worst-case combination of stress ranges between extreme states. These load variations can be laid out in graphical form. The figure below shows a sketch of the various operating ranges this system experiences. Each horizontal line represents an operating range. At the each end of each horizontal line, the temperatures and pressures defining the range are noted. At the center of each horizontal line, the number of cycles for each range is defined.

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Using this sketch of the operating ranges, the four fatigue load cases can be determined. The procedure is as follows. Case 1: Cover the absolute extreme, from –20°F and 0 psi to 500°F and 1830 psi. This occurs 200 times. As a result of this case, the cycles for the ranges defined must be reduced by 200. The first range (-20,0 to 70,0) is reduced to zero, and has no contribution to additional load cases. The second range (70,0 to 500,1800) is reduced to 11,800 cycles. The third and fourth ranges are similarly reduced to 199,800 cycles. These same steps can be used to arrive at cases 2 through 4, reducing the number of “considered” cycles at each step. This procedure is summarized in the table below. Segment

-20, 0 to 70, 0

70, 0 to 500, 1800

500, 1700 to 500, 1800

500, 1800 to 500, 1830

Initial

200

12,000

200, 000

200,000

After 1

0

11,800

200, 000

199,800

After 2

0

0

200, 000

188,000

After 3

0

0

12,000

0

After 4

0

0

0

0

Case

This table is then used to set the load cases as cycles between the following load values: Between -20°F, 0 psig and 500°F, 1830 psig (200 cycles) Between 70°F, 0 psig and 500°F, 1830 psig (11,800 cycles) Between 500°F, 1770 psig and 500°F, 1830 psig (188,000 cycles) Between 500°F, 1770 psig and 500°F, 1800 psig (12,000 cycles) These temperatures and pressures are entered as operating conditions accordingly:

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59

Static Analysis Fatigue Example

It is next necessary to enter the fatigue curve data for the material. This is done by clicking the Fatigue Curves… button, revealing the Material Fatigue Curve dialog box. This can be used to enter the fatigue curve for the material (note: for the IGE/ TD/12 code it is necessary to enter five sets of fatigue curves, for fatigue classes D, E, F, G, and W). Up to eight Cycle vs. Stress data points may be entered to define the curve; interpolations are made logarithmically. Cycle/Stress pairs should be entered in ascending order (ascending by cycles). Stress values should be entered as allowable Stress Range, rather than allowable Stress Amplitude.

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Material Fatigue Curves Dialog

Fatigue curves may be alternatively acquired from a text file, by clicking on the Read from file… button. This displays a list of all \CAESAR\SYSTEM\*.FAT files.

Read from File Dialog

Shipped with the program are the following fatigue curve files (the user may easily construct additional fatigue curve files, as described in Appendix A below): 5-110-1A.FAT

ASME Section VIII Division 2 Figure 5-110.1, UTS < 80 ksi

5-110-1B.FAT

ASME Section VIII Division 2 Figure 5-110.1, UTS = 115-130 ksi

5-110-2A.FAT

ASME Section VIII Division 2 Figure 5-110.2, Curve A

5-110-2B.FAT

ASME Section VIII Division 2 Figure 5-110.2, Curve B

5-110-2C.FAT

ASME Section VIII Division 2 Figure 5-110.2, Curve C

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61

In this case, for A106B low carbon steel, operating at 500°F, 5-110-1A.FAT is the appropriate selection. This fills in the fatigue curve data:

A106B Low Carbon Steel Example Fatigue Curve Data

At this point, the job can be error checked, and the load cases can be set up. The static load case builder offers a new stress type, FAT (fatigue). Selecting this stress type does the following: 1

invites the user to define the number of cycles for the load case (dragging the FAT stress type into the load case or pressing the Load Cycles button opens the Load Cycles field),

2

causes the stress range to be calculated as per the fatigue stress method of the governing code (currently this is stress intensity for all codes except IGE/TD/12),

3

causes the calculated stress range to be compared to the full value extracted from the fatigue curve, and

4

indicates that the load case may be included in the Cumulative Usage report.

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The last four load cases represent the load set pairs defined earlier.

Example with Fatigue Load Cases Defined in the Load Case Editor

Once the job has been run, note that the presence of a FAT stress type adds the Cumulative Usage report to the list of available reports.

Static Output Processor

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63

The fatigue stress range may be checked against the fatigue curve allowable for each load case by simply selecting it along with the Stresses report. Review of each load case shows that all stress levels pass.

Example of a Fatigue Stress Report

However, this is not a true evaluation of the situation, because it is not a case of “either-or.” The piping system is subjected to all of these load cases throughout its expected design life, not just one of them. Therefore, we must review the Cumulative Usage report, which shows the total effect of all fatigue load cases (or any combination selected by the user) on the design life of the system. This report lists for each load case the expected number of cycles, the allowable number of cycles (based upon the calculated stress), and the Usage Ratio (actual cycles divided by allowable cycles). The Usage Ratios are then summed for all selected load cases; if this sum exceeds 1.0, the system has exceeded its fatigue capabilities. In this case, it is apparent that the sum of all of the cyclic loadings at node 115 can be expected to fail this system:

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Cumulative Usage Report

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65

Fatigue Capabilities in Dynamic Analysis Fatigue analysis capability is also available for harmonic and dynamic analyses as well. Harmonic load cases are entered as they always have been; they may be designated as being stress type FAT simply by entering the number of expected load cycles on the harmonic input screen:

Harmonic Input Screen

This produces the same types of reports as are available for the static analysis; they can be processed as discussed earlier.

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Static Output Processor

The only difference between the harmonic and static fatigue analyses is that for harmonic jobs, the calculated stresses are assumed to be zero-to-peak calculations, so they are compared to only half of the stress value extracted from the fatigue curve. Likewise, when creating the Cumulative Usage report, the number of allowable cycles is based upon twice the calculated stress. For other dynamic applications (response spectrum and time history), the stress type may be identified as fatigue by selecting the stress type from the drop list for the Load Case or Static/Dynamic Combination, and by entering the number of expected cycles in the provided field. Note that as with the harmonic analyses, the calculated stresses are assumed to be zero-to-peak calculations, so they are compared to only half of the stress value extracted from the fatigue curve. Likewise, when creating the Cumulative Usage report, the number of allowable cycles is based upon twice the calculated stress.

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Creating the .FAT Files The .FAT file is a simple text file, containing the data points necessary to describe the fatigue curve for the material, for both butt welded and fillet welded fittings. A sample FAT file is shown below. * ASME SECTION VIII DIVISION 2 FATIGUE CURVE * FIGURE 5-110.1 * DESIGN FATIGUE CURVES FOR CARBON, LOW ALLOY, SERIES 4XX, * HIGH ALLOY AND HIGH TENSILE STEELS FOR TEMPERATURES NOT * EXCEEDING 700 F * FOR UTS <= 80 KSI * 0.5000000 - STRESS MULTIPLIER (PSI); ALSO CONVERTS AMPLITUDE TO FULL RANGE * 10

580000.0

100

205000.0

1000

83000.0

10000

38000.0

100000

20000.0

500000

13500.0

1000000

12500.0

0

0.0

* This text file can be created using any available text editor. Any line beginning with an asterisk is treated as a comment line. It is highly recommended that comment lines be used so that the data can be related back to a specific material curve. The first actual data line in the file is a stress multiplier. This value is used to adjust the data values from “zero to peak” to “peak to peak” and/or to convert the stress levels to psi (the entered values will be divided by this number -- i.e., if the stress values in the file represent a stress amplitude, in psi, rather than a range, this "stress multiplier should be 0.5). Following this line is the fatigue curve data table. This table consists of eight lines, of two columns. The first column is the Cycle column, the second column is the Stress column. For each value in the cycle column, the corresponding stress value from the material fatigue curve should be listed in the stress column.

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Fatigue curves intended for use in the IGE/TD/12 code are built slightly different. The first data line contains not one, but three values: the “stress multiplier” described above, a “modulus of elasticity correction”, and a “modulus of elasticity multiplier” (the correction factor is divided by this to convert to psi) – upon file read, the “modulus of elasticity correction” is inserted into the appropriate field on the fatigue curve screen. Furthermore, the IGE/TD/12 fatigue files include five fatigue curves (sequentially Fatigue Class D, E, F, G, and W), rather than one. Optional comment lines may be used to separate the tables – these comments aid in the readability of the data file. The format of the IGE/TD/12 fatigue files can best be determined by reviewing the contents of the file TD12ST.FAT. In all tables, the number of cycles increases as you work down the table. If there is not enough data to utilize all eight lines, unused lines should be populated with zeroes.

Calculation of Fatigue Stresses For the IGE/TD/12 piping code, the computation of fatigue stresses are detailed in Section 5.4.4 of that code. This section of the code states: "The principal stress in any plane can be calculated for any set of conditions from the following formula:"

1

2×

!

( Sh + Sa ) ± ( Sh

Sa )2 + 4Sq 2

"

Where, Sh = Hoop stress Sa = Axial stress Sq = Shear stress

"This should be used for establishing the range of stress, due regard being paid to the direction and sign."

For all other piping codes in CAESAR II, the fatigue stress is computed as the stress intensity, as follows:

3D Maximum Shear Stress Intensity (Default) SI = Maximum of: S1OT - S3OT S1OB - S3OB Max(S1IT,RPS) - Min(S3IT,RPS) Max(S1IB,RPS) - Min(S3IB,RPS)

Where: S1OT=Maximum Principal Stress, Outside Top = (SLOT+HPSO)/2.0+(((SLOT-HPSO)/2.0)2+TSO2)1/2

Chapter 6 Technical Discussions

S3OT=Minimum Principal Stress, Outside Top =(SLOT+HPSO)/2.0-(((SLOT-HPSO)/2.0)2+TSO2) 1/2 S1IT=Maximum Principal Stress, Inside Top =(SLIT+HPSI)/2.0+(((SLIT-HPSI)/2.0)2+TSI2) 1/2 S3IT=Minimum Principal Stress, Inside Top =(SLIT+HPSI)/2.0-(((SLIT-HPSI)/2.0)2+TSI2) 1/2 S1OB=Maximum Principal Stress, Outside Top =(SLOB+HPSO)/2.0+ (((SLOB-HPSO)/2.0)2+TSO2) 1/2 S3OB=Minimum Principal Stress, Outside Bottom =(SLOB+HPSO)/2.0- (((SLOB-HPSO)/2.0)2+TSO2) 1/2 S1IB=Maximum Principal Stress, Inside Bottom =(SLIB+HPSI)/2.0+ (((SLIB-HPSI)/2.0)2+TSI2) 1/2 S3IB=Minimum Principal Stress, Inside Bottom =(SLIB+HPSI)/2.0- (((SLIB-HPSI)/2.0)2+TSI2) 1/2 RPS=Radial Pressure Stress, Inside HPSI=Hoop Pressure Stress (Inside, from Lame's Equation) HPSO=Hoop Pressure Stress (Outside, from Lame's Equation) SLOT=Longitudinal Stress, Outside Top SLIT=Longitudinal Stress, Inside Top SLOB=Longitudinal Stress, Outside Bottom SLIB=Longitudinal Stress, Inside Bottom TSI=Torsional Stress, Inside TSO=Torsional Stress, Outside

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Pipe Stress Analysis of FRP Piping Underlying Theory The behavior of steel and other homogeneous materials has been long understood, permitting their widespread use as construction materials. The development of the piping and pressure vessel codes (Reference 1) in the early part of this century led to the confidence in their use in piping applications; the work of Markl et. al. in the 1940’s and 1950’s was responsible for the formalization of today’s pipe stress methods, leading to an ensuing diversification of piping codes on an industry by industry basis. The advent of the digital computer, and with it the appearance of the first pipe stress analysis software (Reference 2), further increased the confidence with which steel pipe could be used in critical applications. The 1980’s saw the wide spread proliferation of the micro computer, with associated pipe stress analysis software, which in conjunction with training, technical support, and available literature, has brought stress analysis capability to almost all engineers. In short, an accumulated experience of close to 100 years, in conjunction with ever improving technology has led to the utmost confidence on the part of today’s engineers when specifying, designing, and analyzing steel, or other metallic, pipe. For fiberglass reinforced plastic (FRP) and other composite piping materials, the situation is not the same. Fiberglass reinforced plastic was developed only as recently as the 1950’s, and did not come into wide spread use until a decade later (Reference 3). There is not a large base of stress analysis experience, although not from a lack of commitment on the part of FRP vendors. Most vendors conduct extensive stress testing on their components, including hydrostatic and cyclic pressure, uniaxial tensile and compressive, bending, and combined loading tests. The problem is due to the traditional difficulty associated with, and lack of understanding of, stress analysis of heterogeneous materials. First, the behavior and failure modes of these materials are highly complex and not fully understood, leading to inexact analytical methods, and a general lack of agreement on the best course of action to follow. This lack of agreement has slowed the simplification and standardization of the analytical methods into universally recognized codes (BS 7159 Code (Design and Construction of Glass Reinforced Plastics Piping Systems for Individual Plants or Sites) and UKOOA Specification and Recommended Practice for the Use of GRP Piping Offshore being notable exceptions). Secondly, the heterogeneous, orthotropic behavior of FRP and other composite materials has hindered the use of the pipe stress analysis algorithms developed for homogeneous, isotropic materials associated with crystalline structures. A lack of generally accepted analytical procedures has contributed to a general reluctance to use FRP piping for critical applications. Stress analysis of FRP components must be viewed on many levels. These levels, or scales, have been called “Micro-Mini-Macro” levels, with analysis proceeding along the levels according to the “MMM” principle (Reference 4).

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Micro-Level Analysis Stress analysis on the “Micro” level refers to the detailed evaluation of the individual materials and boundary mechanisms comprising the composite material. In general, FRP pipe is manufactured from laminates, which are constructed from elongated fibers of a commercial grade of glass (called E-glass), which are coated with a coupling agent or sizing prior to being embedded in a thermosetting plastic material, typically epoxy or polyester resin. This means, on the micro scale, that an analytical model must be created which simulates the interface between these elements. Since the number and orientation of fibers is unknown at any given location in the FRP sample, the simplest representation of the micro-model is that of a single fiber, extending the length of the sample, embedded in a square profile of matrix. Evaluation of this model requires use of the material parameters of 1

the glass fiber

2

the coupling agent or sizing layer (normally of such microscopic proportion that it may be ignored)

3

the plastic matrix

It must be considered that these material parameters may vary for an individual material based upon tensile, compressive, or shear applications of the imposed stresses, and typical values vary significantly between the fiber and matrix (Reference 5): Young's Modulus

Ultimate Strength

Coefficient of Thermal Expansion

Material

tensile (MPa)

tensile (MPa)

m/m/°C

Glass Fiber

7.25 x 103

1.5 x 103

5.0 x 10-6

Plastic Matrix

2.75 x 103

7.0 x 101

7.0 x 10-3

The following failure modes of the composite must be similarly evaluated: failure of the fiber failure of the coupling agent layer failure of the matrix failure of the fiber-coupling agent bond failure of the coupling agent-matrix bond Because of uncertainties about the degree to which the fiber has been coated with the coupling agent and about the nature of some of these failure modes, this evaluation is typically reduced to failure of the fiber failure of the matrix failure of the fiber-matrix interface

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Micro-Level GRP Sample-- Single Fiber Embedded in Square Profile of Matrix

Stresses in the individual components can be evaluated through finite element analysis of the strain continuity and equilibrium equations, based upon the assumption that there is a good bond between the fiber and matrix, resulting in compatible strains between the two. For normal stresses applied parallel to the glass fiber: (f = (m = af

=

am

af

/ Ef =

am

/ Em

Ef / Em

Where: (f

=

strain in the fiber

(

=

strain in the matrix

=

normal stress parallel to fiber, in the fiber

af

Ef = am

E

modulus of elasticity of the fiber

=

axial normal stress parallel to fiber, in the matrix

=

modulus of elasticity of the matrix

Due to the large ratio of the modulus of elasticity of the fiber to that of the matrix, it is apparent that nearly all of the axial normal stress in the fiber-matrix composite is carried by the fiber. Exact values are (Reference 6): af

=

L

/ [ + (1- )Em/Ef]

am

=

L

/ [ Em/Ef + (1- )]

Where: L

= nominal longitudinal stress across composite

= glass content by volume

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The continuity equations for the glass-matrix composite seem less complex for normal stresses perpendicular to the fibers, since the weak point of the material seems to be limited by the glass-free cross-section shown in the following figure. For this reason, it would appear that the strength of the composite would be equal to that of the matrix for stresses in this direction; in fact, its strength is less than that of the matrix due to stress intensification in the matrix caused by the irregular stress distribution in the vicinity of the stiffer glass. (Since the elongation over distance D1 must be equal to that over the longer distance D2, the strain, and thus the stress at location D1 must exceed that at D2 by the ratio D2/D1.) Maximum intensified transverse normal stresses in the composite are:

=

*

!

(1

)1.25 +

( Em E f ) /(1 Vm2 )

2

(1 + 0.85 )[1 + (2 + 3

"

)1 ( Em E f )(1 Vm2 )]

Where: b

= intensified normal stress transfer to the fiber, in the composite

^

= nominal transverse normal stress across composite

V = Poisson’s ratio of the matrix

Note:

Because of the Poisson effect, this stress produces an additional s'’am equal to the following: am

= Vm

Shear stress can be allocated to the individual components again through the use of continuity equations; it would appear that the stiffer glass would resist the bulk of the shear stresses; however, unless the fibers are infinitely long, all shears must eventually pass through the matrix in order to get from fiber to fiber. Shear stress between fiber and matrix can be estimated as qo =

T(1-p)1.25 +p(G m /G f ) (1+0.6rp 2 )1-r( 2rp3 n)1-(G m /G f )

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Where: ,ab = intensified shear stress in composite T

= nominal shear stress across composite

Gm = shear modulus of elasticity in matrix Gf = shear modulus of elasticity in fiber Determination of the stresses in the fiber-matrix interface is more complex. The bonding agent has an inappreciable thickness, and thus has an indeterminate stiffness for consideration in the continuity equations. Also, the interface behaves significantly differently in shear, tension, and compression, showing virtually no effects from the latter. The state of the stress in the interface is best solved by omitting its contribution from the continuity equations, and simply considering that it carries all stresses which must be transferred from fiber to matrix. Once the stresses have been apportioned, they must be evaluated against appropriate failure criteria. The behavior of homogeneous, isotropic materials such as glass and plastic resin, under a state of multiple stress is better understood. A failure criterion for isotropic material reduces the combined normal and shear stresses (sa, sb, sc, tab, tac, tbc) to a single stress, an “equivalent stress,” which can be compared to the tensile stress present at failure in a material under uniaxial loading, i.e. the ultimate tensile stress, Sult. Different theories, and different equivalent stress functions f(sa, sb, sc, tab, tac, tbc) have been proposed, with possibly the most widely accepted being the Huber-von Mises-Hencky criterion, which states that failure will occur when the equivalent stress reaches a critical value – the ultimate strength of the material: eq

=

-{1/2 [(

a

-

)2 + (

b

a

-

)2 + (

c

b

-

)2] + 6(,ab2 + ,ac2+ ,bc2)}

c

Sult

This theory does not fully cover all failure modes of the fiber, in that it omits reference to direction of stress (i.e., tensile vs. Compressive). The fibers, being relatively long and thin, predominantly demonstrate buckling as their failure mode when loaded in compression. The equivalent stress failure criterion has been corroborated (with slightly non-conservative results) by testing. Little is known about the failure mode of the adhesive interface, although empirical evidence points to a failure criterion which is more of a linear relationship between the normal and the square of the shear stresses. Failure testing of a composite material loaded only in transverse normal and shear stresses are shown in the following figure; the kink in the curve shows the transition from the matrix to the interface as the failure point.

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75

Mini-Level Analysis

Although feasible in concept, micro level analysis is not feasible in practice. This is due to the uncertainty of the arrangement of the glass in the composite—the thousands of fibers which may be randomly distributed, semi-randomly oriented (although primarily in a parallel pattern), and of randomly varying lengths. This condition indicates that a sample can truly be evaluated only on a statistical basis, thus rendering detailed finite element analysis inappropriate. For mini-level analysis, a laminate layer is considered to act as a continuous (hence the common reference to this method as the “continuum” method) material, with material properties and failure modes estimated by integrating them over the assumed cross-sectional distribution, i.e., averaging. The assumption regarding the distribution of the fibers can have a marked effect on the determination of the material parameters; two of the most commonly postulated distributions are the square and the hexagonal, with the latter generally considered to be a better representation of randomly distributed fibers. The stress-strain relationships, for those sections evaluated as continua, can be written as: (aa =

aa

/EL - (V L/EL)

bb

- (V L/EL)

cc

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(bb = -( VL/EL)

aa

+

(cc = -( VL/EL)

aa

- (VT/ET)

/ET - (VT/ET)

bb

bb

+

cc

/ET

cc

(ab = ,ab / 2 GL (bc = ,bc / 2 GT (ac = ,ac / 2 GL Where: (ij = strain along direction i on face j , ,ab = stress (normal, shear) along direction i on face j

ij

EL = modulus of elasticity of laminate layer in longitudinal direction VL = Poisson’s ratio of laminate layer in longitudinal direction ET = modulus of elasticity of laminate layer in transverse direction VT = Poisson’s ratio of laminate layer in transverse direction GL = shear modulus of elasticity of laminate layer in longitudinal direction GT = shear modulus of elasticity of laminate layer in transverse direction These relationships require that four moduli of elasticity (EL, ET, GL, and GT) and two Poisson’s ratios (VL and VT) to be evaluated for the continuum. Extensive research (References 4 - 10) has been done to estimate these parameters. There is general consensus that the longitudinal terms can be explicitly calculated; for cases where the fibers are significantly stiffer than the matrix, they are: EL = EF + EM(1 - ) GL = GM + / [ 1 / (GF - GM) + (1 - ) / (2GM)] VL = VF + VM(1 - ) Parameters in the transverse direction cannot be calculated; only their upper and lower bounds can. Correlation with empirical results have yielded approximations (Reference 5 and 6): GT = GM (1 + 0.6- ) / [(1 - )1.25 +

(GM/GF)]

VT = VL (EL / ET) Use of these parameters permits the development of the homogeneous material models which facilitate the calculation of longitudinal and transverse stresses acting on a laminate layer. The resulting stresses may be allocated to the individual fibers and matrix using relationships developed during the micro analysis.

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77

Macro-Level Analysis

Where Mini-level analysis provides the means of evaluation of individual laminate layers, Macro-level analysis provides the means of evaluating components made up of multiple laminate layers. It is based upon the assumption that not only the composite behaves as a continuum, but that the series of laminate layers acts as a homogeneous material with properties estimated based on the properties of the layer and the winding angle, and that finally, failure criteria are functions of the level of equivalent stress. Laminate properties may be estimated by summing the layer properties (adjusted for winding angle) over all layers. For example ELAM||

=

(1 / tLAM)(E||k Cik + E^k Cjk) tk

Where: ELAM||

=

tLAM =

thickness of laminate

E^k =

Longitudinal modulus of elasticity of laminate layer k

Cik =

transformation matrix orienting axes of layer k to longitudinal laminate axis

Cjk =

transformation matrix orienting axes of layer k to transverse laminate axis

=

tk

Longitudinal modulus of elasticity of laminate

thickness of laminate layer k

Once composite properties are determined, the component stiffness parameters may be determined as though it were made of homogeneous material – i.e., based on component cross-sectional and composite material properties. Normal and shear stresses can be determined from 1) forces and moments acting on the cross-sections, and 2) the cross-sectional properties themselves. These relationships can be written as aa

=

Faa / Aaa ± Mba / Sba ± Mca / Sca

bb

=

Fbb / Abb ± Mab / Sab ± Mcb / Scb

cc

=

Fcc / Acc ± Mac / Sac ± Mbc / Sbc

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,ab =

Fab / Aab ± Mbb / Rab

,ac =

Fac / Aac ± Mcc / Rac

,ba =

Fba / Aba ± Maa / Rba

,bc =

Fbc / Abc ± Mcc / Rbc

,ca =

Fca / Aca ± Maa / Rca

,cb =

Fcb / Acb ± Mbb / Rcb

Where: ij

=

normal stress along axis i on face j

Fij =

force acting along axis i on face j

Aij =

area resisting force along axis i on face j

Mij =

moment acting about axis i on face j

Sij =

section modulus about axis i on face j

,ij =

shear stress along axis i on face j

Rij =

torsional resistivity about axis i on face j

Using the relationships developed under macro, mini, and micro analysis, these stresses can be resolved back into local stresses within the laminate layer, and from there, back into stresses within the fiber and the matrix. From these, the failure criteria of those microscopic components, and hence, the component as a whole, may be checked.

Implementation of Macro-Level Analysis for Piping Systems The macro-level of analysis described above is the basis for the preeminent FRP piping codes in use today, including the BS 7159 Code (Design and Construction of Glass Reinforced Plastics Piping Systems for Individual Plants or Sites) and the UKOOA Specification and Recommended Practice for the Use of GRP Piping Offshore. BS 7159 uses methods and formulas familiar to the world of steel piping stress analysis in order to calculate stresses on the cross-section, with the assumption that FRP components have material parameters based on continuum evaluation or test. All coincident loads, such as thermal, weight, pressure, and axial extension due to pressure need be evaluated simultaneously. Failure is based on the equivalent stress calculation method; since one normal stress (radial stress) is traditionally considered to be negligible in typical piping configurations, this calculation reduces to the greater of (except when axial stresses are compressive): 2

S eq

=

Sx + 4t

S eq

=

Sh + 4t

2

2

(when axial stress is greater than hoop) 2

(when hoop stress is greater than axial)

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79

A slight difficulty arises when evaluating the calculated stress against an allowable, due to the orthotropic nature of the FRP piping – normally the laminate is designed in such a way to make the pipe much stronger in the hoop, than in the longitudinal, direction, providing more than one allowable stress. This is resolved by defining the allowable in terms of a design strain ed, rather than stress, in effect adjusting the stress allowable in proportion to the strength in each direction – i.e., the allowable stresses for the two equivalent stresses above would be (ed ELAMX) and (ed ELAMH) respectively. In lieu of test data, system design strain is selected from Tables 4.3 and 4.4 of the Code, based on expected chemical and temperature conditions. Actual stress equations as enumerated by the BS 7159 Code are shown below: 1

Combined stress: straights and bends: C

=(

2 f

+4

=(

2 X

)

2 0.5 S

(d ELAM

or C

+4

)

2 0.5 S

(d ELAM

Where: = combined stress

C

= circumferential stress =

P

+

B

=torsional stress

S

= MS(Di + 2td) / 4I = longitudinal stress

X

= P

XP

+

XB

= circumferential pressure stress = mP(Di + td) / 2 td

B

= circumferential bending stress = [(Di + 2td) / 2I] [(Mi SIF i)2 + Mo SIF o)2] 0.5 (for bends, = 0 for straights)

MS = torsional moment on cross-section D = internal pipe diameter td

= design thickness of reference laminate

I

= moment of inertia of pipe

m = pressure stress multiplier of component P

= internal pressure

Mi = in-plane bending moment on cross-section SIF i = circumferential stress intensification factor for in-plane moment M = out-plane bending moment on cross-section SIF = circumferential stress intensification factor for out-plane moment XP

= longitudinal pressure stress = P(Di + td) / 4 td

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CAESAR II Technical Reference Manual

XB

= longitudinal bending stress = [(Di + 2td) / 2I] [(Mi SIFxi)2 + Mo SIFxo)2]0.5

SIF = longitudinal stress intensification factor for in-plane moment SIF = longitudinal stress intensification factor for out-plane moment 2

Combined stress: branch connections: CB

= ((

P

+

)2 + 4

bB

) £ ed ELAM

2 0.5 SB

Where: CB

P

= branch combined stress = circumferential pressure stress = mP(Di + tM) / 2 tM

bB

= non-directional bending stress = [(Di + 2td) / 2I] [(Mi SIFBi)2 + Mo SIFBo)2]0.5

SB

= branch torsional stress = MS(Di + 2td) / 4I

tM = thickness of the reference laminate at the main run SIFBi = branch stress intensification factor for in-plane moment SIFB = branch stress intensification factor for out-plane moment 3

When longitudinal stress is negative (net compressive): - Vfx

x

( ELAM

Where: Vfx = Poisson’s ratio giving strain in longitudinal direction caused by stress in circumferential direction (

= design strain in circumferential direction

ELAM = modulus of elasticity in circumferential direction

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81

The BS 7159 Code also dictates the means of calculating flexibility and stress intensification (k- and i-) factors for bend and tee components, for use during the flexibility analysis.

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CAESAR II Technical Reference Manual

BS 7159 SIF Factors for Bends

The BS 7159 Code imposes a number of limitations on its use, the most notable being the limitation of a system to a design pressure of 10 bar, the restriction to the use of designated design laminates, and the limited applicability of the k- and i- factor calculations to pipe bends (i.e, mean wall thickness around the intrados must be 1.75 times the nominal thickness or less).

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83

BS 7159 SIF Factors for Tees

This code appears to be more sophisticated, yet easy to use, than any available alternative, so it is recommended here that its calculation techniques be applied even to FRP systems outside its explicit scope, with the following recommendations: Pressure stiffening of bends should be based on actual design pressure, rather than allowable design strain. Design strain should be based on manufacturer’s test and experience data wherever possible (with consideration for expected operating conditions). Fitting k- and i- factors should be based on manufacturer’s test or analytic data if available. The UKOOA Specification is similar in many respects to the BS 7159 Code, except that it simplifies the calculational requirements in exchange for imposing more limitations and more conservatism on the piping operating conditions. Rather than explicitly calculating a combined stress, the specification defines an idealized envelope of combinations of axial and hoop stresses which cause the equivalent stress to reach failure. This curve represents the plot of: ( x/

x-all

)2 + (

hoop

/

hoop-all

)2 - [

x

hoop

/(

x-all

hoop-all

)]

1.0

Where: x-all

= allowable stress, axial

hoop-all

= allowable stress, hoop

The Specification conservatively limits the user to that part of the curve falling under the line between x-all (also known as sa(0:1)) and the intersection point on the curve where hoop is twice sx-(a natural condition for a pipe loaded only with pressure), as shown in the following figure.

CAESAR II UKOOA Envelope Graphics

An implicit modification to this requirement is the fact that pressure stresses are given a factor of safety (typically equal to 2/3) while other loads are not. This gives an explicit requirement of Pdes

f1 f2 f3 LTHP

Where: Pdes = allowable design pressure

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f1 = factor of safety for 97.5% lower confidence limit, usually 0.85 f2 = system factor of safety, usually 0.67 f3 = ratio of residual allowable, after mechanical loads = 1 - (2 a

b

a

) / (r f1 LTHS)

b

= axial bending stress due to mechanical loads

r=

aa(0:1)

a(0:1)

a(2:1)

b

/

a(2:1)

= long term axial tensile strength in absence of pressure load

= long term axial tensile strength under only pressure loading

LTHS = long term hydrostatic strength (hoop stress allowable) LTHP = long term hydrostatic pressure allowable Note:

This has been implemented in the CAESAR II pipe stress analysis software as:

Code Stress a

b

(f2 /r) + PDm / (4t)

Code Allowable (f1 f2 LTHS) / 2.0

Where: P = design pressure D = pipe mean diameter t = pipe wall thickness and i-factors for bends are to be taken from the BS 7159 Code, while no such factors are to be used for tees. The UKOOA Specification is limited in that shear stresses are ignored in the evaluation process; no consideration is given to conditions where axial stresses are compressive; and most required calculations are not explicitly detailed.

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85

FRP Analysis Using CAESAR II Practical Applications CAESAR II has had the ability to model orthotropic materials such as FRP almost since its inception. It also can specifically handle the requirements of the BS 7159 Code and the UKOOA Specification. FRP material parameters corresponding to those of many vendors’ lines are provided with CAESAR II and may be pre-selected by the user to be the default values whenever FRP piping is used. Other options, as to whether the BS 7159 pressure stiffening requirements should be carried out using design strain or actual strain can be set in CAESAR II’s configuration module as well.

The FRP Properties Table of the Configuration Setup Dialog

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CAESAR II Technical Reference Manual

Special Execution Parameters for Activating the Orthotropic Material Model

Selecting material 20 — Plastic (FRP) – activates CAESAR II’s orthotropic material model and brings in the appropriate material parameters from the pre-selected materials. The orthotropic material model is indicated by the changing of two fields from their previous isotropic values: “Elastic Modulus (C)” —> “Elastic Modulus/axial” and “Poisson's Ratio” —> “Ea/Eh*Vh/a”. These changes are necessary due to the fact that orthotropic models require more material parameters than do isotropic. For example, there is no longer a single modulus of elasticity for the material, but now two — axial and hoop. There is no longer a single Poisson’s ratio, but again two — Vh/a (Poisson’s ratio relating strain in the axial direction due to stress-induced strain in the hoop direction) and Va/h (Poisson’s ratio relating strain in the hoop direction due to stress-induced strain in the axial direction). Also, unlike isotropic materials, the shear modulus does not follow the relationship G = 1 / E (1-V), so that value must be explicitly input as well.

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87

Example of Orthotropic Parameters Required in Piping Input

In order to minimize input, a few of these parameters can be combined, due to their use in the program. Generally, the only time that the modulus of elasticity in the hoop direction, or the Poisson’s ratios are used during flexibility analysis is when calculating piping elongation due to pressure (note that the modulus of elasticity in the hoop direction is used when determining certain stress allowables for the BS 7159 code): dx = (

x

/ Ea - Vh/a *

hoop

/ Eh ) L

Where: dx = extension of piping element due to pressure x

= longitudinal pressure stress in the piping element

Ea = modulus of elasticity in the axial direction Vh/a = Poisson’s ratio relating strain in the axial direction due to stress-induced strain in the hoop direction hoop

= hoop pressure stress in the piping element

Eh = modulus of elasticity in the hoop direction L = length of piping element

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CAESAR II Technical Reference Manual

This equation can be rearranged, to require only a single new parameter, as dx = ( Note:

x

-

hoop

* (Ea / Eh * Vh/a)) * L / Ea

In theory, that single parameter, (Ea / Eh * Vh/a) is identical to Va/h.

The shear modulus of the material is required in ordered to develop the stiffness matrix; in CAESAR II, this value, expressed as a ratio of the axial modulus of elasticity, is brought in from the pre-selected material, or can be changed on a problem-wise basis using the special execution parameter screen accessed by the Kaux “menu” from the piping spreadsheet (see figure). This screen also shows the coefficient of thermal expansion (extracted from the vendor file or entered by the user) for the material, as well as the default laminate type, as defined by the BS 7159 Code: Type 1 – All chopped strand mat (CSM) construction with an internal and an external surface tissue reinforced layer. Type 2 – Chopped strand mat (CSM) and woven roving (WR) construction with an internal and an external surface tissue reinforced layer. Type 3 – Chopped strand mat (CSM) and multi-filament roving construction with an internal and an external surface tissue reinforced layer. The latter is used during the calculation of flexibility and stress intensification factors for piping bends. Bend and tee information may be entered easily through use of auxiliary spreadsheets. Bend radius and laminate type may be changed on a bend by bend basis, as shown in the corresponding figure. BS 7159 fabricated and moulded tee types are specified by defining CAESAR II tee types 1 and 3 respectively at intersection points. CAESAR II automatically calculates the appropriate flexibility and stress intensification factors for these fittings as per code requirements.

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89

Required code data may be entered on the ALLOWABLES auxiliary spreadsheet; with the program providing fields for CODE (both number 27 – BS 7159 and 28 – UKOOA are available). After selection of BS 7159, CAESAR II provides fields for entry of the following code parameters: SH1,2,3 = longitudinal design stress = (d ELAMX Kn1,2,3 = cyclic reduction factor (as per BS 7159 paragraph 4.3.4) Eh/Ea = ratio of hoop modulus of elasticity to axial modulus of elasticity K = temperature differential multiplier (as per BS 7159 paragraph 7.2.1)

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CAESAR II Technical Reference Manual

After selection of UKOOA, CAESAR II provides fields for entry of the following code parameters: SH1,2,3 = hoop design stress = f1 * LTHS R1,2,3 = ratio r (

a(0:1)

/

a(2:1)

)

f1 = system factor of safety (defaults to 0.67 if omitted) K = temperature differential multiplier (same as BS 7159) These parameters need only be entered a single time, unless they change at some point in the system.

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91

Performing the analysis is even simpler than the system modeling. CAESAR II evaluates the operating parameters and automatically builds the appropriate load cases; in this case three are built: Operating (includes pipe and fluid weight, temperature, equipment displacements, pressure, etc.). This case is used to determine maximum code stress/strain, operational equipment nozzle and restraint loads, hot displacements, etc. Cold (same as above, except excluding temperature and equipment movements). This case is used to determine cold equipment nozzle and restraint loads. Expansion (cyclic stress range between the cold and hot case). This case may be used to evaluate fatigue criteria as per paragraph 4.3.4 of the BS 7159 Code. After analyzing the response of the system under these loads, CAESAR II presents the user with a menu of possible output reports. Reports may be designated by selecting a combination of load case and results type (displacements, restraint loads, element forces and moments, and stresses). From the stress report, the user can determine at a glance whether the system passed or failed the stress criteria. For UKOOA code, the piping is considered to be within allowables when the operating stress falls within the idealized stress envelope (indicated by the straight line in the following figure).

Conclusion A reliable, powerful, yet easy to use, pipe stress analysis program with world wide acceptance is now available for evaluation of FRP piping systems as per the requirements of the most sophisticated FRP piping codes. This means that access to the same analytical methods and tools long enjoyed by engineers using steel pipe is available to any potential user of FRP piping – ensuring that design.

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References 1

Cross, Wilbur, An Authorized History of the ASME Boiler an Pressure Vessel Code, ASME, 1990

2

Olson, J. and Cramer, R., “Pipe Flexibility Analysis Using IBM 705 Computer Program MEC 21, Mare Island Report 277-59,” 1959

3

Fiberglass Pipe Handbook, Composites Institute of the Society of the Plastics Industry, 1989

4

Hashin, Z., “Analysis of Composite Materials – a Survey,” Journal of Applied Mechanics, Sept. 1983

5

Greaves, G., “Fiberglass Reinforced Plastic Pipe Design,” Ciba-Geigy Pipe Systems

6

Puck, A. and Schneider, W., “On Failure Mechanisms and Failure Criteria of Filament-Wound GlassFibre/Resin Composites,” Plastics and Polymers, Feb. 1969

7

Hashin, Z., “The Elastic Moduli of Heterogeneous Materials,” Journal of Applied Mechanics, March 1962

8

Hashin, Z. and Rosen, B. Walter, “The Elastic Moduli of Fibre Reinforced Materials,” Journal of Applied Mechanics, June 1964

9

Whitney, J. M. and Riley, M. B., “Elastic Properties of Fiber Reinforced Composite Materials,” AIAA Journal, Sept. 1966

10 Walpole, L. J., “Elastic Behavior of Composite Materials: Theoretical Foundations,” Advances in Applied Mechanics, Volume 21, Academic Press, 1989 11 BS 7159: 1989 – British Standard Code of Practice for Design and Construction of Glass Reinforced Plastics (GRP) Piping Systems for Individual Plants or Sites 12 UK Offshore Operators Association Specification and Recommended Practice for the Use of GRP Piping Offshore — 1994

Chapter 6 Technical Discussions

93

Code Compliance Considerations General Notes for All Codes This section comprises general notes that cover code compliance. The first several pages contain information that applies to all of the codes. The last pages contain code-specific discussions. The user is urged to review the general notes once, highlighting those that apply to his specific type of problem. He is also recommended to review the notes for the particular piping code to be used. Chapter 2 (see "Configuration and Environment" on page 1) of the Technical Reference Manual gives details about the various parameters that can be used in the CAESAR II setup file. Many of these parameters are discussed from an “application point-of-view” in the text that follows. Users not familiar with the setup file should see Chapter 2 (see "Configuration and Environment" on page 1) of the Technical Reference Manual. An SIF of 2.3 is used for threaded joints for all codes. An SIF of 1.2 is used for double welded slip-on flanges for all codes. An SIF of 1.6 is used for lap joint flanges with B16.9 stub ends for all codes. The only piping codes that cannot take advantage of the WRC 329 options, or the option to use the ASME NC and ND rules for reduced intersections, are BS806 and the Swedish Power Method 1. These codes have no provision for using the effective section modulus, and any extrapolation of the ASME methods into these codes at this time is considered unwarranted. The Weld ID on the SIF & TEE Auxiliary field is used in the calculation of the Bonney Forge Sweepolet and Bonney Forge Insert Weldolet. If the user can be sure that the welds for these fittings will be finished or dressed, then the specification of the Weld ID will result in lower stress intensification factors. Bend SIF overrides by the user effect the entire cross section of the bend, and as such cannot be specified for only a single point on the bend curvature. The user’s defined SIF should be specified for the bend “TO” node. CAESAR II will then apply this SIF, (in place of the code’s SIF) over the entire bend curvature, i.e. from weldline to weldline. The default fiberglass-reinforced plastic (FRP) bend and intersection SIF is 2.3. This value is used for all bends and for all intersections unless otherwise modified by the user. Flexibility factors for FRP bends are 1.0. Users modifying these values are cautioned that SIFs generated from steel fatigue tests may not be applicable as a basis for SIFs for FRP fittings. At this time stress intensification factors cannot be less than 1.0. Because original SIF work used girth butt welds as a basis, some manufacturers are generating SIFs for their fittings that are less than 1.0 implying that the fitting is stronger than a girth butt weld. CAESAR II does not permit the use of these reduced SIFs at this time. The REDUCED_INTERSECTION calculations discussed at length in the following text apply whenever d/D < 0.975. Where (d) is the outside diameter of the branch, and (D) is the outside diameter of the header. WRC 329/330 for the codes: B31.3, B31.4, B31.11, and B31.1 (1967) does the following: 1

Include torsional stresses in all stress calculations, (i.e. Sustained and Occasional)

2

Use a torsional SIF of (r/R) io.

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CAESAR II Technical Reference Manual

3

Compute i(ib) from: 0.6(R/T)**2/3 [1+0.5(r/R)**3](r/rp)

4

For i(ob) use 1.5(R/T)**2/3 (r/R)**1/2 (r/rp), and i(ob)(t/T)>1.5

when (r/R) < 0.9., use 0.9(R/T)**2/3 (r/rp), and i(ob)(t/T)>1.0 when (r/R) = 1.0, and use interpolation when 1.0 > (r/R) > 0.9 5

For ir use 0.8 (R/T)**2/3 (r/R), and ir > 2.1

6

If a radius at the junction is provided greater than the larger of t/2 or T/2, then the calculated SIFs may be divided by 2.0, but with ib>1.5 and ir>1.5.

WRC 329/330 for the codes: B31.1, B31.8, ASME III NC & ND, Navy 505, Z183, Z184, and Swedish Method 2, do the following: 1

For ib, use 1.5(R/T)**2/3 (r/R)**1/2 (r/rp), and ib(t/T)>1.5 when (r/R) < 0.9. use 0.9(R/T)**2/3 (r/rp), and ib(t/T)>1.0 when (r/R) = 1.0, and use interpolation when 1.0 > (r/R) > 0.9

2

For ir, use 0.8 (R/T)**2/3 (r/R), and ir > 2.1

3

If a radius at the junction is provided greater than the larger of t/2 or T/2, then the calculated SIFs may be divided by 2.0, but with ib>1.5 and ir>1.5.

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Bonney Forge Sweepolets tend to be a little more conservative because they are used for fittings in the Nuclear industry. The Bonney Forge Sweepolet equations can generate SIFs less than one because they are stronger than the girth butt weld used as the unity basis for the code fitting SIFs. CAESAR II does not permit SIFs of less than 1.0. If a Bonney Forge Sweepolet SIF is generated that is less than 1.0, 1.0 will be used. Even though CAESAR II allows the specification of two element intersections, the user cannot specify two SIFs at a single node and get an increased SIF. For example a socketweld SIF and an intersection SIF cannot be specified at the same point. For two element joints the largest diameter and the smallest T is used when discrepancies exist between the two adjoining pipes. When the two element fitting is a socket weld then the largest T is used. These selections are made to generate the largest SIFs and thus the most conservative stress calculations for under specified fittings. Note: The mismatch given for girth butt welds is the average mismatch and not the maximum mismatch. Users must make sure that any maximum mismatch requirements are satisfied themselves. If a fillet leg is given in conjunction with a socket weld SIF definition, then both socket weld types result in the same SIF. The B31.3 sustained case SIF factor in the setup file affects all of the following codes: B31.4, B31.8, B31.11, Navy 505, Z662, and B31.1 (1967). The default for the B31.3_SUS_CASE_SIF_FACTOR=1.0. The calculation for the corroded effective section modulus is made from (pi)(r2)te where (r) is the average cross sectional radius of the non-corroded pipe and (te) is the corroded thickness. The thickness (te) is selected based on the noncorroded thicknesses of the branch and header, i.e. the lesser of Th and iTb. The resulting value has the corrosion subtracted from it before the effective section modulus calculation is made. The Maximum Shear Stress is always calculated with the corroded wall thickness, regardless of the setting of the ALL_STRESS_CASES_CORRODED flag in the setup file. If different piping codes are used in one job. The code reported at the top of the output stress report will be the code that was last encountered during model input. SIFs, allowables and code equations are all computed in accordance with the code that is varying with the input. The following piping codes do not, by default, include torsion in the sustained or occasional stress calculations: B31.3

Navy 505

B31.4

Z662

B31.8

B31.1 (1967)

B31.11

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Torsion is not added because these codes instruct the user to add the “longitudinal stresses” due to weight, pressure and other sustained loadings. Torsional shear stresses are not longitudinal stresses. The user can request that torsion be added into the sustained and occasional stress equations by putting the parameter: ADD_TORSION_IN_SL_STRESS=YES in the setup file. The torsion stress is still however not intensified, as it is in the power piping codes. This lack of intensification is considered an oversight, and is corrected in WRC 329. The user can implement this fix in his running of any of the above codes by putting the parameter: USE_WRC330 in the setup file. Note that the radius given in CAESAR II is always the equivalent “closely spaced miter” radius. The radius calculation given for widely spaced miters in the piping codes is only to be used when the user breaks the widely spaced miter bend down into individual single cut miters as recommended. B31.1 and the ASME Section III piping codes provide stress intensification factors for reduced branch ends. None of the other piping codes provide these SIFs. The REDUCED INTERSECTION= parameter in the setup file allows the user of other piping codes to access these improved SIFs for reduced fittings. Users taking advantage of this option should review the notes associated with the B31.1 and the ASME Section III codes that follow to make sure that any other parameters or input associated with the reduced intersection calculations are set as necessary. When the user requests pressure stiffening for those codes that do not normally provide it, the pressure stiffening is applied for all bends and for both miter types. The defaults for the occasional load factor from the setup file used in the evaluation of the allowable stress, is given in the text that follows for each of the piping codes. B31.1: The occasional load factor is 1.15. B31.3: The occasional load factor is 1.33. B31.4: This is 0.8Sy as defined in the most recent edition of B31.4. OCC does not effect a B31.4 analysis in CAESAR II. B31.5: The occasional load factor is 1.33. B31.8: An occasional case is not specifically defined. If the user enters an OCC load case the allowable will default to 1.0 times the sustained allowable stress, i.e. OCC=1.0 B31.11: This is 0.88Sy as defined in the most recent edition of B31.11 OCC does not effect a B31.11 analysis in CAESAR II. ASME Section III NC and ND: The default value of OCC is 1.2 so, the occasional stress allowable is 1.8 (1.2 X 1.5) Sh but not greater than 1.5 Sy. If OCC is set to 1.5 or 2.0, the allowable is set to the minimum of 2.25 Sh/1.8 Sy (Level C) or 3.0 Sh/2.0Sy (Level D). Note in the latter two cases, Sm should be entered for Sh. Navy 505: Occasional cases are not addressed but will default to the method used in B31.1, and an OCC value of 1.15 will be used as the default. Z662: Occasional cases not defined, but if entered by the user the allowable for the case will default to 1.0 times the sustained allowable. BS806: The occasional load case is not defined. If entered the allowable stress for the OCC load case will be K Sh, (the occasional load factor times the sustained allowable). The default for “k” is 1.0. Swedish Method 1: OCC is not used. The load cases are not differentiated. The same allowable Sigma(ber)/1.5 is used for all load cases. Swedish Method 2: An OCC default of 1.2 as recommended in the Swedish Piping Code is used. B31.1(1967): OCC default is 1.15. Stoomwezen: OCC default is 1.2. RCC-M C&D: OCC default is 1.2.

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CODETI: OCC default is 1.15. NORWEGIAN: OCC default is 1.2. FBDR: OCC default is 1.15 BS 7159: The occasional load case is not defined. UKOOA: The occasional load case is not defined. IGE/TD/12: Occasional stress increases are addressed is Table 4 of the code. The occasional factor in the setup file has no bearing on this code. The occasional load factor can be changed from the program defaults via the setup file. The value should be entered in percent. To get an occasional load factor of 1.5, the user would enter 50.0 Intersections are not “FULL” intersections in CAESAR II whenever the branch outside diameter is less than 0.975 times the header outside diameter. When there are multiple piping codes in the same piping job, and a piping code change occurs at an intersection, if the intersection is completely defined with three pipes framing into the intersection then the piping code used to generate the SIF equations will be that one associated with the first header pipe framing into the intersection. If the intersection is only partially defined, then the piping code will be selected from the first pipe framing into the intersection point. The material, thermal expansion, and modulus of elasticity data are for the B31 piping codes. Users may enter their own material and thermal expansion properties if desired. There is a small difference between USE_WRC330 and REDUCED_INTERSECTION =WRC330. The first applies for all full and reduced intersections that are not welding tees or reinforced tees. The latter applies only for reduced fittings that are not welding tees or reinforced fabricated tees. A fitting is reduced when d/D is less than 0.975. The Bonney Forge SIF Data came from the technical flyer: “Bonney Forge Stress Intensification Factors” Bulletin 789/SI-1, Copyright 1976. The ASME piping codes primarily combine moments for thermal expansion stresses. When there is any tendency for large axial forces to exist in the pipe these code equations are not adequate. An example of this is for a buried, or partially buried pipe. Here the axial stresses can be very high. B31.4 directs the user to compute a longitudinal stress for completely restrained pipe. CAESAR II allows the user to specify just how much of the pipe is buried. This longitudinal stress is then added to the stress calculations for thermal and will contribute to a failure prediction that might have otherwise been ignored. Similar effects can be achieved in CAESAR II by using the axial soil restraint and telling the setup file to include F/A components in the stress calculations. Users should be aware that for any type of problem, if large axial loads are developed because of the design, the piping code may not be adequately considering it.

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Code-Specific Notes B31.1 Pressure stiffening is implemented by default. Users may deactivate pressure stiffening for B31.1 runs by entering the parameter USE_PRESSURE_STIFFENING=NO in the setup file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. B31.1 does not by default add F/A into the stress calculation. F/A and the pressure stresses are added to the bending stress (whether the tensile or compressive component of bending), to produce the largest longitudinal stress component. This is true for all codes insofar as the addition of axial and pressure terms are concerned. The user can cause CAESAR II to include the axial force terms into the code stress by inserting the parameter ADD_F/ A_IN_STRESS=YES to the setup file. The F/A forces discussed here are structural forces developed in the piping independent of pressure PD/4t forces. In 1980 B31.1 added a reduced branch stress intensification factor equation to Appendix D. This equation came directly from ASME Section III. B31.1 continued however to use the effective section modulus calculation for the branch. The ASME Section III rules clearly stated that the branch section modulus, NOT the effective section modulus should be used with the new SIF. B31.1’s using of the effective section modulus produced unnecessarily high calculated stresses. This error was corrected in the 1989 version of B31.1. Prior to Version 3.0 CAESAR II users had two options: Use the pre-1980 version of the B31.1 SIF rules. Use the very conservative, post-1980 B31.1 SIF rules. In version 3.0 (and later) these options also exist, except that the section modulus problem is corrected. For users that wish to run version 3.0 (and later) just like they ran version 2.2, i.e. without the section modulus correction, they can do so by putting the parameter: B31.1_REDUCED_Z_FIX=NO in the setup file. The reduced intersection branch SIFs were not intended for reinforced or welding tees. Conservative results are produced, but the original researchers did not intend for the SIFs to be used for these fittings. The CAESAR II user can disable the reduced branch fitting calculations for reinforced or welded tees by putting the parameter NO_REDUCED_SIF_FOR_RFT_AND_WLT in the setup file. This will produce less conservative results, but can, in some cases be justified. B31.1 102.3.2 (c) tells the user to divide the allowable stresses coming from the stress tables in Appendix A by the applicable weld joint factors listed in Para. 102.4.3. Stress allowables for B31.1 are calculated from: Expansion Allowable =

f [ (1.25/Eff)(Sc+Sh) - Sl ]

Sustained Allowable =

Sh/Eff

Occasional Allowable =

Sh/Eff * (Occ)

Where: f

=

Cyclic reduction factor

Eff =

Longitudinal Weld Joint Efficiency

Sc =

Cold Allowable Stress

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Sh =

Hot Allowable Stress

Sl =

Sustained Stress

Occ =

Occasional Load Factor (Default = 1.15)

99

Inplane and outplane stress intensification factors for intersections are kept the same in the B31.1 stress calculation. The B31.1 criteria “B” length for closely spaced miters is not checked by CAESAR II. For reducers B31.1 states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2) Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[ length / (D1-D2)/2 ] Note:

Alpha cannot exceed 60° and the larger of D1/t1 and D2/t2 can not exceed 100.

B31.3 Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. Inplane and outplane stress intensification factors for intersections are kept separate and unique. Since the B31.3 piping code gives the equation for the expansion stress explicitly, and since that equation does not include the longitudinal stress due to axial loads in the pipe, CAESAR II does not include the F/A component of the stress in the expansion stress equation. (The code also says that the user may wish to add in the F/A component where it may be significant.) Users can change this by placing the parameter: ADD_F/ A_IN_STRESS=YES to the setup file. The F/A longitudinal stress component is by default added to the code stress component for all other stress categories. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. No differentiation is made between socket welds with and without “undercut.” Codes that do differentiate use 1.3 for socket welds with no undercut, and 2.1 for all others. An SIF of 1.3 is used for all B31.3 socket welds (unless a fillet weld leg length is specified). Stress allowables for B31.3 are calculated from: Expansion Allowable =

f [ (1.25/Eff)(Sc+Sh) - Sl ]

Sustained Allowable =

Sh/Eff

Occasional Allowable =

Sh/Eff * (Occ)

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Where: f

=

Cyclic reduction factor

Eff =

Weld Joint Efficiency (Only for pre-1980 B31.3)

Sc =

Cold Allowable Stress

Sh =

Hot Allowable Stress

Sl =

Sustained Stress

Occ =

Occasional Load Factor (Default = 1.33)

For B31.3 the flag ALL_STRESS_CASES_CORRODED=NO flag in the setup file returns the corroded stress calculations to the way they were performed in the 2.2 version of CAESAR II. The corrosion is removed from the sustained and occasional stress calculations. See Chapter 2 of the Technical Reference Manual for the setup file parameter B31.3_SUS_CASE_SIF_FACTOR=. This value can have a considerable impact on the sustained case stress calculations. Pressure effects on miters are allowed in the B31.3 piping code. For reducers B31.3 states that the Flexibility Factor is 1.0. The code also states that SIF is 1.0.

B31.4 Pressure stiffening is automatically included as directed per the code. Users may turn pressure stiffening off by including the parameter USE_PRESSURE_STIFFENING=NO in the setup file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. Inplane and outplane stress intensification factors for intersections are kept separate and unique. The Allowables for B31.4 are calculated from: Expansion Allowable =

(0.72)(Sy)

Sustained Allowable =

(0.75)(0.72)(Sy)

Occasional Allowable =

(0.8)(Sy)

Operating Allowable = axial stress is tensile

(0.9)(Sy) if the axial stress is compressive, no code check done if the

Where: Sy

=

Specified Minimum Yield Stress

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101

B31.4 does not use EFF, (found in the Allowable Stress Auxiliary field). The minimum yield stress is all that is required to compute flexibility stress allowables. B31.4 has no provision for using an effective section modulus calculation at intersections. B31.4 does not include a provision for the liberal allowable. This particular option is not used for B31.4 stress allowable calculations. The occasional load factor (used in the other piping codes for determining the allowable stress for occasional load sets) is not used in B31.4, as the allowable stress is expressly given as 0.8 times the minimum yield stress. CAESAR II assumes that 419.6.4(b) establishes a requirement for the allowable operating stress at 90% of Sy; when the net axial stress is compressive (i.e., when longitudinal pressure stresses can be ignored in underground pipes). The last sentence in the paragraph establishes that: “Beam bending stresses shall be included in the longitudinal stress for those portions of the restrained line which are supported above ground.” CAESAR II users have two options for including this axial stress in their analyses: 1

Include axial friction restraints and include the ADD_F/A parameter into the setup file. Set the “fac” value to 0.001 to indicate that the line is buried, so longitudinal pressure stresses are not present, so the hoop stress component must be considered.

2

Use the “fac” value to have CAESAR II compute the “axially-restrained” stress and include it during stress calculations. If a nonzero “fac” value is entered, the pressure plus axial loads in the pipe are multiplied by (1-Fac). This gives a more realistic estimation of the axial stress in the pipe when the user has included both of the effects above.

Users should note that paragraph 419.6.4(b) requires 1) the reduction of the axial expansion stress by the product of Poisson’s ratio and the pressure hoop stress, and 2) the addiction of the hoop stress to the axial stress. The latter represents the calculation of stress intensity when the axial stress is compressive, implying that there is no longitudinal pressure stress in buried pipe (the pressure loads are transmitted directly to the soil). CAESAR II handles this case in the Operating Load Case, where the hoop stress is added in and the allowable stress is set to 0.9 Sy whenever the axial stress is compressive. If “fac” is set to 0.001, the piping element is considered to be buried, so the longitudinal pressure stress is replaced by the product of Poisson’s ratio and the hoop stress, in keeping with the spirit of paragraph 419.6.4(b). “fac” is automatically set to 0.001 when B31.4 pipe is sent through CAESAR II's buried pipe modeler. The stress due to axial force will also be included for these elements. The “fac” variable should probably not be set to 1.0 with B31.4 and thermal expansion cases where the user is going from one thermal state to another state, i.e. where the case is of the form: DS1-DS2, and both DS1 and DS2 contain temperatures. In this case the thermal expansion used in the restrained pipe calculation comes from the last thermal specified in the load case definition. In the example above the thermal expansion associated with the DS2 load case. The base hoop stress on OD flag in the setup file is used by B31.4 when the hoop stress is calculated for the restrained pipe longitudinal stress calculation. The default is to base the hoop stress calculation on the average diameter, and the equation PD/2t. In the mechanical stress calculations the hoop stress is based on the inside diameter. (This is the hoop stress that is printed in the 132 column CAESAR II stress report.) For reducers B31.4 states that the Flexibility Factor is 1.0. The code also states that SIF is 1.0.

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B31.4 Chapter IX Chapter IX presents the offshore requirements of the B31.4 code. All Stress Intensification Factors, Flexibility Factors, and section moduli are calculated exactly as in the standard B31.4 Code. Stress calculations are made using the uncorroded wall thickness. Operating, Sustained, or Occasional load cases are treated identically (there is no provision for a code check for an Expansion load case, so no Expansion cases are generated under this code). For these load cases, three stress calculations are done, each with a different allowable. The stress calculation causing the highest percent of allowable is reported in the stress report, along with its specific allowable. These stress checks are: Hoop Stress:

Sh <= F1 Sy

Longitudinal Stress:

|SL| <= 0.8 Sy

Equivalent Stress:

Se <= 0.9 Sy

Where: Sh = (Pi – Pe) D / 2t Pi = internal pressure Pe = external pressure D = outer diameter t = wall thickness F1 = hoop stress design factor (0.60 or 0.72, see Table A402.3.5(a) of the B31.4 Code) Sy = specified minimum yield strength SL = Sa + Sb or Sa - Sb, whichever results in greater stress value Sa = axial stress (positive tensile, negative compressive) Sb = bending stress Se = 2[((SL - Sh)/2)2 + St2]1/2 St = torsional stress

B31.5 For reducers B31.5 states that the Flexibility Factor is 1.0. The code also states the SIF is 1.0.

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B31.8 Pressure stiffening is automatically included as directed per the code. Users may turn pressure stiffening off by including the parameter USE_PRESSURE_STIFFENING=NO in the setup file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. No differentiation is made between socket welds with and without “undercut”. Codes that do differentiate use 1.3 for socket welds with no undercut, and 2.1 for all others. An SIF of 1.3 is used for all B31.8 socket welds (unless a fillet weld leg length is specified). B31.8 has no provision for using an effective section modulus calculation at intersections. The allowables used for B31.8 are Expansion Allowable

=

(0.72)(Sy)

Sustained Allowable

=

(0.75)(Sy)

Occasional Allowable

=

(0.75)(Sy)*(Occ)

Operating Allowable

=

(Sy)

Where: Occ

=

is the occasional load factor (Default=1.0)

Sy

=

is the specified minimum yield stress

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In B31.8 Table E1, note 8 to this table allows ii=io. This produces more conservative results and is recommended by Rodabaugh in WRC 329, and so is the CAESAR II default for SIFs. The only time the SIFs are kept different is when d/D is between 0.5 and 1.0. In this case the out-of-plane stress intensification factor as computed is multiplied by 1.5. See note 10 to Table E1. In this case ii = 1.5*io. Where d/D is less than 0.5 there is no change to the SIF. (ii=io). ‘ There is no “liberal allowable” calculation for B31.8. The OCC occasional load default for B31.8 is 1.0. There is no provision in B31.8 for occasionally acting loads, and the stress summation discussion in 833.4(c) includes: “the longitudinally bending stress due to external loads, such as weight of pipe and contents, wind, etc....” There is no differentiation between the weight load and the wind load. The user must interpret the intention of the code in this case. For reducers B31.8 states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* (D2/t2)^2/3 Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[ length / (D1-D2)/2] Note: exceed 100.

Alpha cannot exceed 60° and the larger of D1/SQRT(t1) and D2/SQRT(t2) can not

B31.8 Chapter VIII Chapter VIII presents the offshore requirements of the B31.8 code. All Stress Intensification Factors, Flexibility Factors, and section moduli are calculated exactly as in the standard B31.8 Code. Stress calculations are made using the uncorroded wall thickness. Operating, Sustained, or Occasional load cases are treated identically (there is no provision for a code check for an Expansion load case, so no Expansion cases are generated under this code). For these load cases, three stress calculations are done, with different allowables. The stress calculation causing the highest percent of allowable is reported in the stress report, along with its specific allowable. These stress checks are: Hoop Stress:

Sh <= F1 S T

Longitudinal Stress:

|SL| <= 0.8 S

Equivalent Stress:

Se <= 0.9 S

Where: Sh = (Pi – Pe) D / 2t Pi = internal pressure Pe = external pressure

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105

D = outer diameter t = wall thickness F1 = hoop stress design factor (0.50 or 0.72, see Table A842.22 of the B31.8 Code) S = specified minimum yield strength T = temperature derating factor (see Table 841.116A of the B31.8 Code) Note: The product of S and T (i.e., the yield stress at operating temperature) is required in the SH field of the CAESAR II input SL = maximum longitudinal stress (positive tensile, negative compressive) Se = 2[((SL - Sh)/2)2 + Ss2]1/2 Ss = torsional stress

B31.11 Pressure stiffening is automatically included as directed per the code. Users may turn pressure stiffening off by including the parameter USE_PRESSURE_STIFFENING=NO in the setup file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. Inplane and outplane stress intensification factors for intersections are kept separate and unique. The Allowables for B31.11 are calculated from: Expansion Allowable

=

(0.72)(Sy)

Sustained Allowable

=

(0.75)(0.72)(Sy)

Occasional Allowable

=

(0.88)(Sy)

=

(0.9)(Sy) if the axial stress is compressive, no code

=

Specified Minimum Yield Stress

Operating Allowable check done if the axial stress is tensile Where: Sy

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B31.11 does not use EFF, (found in the Allowable Stress Auxiliary field). The minimum yield stress is all that is required to compute flexibility stress allowables. B31.11 has no provision for using an effective section modulus calculation at intersections. B31.11 does not include a provision for the liberal allowable. This particular option is not used for B31.11 stress allowable calculations. The occasional load factor (used in the other piping codes for determining the allowable stress for occasional load sets) is not used in B31.11, as the allowable stress is expressly given as 0.88 times the minimum yield stress. CAESAR II assumes that 1119.6.4(b) establishes a requirement for the allowable operating stress at 90% of Sy; when the net axial stress is compressive (i.e., when longitudinal pressure stresses can be ignored in underground pipes). The last sentence in the paragraph establishes that: “Beam bending stresses shall be included in the longitudinal stress for those portions of the restrained line which are supported above ground.” CAESAR II users have two options for including this axial stress in their analyses: 1

Include axial friction restraints and include the ADD_F/A parameter into the setup file. Set the “fac” value to 0.001 to indicate that the line is buried, so longitudinal pressure stresses are not present, so the hoop stress component must be considered.

2

Use the “fac” value to have CAESAR II compute the “axially-restrained” stress and include it during stress calculations. If a nonzero “fac” value is entered, the pressure plus axial loads in the pipe are multiplied by (1-Fac). This gives a more realistic estimation of the axial stress in the pipe when the user has included both of the effects above.

Users should note that paragraph 1119.6.4(b) requires 1) the reduction of the axial expansion stress by the product of Poisson’s ratio and the pressure hoop stress, and 2) the addition of the hoop stress to the axial stress. The latter represents the calculation of stress intensity when the axial stress is compressive, implying that there is no longitudinal pressure stress in buried pipe (the pressure loads are transmitted directly to the soil). CAESAR II handles this case in the Operating Load Case, where the hoop stress is added in and the allowable stress is set to 0.9 Sy whenever the axial stress is compressive. If “fac” is set to 0.001, the piping element is considered to be buried, so the longitudinal pressure stress is replaced by the product of Poisson’s ratio and the hoop stress, in keeping with the spirit of paragraph 1119.6.4(b). “fac” is automatically set to 0.001 when B31.11 pipe is sent through CAESAR II's buried pipe modeler. The stress due to axial force will also be included for these elements. The “fac” variable should probably not be set to 1.0 with B31.11 and thermal expansion cases where the user is going from one thermal state to another state, i.e. where the case is of the form: DS1-DS2, and both DS1 and DS2 contain temperatures. In this case the thermal expansion used in the restrained pipe calculation comes from the last thermal specified in the load case definition. In the example above the thermal expansion associated with the DS2 load case. The base hoop stress on OD flag in the setup file is used by B31.11 when the hoop stress is calculated for the restrained pipe longitudinal stress calculation. The default is to base the hoop stress calculation on the average diameter, and the equation PD/2t. In the mechanical stress calculations the hoop stress is based on the inside diameter. (This is the hoop stress that is printed in the 132 column CAESAR II stress report.)

For reducers B31.11 states that the Flexibility Factor is 1.0. The code also states that the SIF is 1.0.

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ASME III Subsections NC and ND Pressure stiffening is not defined by default in the Code. Users may include pressure stiffening on bends in the analysis by including the parameter USE_PRESSURE_STIFFENING=YES in the configuration file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. The minimum SIF for reinforced and unreinforced fabricated tees is 2.1. B1 and B2 are calculated according to ASME NC and ND. Equations used are shown in the Help screens for B1 and B2. If in the odd situation where the user is using the ASME III piping code, and is running dynamics, and is calling one of the dynamic case expansion, and has the liberal allowable flag turned on, the liberal allowable request will be ignored, and the difference between Sh and Sl will not be added to the expansion allowable. This is more of a programming decision than an interpretation of the piping code or a recommendation for doing dynamic analysis. Inplane and outplane stress intensification factors are the same for the ASME Section III piping codes. When using USE_WRC330 with ASME NC or ND, for all intersections that are not welding tees or reinforced fabricated tees, the approximate section modulus is used for the stress calculations, i.e. pi*r2*t. This includes all reduced intersections and all d/D ratios. Users that DO NOT wish to use the branch stress intensification factors found in Appendix D of the Code for welding and reinforced reducing tees, should put the flag: NO_REDUCED_SIF_FOR_RFT_AND_WLT in the setup file. The allowables for ASME III NC and ND are computed from Expansion Allowable =

f( 1.25Sc + 0.25Sh) + (Sh-Sl)

Sustained Allowable =

1.5Sh (If not at an intersection)

Occasional Allowable = 1.8Sh not greater than 1.5Sy (If OCC=1.2); 2.25Sh not greater than 1.8Sy (If OCC=1.5); 3.0Sh not greater than 2.0Sy (If OCC=2.0) Where: f

=

Cyclic reduction factor

Sc =

Cold Allowable

Sh =

Hot Allowable

Sl =

Sustained stress from PD/4t+0.75iMb.

Sy =

Material Yield Stress

OCC

=

Occasional factor from the CAESAR II configuration file

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For two pipe intersections, i.e. butt welds, socket welds, etc. B1 and B2 factors are 1.0. If the ratio of the average branch to average run radius is less than 0.5 then the reduced intersection rules are applied to the B1 and B2 calculations regardless of the intersection type. If the reduced intersection rules do not apply then the rules for butt welded fittings are used, i.e. B2b=

0.4 * (R/T)**2/3 but not < 1.0,

B2r =

0.5 * (R/T)**2/3 but not < 1.0.

Users can always modify the B1 and B2 values for any node in the SIF&TEE Auxiliary field. B1 and B2 values modified on an auxiliary field only apply for that element, regardless of whether the node is an intersection or not. When r/R < 0.5 the following equations are used for B1 and B2: B2b=

0.50 C2b but not < 1.0,

B2r =

0.75 C2r but not < 1.0,

C2b=

3(R/T)**2/3 (r/R)**1/2 (t/T)(r/rp), but not < 1.5

C2r =

1.15(r/t)**1/4 but not < 1.5.

WRC329 does result in smaller branch SIFs than ASME NC and ND, and the same run SIFs. The branch SIFs are smaller by a factor of 2. This is when d/D<0.5, and WRC 329 corrects the Mob inconsistency when d/D is between 0.5 and 1. Thus in the lower ranges of d/D ratios WRC 329 is less conservative than the present codes and in the higher ranges WRC 329 is more conservative than the present codes. The Pvar value in the allowable stress spreadsheet is for the DIFFERENCE between the operating pressure and Pmax to be used in eq 11. This is because of the way the occasional stresses are formed in CAESAR II, i.e. the direct addition of two stress components. So we are computing the sustained stress (including pressure) and adding it to the occasional stress, including the stress difference between the operating pressure and the peak pressure that is to be used in the ASME occasional stress equation 11. The equations 10 or 11 are satisfied by using as the allowable for the iMc/Z stress as the maximum of either f(1.25Sc + 0.25Sh) or f(1.25Sc + 0.25Sh) + (Sh-Sl) where Sl is the sustained stress as defined by equation 11 as PDo/4tn+0.75iMa/Z. The CAESAR II approach taken for ASME NC and ND for moment summations at intersections to satisfy equations 8 and 9 is the same as for equations 10 and 11, i.e. the SRSS of the moments at each end of the pipe framing into the intersection is found. The cumulative moment summation rules for a single intersection as per NB 3683.1 are not adhered to. In addition the effective section modulus rules of NC and ND are used for all intersection stress calculations, i.e. for equations 8 and 9. (The NB subsection is used to get the values for B1 and B2 only, and to compute the local flexibility if requested) Because of this approach in CAESAR II, there is no allowable calculated for intersection points and sustained or occasional loads. The sustained case SIF factor is not used in the ASME class 2 or 3 calculations. For reducers NC states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2)

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109

Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[ length / (D1-D2)/2 ] Note: Alpha cannot exceed 60 º. The larger of D1/t1 and D2/t2 cannot exceed 100. B1=.5 if alpha

30 º, 1.0 if 30 º < alpha

60 º B2 = 1.0.

For reducers ND states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2) Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[ length / (D1-D2)/2 ] Note: There is an error in the code, the code states note 12 however, they meant note 14. Alpha cannot exceed 60 º. The larger of D1/t1 and D2/t2 can't exceed 100. B1=.5 if alpha

30 º, 1.0 if 30 º < alpha

60 º B2 = 1.0.

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CANADIAN Z662 Pressure stiffening is not defined by default in the Code. Users may include pressure stiffening on bends by including the parameter USE_PRESSURE_STIFFENING=YES in the setup file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. There is no limit in Z662 for the beneficial effect of the pad on an intersection. Most codes limit the pad thickness to 1.5 times the header thickness. For Z662 CAESAR II will not limit the pad thickness. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. Inplane and outplane stress intensification factors for intersections are the same. No differentiation is made between socket welds with and without “undercut.” Codes that do differentiate use 1.3 for socket welds with no undercut, and 2.1 for all others. An SIF of 1.3 is used for all Z662 socket welds (unless a fillet weld leg length is specified). This code has no provision for using an effective section modulus calculation at intersections. The allowable stresses are computed from Expansion Allowable =

(0.72)(Sy)(T)

Sustained Allowable =

(Sy)(Fac)(T)(L)

Occasional Allowable =

(Sy)(Fac)(T)(Occ)(L)

Operating Allowable =

0.9(Sy)(T) If pipe is buried and axial stress is compressive

=

(Sy)(T) If pipe is not buried and axial stress is compressive

Where: Sy =

Specified Minimum Yield Stress

Fac =

Construction Design Factor

T

Temperature De-rating Factor

=

Eff =

Longitudinal Weld Joint Efficiency

Occ =

Occasional Load Factor (=1.0)

L

Location Factor

=

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111

CAESAR II assumes that Section 4.6.2 of the Z662 code establishes a requirement for the allowable operating stress of 0.9 x S x T whenever the net axial stress is compressive in the absence of bending stress, and an allowable operating stress of S x T when the net axial stress is compressive in the presence of bending stress. Users should note that Section 4.6.2 requires 1) the reduction of the axial expansion stress by the product of poisson’s ratio and the pressure hoop stress, and 2) the addition of the hoop stress to the axial stress. The latter represents the calculation of stress intensity when the axial stress is compressive, implying that there is no longitudinal pressure stress in buried pipe (the longitudinal pressure thrust loads are transmitted directly to the soil). CAESAR II handles these requirements, in the OPERATING load case, in the following manner: 1

If FAC is set to 1.0, the implication is that the piping system is fully restrained (in the axial direction) as described in Section 4.6.2.1, and the operating stress is calculated as: Sh + E a (T2 - T1) - v Sh < 0.9 S x T

2

If FAC is set to 0.001, the implication is that the piping system is buried, but the soil supports are modeled (rather than just assumed to be fully rigid). This setting removes the longitudinal pressure stress from the equation (as described above), takes bending stresses into consideration, as required by Section 4.6.2.2.1. In this case, the operating stress is calculated as: Sh +Fax/A + Sb - v Sh < S x T

3

If FAC is set to 0.0, the implication is that the piping system is either not restrained, or is a “freely spanning” or “above ground” portion of a restrained line, as described in Section 4.6.2.2.1. In this case, the longitudinal pressure stress is restored, so this formula only comes into effect if the net axial stress (including pressure) is compressive, in which case the operating stress is calculated as: Sh +Slp + Fax/A + Sb < S x T

4

For those elements for which the net axial stress is longitudinal, no operating code stress check is done.

5

Users should note that CAESAR II does not check for buckling, as required by Section 4.6.2.2.2.

For reducers Z662 states that the Flexibility Factor is 1.0. The Code also states that the SIF is 1.0.

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NAVY 505 Pressure stiffening is not defined by default in the Code. Users may include pressure stiffening on bends in the analysis by including the parameter USE_PRESSURE_STIFFENING=YES in the setup file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. Navy 505 has no provision for using an effective section modulus calculation at intersections. Inplane and outplane stress intensification factors for intersections are the same. Navy 505 has no provision for a “liberal allowable,” i.e. adding the difference between Sh and Sl to the allowed expansion stress range. This flag in the control parameter spreadsheet has no affect on 505 runs. Navy 505 does use Eff in computing the cold and the hot allowable. The use of this parameter is subject to some speculation however. Navy 505 has no specific allowable for occasional loads. An occasional load factor, similar to B31.1’s will be used, and the occasional allowable calculated from kSh. The allowable stresses for Navy 505 are calculated from: Expansion Allowable =

f/Eff(1.25Sc + 0.25Sh)

Sustained Allowable =

Sh/Eff

Occasional Allowable =

Sh/Eff * Occ

Where: f

=

Cyclic reduction factor

Eff =

Joint Efficiency (Not explicitly in the Code)

Sc =

Cold Allowable Stress

Sh =

Hot Allowable Stress

Occ =

Occasional Load Factor (Default=1.15)

The B31.3_SUS_CASE_SIF_FACTOR can be used for 505 to multiply the stress intensification factors for sustained and occasional loads to be more in line with the current B31.1 practice.

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113

BS806 For BS806 the maximum hot stress case is considered to be the operating load case. Operating load case allowables are only given as per BS806 when the creep rupture strength governs the stress range allowable. See BS806 sect 4.11.2. BS806 SIFs printed are fti and fto for bends, and Bi and Bo for intersections. Pressure stiffening is not defined by default in the Code. Users may include pressure stiffening on bends by including the parameter USE_PRESSURE_STIFFENING=YES in the setup file. Modifications due to flanged ends are permitted in the code for all bend types. This includes closely and widely spaced mitered bends. There is no limit in BS806 to the beneficial effect of the pad on an intersection. Most codes limit the pad thickness to 1.5 times the header thickness. For BS806, CAESAR II will not limit the pad thickness. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. Important When there is more than one thermal case to evaluate, the following note should be read carefully concerning CAESAR II's application of BS806.

Note: Re: BS806 4.11.3.1 paragraph 2, for sectionalized systems: At this time CAESAR II only makes the moment summation on a load case by load case basis, and does not take the largest moments for an axis for any combination of load cases. The CAESAR II method was set up to allow the user to make, and combine the effects of each of the load transients that the piping system undergoes. This is, for the most part the method used in the B31/ASME piping codes. The BS806 method will be conservative in that it uses what is basically a shakedown approach and computes a single worst case moment difference. The CAESAR II approach still satisfies the shakedown theory, but computes the moment range for each different load traversed. The BS806 method of combining the maximum moment range will be more conservative. The BS806 approach also eliminates the need to know where on the pipe the stress is the highest. In reference to the moment tables in Appendix F, CAESAR II users can get the moment difference between any two load cases, but not the maximum moment difference for any of the three moment axes as requested by the sectionalized piping rules. In satisfying 4.11.3.1(a) CAESAR II uses the moment difference between the cold and the hot case to compute the stress. Only a single modulus of elasticity can be entered for a single element for each job. Different elements can have different moduli of elasticity, but that modulus cannot be varied between load cases in the same run, i.e. cold and hot moduli of elasticity cannot be used in the same run at this time. For BS806 in 4.11.5.2 the value of “n” is always taken as 1.0., i.e. all branches are of the non-interacting type. See 4.11.4.2 for the definition of “n” for interacting branches (n is defined in the fourth paragraph of 4.11.4.2). The CAESAR II equation modeling of the BS806 SIF curves for bends is shown in the following plots.

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The BS 806 allowable stresses are calculated as follows: Expansion Allowable =

lesser of (H)(Sc)+(H)(Sh) (H)(Sc)+F

Sustained Allowable =

Sy

Occasional Allowable =

(Sy)(Occ)

Operating Allowable =

S avg rupture at design temperature

Where: H =

Multiplication Factor (0.9 or 1.0 from CAESAR II)

Sc =

0.2% proof stress at room temperature

Chapter 6 Technical Discussions

Sh =

0.2% proof stress at design temperature

F

Mean stress to failure in design life at design temperature.

=

Occ =

115

Occasional Load Factor (Default=1.0)

The pressure calculation at intersections is made as required in BS806 4.8.5.1 Eq. (17). The pressure stress as per 17 is computed and then combined with the bending and torsional moments at each of the intersection ends 1, 2 and 3 respectively. The “m” factor is computed as required with a value of n=1, i.e. for non-interacting intersections.

BS806 does not make mention of reducers for SIF calculations.

Swedish Method 1 and 2 Pressure stiffening is not defined by default in the Swedish Code. Users may include pressure stiffening on bends in the analysis by including the parameter USE_PRESSURE_STIFFENING=YES in the setup file. Modifications due to flanged ends are permitted in the code for all bends providing the bend is not a widely spaced miter. The Swedish Method 1 cannot take advantage of the WRC330 recommendations. WRC 330, if requested is ignored. The Swedish Method 1 has no provision for using an effective section modulus calculation at intersections. Inplane and outplane stress intensification factors for intersections are kept the same. The Swedish Code item 9 is dealt with as a US tapered transition. Also items 10 and 11 in the Swedish table 9:2 correspond to items 8 and 9 in the CAESAR II nomenclature. The Allowable Stress for Method 1 is calculated from:

Sber

=

lesser of Sh F

Allowable

=

(Fac)(Sber) / 1.5

= = =

Yield stress at temperature Creep rupture stress at temperature Usually 1.5, for prestressed pipe 1.35.

Where: Sh F Fac

The Allowable Stress for Method 2 is calculated from: Expansion Allowable

=

f ( 1.17S1 + 0.17S2 )

Sustained Allowable

=

Sh

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CAESAR II Technical Reference Manual

Occasional Allowable

=

Sh * Occ

Where: f

=

Cyclic reduction factor

S1 =

lesser of Sc 0.267Sy

S2 =

lesser of Sh 0.367Sy

Sc =

Allowable stress at room temperature (Stn2)

Sh =

Allowable stress at design temperature (Stn1)

Sy =

Ultimate tensile strength at room temperature

Occ =

Occasional Load Factor (Default=1.2)

If the weld is ground flush inside and out then the SIF of a girth butt weld can be taken to be 1.0. A weld ID = 1, informs CAESAR II that the weld is finished and ground flush, and will result in a girth butt weld SIF of 1.0. Swedish methods 1 and 2 Beta in the code is entered in the Pvar field on the Allowable Stress Auxiliary screen. Pvar is entered in percent, i.e. 10.0 for ten percent. The default if no value is entered is 10 percent. Limits on the reasonable beta’s that users may enter for the Swedish piping code is 0.1 to 25%. Anything entered less than 0.1 will be taken to be 10% and anything entered greater than 25% will be taken to be 25%. If no value is entered then beta will default to 10%. Note that 10% is entered in the Pmax field as 10.0. This applies equally for Swedish Method 1 and Method 2. The USE_PDo/4t line for the setup file causes the Swedish method 1 code compliance to use the thin walled equations as given in the codes for stress calculations. The user of Swedish Method 1 should note that implied in the CAESAR II allowable calculation is the assumption that the SIGMA(tn) multiplier is 1.5 for piping that is not prestressed. Users of prestressed pipe (i.e. cold sprung) should change “Fac” on the Allowable Stress Auxiliary field to be 1.35 as directed in the Swedish code. Note: The corroded section modulus is used for all stress calculations as per the definition of Di in the Swedish code. The default occasional load factor for Swedish Method 2 is 1.2. The Swedish piping codes allow the pad thickness on an intersection to reduce stresses up to pad thickness of 2.5 times the header wall thickness. This is greater than most code’s value of 1.5 times the header wall thickness. For reducers the Swedish piping codes states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2)

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117

Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[length / (D1-D2)/2 ]

B31.1 (1967) The 1967 B31.1 piping code uses ii=io for full sized intersections for both the header and the branch, and for reduced intersections uses ii=0.75io + 0.25 for both the header and the branch. Pressure stiffening is not defined by default. Users may activate pressure stiffening for B31.1 (1967) runs by entering the parameter USE_PRESSURE_STIFFENING=YES in the setup file. Modifications resulting from flanged ends are permitted in the code for all bends providing the bend is not a widely spaced miter. The SIF for a girth butt weld is taken as 1.0, as this was Markl’s original basis for SIFs. No differentiation is made between socket welds with and without “undercut.” Codes that do differentiate use 1.3 for socket welds with no undercut, and 2.1 for all others. An SIF of 1.3 is used for all socket welds (unless a fillet weld leg length is specified). The B31.1 (1967) allowable stresses are computed from: Expansion Allowable

=

f [ (1.25/Eff)(Sc+Sh) - Sl ]

Sustained Allowable

=

Sh/Eff

Occasional Allowable

=

Sh/Eff * Occ

Where: f

=

Cyclic reduction factor

Eff

=

Longitudinal Weld Joint Efficiency

Sc

=

Cold Allowable Stress

Sh

=

Hot Allowable Stress

Sl

=

Sustained Stress

Occ

=

Occasional Load Factor (Default=1.15)

SC

=

the yield stress at room temperature, referred to as Re in the code.

SH1

=

the yield stress at design temperature, referred to as Re (um) in the code.

SH2

=

not used

SH3

=

not used

Stoomwezen

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CAESAR II Technical Reference Manual

FN = the average creep stress to produce one percent set, referred to as Rrg in the code. F2 is the average creep tensile stress to produce rupture, referred to as Rmg in the code. F3 is the minimum creep tensile stress to produce rupture, referred to as Rmmin in the code. EFF

=

the cyclic reduction factor, referred to as Cf in the code.

SY

=

the tensile strength at room temperature, referred to as Rm in the code.

FAC for details.

=

a constant whose value is either 0.44 or 0.5. Refer to Stoomwezen Section 5.2

PVAR

=

the Cm coefficient in the code whose value is usually 1.0.

Stoomwezen does not make mention of reducers for SIF calculations.

RCC-M Subsection C and D Pressure stiffening is not defined by default in the code. Users may include pressure stiffening on bends in the analysis by including the parameter. USE_PRESSURE_STIFFENING=YES in the configuration file. Modifications resulting from flanged ends are permitted in the code providing the bend is not a widely spaced miter. In-plane and out-of-plane stress intensification factors are the same for these piping codes. Users who do not wish to use the stress intensification factor for branch connections found in Figure C3680.1 of the code for welding and reinforced reduced tees, should set NO_REDUCED_SIF_FOR_RFT_ AND_WLT=YES in the configuration file. The allowables for RCC-M C and D are computed from: Expansion Allowable =

F (1.25Sc + 0.25Sh)+(Sh - SSl)

Sustained Allowable =

Sh

Occasional Allowable =

OCC + Sh (Defaults to 1.2, Level B) (Use OCC = 1.8 for Level C) (Use OCC = 2.4 for Level D)

Where: F

=

Cyclic reduction factor

Sc

=

Cold allowable

Sh

=

Hot allowable

Ssl

=

Sustained stress (PD/4t + 0.75i Mb/Z)

OCC =

Occasional factor from the CAESAR II configuration file)

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119

The Pvar value in the allowable stress spreadsheet is for the DIFFERENCE between the design pressure and Pmax to be used in equation 10. Equations 7 or 8 are satisfied by using as the allowable for the i Mc/Z stress the maximum of either F (1.25Sc + 0.25Sh) or F (1.25Sc + 0.25Sh) + (Sh - Ssl) where Ssl is the sustained stress as defined by equation 6.

For reducers RCC-M states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2) Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[ length / (D1-D2)/2 ] Note:

Alpha cannot exceed 60° and the larger of D1/t1 and D2/t2 cannot exceed 100.

CODETI Modifications resulting from flanged ends are permitted in the code for all bends, including widely spaced miters. Inplane and outplane stress intensification factors of intersections are kept separate and unique. Since the CODETI piping code gives the equation for the expansion stress explicitly, and since that equation does not include the longitudinal stress due to axial loads in the pipe, CAESAR II does not include the F/A component of the stress in the expansion stress equation. Users can change this by setting ADD_F/A_IN_STRESS=YES to the configuration file. The F/A longitudinal stress component is by default added to the code stress component for all other stress categories. Stress allowables for CODETI are calculated from Expansion Allowable =

F [1.25 (Sc + Sh)] - Sl

Sustained Allowable =

Sh

Occasional Allowable =

OCC x Sh

Where: F

=

Cyclic reduction factor

Sc

=

Cold allowable stress

Sh

=

Hot allowable stress

Sl

=

Sustained stress

OCC = Occasional load factor from configuration (defaults to 1.15)

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Pressure stiffening of bends is automatically included as directed by the code. Users may deactivate it by setting the parameter USE_PRESSURE_STIFFENING=NO in the configuration file. Flexibility coefficients and stress intensification factors are phased in for bends with an included angle between 15° and 45°. Their value is 1.0 for smaller than 15° bends. The stress intensification factor of fabricated tees having an angle of incidence other than 90° are increased by dividing them by (sin a)3/2. Recommended occasional load factors are 1.15, 1.2, and 1.3, as per Code Table C3.3. CODETI requires that when “the design temperature is such that the creep characteristics are determinant, and if a section of the piping presents locally weaker characteristics,” the sum of the primary and secondary stresses must not exceed the value FF (from Section C1.4.3). This requirement has not been implemented in CAESAR II and has been left to the user to verify. For reducers CODETI states that the Flexibility Factor is 1.0. The code also states that SIF is 1.0.

Norwegian (TBK 5-6) Pressure stiffening of bends is required for flexibility factors only and is done that way, by default. Users may deactivate pressure stiffening completely by setting USE_PRESSURE_STIFFENING=NO in the configuration file. Pressure stiffening may be activated for stress intensification factors as well by setting USE_PRESSURE_-STIFFENING=YES. The Norwegian Code does not by default add F/A into the stress calculation. The user can cause CAESAR II to include the axial force term into the code stress by setting ADD_F/A_IN_STRESS=YES in the configuration file. The code uses a circumferential weld strength factor (Z) when calculating longitudinal pressure stress. This value is entered as EFF. The cyclic reduction factor should be calculated as F = (7000/Ne)0.2 (where Ne is the number of anticipated cycles), and may be as high as 2.34, but shall not be greater than 1.0 when Rm governs the expansion stress allowable. In-plane and out-of-plane stress intensification factors for bends and intersections are kept the same in the stress calculation. Stress allowables for the Norwegian Code are Expansion allowable =

Sr + F2 - SSUS

Sustained allowable

F2

=

Occasional allowable =

Occ x F2

Where: Sr = Minimum of 1.25F1 + 0.25F2; Fr x Rs - F2; or Fr (1.25 R1 + 0.25 R2) (The latter for higher temperatures; above 425°C for austenitic stainless steel, or above 370°C for other materials) F2 = OCC

Hot allowable stress (entered in Sh) =

Occasional load factor from the configuration file (defaults to 1.2)

Chapter 6 Technical Discussions

SSUS =

Sustained stress

F1 =

Allowable stress at ambient (entered in Sc)

Fr =

Cyclic reduction factor

Rs =

Permissible extent of stress for 7000 cycles (from Code Table 10.2)

R1 =

Smaller of F1 and 0.267 RM

R2 =

Smaller of F2 and 0.367 RM

Rm =

Ultimate tensile strength at room temperature

121

Stress intensification factors for fitting types 6 (branch with raised edge radius), 7 (branch on locally thickened pipe), 13 (conical reducer with knuckles), and 14 (reducer without knuckles) have not been implemented in CAESAR II and are the responsibility of the user to enter manually. The Norwegian code offers an alternative stress analysis method in Appendix D. CAESAR II does not implement that method. For reducers the Norwegian code states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2) Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end.

FDBR The FDBR code is similar to B31.1 in most aspects. However, the following differences should be noted. For reinforced tees, FDBR limits the pad thickness to a maximum equal to the header thickness. If a pad thickness greater than the header thickness is entered, the program overrides it with the header thickness. Reduced intersections are treated as in ASME NC, not as in B31.1. The SIF values for butt welds differ from B31.1. FDBR uses either 1.0 or 1.8, depending on the thickness. FDBR requires the use of the Hot Modulus of Elasticity in the flexibility analysis. Additionally, the computation of the Expansion Case Allowable Stress incorporates the ratio of Ehot to Ecold. The user can override the program computed ratio by manually entering it in the FAC field. For reducers FDBR states that the Flexibility Factor is 1.0. The code also states that SIF is: 2.0 max or 0.5 + .01*alpha* SQRT(D2/t2) Where D1 and t1 are the diameter and thickness of the large end and D2 and t2 are the diameter and thickness of the small end. Alpha is the reducer cone angle in degrees. Where: Alpha = atan[ length / (D1-D2)/2 ]

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Note:

Alpha cannot exceed 60° and the larger of D1/t1 and D2/t2 cannot exceed 100.

BS 7159 The BS 7159 Code for Fiberglass Reinforced Plastic (FRP) Pipe requires that a single load case (OPE) be evaluated. For that case, the following combined stress requirements must be met: If Sx is tensile:

S x2 + 4 ( S s ) 2 < Sh and

S

2

E 2 + 4S s < S h -----Ex

or, if Sx is compressive:

E S – v S x < S h -----Ex and

S x < 1.25S h Where: 2

2

2

2

P ( Dm ) ( i si Mi ) + ( i xo Mo ) S x = ---------------- + ---------------------------------------------------( 4t d ) Z or

P ( Dm ) ( i xi M i ) + ( ix o Mo ) F x S x = ---------------- – ----------------------------------------------------- – -----( 4t d ) A Z

MT S s = ----------(2 Z )

mP ( Dm ) S = --------------------2t d

for straight pipe

(if

F x P( D m ) ------ > ---------------A ( 4t d )

, and it is compressive)

Chapter 6 Technical Discussions

2

123

2

mP ( Dm ) ( i M i ) + ( i Mo ) S = --------------------- + ------------------------------------------------2t d Z 2

for bends 2

mP ( Dm ) ( i xi Mi ) + ( i xo M o ) S = --------------------- + ----------------------------------------------------2t d Z

for tees,

Where Dm & td are always for the run pipe

BS 7159 allowables are based on material design strain ed . Therefore allowable stresses differ in the axial and hoop directions by the ratio of the axial and hoop moduli of elasticity: Sh = (dEx

SHOOP = ((dEx) (Eh/Ex)

The ratio Eh/Ex is entered in the allowable stress Eff field; if omitted, it defaults to 1.0 (isotropic material). Pressure stiffening of bends is done assuming the bends are fully pressurized up to the design strain of the components (as per the code requirements). This can be deactivated by setting USE_PRESSURE_STIFFENING = NO in the configuration file. BS 7159 does not by default add F/A into the stress calculation (unless this puts an element into compression as described above). The user can cause CAESAR II to include the axial force term into the code stress by setting ADD_F/A_IN_STRESS = YES in the configuration file. The fatigue factor Kn is used inversely relative to the cyclic reduction factor in most codes, so its value should be greater than or equal to 1.0 (allowable stress is divided by this number). Kn is calculated as: Kn = 1.0 + 0.25 (As/ n) (Log10(n) - 3.0) Where: As = n

n

stress range during fatigue cycle

=

maximum stress during fatigue cycle

=

number of cycles during design life

Kn is entered in the Cyclic Reduction Factor field(s).

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BS 7159 requires that the temperature of the pipe material be considered as being typically only 80% 85% of the difference between the fluid and the ambient temperatures. This reduction factor K is entered in the allowable stress FAC field; if omitted, it defaults to 1.0. The stress intensity and flexibility factors of bends vary based on laminate type: All chopped strand mat (CSM) construction with internal and external surface tissue reinforced layer Chopped strand mat (CSM) and woven roving (WR) construction with internal and external surface tissue reinforced layer Chopped strand mat (CSM) and multi-filament roving construction with internal and external surface tissue reinforced layer The laminate type may be entered in the Bend Type field, or a type default may be set in the Special Execution Parameter screen. BS 7159 does not make mention of reducers for SIF calculations.

UKOOA The UKOOA (United Kingdom Offshore Operators Association) Specification and Recommended Practice for the Use of GRP Piping Offshore is similar in many respects to the BS 7159 Code, except that it simplifies the calculational requirements in exchange for imposing more conservatism on the piping operating conditions. Rather than explicitly calculating a combined stress, the specification defines an idealized envelope of combinations of axial and hoop stresses which cause the equivalent stress to reach failure. This curve represents the plot of: ( x/

-all

)2 +

hoop

/

hoop-all

)2 - [

x

hoop

/(

x-all

hoop-all

)]

1.0

Where: x-all

hoop-all

=

allowable stress, axial

=

allowable stress, hoop

The Specification conservatively limits the user to that part of the curve falling under the line between sx-all (also known as sa(0:1)) and the intersection point on the curve where shoop is twice sx-(a natural condition for a pipe loaded only with pressure). An implicit modification to this requirement is the fact that pressure stresses are given a factor of safety (typically equal to 2/3) while other stresses are not. This gives an explicit requirement of: f1 f2 f3 LTHP

Pdes Where: Pdes =

allowable design pressure

f1

=

factor of safety for 97.5% lower confidence limit, usually 0.85

f2

=

system factor of safety, usually 0.67

f3

=

ratio of residual allowable, after mechanical loads =

a

=

b

axial bending stress due to mechanical loads

r a(0:1)

1 - (2 sab) / (r f1 LTHS)

= =

sa(0:1) / sa(2:1)

long term axial tensile strength in absence of pressure load

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=

a(2:1)

long term axial tensile strength in under only pressure loading

LTHS

=

long term hydrostatic strength (hoop stress allowable)

LTHP

=

long term hydrostatic pressure allowable

Note:

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This has been implemented in the CAESAR II pipe stress analysis software as: Code Stress a

b

(f2 /r) + PDm / (4t)

Code Allowable (f1 f2 LTHS) / 2.0

Where: P

=

design pressure

Dm

=

pipe mean diameter

t

=

pipe wall thickness

On the Allowable auxiliary screen, the product of f1 and LTHS is entered in the SH1, SH2, SH3 fields; r is entered in the F1, F2, F3 fields; f2 is entered in the EFF field; and the temperature reduction factor K (described for BS 7159 above) is entered in the FAC field – if omitted, it defaults to 1.0. K- and i-factors for bends and tees are taken from (laminate types may be entered in the Bend Type fields), and bending and pressure stresses are calculated as described in, the BS 7159 Code. Note: UKOOA refers to BS7159 for SIF calculations.

IGE/TD/12 CAESAR II performs calculations as per the IGE/TD/12 Edition 2 code requirements. The complexity of these requirements far exceeds what can be described here. It is recommended that the user acquire a copy of this code from the International Institution of Gas Engineers & Managers or request COADE’s supplementary IGE/TD/12 documentation. Note: The current implementation of the IGE/TD/12 code has yet not been granted approval for use on Transco projects.

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Det Norske Veritas (DNV) This code is entitled “Rules for Submarine Pipeline Systems.” The Allowable Stress Design (ASD) provisions of the code are implemented here, rather than the limit state requirements. Since the DNV code does not provide any guidance on Stress Intensification Factors, Flexibility Factors, or section moduli; these are calculated as per the B31.1 Power Code (this decision was based upon an informal poll of experts and users of the DNV Code). All stress calculations are made using the corroded wall thickness. Operating, Sustained, or Occasional load cases are treated identically (there is no provision for a code check for an Expansion load case, so no Expansion cases are generated under this code). For these load cases, three stress calculations are done, with different allowables. The stress calculation causing the highest percent of allowable is reported in the stress report, along with its specific allowable. These stress checks are: Hoop Stress: Sh

ns SMYS

Hoop Stress: Sh

nu SMTS n SMYS

Longitudinal Stress: SL Equivalent Stress: Se

n SMYS

Where: Sh = (Pi – Pe) (D – t) / 2t Pi = internal pressure Pe = external pressure D = outer diameter t = wall thickness ns = hoop stress yielding usage factor (see Tables C1 and C2 of the DNV Code) SMYS = specified minimum yield strength, at operating temperature nu = hoop stress bursting usage factor (see Tables C1 and C2 of the DNV Code) SMTS = specified minimum tensile strength, at operating temperature SL = maximum longitudinal stress n = equivalent stress usage factor (see Table C4 of the DNV Code) Se = [Sh2 + SL2 - ShSL + 3t2]1/2 t = torsional stress DNV does not make mention of reducers for SIF calculations.

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Local Coordinates Many analytical models in engineering are based upon being able to define a real physical object mathematically. This is accomplished by mapping the dimensions of the physical object into a similar mathematical space. Mathematical space is usually assumed to be either two-dimensional or threedimensional. For piping analysis, the three dimensional space is necessary, since almost all piping systems are three dimensional in nature. Two typical three-dimensional mathematical systems are shown below in Figure 1. Both of these systems are “Cartesian Coordinate Systems”. Each axis in these systems is perpendicular to all other axes.

Figure 1 – Typical Cartesian Coordinate Systems

In addition, for these Cartesian coordinate systems, the “right hand rule” is used to define positive rotation about each axis, and the relationship, or ordering, between the axes. Before illustrating the “right hand rule”, there are several traits of the systems in Figure 1 that should be noted. Each axis can be thought of as a “number line”, where the “zero point” is the point where all of the axes intersect. While only the positive side of each axis is shown in Figure 1, each axis has a negative side as well. The direction of the “arrow heads” indicates the “positive” direction of each axis. In Figure 1, the “X” axis has one arrowhead, the “Y” axis has two arrowheads, and the “Z” axis has three arrowheads. The circular arcs labeled “RX”, “RY”, and “RZ” define the direction of “positive” rotation about each axis. (This point will be discussed later.) Any point in space can be mapped to these coordinate systems by using its position along the number lines. For example, a point 5 units down the “X” axis would have a coordinate of (5.0, 0.0, 0.0). A point 5 units down the “X” axis and 6 units down the “Y” axis would have a coordinate of (5.0, 6.0, 0.0).

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CAESAR II Technical Reference Manual Notice that if the system on the right side of Figure 1 is rotated a positive 90 degrees about the “X” axis, the result is the system on the left side of Figure 1. The coordinate system on the left side of Figure 1 is the default CAESAR II global coordinate system. In this system, the “X” and “Z” axes define the horizontal plane, and the “Y” axis is vertical. (The other coordinate system in Figure 1 can be obtained in CAESAR II by selecting the “Z-axis Vertical” option, discussed later in this chapter.) All further discussion in this chapter will target this default coordinate system, unless otherwise noted.

Other Global Coordinate Systems There are other types of coordinate systems that can be used to mathematically map a physical object. A “Polar” coordinate system maps points (in a two dimensional space) using a radius and a rotation angle, (r, theta). A “Cylindrical” coordinate system maps points using a radius, a rotation angle, and an elevation, (r, theta, z). The origin in this system could be considered the center of the bottom of a cylinder. Cylindrical coordinates are convenient to use when there is an “axis” of symmetry in the model. A “Spherical” coordinate system maps points using a radius and two rotation angles, (r, theta, phi). The origin in this system could be considered the center of a sphere. Spherical coordinates are convenient to use when there is a “point” which is the center of symmetry in the model. Typically, none of these coordinate systems are easily used to map piping systems. Most piping software deals exclusively with the “Cartesian” coordinate system.

The Right Hand Rule In the “Cartesian” coordinate system, each axis has a positive and a negative side, as previously mentioned. Translations, straight-line movement, can be defined as movement along these axes. Rotation can also occur around these axes, as illustrated by the arcs in Figure 1. A standard rule must be applied in order to define the direction of positive rotation about these axes. This standard rule (known as the “right hand rule”) is: “Put the thumb of your right hand along the axis, in the positive direction of the axis. The direction your fingers curl is positive rotation about that axis.” This is best illustrated in Figure 2.

Figure 2 – The Right Hand Rule

The “right hand rule” can also be used to describe the relationship between the three axes. Mathematically, the relationship between the axes can be defined as: X cross Y = Z

EQ 1

Y cross Z = X

EQ 2

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Z cross X = Y

129

EQ 3

Where “cross” indicates the “vector cross product”. Physically, using your right hand, what do the above equations mean? This question is best answered by Figure 3.

Figure 3 – The Right Hand Rule - Continued

The left pane of Figure 3, corresponds to vector equation 3 above. Similarly, the center pane in Figure 3 also corresponds to vector equation 3 above. The right pane in Figure 3 corresponds to vector equation 2 above. All panes of Figure 3 refer to the left hand image of Figure 1. Straight-line movement along any axis can be therefore described as positive or negative, depending on the direction of motion. This straight-line movement accounts for three of the six degrees of freedom associated with a given node point in a model. (Analysis of a model requires the discretization of the model into a set of nodes and elements. Depending on the analysis and the element used, the associated nodes have certain degrees of freedom. For pipe stress analysis, using 3D Beam Elements, each node in the model has six degrees of freedom.) The other three degrees of freedom are the rotations about each of the axes. In accordance with the “right hand rule”, positive rotation about each axis is defined as shown in Figures 1 and 2. When modeling a system mathematically, there are two coordinate systems to deal with, a global (or model) coordinate system and a local (or elemental) coordinate system. The global or model coordinate system is fixed, and can be considered a constant characteristic of the analysis at hand. The local coordinate system is defined on an elemental basis. Each element defines its own local coordinate system. The orientation of these local systems varies with the orientation of the elements. Note: An important concept here (which will be reiterated later) is the fact that local coordinate systems are defined by, and therefore associated with, elements. Local coordinate systems are not defined for, or associated with, nodes.

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Pipe Stress Analysis Coordinate Systems As noted previously, most pipe stress analysis computer programs utilize the 3D Beam Element. This element can be described as an infinitely thin stick, spanning between two nodes. Each of these nodes has six degrees of freedom - three translations and three rotations. Piping systems (models) are constructed by defining a series of elements, connected by nodes. These pipe elements are typically defined as vectors, in terms of “delta dimensions” referenced to a global coordinate system. Several example pipe elements are shown below in Figure 4.

Figure 4 - Example Pipe Elements

For most pipe stress applications, there are two dominant global coordinate systems to choose from, either “Y” axis or “Z” axis up. These two systems are depicted in Figure 1. As previously noted, the global coordinate system is fixed. All nodal coordinates and element delta dimensions are referenced to this global coordinate system. For example, in Figure 4 above, the pipe element spanning from node 10 to node 20 is defined with a DX (delta X) dimension of 5 ft. Additionally, node 20 has a global “X” coordinate 5 ft. greater that the global “X” coordinate of node 10. Similar statements could be made about the other two elements in Figure 4, only these elements are aligned with the global “Y” and global “Z” axes. In CAESAR II, the user can choose between the two global coordinate systems shown in Figure 1. By default, the CAESAR II global coordinate system puts the global “Y” axis vertical, as shown in the left half of Figure 1, and in Figure 4. There are two ways to change the CAESAR II global coordinate system so that the global “Z” axis is vertical. The first method is to modify the configuration file in the current data directory. This can be accomplished from the Main Menu, by selecting TOOLS\CONFIGURE SETUP. Once the configuration dialog appears, select the Geometry tab, as shown in Figure 5. On this tab, check the Z Axis Up check box, as shown in the figure below.

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Figure 5 - Geometry Configuration

Once the Z Axis Vertical check box is activated, the CAESAR II global coordinate system will be in accordance with the right half of Figure 1. This configuration affects all new jobs created in this data directory. Existing jobs with the “Y” axis vertical are not affected by this configuration change. The second method to obtain a global coordinate system with the “Z” axis vertical is to switch coordinate systems from within the input for the specific job at hand. This can be accomplished from the Special Execution Parameters dialog of the piping input processor. This dialog is shown below in Figure 6.

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Figure 6 - Special Execution Parameters Dialog

Checking the Z Axis Vertical check box will immediately change the orientation of the global coordinate system axis, with corresponding updates to the element delta dimensions. However, the relative positions and lengths of the elements are not affected by this switch.

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Defining a Model Using the CAESAR II default coordinate system (Y axis vertical), and assuming the system shown below in Figure 7, the corresponding element definitions are given in Figure 8.

Figure 7 - Sample Piping Model

Figure 8 - Sample Piping Model Element Definitions

For this sample model, most of the element definitions are very simple: The first element, 10-20, is defined as 5 ft. in the positive global “X” direction. This element starts at the model origin. The second element, 20-30, is defined as 5 ft. in the positive global “Y” direction. This element begins at the end of the first element, since both elements share node 20. The third element, 30-40, is defined as 5 ft. in the negative global “Z” direction. Note in Figure 8 that the delta dimension for this element is a negative number. This is necessary to define the element in a negative direction. The fourth element, 40-50, runs in both the positive global “X” and negative global “Y” directions, this element slopes to the right and down. This element is defined with delta dimensions in both the DX and DY fields. Notice that these delta dimensions are equal in magnitude; therefore this element slopes at 45 degrees.

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CAESAR II Technical Reference Manual Continuing the model, from node 50, along the same 45 degree slope can be rather tedious, since most often only the overall element length is know, not its components in the global directions. In CAESAR II this can be best accomplished by activating the Direction Cosine dialog box, shown below in Figure 9. The Direction Cosine dialog can be activated by clicking the Browse button next to the DY field. Using this dialog box, the element length can be entered, and CAESAR II will determine the appropriate components in the global directions, based on the current direction cosines (which default to those of the preceding element).

Figure 9 - Direction Cosine Dialog

CAESAR II provides an additional coding tool, for longer runs of pipe with uniform node spacing. An “element break” option is provided, which allows an element to be broken into equal length segments, given a node number increment. In the preceding example, the model is defined solely using “delta dimensions”. By constructing the model in this fashion, it is assumed that the world coordinates of node 10 (the first node in the model) are at (0., 0., 0.). This assumption is acceptable in all but a one instance, when environmental loads are applied to the model. In this instance, the elevation of the model is critical to the determination of the environmental loads, and therefore must be specified. In CAESAR II, the specification of the starting node of the model can be accomplished using the [Alt+G] key combination, and all nodal coordinates will be displayed as “absolute” coordinates. Regardless of whether or not the global coordinates of the starting node are specified, the model relative geometry will plot the same. Once a model has been defined, there are a number of operations that can be performed on the entire system, or on any section of the system. These operations include: Translating the model: translation can be accomplished by specifying the global coordinates of the starting node of the model. If the model consists of disconnected segments, CAESAR II requests the coordinates of the starting node of each segment. Rotating the model: rotation can be accomplished by using the [LIST] processor or by clicking the button. The [LIST] processor presents the model in a spreadsheet, or grid, format, as shown in Figure 8. Options in this processor allow the model (or any sub-section of the model) to be rotated about any of the three global axes, a specified amount. For example, if the model shown in Figures 7 and 8 is rotated a (negative) -90 degrees about the global “Y” axis, the result is as shown in Figure 10.

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Figure 10 - Example of Model Rotation

Duplicating the model: duplication can also be accomplished by using the [LIST] processor. The entire model, or any sub-section of the model, can be duplicated.

Using Local Coordinates When analyzing a piping system, there are a number of items that must be checked and verified. These items include: Operating loads on restraints and terminal points

Maximum operating displacements

Hanger design results

Code stresses for code cases

Equipment Evaluations

Vessel Nozzle Evaluation

Expansion joint evaluation

Restraint loads and displacements are checked in the global coordinate system. This is necessary because restraint loads and displacements are nodal quantities. Element loads and stresses are most often evaluated in their local coordinate system. A good example illustrating the use of a local (element) coordinate system is the free body diagram, of forces and moments. The forces and moments in this free body diagram remain the same, regardless of the position of the element in the global coordinate system. Note however, that each element has its own local coordinate system. Furthermore, the local coordinate system of one element may be different from the local coordinate system of a different element. While the global coordinate system is typically referred to using the capital letters ‘X”, “Y”, and “Z”, local coordinate systems use a variety of nomenclature. In almost all cases, local coordinate systems use lower case letters. Typical local coordinate system axes are: “xyz”, “abc”, and “uvw”. CAESAR II uses “xyz” to denote the local element coordinate system. The local coordinate system for an element is related to the global coordinate system through a rule. There may be a number of such rules, depending on the type of element. In CAESAR II, the following rules are used to define the local coordinate systems of the piping elements in a model.

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CAESAR II Local Coordinate Definitions Rule 1 - Straight Pipe: For straight pipe elements, the local “x” axis always points from the “From Node” to the “To Node”. The local “y” axis can be found by the vector cross product of the local “x” axis with the global “Y” axis. Applying the “right hand rule”, this local “y” axis can be found by performing the following steps: 1

Lay your right hand on the pipe, with the wrist at the “From Node”, and the fingers pointing to the “To Node”.

2

Align or rotate your hand so that the global “Y” axis points perpendicularly out from the palm. The thumb is now aligned with the local “y” axis for this element.

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The local “z” axis can be found by the vector cross product of the local “x” and local “y” axes. An exception to this rule is the case of a vertical element. In this case, the local “x” axis is still aligned in the “From - To” direction. However, you can’t “cross” a vertical element into global “Y”, so the local “y” axis was arbitrarily assigned to align with the global “X” axis. The straight elements of the model in Figure 7 are reproduced below in Figure 11, along with their local coordinate systems. Notice that each of these straight elements has its own local coordinate system, and that in this model, they are all aligned differently.

Figure 11 - Local Coordinate Systems for Straight Elements (1)

In Figure 11, the positive direction of the local “x” axis for each element is defined according to the “From - To” definition of the element. For example, the local “x” axis of element 10-20 is aligned with the positive global “X” axis, because that is the direction defined in moving from node 10 to node 20. The local “x” axis of element 30-40 is aligned with the negative global “Z” axis, because that is the direction defined in moving from node 30 to node 40. Figure 11 should be studied to ensure a good understanding of how the local element coordinate system can be defined based on the definition of the element, especially with regard to the skewed element 40-50. As an additional example, the local element coordinate systems for the rotated system of Figure 10 are shown below in Figure 12.

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Figure 12 - Local Coordinate Systems for Straight Elements (2)

Rule 2 - Bend Elements: For the “near weld line” of bend elements, the local “x” axis is directed along the incoming tangent, in the “From – To” direction. The local “z” axis points to the center of the circle described by the bend. For the “far weld line” of bend elements, the local “x” axis is directed along the outgoing tangent, in the “From – To” direction. The local “z” axis points to the center of the circle described by the bend. In both cases, the local “y” axis can be found by applying the “right hand rule”. The local coordinate system for the bends in the example model of Figure 7 are shown below in Figure 13.

Figure 13 – Local Coordinate Systems for Bend Elements

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Rule 3 - Tee Elements: For tees, there is no element or “fitting” as there is in a CAD application. Rather designating a node as a tee simply applies code defined SIFs at that point, for the three elements framing into the tee node. As usual, the local “x” axis is defined by the element “From - To” direction. The local “y” axis coincides with the line that defines the “in-plane” plane of the tee (in other words, the local “y” axis is perpendicular to the plane of the three tee elements). The positive direction of the local “y” axis is found by (vectorally) crossing the local “x” axis of the header element with the local “x” axis of the branch, and then (strangely enough) reversing the sign (direction). (In those cases where the two header elements have opposite local “x” axes, CAESAR II chooses the first one that it finds.) The local “z” axis can then be determined using the right-hand rule. Note that the local “z” axis coincides with the “out-of-plane” axis of the tee, for each element. Examples of local coordinates for elements framing into tees are depicted below in Figure 14.

Figure 14 - Local Coordinate Systems for Tee Elements

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Applications - Utilizing Global and Local Coordinates Global coordinates are used most often when dealing with piping models. Global coordinates are used to define the model and review nodal results. Even though element stresses are defined in terms of axial and bending directions, which are “local coordinate system terms”, local coordinates are rarely used. A typical piping analysis scenario is as follows. A decision is made as to how the global coordinate system for the piping model will align with the plant coordinate system. Usually, one of the two horizontal axes is selected to correspond to the “North” direction. However, if this results in a majority of the system being skewed with respect to the global axes, one should consider realigning the model. It is best to have most of the system aligned with one of the global coordinate axes. The piping system is then assigned node points at locations where: there is a change in direction, a support, a terminal point, a point of cross section change, a point of load application, or any other point of interest. Once the nodes have been assigned the piping model can be defined using the “delta dimensions” as dictated by the orientation of the global coordinate system. Analysts should take advantage of the tools provided by CAESAR II in constructing the model - this includes the element Break option, the LIST, Rotate and Duplicate options, and the Direction Cosine facility. After verifying the input, confirming the load cases, and analyzing the model, output review commences. Output review involves checking various output reports to ensure the system responds within certain limits. These checks include: Checking that operating displacements make sense and are within any operational limits (to avoid ponding etc.). Displacements being “nodal quantities”, are reviewed in the global coordinate system. There is no local coordinate system associated with nodes. For the model defined in Figures 7 and 8, the operating displacements are shown in Figure 15 below.

Figure 15 - Operating Displacements

This report shows the movements of all of the nodes in the model, in each of the six degrees of freedom, in the global coordinate system.

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Checking that the restraint loads for the “structural load cases” are reasonable. This includes ensuring that the restraints can be designed to carry the computed load. Restraints being “nodal quantities”, are reviewed in the global coordinate system. There is no local coordinate system associated with restraints. For the model defined in Figures 7 and 8, the operating / sustained restraint summary is shown in Figure 16 below.

Figure 16 - Operating / Sustained Restraint Summary

This report shows the loads on the anchor at 10 and the nozzle at 50, for all six degrees of freedom, for the two selected structural load cases, in the global coordinate system. Checking the “Code cases” for codes stress compliance. Typically the “code stress” is compared to the “allowable stress” for each node on each element. Occasionally, when there is an overstress condition, a review of axial, bending, and torsion stresses are necessary. These stresses (axial, bending, and torsion) are “local coordinate system terms”, and therefore relate to the element’s local coordinate system. For the model defined in Figures 7 and 8, a portion of the sustained stress report is shown in Figure 17 below.

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Figure 17 - Sustained Stress Report

These reports provide sufficient information to evaluate the pipe elements in the model, to ensure proper behavior and code compliance. However, the analyst’s job is not complete, loads and stress must still be evaluated at terminal points, where the piping system connects to equipment or vessel nozzles. Depending on the type of equipment or nozzle, various procedures and codes are applied. These include API-610 for pumps and WRC-107 for vessel nozzles, as well as others. In the case of API-610 and WRC-107, a local coordinate system specific to these codes is employed. These local coordinate systems are defined in terms of the pump or nozzle/vessel geometry. When the equipment coordinate system aligns with the global coordinate system of the piping model, the nozzle loads from the restraint report (node 50 in Figure 14) can be used in the nozzle evaluation. However, when the equipment nozzle is skewed (as it is in the case of node 50 in Figure 14), the application of the loads is more difficult. In this case, it is best to use the loads from the element’s force/moment report, in local coordinates. The only thing to remember here is to flip the signs on all of the forces and moments, since the element force/moment report shows the loads on the pipe element, not on the nozzle. For the element from node 40 to node 50, the local element force/moment report is shown in Figure 18 below.

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Figure 18 - Local Element Force/Moment Report

Because the correlation between the pipe model’s coordinate systems and those of equipment codes (API, WRC, etc.) are often times tedious and error prone, CAESAR II provides an option in its equipment modules to acquire the loads on the nozzle directly from the static output. The user simply has to select the node and the load case; CAESAR II will acquire the loads and rotate them into the proper coordinate system as defined by the applicable equipment code. The user really does not have to be concerned with the transformation from global to local coordinates, even for skewed components. This is illustrated below, in Figure 19. In this figure, the API-610 nozzle loads at node 50 have been acquired by clicking the Get Loads from Output File button. Notice that the loads shown in Figure 19 are in the CAESAR II global coordinate system. This can be easily verified by comparing these values to those in the restraint summary (for the Operating load case) as shown previously in Figure 16.

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Figure 19 - API-610 Nozzle Load Acquisition

In the corresponding output report for this API-610 analysis, both the global and API local loads are reported. This is shown below in Figure 20.

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Figure 20 - API-610 Nozzle Output Report Segments

Notice in Figure 20, that each report segment indicates which values are related to the global coordinate system and which are related to the local API coordinate system.

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Transforming from Global to Local Converting (or transforming) values from the CAESAR II global coordinate system to a local coordinate system involves applying a number of rotation matrices to the global values. Matrix mathematics is not a trivial task, and one must exercise the utmost care to arrive at the correct result. For those that want to undertake this task themselves, a small utility (discussed in the July 2001 issue of COADE’s Mechanical Engineering News) can be downloaded from the COADE web site to perform this transformation. The use of this utility (GlbtoLocal) is illustrated here, using the nozzle at node 50 as an example. The element 40-50 is defined with the delta coordinates of: DX = 3 ft.

6.426 in

DY = -3 ft.

6.426 in

DZ = 0.0 The global restraint forces at node 50, in global coordinates, for the operating case are: FX = 323.

MX = -953.

FY = 4. MY = -9. FZ = -271.

MZ = -548.

Using this data as input to GlbtoLocal, the utility yields the forces on the restraint in the element’s local coordinate system. This is shown in Figure 21 below.

Figure 21 - Example Global to Local Transformation

The set of values labeled “Rotated Displacements / Load Vector” can be compared with the “Local Element Force / Moment” report, as shown in Figure 18. Note however, that a change in sign is necessary, since the restraint report shows loads acting on the restraint, while the element report shows loads acting on the element.

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Frequently Asked Questions What are global coordinates? Global coordinates defines the mapping of a physical system into a mathematical system. For any given model, the global coordinate system is fixed for the entire model. In CAESAR II, there are tow alternative global coordinate systems that can be applied to a model. Both coordinate systems follow the "right hand rule" and use "X", "Y", and "Z" as mutually perpendicular axes. The first uses the "Y" axis vertical, while the second uses the "Z" axis as vertical. What are local coordinates? Local coordinates represent the mapping for a single element. Local coordinate systems are used to define positive and negative directions and loads on elements. Local coordinate systems are aligned with the elements, and therefore vary throughout the model. What coordinates are used to plot and view the model? The model's global coordinate system is used to generate plots of the model. This is necessary since each element has its own local coordinate system, and these local systems can vary from element to element. Local coordinate systems are an element property, not a system property. How do you obtain restraint loads in local coordinates? In general, you don't - this doesn't make any sense. Restraint loads are a nodal property. Nodes don't have local coordinate systems, elements do. While an argument can be made that the local coordinate system of the connecting element should be used, this is only valid if one single element frames into the restraint.As soon as multiple elements frame into the restraint, there are multiple local coordinate systems to deal with. The lone exception is when a single element frames into a nozzle. In this instance, the restraint loads in this single element's coordinate system can be obtained from the element's local force/moment report, with a change in sign. How do you obtain nodal displacements in local coordinates? In general, you don't - this doesn't make any sense. Displacements are a nodal property. Nodes don't have local coordinate systems, elements do. Refer to the preceding discussion on restraint loads for additional details. What do you do with local coordinates? In most instances nothing. The only time local coordinates are useful in CAESAR II is when dealing with a skewed nozzle. The CAESAR II software interface makes the use of local coordinates unnecessary except in this one instance.

1

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Miscellaneous Processors In This Chapter Accounting ..................................................................................2 Batch Stream Processing .............................................................9 CAESAR II Fatal Error Processing.............................................11

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Accounting The CAESAR II accounting system has the following characteristics: Its use is optional. Users not wishing to keep accounting records of their runs never need to know that an accounting capability exists. Users conveniently controls all pricing factors. The total price of any job is computed from: IF (C4 > 0.0) THEN cost = C1*cputime + (C2*nodes + C3*elements) * C4 * numcases + C5 ELSE cost = C1*cputime + (C2*nodes + C3*elements) + C5 ENDIF Users enters C1, C2, C3, C4, and C5 one time, and changes them only when needed. Any of the constants may be zero but at least one must be greater than zero. Accounting reports are generated on a per run basis and are summarized on a per account basis. Reports may be generated for any user requested combination of account numbers. Account numbers are user-defined and may be up to 25 alphanumeric characters. Account and program access can be controlled through the accounting system via optional password protection. Account numbers can be identified for each job using either of two methods: Account number must be selected from a displayed table of allowed account numbers, or will default to the last valid account number input. The account number table is set up and maintained by the account manager. Account number must be some non-blank string. There is no default, and the user’s entry must match one of the allowed account numbers input previously by the account manager. Access to the available account number list is password protected. Users not having valid account numbers will not be permitted to run. Generated reports contain: Account number Jobname Time and Date of Run Number of Nodes, Elements, and Load Cases Calculated Job Cost

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3

Accounting summary reports include subtotals on a per account number basis, the number of jobs run under the account, and the time period the account has been active. The accounting system is delivered in an uninitialized state. To use the accounting system, users must change this state to active. (It may later be deactivated if the user does not want to use the account recordkeeping feature.) To activate the accounting system from the CAESAR II Main Menu, select TOOLS ACCOUNTING. The Accounting dialog displays.

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CAESAR II Technical Reference Manual

Select the applicable accounting method (either type 1 or type 2) and then click the Activate Accounting button. The user will receive a that it is indeed activating the accounting as requested. Next set the Pricing Factors by selecting the next tab in the window to show the sheet as displayed below.

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5

Users should enter any costs as appropriate; blanks are allowed. Each rate is multiplied by the respective job quantity, and the sum of these products is equivalent to the job cost. Job costs are calculated on an integer dollar basis, and will never be less than one dollar. Any of the 5 rate constants can be zero, but not all; and none of the constants may be negative. Account numbers are entered under the Account Numbers tab as shown below. These are the numbers that will be used to prompt users for an account number during program execution. Be sure to click the Save button before exiting!

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CAESAR II Technical Reference Manual

Once the accounting system is initialized and the pricing factors are set, users can return to the CAESAR II Main Menu and initiate jobs with account tracking. The prompt for the account number will appear during analysis, immediately after the user starts a CAESAR II execution. If type 2 accounting is implemented then users must match the appropriate account number exactly, whereas all account numbers will be displayed in a list box if type 1 accounting has been activated.

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7

The prompt for accounting information requires user-account identification. For type 2 accounting the user is expected to type in a valid account number, or click OK for the default (last used) account number. For type 1 accounting users simply select the appropriate account number from the list and click OK to continue. An example Accounting report displays below:

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CAESAR II Technical Reference Manual

Accounting File Structure The format of the CAESAR II accounting file is structured so that users may write a program to access and/or manipulate this file. The name of the CAESAR II accounting file is ACCTG.DAT. This file contains all of the information used by CAESAR II to produce accounting reports. The accounting file may be opened (in FORTRAN) with the following: OPEN(1,FILE=’ACCTG.DAT’,STATUS=’OLD’,FORM=’BINARY’, ACCESS=’DIRECT’,RECL=55)

The following information is stored on each record: Variable

Type

Definition

JOBNAME

CHARACTER*8

Name of the job being run.

ICPUTIME

INTEGER*4

Analysis CPU time used (Seconds)

NODES

INTEGER*2

Number of nodes in the job

NELEMS

INTEGER*2

Number of elements in the job

NLOADS

INTEGER*2

Number of load cases in the job

MYEAR

INTEGER*2

Year the job was run

MMONTH

INTEGER*2

Month the job was run

MDAY

INTEGER*2

Day of the month the job was run

MHOUR

INTEGER*2

Hour of the day the job was run

MMINUTE

INTEGER*2

Minutes of the hour when the job was run

MSECOND

INTEGER*2

Seconds of the minute when the job was run

ACCOUNTNO

CHARACTER*25

Account number to be billed for job

The first record contains only a single integer value (ILAST) giving the last valid record number in the accounting file. The number of job entries is equal to (ILAST-1). This first record may be read: READ(1,REC=1) ILAST

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Batch Stream Processing The Batch Stream Processor is a module which allows users to analyze multiple jobs, in batch mode. This enables users to instruct the computer to run up to twelve different jobs completely unattended. The following are the requirements to properly initiate a batch stream process: The jobs must all be located in the same data directory, and the Default Data Directory must be set to this directory. The jobs must be ready to run. This means that the jobs must have successfully passed error checking and static and dynamic load cases have been defined. If the static load cases have not been defined, CAESAR II uses the standard recommended cases. Accounting should be turned off, or set so that a default account number can be assumed by the program. Adequate disk space must be available to generate the scratch and output files for all of the jobs. Users can enable the Batch Stream Processor from the CAESAR II MAIN MENU by clicking TOOLS MULTI- JOB ANALYSIS.

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CAESAR II Technical Reference Manual

The Define Jobs to Run button enables users to define the names and job types to be executed in the stream. The job names are the usual CAESAR II job names that the user has prepared for analysis. The job name specification screen is shown in the following figure.

Once the job names (up to forty) have been specified, click the OK button. The Batch Stream window returns. Clicking the Analyze Specified Jobs button will start the analysis of all previously defined jobs. The user does not have to analyze the jobs immediately. The job names and analysis types are stored in a data file, BATCH.STM, which can be invoked at any time by the user. When the user is ready, the Batch Stream Processor can be started and the “analyze” option invoked. The user can then leave the computer, and return to review the output at a later time. The Batch Stream Processor creates a “log” file of its progress so that users have an idea of how long the process took, or can diagnose any failures in the batch process. This log file is named “BATCH.LOG” and can be found in the directory with the jobs. This file is a standard ASCII text file which can be edited or printed.

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CAESAR II Fatal Error Processing Every effort has been made to alert the user that data may be inconsistent or unusual for the type of analysis being attempted. However, there exists the potential for user modeling techniques or hardware/operating system problems to generate an error condition within the CAESAR II computation routines. Recognizing this potential, internal self checks are performed by CAESAR II to trap these abnormal conditions. (Examples of abnormal conditions are: full hard disks, invalid or expired ESLs, file corruption, insufficient free memory, etc.) Whenever a fatal error condition arises, CAESAR II will abort the current process. However, CAESAR II attempts to provide the user with an explanation of what went wrong to cause the process to be aborted. This is accomplished in several stages as outlined in the following discussion. First, each error trap/condition is assigned a unique number. When an abort condition occurs, this error number and a short description of the error are displayed in a window. An example of such a message is given in the next figure.

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CAESAR II Technical Reference Manual

When the OK button is clicked the error text window is closed and the user has the option of referencing further error information. (This may be desirable when one error definition references another.) The OK button from the additional error information window returns program control to the main CAESAR II Main Menu. This additional error information may be called upon at any time from the CAESAR II Main Menu by selecting the DIAGNOSTICS-ERROR REVIEW menu option.

1

CHAPTER 8

Interfaces In This Chapter Overview of CAESAR II Interfaces ............................................2 CAD Interfaces............................................................................4 Generic Neutral Files ..................................................................74 Computational Interfaces.............................................................95 Data Export to ODBC Compliant Databases ..............................102

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CAESAR II Technical Reference Manual

Overview of CAESAR II Interfaces There are several external interfaces in existence which allow data transfer between CAESAR II and other software packages. These interfaces can be accessed via the Tools menu item on the CAESAR II Main Menu. Choosing the External Interface menu item exposes an additional menu shown below from which many interface packages are available.

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3

These interfaces are the means through which CAESAR II data is accepted from other sources, or data generated in CAESAR II is provided to other packages. For the most part, this data transfer is from a drawing or analysis package to CAESAR II. The CAESAR II Neutral File transfers both to and from CAESAR II, and the AUTOCAD interface only transfers CAD data from CAESAR II. Note CADWorx/PIPE provides a seamless, bi-directional interface between AutoCAD and CAESAR II, but does not have to go through a translation procedure. 1

Most of the interfaces are CAD interfaces. The exceptions are: LIQT, PIPENET, the C2DAT Matrix, and the CAESAR II Neutral File.

2

The CAD interfaces are intended to transfer the piping geometry into CAESAR II. The resulting CAESAR II input must be thoroughly checked, with loads, restraints, and other specifics added.

3

The interface labeled “CAESAR II Neutral File” is the only interface (aside from CADWorx/PIPE) that is capable of transferring 100% of the data which comprises the _A (input) file.

4

PRO-ISO, CADPIPE, and AutoPlant are not stand-alone CAD packages. Instead, these are intelligent symbols libraries for use with AutoCAD. The interface out to AutoCAD does not utilize any of these three packages; it just creates a DXF file.

5

LIQT is a transient analysis package for liquids in piping networks, and can calculate pressure imbalances as a function of time. This LIQT output is converted by the CAESAR II interface to create force response spectra for CAESAR II dynamic input.

6

PIPENET is a transient analysis package for liquids in piping networks, and can calculate pressure imbalances as a function of time. This PIPENET output is converted by the CAESAR II interface to create a CAESAR II dynamic input file for a force response spectrum analysis.

7

The interfaces typically prompt the user for a file name, transfer the data, and then prompt for another file name. This circular procedure is continued until a blank file name is encountered or the user presses the Cancel button.

8

Users and third party developers beginning an interface to CAESAR II are urged to follow the requirements of the CAESAR II Neutral File interface, since this will enable all of the spreadsheet data to be transferred.

9

CADWorx/PIPE is COADE's piping design and drafting program for the AutoCAD environment. Data may be completely and seemlessly transferred between CAESAR II and CADWorx/PIPE, without creating any neutral files or going through any intermediate steps.

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CAESAR II Technical Reference Manual

CAD Interfaces CADWorx/PIPE Link CADWorx is an AutoCAD based design/drafting program (developed by COADE) with a bi-directional data transfer link to CAESAR II. CADWorx allows models to be created in ortho, iso, 2D, or 3D modes. Models constructed in CADWorx can be sent into CAESAR II, and models built in CAESAR II can be sent into CADWorx. Modifications made in either program are retained for future transfers. In addition, CADWorx allows CAESAR II output data to be imported and placed on the drawing. This provides the ability to generate stress and restraint isometrics. Since the interface operates seemlessly, no action need be taken on the CAESAR II side—CADWorx/PIPE simply uses CAESAR II _A (input) and _P (output) files—so the CADWORX/PIPE option on this menu serves only as a reminder. For more information on importing and exporting CAESAR II files to and from CADWorx/PIPE, refer to that product's User Manual.

DXF AutoCAD Interface Once a job has successfully passed error checking, its geometric information can be converted into an AutoCAD DXF file using the CAESAR II External Interface Module. The job must pass the error checker, since several of the execution files created by the error checker are used. To generate an AutoCAD DXF file simply choose the AUTOCAD DXF FILE menu item, enter the name of the job to be converted into a DXF file when prompted, and click OK on the dialog box. When the file conversion is complete, the program will prompt for another job name. This cycle will be repeated until the Cancel button is clicked. Next, the user should copy all of the just created DXF files into the AutoCAD subdirectory. Start AutoCAD as normal, begin a new drawing, and enter a drawing name. The BEGIN NEW DRAWING option must be selected. At the first prompt, issue the DXFIN command. This will cause AutoCAD to prompt for the file tp read. When reading the specified file, AutoCAD will rescale and display the model. To access the COADE supplied LISP routines, which scale node numbers, a LISP file must be loaded. The command to accomplish this is (load "NODISZ"). Note: The parentheses in the previous command are required. Information about pipes and node points can be obtained by using the LIST command. The ATTDISP command can be used to turn on/off the attribute display, which at this point consists of only node numbers. the size of the node numbers can be changed by using the LISP routine NODISZ. To resize the node numbers, simply enter NODISZ, and answer the prompts. To resize the node numbers, simply enter NODISZ and answer the prompts. In order for this interface program to function properly, all of the intermediate data files, generated by the CAESAR II error checker, must be present. This is the only problem that has ever terminated this interface program.

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CADPIPE Interface The interface between CAESAR II and CADPIPE is a one-way transfer of the geometry data from CADPIPE to CAESAR II. The geometry data consists of the pipe lengths, diameters, thicknesses, connectivities, and node numbers. All nodal specific quantities (restraints, loads, displacements, etc.) must be added to the CAESAR II input file in the usual manner by the user. The CADPIPE interface is set up so that several models can be transferred in a single session. The first prompt is for the name of the CADPIPE connectivity (.UDE ) neutral file. Once the user specifies this file name, the transfer process occurs and the interface program prompts for another neutral file name. This is an endless cycle until the user terminates with the Cancel button. The neutral file read by the interface program must be generated by the CADPIPE program. Details of this step can be found in the CADPIPE documentation. The CADPIPE neutral file must be transferred into the CAESAR II directory so that it is available to the interface program. The interface program reads the CADPIPE neutral file and generates the CAESAR II input file and a log file of the transfer process. Users should check the data in both the CAESAR II input file and the log file for consistency and any assumptions made by the interface. The following paragraphs describe the layout of the data extracted from the CADPIPE neutral file and how it is arranged for storage in this interface program. The data storage is maintained in two arrays, the first contains geometry data for each pipe element, the second array contains additional loading and specification data. In the first array, an entry is required for each piece of pipe in the system. A “pipe” in this sense is an entity between two nodes, which could be a pipe, or a rigid element. There are 12 values per entry, where all values must be specified. Field 1 - ELMT This is the pipe element number, which may correspond to an entry in the second array. This is also the pipe/element number in the model. These values should be sequential from 1. Field 2 - N1 This is the “FROM” node number, i.e. the starting node for the element. These values must be greater than zero and less than 32000. Field 3 - N2 This is the “TO” node number, i.e. the ending node for the element. These values must be greater than zero and less than 32000. Field 4 - DX This is the “delta X” dimension for the element. This is the distance between N1 and N2 in the “X” direction. Field 5 - DY This is the “delta Y” dimension for the element. This is the distance between N1 and N2 in the “Y” direction. In CAESAR II, “Y” is vertical. Field 6 - DZ

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CAESAR II Technical Reference Manual

This is the “delta Z” dimension for the element. This is the distance between N1 and N2 in the “Z” direction. Field 7 - DIAM This is the pipe outer diameter. Field 8 - THK This is the pipe wall thickness. Field 9 - ANCH This is a restraint (support) indicator flag. If ANCH is 1, then there is a restraint on N1. If ANCH is 2, then there is a restraint on N2. The type of restraint can be obtained from the second array. Field 10 - BND This field indicates the presence of a bend at the N2 end of the element. If BND is 1, there is a bend at N2. If BND is 0, this is a straight pipe. Field 11 - BRAD This field is used to specify the bend radius if the bend is not a long radius bend. The value here should be the desired bend radius. Field 12 - RIGD This field is a flag used to indicate that the current element is a rigid element. The weight of the element can be obtained from the second array. Records in the second array are only necessary when additional data is required. This means there will always be a record in first array for pipe element #1 (this could be the only entry in the array). Any additional entries will contain some type of change to data normally duplicated forward by CAESAR II. Field 1 - ELMT This is the pipe element number, which corresponds to an entry in the first array. This is also a pipe/element number in the model. These numbers are sequential from 1. Field 2 - TEMP1 This is the operating temperature for load case 1, found by scanning the CADPIPE data for the maximum temperature. Field 3 - PRESS1 This is the operating pressure for load case 1, found by scanning the CADPIPE data for the maximum pressure. Field 4 - RGDWGT This value is the weight of rigid elements. This entry is only required if the “RIGID” flag was set in the first array.

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Field 5 - TEEFLG This value indicates the “TEE” type. 1 - reinforced 2 - unreinforced 3 - welding tee 4 - sweepolet 5 - weldolet 6 - extruded welding tee Field 6 - RESTYP This value is the restraint (support) type indicator. Type values are: 0 - anchor 1 - double acting X 2 - double acting Y 3 - double acting Z 4 - double acting RX 5 - double acting RY 6 - double acting RZ Field 7 - RINFO1 Data for supports, by default, the restraint stiffness. Field 8 - RINFO2 Data for supports, by default, the restraint gap. Field 9 - RINFO3 Data for supports, by default, the restraint friction coefficient. Field 10 - MATID The CAESAR II material ID value. Note that if the coefficient of expansion is to be changed, it should be entered in the Temperature field above (Field 2). Field 11 - EMOD

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The value of Young’s modulus. Field 12 - POIS The value of Poisson’s ratio. Field 13 - GAMMA The weight density of the material. Field 14 - INSTHK The insulation thickness. Field 15 - INSWGT The weight density of the insulation material. Field 16 - FLDWGT The weight density of the pipe contents (fluid). Field 17 - TEENOD The element node number where there is a tee. Field 18 - (Placeholder for future development.) Field 19 - (Placeholder for future development.) Field 20 -(Placeholder for future development.)

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CADPIPE Example Transfer The following is an example connectivity file produced by the CADPIPE program. Examination of this file reveals two distinct regions. The first region defines the entities which make up the piping system, while the second region connects the entities. Both regions are required for the interface to work properly. The first line of each entity definition contains various codes which define: the element type, the element diameter, and the element thickness. BEGIN_ENTITY ENTITY_NUMBER 1 ATTRIBUTES 1CAESAR

AAA1

C-2OBB—1dLATL

INSERTION 1.80000000e+002 3.36000000e+002 1.20000000e+003 END 1.80000000e+002 3.36000000e+002 1.20000000e+003 END 1.80000000e+002 3.35999961e+002 1.20350000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 2 ATTRIBUTES 1CAESAR

AAA1

C-2OPP—ATLATL

134.50

INSERTION 1.80000000e+002 3.35999997e+002 1.27075000e+003 END 1.80000000e+002 3.35999961e+002 1.20350000e+003 END 1.80000000e+002 3.36000033e+002 1.33800000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 3 ATTRIBUTES 1CAESAR

AAA1

C-3O1B—ATLATL

INSERTION 1.80000000e+002 3.36000000e+002 1.34700000e+003 END 1.89000000e+002 3.36000000e+002 1.34700000e+003 END 1.80000000e+002 3.36000033e+002 1.33800000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 4

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CAESAR II Technical Reference Manual

ATTRIBUTES 1CAESAR

AAA1

C-0OPP—ATLATL

105.38

INSERTION 2.41687500e+002 3.35999959e+002 1.34700000e+003 END 1.89000000e+002 3.36000000e+002 1.34700000e+003 END 2.94375000e+002 3.35999917e+002 1.34700000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 5 ATTRIBUTES 1CAESAR

AAA1

C-0O2H—ATLATLATL

INSERTION 3.00000000e+002 3.36000000e+002 1.34700000e+003 END 3.05625000e+002 3.36000083e+002 1.34700000e+003 END 2.94375000e+002 3.35999917e+002 1.34700000e+003 END 3.00000083e+002 3.30375000e+002 1.34700000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 6 ATTRIBUTES 1CAESAR

AAA1

C-0O1B—ATLATL

INSERTION 4.02000000e+002 3.36000000e+002 1.34700000e+003 END 3.93000000e+002 3.35999934e+002 1.34700000e+003 END 4.01999934e+002 3.45000000e+002 1.34700000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 7 ATTRIBUTES 1CAESAR

AAA1

C-0OPP—ATLATL

90.00

INSERTION 4.02000017e+002 3.90000000e+002 1.34700000e+003 END 4.01999934e+002 3.45000000e+002 1.34700000e+003 END 4.02000099e+002 4.35000000e+002 1.34700000e+003 END_ENTITY

Chapter 8 Interfaces

BEGIN_ENTITY ENTITY_NUMBER 8 ATTRIBUTES 1CAESAR

AAA1

C-3O1B—ATLATL

INSERTION 4.02000000e+002 4.44000000e+002 1.34700000e+003 END 4.02000099e+002 4.35000000e+002 1.34700000e+003 END 4.02000033e+002 4.44000000e+002 1.33800000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 9 ATTRIBUTES 1CAESAR

AAA1

C-2OBB—1dLATL

INSERTION 4.02000000e+002 4.44000000e+002 1.20000000e+003 END 4.02000000e+002 4.44000000e+002 1.20000000e+003 END 4.02000000e+002 4.43999961e+002 1.20350000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 10 ATTRIBUTES 1CAESAR

AAA1

C-2OPP—ATLATL

134.50

INSERTION 4.02000017e+002 4.43999981e+002 1.27075000e+003 END 4.02000000e+002 4.43999961e+002 1.20350000e+003 END 4.02000033e+002 4.44000000e+002 1.33800000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 11 ATTRIBUTES 1CAESAR

AAA1

C-0O1B—ATLATL

INSERTION 3.00000000e+002 2.16000000e+002 1.34700000e+003 END 2.99999967e+002 2.25000000e+002 1.34700000e+003 END 3.09000000e+002 2.16000033e+002 1.34700000e+003

11

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CAESAR II Technical Reference Manual

END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 12 ATTRIBUTES 1CAESAR

AAA1

C-0OPP—ATLATL

105.38

INSERTION 3.00000025e+002 2.77687500e+002 1.34700000e+003 END 2.99999967e+002 2.25000000e+002 1.34700000e+003 END 3.00000083e+002 3.30375000e+002 1.34700000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 13 ATTRIBUTES 1CAESAR

AAA1

C-0OPP—ATLZTL

69.00

INSERTION 3.43500000e+002 2.16000017e+002 1.34700000e+003 END 3.09000000e+002 2.16000033e+002 1.34700000e+003 END 3.78000000e+002 2.16000000e+002 1.34700000e+003 END_ENTITY BEGIN_ENTITY ENTITY_NUMBER 14 ATTRIBUTES 1CAESAR

AAA1

C-0OPP—ATLATL

87.38

INSERTION 3.49312500e+002 3.36000008e+002 1.34700000e+003 END 3.05625000e+002 3.36000083e+002 1.34700000e+003 END 3.93000000e+002 3.35999934e+002 1.34700000e+003 END_ENTITY BEGIN_RUN LINE_NUMBER CAESAR

AAA1

BEGIN_COORD 1.80000000e+002 3.00000000e+002 1.20000000e+003 END_COORD

3.00000000e+002 3.36000000e+002 1.34700000e+003

BEGIN_SEGMENT

Chapter 8 Interfaces

BEGIN_COORD 1.80000000e+002 3.00000000e+002 1.20000000e+003 END_COORD

1.80000000e+002 3.36000000e+002 1.20000000e+003

ENTITY 1 END_SEGMENT BEGIN_SEGMENT BEGIN_COORD 1.80000000e+002 3.36000000e+002 1.20000000e+003 END_COORD

1.80000000e+002 3.36000000e+002 1.34700000e+003

ENTITY 1 ENTITY 2 ENTITY 3 END_SEGMENT BEGIN_SEGMENT BEGIN_COORD 1.80000000e+002 3.36000000e+002 1.34700000e+003 END_COORD

3.00000000e+002 3.36000000e+002 1.34700000e+003

ENTITY 3 ENTITY 4 ENTITY 5 END_SEGMENT END_RUN BEGIN_RUN LINE_NUMBER CAESAR

AAA1

BEGIN_COORD 3.00000000e+002 3.36000000e+002 1.34700000e+003 END_COORD

3.78000000e+002 2.16000000e+002 1.34700000e+003

BEGIN_SEGMENT BEGIN_COORD 3.00000000e+002 3.36000000e+002 1.34700000e+003 END_COORD ENTITY 5

3.00000000e+002 2.16000000e+002 1.34700000e+003

13

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ENTITY 12 ENTITY 11 END_SEGMENT BEGIN_SEGMENT BEGIN_COORD 3.00000000e+002 2.16000000e+002 1.34700000e+003 END_COORD

3.78000000e+002 2.16000000e+002 1.34700000e+003

ENTITY 11 ENTITY 13 END_SEGMENT END_RUN BEGIN_RUN LINE_NUMBER CAESAR

AAA1

BEGIN_COORD 3.00000000e+002 3.36000000e+002 1.34700000e+003 END_COORD

4.44000000e+002 4.44000000e+002 1.20000000e+003

BEGIN_SEGMENT BEGIN_COORD 3.00000000e+002 3.36000000e+002 1.34700000e+003 END_COORD

4.02000000e+002 3.36000000e+002 1.34700000e+003

ENTITY 5 ENTITY 14 ENTITY 6 END_SEGMENT BEGIN_SEGMENT BEGIN_COORD 4.02000000e+002 3.36000000e+002 1.34700000e+003 END_COORD ENTITY 6 ENTITY 7 ENTITY 8

4.02000000e+002 4.44000000e+002 1.34700000e+003

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END_SEGMENT BEGIN_SEGMENT BEGIN_COORD 4.02000000e+002 4.44000000e+002 1.34700000e+003 END_COORD

4.02000000e+002 4.44000000e+002 1.20000000e+003

ENTITY 8 ENTITY 10 ENTITY 9 END_SEGMENT BEGIN_SEGMENT BEGIN_COORD 4.02000000e+002 4.44000000e+002 1.20000000e+003 END_COORD

4.44000000e+002 4.44000000e+002 1.20000000e+003

ENTITY 9 END_SEGMENT END_RUN As the interface runs, status messages are displayed on the user’s terminal for informative purposes. Once the transfer is complete, the user should review the .LOG file generated to insure that there are no unexplained errors or warnings. The .LOG file generated for the above .UDE file is listed as follows.

*** CAESAR II / CADPIPE Geometry Translator *** CADPIPE data as read in for NEUTRAL file: NRGTST1.UDE

General Notes This file contains the status of the data conversion from the CADPIPE ISO system to the CAESAR II stress analysis package. The data contained in this file is grouped into three sections: 1

Entity information

2

Segment connectivity information

3

Final interpreted CAESAR II data.

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Anomalies with final CAESAR II model geometry should be traced through this file, possibly back to the CADPIPE connectivity file. Notes and warning messages are shown below as necessary. Since all required CAESAR II data is not available in the CADPIPE environment, CAESAR II must make certain modeling assumptions. Users are cautioned to verify the following assumptions: 1

Thicknesses of .05 are program generated because no match could be found in the standard CAESAR II diameter/thickness tables. This value must be corrected once in CAESAR II.

2

Rigid elements are assumed to have a weight of 1.0. This value should be corrected once in CAESAR II.

3

Temperatures, pressures, and other loading items are not available for transfer by the interface.

4

Restraint information is not available for transfer by the interface.

5

Material #1 (low carbon steel) is assumed by the interface program.

Error Code Definitions 1

The item code for this entity indicates that it is a custom bend. This interface will make the transfer assuming it is a long radius elbow. The correction to the proper radius must take place on the CAESAR II spreadsheet.

2

The item code for this entity indicates that it is a mitered bend. This interface will make the transfer assuming it is a long radius elbow. The correction to the proper radius and number of cuts must take place on the CAESAR II spreadsheet.

3

The item code for this entity indicates that it is some type of "OLET" fitting. Since there is only a single reference to this entity in the CADPIPE neutral file, this segment will be discontiguous with the rest of the model in CAESAR II. This interface will attempt to connect the "OLET" as it sees fit. The final geometry should be checked!

4

The item code for this entity is unknown to the current version of the interface. The entity will be set to a 2 node, zero length rigid element. The user must modify the CAESAR II data to correct this anomaly.

5

The segment being processed referenced and ENTITY that was not defined in the "ENTITY Information " section of the ".UDE" file. This indicates some type of error during the generation of the neutral file. Regenerate the neutral file before using the interface again.

Chapter 8 Interfaces

17

CADPIPE LOG File Discussion The .LOG file is very useful in locating problems which may have been encountered by the interface program. The .LOG file is broken down into the following sections: Introduction: A one page summary listing general notes about the interface and defines the error code. Section 1: Lists the entity information as read from the CADPIPE connectivity file. Note that each entity has been grouped into one of four possible element types, node numbers have been assigned, and the coordinate system has been rotated to conform to the standard pipe stress coordinate system (Y vertical). Section 2: Details the interpretation and model building process. Section 3: Lists the final transformed data which the interface program wrote as the CAESAR II input file. A sample .LOG file follows. ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Section 1-Entity Information Element types are: 1 - Pipe 2 - Bend 3 - Intersection 4 - Rigid Interpreted Entity information for: 14 Entities.

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CAESAR II Technical Reference Manual

Section 2-Segment Information Processing LINE_NUMBER: CAESAR Entity

AAA1 1 Original nodes:

10.

STARTING new segment with new Entity #

20.

1, “FROM” node is

10.

CAESAR II type is PIPE Final nodes:

10.

20.

Finished processing segment with entities: Entity

1 Original nodes:

1

10.

20.

STARTING new segment with old Entity # 1, “FROM” node is 20. CAESAR II type is 1. Entity 1 PIPE has already been processed. Skip in progress. Entity 2 Original nodes: Final nodes: Entity

20.

30.

40.

40.

3 Original nodes:

50.

60.

Switched TO/FROM orientation. Final nodes:

40.

50.

Finished processing segment with entities: Entity

3 Original nodes:

1

60.

STARTING new segment with old Entity #

2

3

50.

3, “FROM” node is

50.

CAESAR II type is 2. Entity

3 BEND has already been processed. Skip in progress.

Entity

4 Original nodes:

Final nodes: Entity

50.

5 Original nodes:

Resetting element deltas.

70.

80.

90.

100.

80.

4 “TO” node from

Finished processing segment with entities:

80. to 100. and adjusting 3

4

5

Chapter 8 Interfaces

Processing LINE_NUMBER: Entity

CAESAR

5 Original nodes:

AAA1

100.

100.

STARTING new segment with old Entity # 5, “FROM” node is 100. CAESAR II type is 3. Entity

5 TEE

has already been processed. Skip in progress.

Entity 12 Original nodes:

230.

240.

Switched TO/FROM orientation. Final nodes:

100.

230.

Entity 11 Original nodes: Final nodes:

230.

210.

220.

220.

Finished processing segment with entities: Entity 11 Original nodes:

210.

STARTING new segment with old Entity # CAESAR II type is

5

12

11

220. 11, “FROM” node is

220.

2.

Entity 11 BEND has already been processed. Skip in progress. Entity 13 Original nodes: Final nodes:

220.

250.

260.

260.

Finished processing segment with entities: Processing Entity

LINE_NUMBER:

CAESAR

5 Original nodes:

11

13

AAA1 100.

STARTING new segment with old Entity #

100. 5, “FROM” node is

100.

CAESAR II type is 3. Entity

5 TEE

has already been processed. Skip in progress.

Entity 14 Original nodes: Final nodes: Entity

100.

280.

280.

280.

6 Original nodes:

Final nodes:

270.

120.

110.

120.

19

20

CAESAR II Technical Reference Manual

Finished processing segment with entities: Entity

6 Original nodes:

110.

STARTING new segment with old Entity # CAESAR II type is

6 BEND

Entity

7 Original nodes:

Final nodes:

120. 6, “FROM” node is

140.

130.

140.

150.

160.

8 Original nodes:

150.

STARTING new segment with old Entity #

Entity

Skip in progress.

160.

Finished processing segment with entities:

Entity

120.

140.

8 Original nodes:

CAESAR II type is

6

has already been processed.

120.

Final nodes:

Entity

14

2.

Entity

Entity

5

6

7

8

160. 8, “FROM” node is

160.

2.

8 BEND

has already been processed.

10 Original nodes:

190.

200.

170.

180.

Skip in progress.

Switched TO/FROM orientation. Final nodes: Entity

160.

190.

9 Original nodes:

Switched TO/FROM orientation. Final nodes:

190.

170.

Finished processing segment with entities: Entity

9 Original nodes:

180.

STARTING new segment with old Entity # CAESAR II type is

1.

8

10

9

170. 9, “FROM” node is

170.

Chapter 8 Interfaces

Entity

9 PIPE

has already been processed.

Finished processing segment with entities:

9

21

Skip in progress.

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CAESAR II Technical Reference Manual

Section 3-Final CAESAR II Data *** C A E S A R I I INTERPRETED GEOMETRY DATA ***

*** C A E S A R I I INTERPRETED PROPERTY DATA *** Part 1

*** C A E S A R I I INTERPRETED PROPERTY DATA ***

Part 2

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Data transferred to CAESAR II array structures. The CAESAR II job file name is: NRGTST._A Starting generation of CAESAR II input file for: 13 Elements 4 Bends 0 Rigids 0 Restraints Conversion of data to CAESAR II completed.

Chapter 8 Interfaces

23

Checking the CADPIPE/CAESAR II Data Transfer It is very important that the resulting CAESAR II input file be verified by the user. The first step in the verification process is the review of the log file to see if any errors or warnings were generated. The .LOG file is a standard ASCII text file which can be printed on the system printer or scanned with a text editor. The second step is to enter the input mode of the CAESAR II program and plot the model. The CAESAR II plot for the CADPIPE example is shown in the following figure.

24

CAESAR II Technical Reference Manual

If the resulting CAESAR II geometry is inconsistent with the CADPIPE drawing, look for the problem in the .LOG file. First, identify the problem area and locate the relevant elements in Section 3 of the .LOG file. Next, find the appropriate segment in Section 2 of the .LOG file and ensure it contains the same entities as shown in the CADPIPE connectivity file. Finally, verify the information in Section 1 of the .LOG file matches the interpreted data in Section 3. Anomalies with the resulting CAESAR II geometry can usually be attributed to one of the following causes: Occasionally an unexpected geometry condition will be handed to the CAESAR II interface program. The solution to this problem is to update the interface program for the current condition. The user should forward the .UDE file to COADE for analysis and subsequent interface modification. An unknown item code was encountered. This indicates that the CADPIPE program has been revised and new item codes added, which the interface program is unaware of. As before, the interface program will have to be modified to handle this condition. The user should contact COADE and inform the CAESAR II Technical Support staff of this error message. The reassembly of a geometry containing OLETS should be checked carefully. OLET entities in the CADPIPE connectivity file do not contain a reference to the piping element they intersect. The interface attempts to determine the associated pipe via coordinate computation and 3D intersection calculations. There is the potential for this procedure to pass over the intersection point. In this case, the branch containing the OLET will plot at the origin of the CAESAR II model. This condition can be fixed in the CAESAR II input by breaking the intersected pipe and assigning the OLET node number to the break point. Some CADPIPE connectivity files which have been submitted to COADE for analysis contained errors. These errors consisted of either pipe doubling back on itself, or piping elements indicated as bends where there was no change in direction. Both of these errors will be detected by the CAESAR II error checker. However, most users quit before that stage and conclude that the interface is wrong. Both of these errors should be detected in CADPIPE before the connectivity file is generated.

ComputerVision Interface The interface between CAESAR II and ComputerVision is a one way transfer of the geometry data from ComputerVision to CAESAR II. The geometry data consists of the pipe lengths, diameters, thicknesses, connectivities, and node numbers. All nodal specific quantities (restraints, loads, displacements, etc.) must be added to the CAESAR II input file in the usual manner by the user. The ComputerVision interface is set up so that several models can be transferred in a single session. The first prompt by the interface is for the name of the ComputerVision neutral file. Once the user specifies this file name, the transfer process occurs and the interface program prompts for another neutral file name. This is an endless cycle until the user terminates the session by pressing the Cancel button. The neutral file read by the interface must be generated by the ComputerVision “EXTRACT PIPE” module. Details of this step can be found in the ComputerVision documentation. The ComputerVision neutral file must be transferred into the CAESAR II directory so that it is available to the interface program. The interface program reads the ComputerVision neutral file and generates the CAESAR II input file and a log file of the transfer process. Users should check the data in both the CAESAR II input file and the log file for consistency and any assumptions made by the interface.

Chapter 8 Interfaces

25

ComputerVision Interface Prompts Once the ComputerVision interface is started, it prompts the user for the name of the neutral file to be translated. The user must enter the full file name (prefix, dot, suffix) correctly, or the prompt is repeated. The interface checks for the file’s existence and then prompts for an arbitrary coordinate conversion factor. An affirmative response to this query produces a prompt for the conversion factor. This conversion factor is used to ensure the coordinates are in the same units as the diameters and thicknesses. The interface then prompts the user for the location in the neutral file of the tangent intersection points (TIPTs) of the elbows. Normally, the TIPTs of the bends will be in the section of the neutral file labeled component data. If this is the case, answer [Y] to the prompt, otherwise answer [N]. Note: The interface will not translate the geometry properly if the TIPTs for some bends is in the component data, while the TIPTs for other bends is in the grid data. After these prompts have been answered, the interface translates the ComputerVision neutral file and displays the name of the generated CAESAR II input file. The interface then prompts for the name of another neutral file for conversion and the cycle is repeated.

ComputerVision Neutral File The ComputerVision neutral file is a standard ASCII text file generated by the “EXTRACT PIPE” module. The data for the piping system is broken down into distinct sections in the neutral file as outlined below: General Data. Defines the line name and the units system used to generate the neutral file. The current CAESAR II units file should match this units specification, or utilize the “arbitrary conversion factor” discussed above. Anchor Data. Defines the coordinates of points described as anchors to the system. Grid Data. Defines the coordinates of the other nodal points in the system. Member Data. Describes the element connectivity of the system and references special conditions to the Component Data. Component Data. Defines the coordinates of bend tangent intersection points. Section Data. Defines the diameter and wall thickness of the various pipe cross sections used in the Member Data. The other sections of the neutral file are not utilized by the interface program. One assumption made by the interface is that each of the sections are separated in the file by a blank line. This is important, depending on how the neutral file was transferred to the CAESAR II directory on the PC. Some communication setups compress out blank lines, which will cause the interface to abort with an error message.

26

CAESAR II Technical Reference Manual

CAESAR II Log File The log file generated by the interface contains an image of the data utilized from the neutral file. This data consists of the Anchor data, the Grid data, the Member data, the Component data, and the Section data. Note that the node numbers are reassigned, starting with and incrementing by tens. Following the image of the neutral file is the interpreted data, listed in the standard CAESAR II data matrix format.

Checking the ComputerVision/CAESAR II Data Transfer It is very important that the resulting CAESAR II input file be verified by the user. The first step in the verification process is the review of the log file to see if the interpreted data makes sense. The .LOG file is a standard ASCII text file which can be printed on the system printer or scanned with a text editor. The second step is to enter the input mode of the CAESAR II program and plot the model. The CAESAR II plot for the ComputerVision example is shown in the following figure.

Intergraph Interface This interface transfers a piping system geometry from an Intergraph neutral file into a standard CAESAR II binary input file. The geometry data consists of the pipe lengths, diameters, thicknesses, connectivities, and node numbers. All nodal specific quantities (loads, displacements, etc.) must be added to the CAESAR II input file in the usual manner by the user. There are three basic steps necessary to generate a CAESAR II input file from an Intergraph neutral file: 1

Run the Intergraph PDS Interface module to create an Intergraph neutral file. This ASCII file should then be transferred to the CAESAR subdirectory.

Chapter 8 Interfaces

2

As many Intergraph neutral files as necessary may be created and transferred. The interface will continue to prompt the user for neutral file names, until the session is terminated by the user by clicking the Cancel button.

3

Ensure the proper units file is active in the directory in which the neutral file is located. This is necessary for the proper conversion of the data.

27

Start CAESAR II as usual and enter the TOOLS - EXTERNAL INTERFACES- INTERGRAPH and answer the prompts.

File Name This is the full path name to the neutral file, which must include the file suffix. On startup, this field is filled with the current data path. You can manually add a file name to the end of this string, or use the Browse button to search for a neutral file.

Browse This button invokes a standard file selection dialog box from which you can search for the desired neutral file. The top of this dialog contains controls for switching directories or drives, while the bottom of this dialog contains a control to switch between the neutral file suffix types (.N or .NEU).

28

CAESAR II Technical Reference Manual

Minimum Anchor Node This edit box allows the user to change the node number interpreted as the minimum node number for a terminal point in the model. You should only change the default value if your Intergraph system has been set up with a different anchor node range.

Maximum Anchor Node This edit box allows the user to change the node number interpreted as the maximum node number for a terminal point in the model. You should only change the default value if your Intergraph system has been set up with a different anchor node range.

Starting Node Number This edit box allows you to specify the starting node number in the resulting CAESAR II model. The entire model will be renumbered (by default) using this value as the starting point for the model. To disable renumbering, this value must be set to zero (as well as the node number increment).

Node Number Increment This edit box allows you to specify the value used as a node number increment, employed during the renumbering of the model. To disable renumbering, this value must be set to zero (as well as the starting node number.

Filter Out Elements Whose Diameter is Less Than This edit box is used to define a minimum allowed pipe size. Any elements less than this minimum diameter will be ignored. The purpose of this entry is to keep drain lines and taps out of the stress model.

Remove HA Elements This check box determines whether or not HA elements are removed by this interface. Normally HA (hanger-support direction) elements should be removed. The support is placed on the pipe where the HA element joints it. Unchecking this box leaves HA elements in the stress model.

Force Consistent Bend Materials This check box allows the interface to insure that all bend elements (incoming and outgoing) have the same material name and properties. Often, bends are given a different material name than that of the attached piping, while the properties are the same. This check box allows the program to change the material information as necessary on the bend elements to that of the attached piping.

Include Additional Bend Nodes This check box allows the interface to add a mid-point node and a near-point node on bends. Unchecking this box causes bends to have only the far-point node.

Enable Advanced Element Sort This check box allows a second, more thorough sorting of the elements. This sort considers the length of the runs, the diameter, and the elevation in determining where to begin the node numbering sequence. (This option is enabled by default). Turning this option off employs only the first sort where the elements are sorted starting with the largest (diameter) anchor nodes and proceeds to the smallest.

Chapter 8 Interfaces

29

Model Tees as 3 Elements This option instructs the software to treat tees as 3 elements, instead of condensing them down to a point. In either case, the SIF is applied at the tee node. Using 3 elements allows pipe properties of the tee to differ from the attached piping.

Model Rotation This group of radio buttons is used to specify the rotation of the model about the Y axis. The default is zero which leaves the model alone. The +90 button rotates the model a positive 90 degrees, while the -90 button rotates the model a negative 90 degrees. (Note, the Y axis is vertical in CAESAR II.)

Weight Units This set of radio buttons enables the software to properly interpret the 'weight' values contained in the neutral file. This is necessary since the neutral file does not indicate the units for the weight values. The value selected here should match the corresponding value in the active CAESAR II units file.

Insulation Units This set of radio buttons enables the software to properly interpret the 'insulation thickness' values contained in the neutral file. This is necessary since the neutral file does not indicate the units for insulation thickness values. The value selected here should match the corresponding value in the active CAESAR II units file. Once the Intergraph interface program returns control to the Main Menu, the CAESAR II binary input files are available for access. The following modifications and additions will be necessary: Specification of material properties; Material 1 is assumed, unless a material mapping file is provided. The material mapping file is discussed below. Specification of temperatures and pressures; the temperature/pressure pairs are assigned to T1, T2, T3 and P1, and P2 in order. Specification of intersection types; unreinforced is assumed. Specification of restraints details. By default, only anchors and double acting supports are detected by the interface. If the exact type of restraint is to be transferred, the PDS system must be configured to generate the CAESAR II restraint type indicators. These restraint type indicators are shown in the "Additional Notes" section of the "complete Neutral File" interface, discussed later in this chapter. These restraint type values must be placed in field 7 of the first "HA" property card to be recognized by CAESAR II. Specification of other loads. The weight of rigid elements can be transferred into CAESAR II for "3W", "4W", "AV", "RB", and "VA" type elements. In order for the weight of these elements to transfer, the weight value must be placed in field 8 of the first property card. Insulation thickness and density can be transferred into CAESAR II also. The thickness and density values should be placed in fields 9 and 10 of the first PROP card. In addition, the LOG file generated by the interface should be reviewed for any anomalies. The interface sorts the elements and then insures that diameters and wall thicknesses are defined for each element. Depending on how disorganized the Intergraph neutral file is, some assumptions made by the interface may not be correct and therefore require modification of the resulting CAESAR II input file. Any major problems encountered by the interface cause the program to abort and no CAESAR II input is generated. Users experiencing problems of this nature should forward their neutral files to COADE for analysis and subsequent program modification.

30

CAESAR II Technical Reference Manual

If desired, a material mapping file may be defined to relate the material designations in the Intergraph neutral file to the standard CAESAR II materials. This file must be named "PDS_MAT.MAP" and it must be located beneath the CAESAR II program directory, in the \SYSTEM subdirectory. This mapping file contains two fields of data per line. Field 1 contains the PDS material name as it will appear in the neutral file, and is 16 characters wide. Field 2 contains the CAESAR II material number corresponding to the PDS material name. These values should contain a decimal point, and lie in columns 17 thru 21. The following paragraphs describe the layout of the data extracted from the Intergraph neutral file and how it is arranged for storage in this interface program. The data storage is maintained in two arrays, the first contains geometry data for each pipe element, the second array contains additional loading and specification data. In the first array, an entry is required for each piece of pipe in the system. A “pipe” in this sense is an entity between two nodes, which could be a pipe, or a rigid element. There are 12 values per entry, where all values must be specified. Field 1 - ELMT. This is the pipe element number, which may correspond to an entry in the second array. This is also the pipe/element number in the model. These values should be sequential from 1. Field 2 - N1. This is the “FROM” node number, i.e. the starting node for the element. These values must be greater than zero and less than 32000. Field 3 - N2. This is the “TO” node number, i.e. the ending node for the element. These values must be greater than zero and less than 32000. Field 4 - DX. This is the “delta X” dimension for the element. This is the distance between N1 and N2 in the “X” direction. Field 5 - DY. This is the “delta Y” dimension for the element. This is the distance between N1 and N2 in the “Y” direction. In CAESAR II, “Y” is vertical. Field 6 - DZ. This is the “delta Z” dimension for the element. This is the distance between N1 and N2 in the “Z” direction. Field 7 - DIAM. This is the pipe outer diameter. Field 8 - THK. This is the pipe wall thickness. Field 9 - ANCH. This is a restraint (support) indicator flag. If ANCH is 1, then there is a restraint on N1. If ANCH is 2, then there is a restraint on N2. The type of restraint can be obtained from the second array. Field 10 - BND. This field indicates the presence of a bend at the N2 end of the element. If BND is 1, there is a bend at N2. If BND is 0, this is a straight pipe. Field 11 - BRAD. This field is used to specify the bend radius if the bend is not a long radius bend. The value here should be the desired bend radius. Field 12 - RIGD. This field is a flag used to indicate that the current element is a rigid element. The weight of the element can be obtained from the second array. Records in the second array are only necessary when additional data is required. This means there will always be a record in first array for pipe element #1 (this could be the only entry in the array). Any additional entries will contain some type of change to data normally duplicated forward by CAESAR II.

Chapter 8 Interfaces

31

Field 1 - ELMT. This is the pipe element number, which corresponds to an entry in the first array. This is also a pipe/element number in the model. These numbers are sequential from 1. Field 2 - TEMP1. This is the operating temperature for load case 1, found by scanning the Intergraph data. Field 3 - PRESS1. This is the operating pressure for load case 1, found by scanning the Intergraph data. Field 4 - RGDWGT. This value is the weight of rigid elements. This entry is only required if the “RIGID” flag was set in the first array. Field 5 - TEEFLG. This value indicates the “TEE” type. 1 - reinforced 2 - unreinforced 3 - welding tee 4 - sweepolet 5 - weldolet 6 - extruded welding tee Field 6 - RESTYP. This value is the restraint (support) type indicator. Type values are defined in the "Additional Notes" section of the "Complete Neutral File" interface, discussed later in this chapter. Field 7 - RINFO1. Data for supports, by default, the restraint stiffness. Field 8 - RINFO2. Data for supports, by default, the restraint gap. Field 9 - RINFO3. Data for supports, by default, the restraint friction coefficient. Field 10 - MATID. The standard CAESAR II material ID value (1-17). Note that if the coefficient of expansion is to be changed, it should be entered in the Temperature field above (Field 2). Field 11 - EMOD. The value of Young’s modulus. Field 12 - POIS. The value of Poisson’s ratio. Field 13 - GAMMA. The weight density of the material. Field 14 - INSTHK. The insulation thickness. Field 15 - INSWGT. The weight density of the insulation material. Field 16 - FLDWGT. The weight density of the pipe contents (fluid). Field 17 - TEENOD. The element node number where there is a tee. Field 18 - TEMP2. This case is the temperature for operating case 2.

32

CAESAR II Technical Reference Manual

Field 19 - TEMP3. This is the temperature for operating case 3. Field 20 - PRESS2. This is a second pressure specification

Chapter 8 Interfaces

Example Transfer Listed as follows is an example neutral file from the PDS system. ! Model Design file(s) : ZG2:[006,006]MDLTEST.DGN !

: ZG2:[006,006]EQPTEST.DGN

! Line name(s)

: P-1002

! Date

: 26-JUL-89 13:58:12

DRAW ,P-1002,P-1002 LOAD, 202000E, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 202000E, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LOAD, 102001F, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 102001F, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LOAD, 202000F, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 202000F, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LOAD, 102001A, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 102001A, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LOAD, 102001D, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 102001D, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LSET, 202000E,3,6,5,3

LSET, 102001F,3,6,5,3

LSET, 202000F,3,6,5,3

LSET, 102001A,3,6,5,3

LSET, 102001D,3,6,5,3

33

34

CAESAR II Technical Reference Manual

LOAD, 1020020, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 1020020, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LOAD, 1020023, 1, 3, 500.00

100.00,

300.00,

0.00,

0.00,

300.00,

LOAD, 1020023, 4, 6, 0.00

200.00,

400.00,

0.00,

0.00,

0.00,

LSET, 1020020,3,6,5,3

LSET, 1020023,3,6,5,3 CODE,CODE23,ASME2,1982,D TF, 3020009,16"x10"STDCB390155,,CODE23,

25,

24

PROP,TF, 3020009, 1,A105,0,0,0,0,0,0. PROP,TF, 3020009, 2,0,0.0,90 PROP,TF, 3020009, 3,16.,16,BE,0.375,, 202000E PROP,TF, 3020009, 4,10.,10.75,BE,0.365,, 102001F RB, 302000B,16"STDCB30255,,CODE23, 901,

26

PROP,RB, 302000B, 1,A234-WPB,0,0,0,0,0,0. PROP,RB, 302000B, 3,16.,16,BW,0.375,, 202000E PROP,RB, 302000B, 4,0.,0,BW,0.,, 202000E PI, 5020013,16"STDCB10075,,CODE23,

26,

25

PROP,PI, 5020013, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020013, 3,16.,16,BW,0.375,, 202000E PROP,PI, 5020013, 4,16.,16,BW,0.375,, 202000E RB, 302000A,16"STDCB30255,,CODE23, 902,

12

PROP,RB, 302000A, 1,A234-WPB,0,0,0,0,0,0. PROP,RB, 302000A, 3,16.,16,BW,0.375,, 202000F PROP,RB, 302000A, 4,0.,0,BW,0.,, 202000F TF, 302000C,16"x10"STDCB390155,,CODE23,

15,

14

Chapter 8 Interfaces

PROP,TF, 302000C, 1,A105,0,0,0,0,0,0. PROP,TF, 302000C, 2,0,0.0,90 PROP,TF, 302000C, 3,16.,16,BE,0.375,, 202000F PROP,TF, 302000C, 4,10.,10.75,BE,0.365,, 102001A PI, 5020014,16"STDCB10075,,CODE23,

17,

15

PROP,PI, 5020014, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020014, 3,16.,16,BW,0.375,, 102001D PROP,PI, 5020014, 4,16.,16,BW,0.375,, 102001D FL, 3020042,10"STDCB20015,,CODE23,

27,

13

PROP,FL, 3020042, 1,A105,0,0,0,0,0,0. PROP,FL, 3020042, 3,10.,16,WN,0.,CL150, 102001A PROP,FL, 3020042, 4,10.,10.75,BW,0.365,CL150, 102001A PI, 5020015,10"STDCB10075,,CODE23,

14,

13

PROP,PI, 5020015, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020015, 3,10.,10.75,BW,0.365,, 102001A PROP,PI, 5020015, 4,10.,10.75,BW,0.365,, 102001A TE, 3020008,16"STDCB30245,,CODE23,

22,

17,

20, 951

PROP,TE, 3020008, 1,A234-WPB,0,0,0,0,0,0. PROP,TE, 3020008, 2,0,0.0,90 PROP,TE, 3020008, 3,16.,16,BW,0.375,, 1020020 PROP,TE, 3020008, 4,16.,16,BW,0.375,, 102001D PROP,TE, 3020008, 5,16.,16,BW,0.375,, 1020023 FL, 3020041,10"STDCB20015,,CODE23,

28,

23

PROP,FL, 3020041, 1,A105,0,0,0,0,0,0. PROP,FL, 3020041, 3,10.,16,WN,0.,CL150, 102001F PROP,FL, 3020041, 4,10.,10.75,BW,0.365,CL150, 102001F PI, 5020012,10"STDCB10075,,CODE23,

23,

24

35

36

CAESAR II Technical Reference Manual

PROP,PI, 5020012, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020012, 3,10.,10.75,BW,0.365,, 102001F PROP,PI, 5020012, 4,10.,10.75,BW,0.365,, 102001F EL, 3020040,16"STDCB30215,,CODE23, 903,

1, 952

PROP,EL, 3020040, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 3020040, 2,24,90,0,0. PROP,EL, 3020040, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 3020040, 4,16.,16,BW,0.375,, 1020023 EL, 3020023,16"STDCB30215,,CODE23,

18,

16, 953

PROP,EL, 3020023, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 3020023, 2,24,90,0,0. PROP,EL, 3020023, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 3020023, 4,16.,16,BW,0.375,, 1020023 EL, 3020024,16"STDCB30215,,CODE23,

16,

10, 954

PROP,EL, 3020024, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 3020024, 2,24,90,0,0. PROP,EL, 3020024, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 3020024, 4,16.,16,BW,0.375,, 1020023 EL, 302002A,16"STDCB30215,,CODE23,

11,

9, 955

PROP,EL, 302002A, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 302002A, 2,24,90,0,0. PROP,EL, 302002A, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 302002A, 4,16.,16,BW,0.375,, 1020023 EL, 302002B,16"STDCB30215,,CODE23,

8,

6, 956

PROP,EL, 302002B, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 302002B, 2,24,90,0,0. PROP,EL, 302002B, 3,16.,16,BW,0.375,, 1020023

Chapter 8 Interfaces

PROP,EL, 302002B, 4,16.,16,BW,0.375,, 1020023 EL, 302003C,16"STDCB30235,,CODE23,

5,

3, 957

PROP,EL, 302003C, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 302003C, 2,24.1421,45,0,0. PROP,EL, 302003C, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 302003C, 4,16.,16,BW,0.375,, 1020023 EL, 302003D,16"STDCB30215,,CODE23,

4,

2, 958

PROP,EL, 302003D, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 302003D, 2,24,90,0,0. PROP,EL, 302003D, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 302003D, 4,16.,16,BW,0.375,, 1020023 PI, 5020016,16"STDCB10075,,CODE23,

19,

18

PROP,PI, 5020016, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020016, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 5020016, 4,16.,16,BW,0.375,, 1020023 PI, 5020018,16"STDCB10075,,CODE23,

10,

11

PROP,PI, 5020018, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020018, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 5020018, 4,16.,16,BW,0.375,, 1020023 PI, 5020019,16"STDCB10075,,CODE23,

9,

8

PROP,PI, 5020019, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5020019, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 5020019, 4,16.,16,BW,0.375,, 1020023 PI, 502001A,16"STDCB10075,,CODE23,

6,

7

PROP,PI, 502001A, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 502001A, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 502001A, 4,16.,16,BW,0.375,, 1020023

37

38

CAESAR II Technical Reference Manual

PI, 502001B,16"STDCB10075,,CODE23,

3,

4

PROP,PI, 502001B, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 502001B, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 502001B, 4,16.,16,BW,0.375,, 1020023 PI, 502001C,16"STDCB10075,,CODE23,

2,

1

PROP,PI, 502001C, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 502001C, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 502001C, 4,16.,16,BW,0.375,, 1020023 EL, 302003E,16"STDCB30235,,CODE23,

5,

7, 959

PROP,EL, 302003E, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 302003E, 2,24.1421,45,0,0. PROP,EL, 302003E, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 302003E, 4,16.,16,BW,0.375,, 1020023 EL, 302005A,16"STDCB30215,,CODE23,

19,

21, 960

PROP,EL, 302005A, 1,A234-WPB,0,0,0,0,0,0. PROP,EL, 302005A, 2,24,90,0,0. PROP,EL, 302005A, 3,16.,16,BW,0.375,, 1020023 PROP,EL, 302005A, 4,16.,16,BW,0.375,, 1020023 PI, 502005E,16"STDCB10075,,CODE23,

21,

20

PROP,PI, 502005E, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 502005E, 3,16.,16,BW,0.375,, 1020023 PROP,PI, 502005E, 4,16.,16,BW,0.375,, 1020023 PI, 5027531,16"STDCB10075,,CODE23,

25,

22

PROP,PI, 5027531, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5027531, 3,16.,16,BW,0.375,, 1020020 PROP,PI, 5027531, 4,16.,16,BW,0.375,, 1020020 PI, 5027532,16"STDCB10075,,CODE23,

15,

12

Chapter 8 Interfaces

PROP,PI, 5027532, 1,API-5L-B,0.0000E+00,0.0000E+00,,0,,0.0000E+00 PROP,PI, 5027532, 3,16.,16,BW,0.375,, 202000F PROP,PI, 5027532, 4,16.,16,BW,0.375,, 202000F LNOD,

27,RE, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0

LNOD,

28,RE, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0

NODE,

1,

12024.00,

12000.00,

3011.12,

2,

0.00

NODE,

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12044.50,

12000.00,

3011.12,

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0.00

NODE,

3,

12068.50,

12000.00,

2470.00,

2,

0.00

NODE,

4,

12068.50,

12000.00,

2987.12,

2,

0.00

NODE,

5,

12075.57,

12000.00,

2452.93,

2,

0.00

NODE,

6,

12082.64,

12000.00,

1764.00,

2,

0.00

NODE,

7,

12082.64,

12000.00,

2435.86,

2,

0.00

NODE,

8,

12106.64,

12000.00,

1740.00,

2,

0.00

NODE,

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12168.00,

12000.00,

1740.00,

2,

0.00

NODE,

10,

12192.00,

11815.00,

1740.00,

2,

0.00

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11,

12192.00,

11976.00,

1740.00,

2,

0.00

NODE,

12,

12198.00,

11911.00,

1644.00,

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NODE,

13,

12210.00,

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12210.00,

11911.00,

1632.94,

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0.00

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15,

12210.00,

11911.00,

1644.00,

2,

0.00

NODE,

16,

12216.00,

11791.00,

1740.00,

2,

0.00

NODE,

17,

12228.00,

11911.00,

1644.00,

2,

0.00

NODE,

18,

12240.00,

11815.00,

1740.00,

2,

0.00

NODE,

19,

12240.00,

11887.00,

1740.00,

2,

0.00

NODE,

20,

12240.00,

11911.00,

1656.00,

2,

0.00

NODE,

21,

12240.00,

11911.00,

1716.00,

2,

0.00

NODE,

22,

12252.00,

11911.00,

1644.00,

2,

0.00

39

40

CAESAR II Technical Reference Manual

NODE,

23,

12270.00,

11911.00,

1594.12,

2,

0.00

NODE,

24,

12270.00,

11911.00,

1632.94,

2,

0.00

NODE,

25,

12270.00,

11911.00,

1644.00,

2,

0.00

NODE,

26,

12282.00,

11911.00,

1644.00,

2,

0.00

NODE,

27,

12210.00,

11911.00,

1590.05,

2,

0.00

NODE,

28,

12270.00,

11911.00,

1590.05,

2,

0.00

NODE,

901,

12285.50,

11911.00,

1644.00,

2,

0.00

NODE,

902,

12194.50,

11911.00,

1644.00,

2,

0.00

NODE,

903,

12000.00,

12000.00,

2987.12,

2,

0.00

NODE,

904,

12210.00,

11911.00,

1577.18,

2,

0.00

NODE,

905,

12270.00,

11911.00,

1577.18,

2,

0.00

NODE,

951,

12240.00,

11911.00,

1644.00,

2,

0.00

NODE,

952,

12000.00,

12000.00,

3011.12,

2,

0.00

NODE,

953,

12240.00,

11791.00,

1740.00,

2,

0.00

NODE,

954,

12192.00,

11791.00,

1740.00,

2,

0.00

NODE,

955,

12192.00,

12000.00,

1740.00,

2,

0.00

NODE,

956,

12082.64,

12000.00,

1740.00,

2,

0.00

NODE,

957,

12068.50,

12000.00,

2460.00,

2,

0.00

NODE,

958,

12068.50,

12000.00,

3011.12,

2,

0.00

NODE,

959,

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2,

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NODE,

960,

12240.00,

11911.00,

1740.00,

2,

0.00

The .LOG file produced by the CAESAR II translator is shown below, followed by a plot of the job from the CAESAR II input module.

*** CAESAR II / Intergraph Geometry Translator *** INTERGRAPH DATA AS READ IN FOR FILE: P-1002.NEU

Chapter 8 Interfaces

Maximum Temperature and Pressure encountered: Looking for node:

300.0

901

Have sorted element:

1, its location pointer is:

Number of “resume” nodes is:

2

0

Element type is: 10

Looking for node:

26

Have sorted element:

2, its location pointer is:

Number of “resume” nodes is: Element type is:

3

0

9

Looking for node:

25

Have sorted element:

3, its location pointer is:

Number of “resume” nodes is:

1

0

Element type is: 14

Looking for node:

24

Have sorted element:

4, its location pointer is:

Number of “resume” nodes is: Element type is:

0

9

Looking for node:

23

Have sorted element:

5, its location pointer is:

Number of “resume” nodes is: Element type is:

11

7

0

10

500.0

41

42

CAESAR II Technical Reference Manual

Looking for node:

28

Looking for node:

902

Have sorted element:

6, its location pointer is:

Number of “resume” nodes is:

4

0

Element type is: 10 Looking for node:

12

Have sorted element:

7, its location pointer is:

Number of “resume” nodes is: Element type is:

29

0

9

Looking for node:

15

Have sorted element:

8, its location pointer is:

Number of “resume” nodes is:

5

0

Element type is: 14

Looking for node:

14

Have sorted element:

9, its location pointer is:

Number of “resume” nodes is: Element type is:

0

9

Looking for node:

13

Have sorted element:

10, its location pointer is:

Number of “resume” nodes is: Element type is:

8

7

0

7

Chapter 8 Interfaces

Looking for node:

27

Looking for node:

903

Have sorted element:

11, its location pointer is:

Number of “resume” nodes is: Element type is:

1

Have sorted element:

12, its location pointer is:

Number of “resume” nodes is:

13, its location pointer is:

Number of “resume” nodes is:

18

0

5

Looking for node:

4

Have sorted element:

14, its location pointer is:

Number of “resume” nodes is:

23

0

9

Looking for node:

3

Have sorted element:

15, its location pointer is:

Number of “resume” nodes is: Element type is:

0

2

Have sorted element:

Element type is:

24

9

Looking for node:

Element type is:

0

5

Looking for node:

Element type is:

12

17

0

5

Looking for node: Have sorted element:

5 16, its location pointer is:

25

43

44

CAESAR II Technical Reference Manual

Number of “resume” nodes is: Element type is:

5

Looking for node:

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Have sorted element:

17, its location pointer is:

Number of “resume” nodes is: Element type is:

18, its location pointer is:

Number of “resume” nodes is:

0

8

Have sorted element:

19, its location pointer is:

Number of “resume” nodes is:

21

0

9

Looking for node:

9

Have sorted element:

20, its location pointer is:

Number of “resume” nodes is:

15

0

5

Looking for node:

11

Have sorted element:

21, its location pointer is:

Number of “resume” nodes is: Element type is:

16

5

Looking for node:

Element type is:

0

6

Have sorted element:

Element type is:

22

9

Looking for node:

Element type is:

0

9

0

20

Chapter 8 Interfaces

Looking for node:

10

Have sorted element:

22, its location pointer is:

Number of “resume” nodes is: Element type is:

0

5

Looking for node:

16

Have sorted element:

23, its location pointer is:

Number of “resume” nodes is: Element type is:

5

18

Have sorted element:

24, its location pointer is:

Number of “resume” nodes is: 9

19

Have sorted element:

25, its location pointer is:

Number of “resume” nodes is: 5

21

Have sorted element:

26, its location pointer is:

Number of “resume” nodes is:

Looking for node:

26

0

Looking for node:

Element type is:

19

0

Looking for node:

Element type is:

13

0

Looking for node:

Element type is:

14

9

20

0

27

45

46

CAESAR II Technical Reference Manual

Have sorted element:

27, its location pointer is:

Number of “resume” nodes is:

9

0

Element type is: 13

Looking for node:

22

Have sorted element:

28, its location pointer is:

Number of “resume” nodes is: Element type is:

1

9

Looking for node:

25

Looking for node:

17

Have sorted element:

29, its location pointer is:

Number of “resume” nodes is: Element type is:

Looking for node:

28

9

15

0

6

Chapter 8 Interfaces

Intergraph Data After Element Sort

47

48

CAESAR II Technical Reference Manual

Intergraph Data After TEE/Cross Modifications

Chapter 8 Interfaces

49

(End nodes replaced with center point, and TEE/CROSS element removed. Modifications also performed on 3 & 4 way valves.)

Intergraph Data After Valve Modifications

50

CAESAR II Technical Reference Manual

(Flange lengths added to valve lengths.)

** BEND MODIFICATION START ** INCOMING ELEMENT:

11

NODES:

1

903

BEND ELEMENT

:

11

NODES:

903

1

EXITING ELEMENT :

12

NODES:

1

2

CURRENT COORDINTES FOR ELEMENT:

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NODE:

1

X, Y, Z =

12024.00

3011.12 -12000.00

NODE:

903

X, Y, Z =

12000.00

2987.12 -12000.00

CURRENT COORDINTES FOR ELEMENT:

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NODE:

1

X, Y, Z =

12024.00

3011.12 -12000.00

NODE:

2

X, Y, Z =

12044.50

3011.12 -12000.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

1

X, Y, Z =

12000.00

3011.12 -12000.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

13

NODES:

4

2

BEND ELEMENT

:

13

NODES:

2

4

EXITING ELEMENT :

14

NODES:

4

3

CURRENT COORDINTES FOR ELEMENT:

13

NODE:

4

X, Y, Z =

12068.50

2987.12 -12000.00

NODE:

2

X, Y, Z =

12044.50

3011.12 -12000.00

Chapter 8 Interfaces

CURRENT COORDINTES FOR ELEMENT:

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NODE:

4

X, Y, Z =

12068.50

2987.12 -12000.00

NODE:

3

X, Y, Z =

12068.50

2470.00 -12000.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

4

X, Y, Z =

12068.50

3011.12 -12000.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

15

NODES:

5

3

BEND ELEMENT

:

15

NODES:

3

5

EXITING ELEMENT :

16

NODES:

5

7

CURRENT COORDINTES FOR ELEMENT:

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NODE:

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X, Y, Z =

12075.57

2452.93 -12000.00

NODE:

3

X, Y, Z =

12068.50

2470.00 -12000.00

CURRENT COORDINTES FOR ELEMENT:

16

NODE:

5

X, Y, Z =

12075.57

2452.93 -12000.00

NODE:

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X, Y, Z =

12082.64

2435.86 -12000.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

5

X, Y, Z =

12068.50

2460.00 -12000.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

16

NODES:

7

5

BEND ELEMENT

:

16

NODES:

5

7

EXITING ELEMENT :

17

NODES:

7

6

51

52

CAESAR II Technical Reference Manual

CURRENT COORDINTES FOR ELEMENT:

16

NODE:

7

X, Y, Z =

12082.64

2435.86 -12000.00

NODE:

5

X, Y, Z =

12068.50

2460.00 -12000.00

CURRENT COORDINTES FOR ELEMENT:

17

NODE:

7

X, Y, Z =

12082.64

2435.86 -12000.00

NODE:

6

X, Y, Z =

12082.64

1764.00 -12000.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

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X, Y, Z =

12082.64

2445.86 -12000.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

18

NODES:

8

6

BEND ELEMENT

:

18

NODES:

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EXITING ELEMENT :

19

NODES:

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NODE:

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NODE:

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X, Y, Z =

12082.64

1764.00 -12000.00

CURRENT COORDINTES FOR ELEMENT:

19

NODE:

8

X, Y, Z =

12106.64

1740.00 -12000.00

NODE:

9

X, Y, Z =

12168.00

1740.00 -12000.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

8

X, Y, Z =

12082.64

1740.00 -12000.00

Chapter 8 Interfaces

** BEND MODIFICATION START ** INCOMING ELEMENT:

20

NODES:

11

9

BEND ELEMENT

:

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NODES:

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11

EXITING ELEMENT :

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NODES:

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NODE:

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NODE:

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X, Y, Z =

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1740.00 -12000.00

CURRENT COORDINTES FOR ELEMENT:

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NODE:

11

X, Y, Z =

12192.00

1740.00 -11976.00

NODE:

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X, Y, Z =

12192.00

1740.00 -11815.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

11

X, Y, Z =

12192.00

1740.00 -12000.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

22

NODES:

16

10

BEND ELEMENT

:

22

NODES:

10

16

EXITING ELEMENT :

23

NODES:

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18

CURRENT COORDINTES FOR ELEMENT:

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NODE:

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X, Y, Z =

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1740.00 -11791.00

NODE:

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X, Y, Z =

12192.00

1740.00 -11815.00

CURRENT COORDINTES FOR ELEMENT: NODE:

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X, Y, Z =

23 12216.00

1740.00 -11791.00

53

54

CAESAR II Technical Reference Manual

NODE:

18

X, Y, Z =

12240.00

1740.00 -11815.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

16

X, Y, Z =

12192.00

1740.00 -11791.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

23

NODES:

18

16

BEND ELEMENT

:

23

NODES:

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18

EXITING ELEMENT :

24

NODES:

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19

CURRENT COORDINATES FOR ELEMENT:

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NODE:

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X, Y, Z =

12240.00

1740.00 -11815.00

NODE:

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X, Y, Z =

12192.00

1740.00 -11791.00

CURRENT COORDINTES FOR ELEMENT:

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NODE:

18

X, Y, Z =

12240.00

1740.00 -11815.00

NODE:

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1740.00 -11887.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

18

X, Y, Z =

12240.00

1740.00 -11791.00

** BEND MODIFICATION START ** INCOMING ELEMENT:

25

NODES:

21

19

BEND ELEMENT

:

25

NODES:

19

21

EXITING ELEMENT :

26

NODES:

21

951

CURRENT COORDINTES FOR ELEMENT:

25

Chapter 8 Interfaces

NODE:

21

X, Y, Z =

12240.00

1716.00 -11911.00

NODE:

19

X, Y, Z =

12240.00

1740.00 -11887.00

CURRENT COORDINTES FOR ELEMENT:

26

NODE:

21

X, Y, Z =

12240.00

1716.00 -11911.00

NODE:

951

X, Y, Z =

12240.00

1644.00 -11911.00

— COMPUTED TANGENT INTERSECTION POINT — NODE:

21

X, Y, Z =

12240.00

1740.00 -11911.00

55

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Intergraph Data After Bend Modifications

Chapter 8 Interfaces

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(Far Weld Line Nodal coordinates changed to Tangent Intersection Point coordinates)

DATA FOR PROPERTY ARRAY WITH # ENTRIES = 5

LOCATIONS 1-11

LOCATIONS 1, 12-20

*** CAESAR II INTERPRETED GEOMETRY DATA ***

*** CAESAR II INTERPRETED PROPERTY DATA ***

Part 1

*** CAESAR II INTERPRETED PROPERTY DATA ***

Part 2

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The CAESAR II job file name is P-1002_A Y Starting generation of CAESAR II input file for: 28 elements 9 Bends 2 Rigids 2 Restraints Conversion of data to CAESAR II completed

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PRO-ISO Interface The interface between CAESAR II and PRO-ISO is a one way transfer of the geometry data from PRO-ISO to CAESAR II. The geometry data consists of the pipe lengths, diameters, thicknesses, connectivities, and node numbers. All nodal specific quantities (restraints, loads, displacements, etc.) must be added to the CAESAR II input file in the usual manner by the user. Select the PRO-ISO option from the TOOLS/EXTERNAL INTERFACES menu and enter the name of the PRO-ISO neutral file. Once the user specifies the name of the file (without an extension), the transfer process occurs and the interface program prompts for another neutral file name. This is an endless cycle until the user presses the Cancel button. The neutral files generated by the interface will have the suffixes .PI1 and .PI2. The neutral files read by the interface program must be generated by the PRO-ISO program. Details of this step can be found in the PRO-ISO documentation. The PRO-ISO neutral files must be transferred into the CAESAR II directory so that they are available to the interface program. The interface program reads the PRO-ISO neutral files and generates the CAESAR II input file and a log file of the transfer process. Users should check the data in both the CAESAR II input file and the log file for consistency and any assumptions made by the interface. The data transferred (and the data structure) is described below. In the first file, a record is required for each piece of pipe in the system. A “pipe” in this sense is an entity between two nodes, which could be a pipe, or a rigid element. There are 12 values per entry, where all values must be specified. Field 1 - ELMT This is the pipe element number, which may correspond to an entry in the second file. This is also the pipe/element number in the model. These values should be sequential from 1. Field 2 - N1 This is the “FROM” node number, i.e. the starting node for the element. These values must be greater than zero and less than 32000. Field 3 - N2 This is the “TO” node number, i.e. the ending node for the element. These values must be greater than zero and less than 32000. Field 4 - DX This is the “delta X” dimension for the element. This is the distance between N1 and N2 in the “X” direction. Field 5 - DY This is the “delta Y” dimension for the element. This is the distance between N1 and N2 in the “Y” direction. In CAESAR II, “Y” is vertical. Field 6 - DZ This is the “delta Z” dimension for the element. This is the distance between N1 and N2 in the “Z” direction.

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Field 7 - DIAM This is the pipe outer diameter. Field 8 - THK This is the pipe wall thickness. Field 9 - ANCH This is a restraint (support) indicator flag. If ANCH is 1, then there is a restraint on N1. If ANCH is 2, then there is a restraint on N2. The type of restraint can be obtained from the second file. Field 10 - BND This field indicates the presence of a bend at the N2 end of the element. If BND is 1, there is a bend at N2. If BND is 0, this is a straight pipe. Field 11 - BRAD This field is used to specify the bend radius if the bend is not a long radius bend. The value here should be the desired bend radius. Field 12 - RIGD This field is a flag used to indicate that the current element is a rigid element. The weight of the element can be obtained from the second file. Records in the second file are only necessary when additional data is required. This means there will always be a record in the second file for pipe element #1 (this could be the only entry in the file). Any additional entries will contain some type of change to data normally duplicated forward by CAESAR II. Field 1 - ELMT This is the pipe element number, which corresponds to an entry in the first file. This is also a pipe/element number in the model. These numbers are sequential from 1. Field 2 - TEMP1 This is the operating temperature for load case 1, found by scanning the PRO-ISO data for the maximum temperature. Field 3 - PRESS1 This is the operating pressure for load case 1, found by scanning the PRO-ISO data for the maximum pressure. Field 4 - RGDWGT This value is the weight of rigid elements. This entry is only required if the “RIGID” flag was set in the first file. Field 5 - TEEFLG

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This value indicates the “TEE” type. 1 - reinforced 2 - unreinforced 3 - welding tee 4 - sweepolet 5 - weldolet 6 - extruded welding tee Field 6 - RESTYP This value is the restraint (support) type indicator. Type values are: 0 - anchor 1 - double acting X 2 - double acting Y 3 - double acting Z 4 - double acting RX 5 - double acting RY 6 - double acting RZ Field 7 - RINFO1 Data for supports, by default, the restraint stiffness. Field 8 - RINFO2 Data for supports, by default, the restraint gap. Field 9 - RINFO3 Data for supports, by default, the restraint friction coefficient. Field 10 - MATID The CAESAR II material ID value. Note that if the coefficient of expansion is to be changed, it should be entered in the Temperature field above (Field 2). Field 11 - EMOD The value of Young’s modulus.

Chapter 8 Interfaces

Field 12 - POIS The value of Poisson’s ratio. Field 13 - GAMMA The weight density of the material. Field 14 - INSTHK The insulation thickness. Field 15 - INSWGT The weight density of the insulation material. Field 16 - FLDWGT The weight density of the pipe contents (fluid). Field 17 - TEENOD The element node number where there is a tee. Field 18 - (Placeholder for future development.) Field 19 - (Placeholder for future development.) Field 20 - (Placeholder for future development.)

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PRO-ISO Example Transfer Listed below are example neutral files produced by the PRO-ISO program. Note that the field width for each value is actually 13 characters. The figures below have been compressed for this documentation.

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As the interface runs, status messages are displayed on the user’s terminal for informative purposes. Once the transfer is complete, the user should review the .LOG file generated to insure that there are no unexplained errors or warnings. The .LOG file generated for the above neutral files is listed next.

*** CAESAR II / ADEV Geometry Translator *** ADEV data as read in for GEOMETRY file: TEST1.PI1 PROPERTY file: TEST1.PI2 Starting read of CAD

neutral files.

CAD

geometry successfully read.

CAD

properties successfully read.

*** C A E S A R I I

INTERPRETED GEOMETRY DATA ***

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*** C A E S A R II INTERPRETED PROPERTY DATA *** Part 1

*** C A E S A R II INTERPRETED PROPERTY DATA *** Part 2

Data transferred to CAESAR II array structures. The CAESAR II job file name is: TEST1._A Starting generation of CAESAR II input file for: 15 Elements 2 Bends 1 Rigids 5 Restraints Conversion of data to CAESAR II completed.

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Checking the PRO-ISO/CAESAR II Data Transfer It is very important that the resulting CAESAR II input file be verified by the user. The first step in the verification process is the review of the log file to see if any errors or warnings were generated. (The .LOG file is a standard ASCII text file which can be printed on the system printer or scanned with a text editor.) The second step is to enter the input mode of the CAESAR II program and plot the model. The CAESAR II plot for the above example is shown in the following figure.

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PCF Interface The PCF file format is a standard drawing exchange format developed by Alias Ltd. The PCF file is a flat text file, containing detailed information about the piping system components, as extracted from a CAD system. The CAESAR II PCF interface can read in a PCF file, and generate a CAESAR II input file from the acquired information. Details on the format of the PCF file, and its capabilities can be obtained from Alias. To invoke the PCF Interface select TOOLS/PCF from the CAESAR II Main Menu. A dialog box like the one below will appear. Explanations of each field are provided following the figure.

File Name This is the full path name to the neutral file, which must include the file suffix. On startup, this field is filled with the current data path. You can manually add a file name to the end of this string, or use the Browse button to search for a neutral file.

Browse This button invokes a standard file selection dialog box from which you can search for the desired neutral file. The top of this dialog contains controls for switching directories or drives, while the bottom of this dialog contains a control to switch between the neutral file suffix types (.N or .NEU).

Starting Node Number This edit box allows you to specify the starting node number in the resulting CAESAR II model. The entire model will be renumbered (by default) using this value as the starting point for the model. To disable renumbering, this value must be set to zero (as well as the node number increment).

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73

Node Number Increment This edit box allows you to specify the value used as a node number increment, employed during the renumbering of the model. To disable renumbering, this value must be set to zero (as well as the starting node number.

Condense Tees This option instructs the software NOT to treat tees as 3 elements, condensing them down to a point. In either case, the SIF is applied at the tee node. Using 3 elements allows pipe properties of the tee to differ from the attached piping.

Condense Elbows This option instructs the software NOT to treat elbows as 2 elements, one element for each direction the elbow travels in.

Condense Connected Rigids This option instructs the software to combine rigids that connect to each other into a single element.

Assume Standard Schedule This option instructs the software to compute, wall thicknesses based on the diameter of the pipe and standard schedule. Without this option, no wall thickness will be specified (for the JIS pipe specification, this option assumes Sch 40).

Model Rotation This group of radio buttons is used to specify the rotation of the model about the Y axis. The default is zero which leaves the model alone. The +90 button rotates the model a positive 90 degrees, while the -90 button rotates the model a negative 90 degrees. (Note, the Y axis is vertical in CAESAR II.)

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Generic Neutral Files CAESAR II Neutral File Interface The general neutral file can be used to send data either in to or out of the standard CAESAR II binary input file, otherwise known as the _A file. The name of the file used or generated by this interface is the CAESAR II jobname with the extension .CII. The intent of this interface is to allow users access to any particular data item from an _A input file, to enable a complete _A file to be built from a CAD program, and to allow CAESAR II input data to be used for other analysis purposes. Users implementing this interface should be warned that the content and format described in this section is subject to change, as a function of the enhancements made to the CAESAR II program. Every effort will be made to keep such “drastic” changes to a minimum. The CAESAR II neutral file, henceforth referred to as the .CII file, is divided into sections which organize the piping data in logical groupings. Each major section is discussed below. Details of each item are discussed to the right of the page. Section divisions are denoted in the neutral file by the ‘#$’ character sequence found in columns 1 & 2. The token following the ‘#$’ character sequence is a section identifier, used by the program for data sequencing purposes, and to aid the user in reading the neutral file. Several third-party CAD programs, such as AVEVA’s PDMS and Jacobus’ Plant Space also support this neutral file. For each item listed on the following pages, the necessary FORTRAN format for the input/output is provided. The following variables are used in dimensioning arrays: N1—Base memory allocation quantity, used to set array sizes. For example, if N1=2,000, your neutral file can handle up to 2,000 elements. N2—1/2 N1 N3—1/3 N1 N4—1/4 N1 N5—1/5 N1 N6—N1/13.33

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75

Version and Job Title Information #$ VERSION. This is the section division header. The #$ and space are required, as well as the word VERSION, all in capital letters. Use FORTRAN format (2X, 4G13.6) to write the values of the following variables on the first line of the neutral file: GVERSION is the version of the neutral file interface being used. This corresponds to the major version number of CAESAR II, i.e. 4 for 4.x. RVERSION is the specific CAESAR II version generating this file, i.e. 4.50. SPARE are unused (at this time) locations on the record. The next 60 lines of 75 characters each are reserved for the CAESAR II title-page text. Use FORTRAN format (2X, A75). The last line of the job title array, if found to be blank, is set by this transfer program. The text that is set here indicates that the file was created by this interface.

Control Information #$ CONTROL. This is the section division header. The #$ and space are required, as well as the word CONTROL, in capital letters. Use FORTRAN format (2X, 4I13) to write the values of the following variables on the next line of the neutral file: NUMELT is the number of piping elements (spreadsheets) in the input file. NUMNOZ is the number of nozzles in the input file. NOHGRS is the number of spring hangers in the input file. NONAM is the number of Node Name data blocks in the input file. NORED is the number of reducers in the input file. Next, write 11-members of the array (IAUXAU) that contains the number of auxiliary data types used in the input file, followed by the vertical axis indicator. Use FORTRAN format (2X, 6I13). These 11 values from the IAUXAU array are the following: 1

The number of bend auxiliary data blocks in the input file.

2

The number of rigid-element auxiliary data blocks in the input file.

3

The number of expansion-joint auxiliary data blocks in the input file.

4

The number of restraint auxiliary data blocks in the input file.

5

The number of displacement auxiliary data blocks in the input file.

6

The number of force/moment auxiliary data blocks in the input file.

7

The number of uniform-load auxiliary data blocks in the input file.

8

The number of wind-load auxiliary data blocks in the input file.

9

The number of element-offset auxiliary data blocks in the input file.

10 The number of allowable-stress auxiliary data blocks in the input file.

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11 The number of intersection auxiliary data blocks in the input file. IZUP flag. Equal to 0 for the global -Y axis vertical, equal to 1 for the global -Z axis vertical.

Basic Element Data #$ ELEMENTS. This is the section division header. The #$ and space are required, as well as the word ELEMENTS, all in capital letters. This section of the file contains integer and real data for each element in the input file. The data are organized as such: 1

real values for element “i”

2

integer values for element “i”

3

real values for element “i+1”

4

integer values for element “i+1”

These real and integer values are stored in arrays, described as follows: A 36-member array (REL) contains the real basic-element data. The REL array is dimensioned (N1,36). Use FORTRAN format (2X, 6G13.6) to write the values of the following 36 items on the appropriate six lines of the neutral file. 1

FROM node number

2

TO node number

3

Delta X

4

Delta Y

5

Delta Z

6

Diameter (value stored here is actual OD)

7

Wall Thickness (actual)

8

Insulation Thickness

9

Corrosion Allowance

10 Thermal Expansion Coefficient #1 (or Temperature #1) 11 Thermal Expansion Coefficient #2 (or Temperature #2) 12 Thermal Expansion Coefficient #3 (or Temperature #3) 13 Thermal Expansion Coefficient #4 (or Temperature #4) 14 Thermal Expansion Coefficient #5 (or Temperature #5) 15 Thermal Expansion Coefficient #6 (or Temperature #6) 16 Thermal Expansion Coefficient #7 (or Temperature #7) 17 Thermal Expansion Coefficient #8 (or Temperature #8) 18 Thermal Expansion Coefficient #9 (or Temperature #9) 19 Pressure #1 20 Pressure #2

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21 Pressure #3 22 Pressure #4 23 Pressure #5 24 Pressure #6 25 Pressure #7 26 Pressure #8 27 Pressure #9 28 Elastic Modulus 29 Poisson’s Ratio 30 Pipe Density 31 Insulation Density 32 Fluid Density 33 Plus Mill Tolerance 34 Minus Mill Tolerance 35 Seam Weld (1=Yes, 0=No) 36 Hydro Pressure Non-specified real values are assigned a value of 0.0 by this interface. If the delta coordinates are not specified, they default to zero. If the To/From fields are not specified, it is considered an error. A 18-member array (IEL) contains the pointers to the auxiliary data arrays. The IEL array is dimensioned (N1,18). NOTE, at this time, only 13 of the members of this array are utilized! Use FORTRAN format (2X, 6I13) to write the values of the following 13 items on the next two lines of the neutral file. 1

Pointer to Bend Auxiliary field. This indicates where in the bend auxiliary array the bend data for the current element can be found.

2

Pointer to Rigid Element Auxiliary field.

3

Pointer to Expansion Joint Auxiliary field.

4

Pointer to Restraint Auxiliary field.

5

Pointer to Displacement Auxiliary field.

6

Pointer to Force/Moment Auxiliary field.

7

Pointer to Uniform Load Auxiliary field.

8

Pointer to Wind Load Auxiliary field.

9

Pointer to Element Offset Auxiliary field.

10 Pointer to Allowable Stress Auxiliary field. 11 Pointer to Intersection Auxiliary field.

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12 Pointer to Node Name Auxiliary field. 13 Pointer to Reducer Auxiliary field.

A pointer value of zero should be used where there is no auxiliary data of a particular type associated with the current element.

Auxiliary Element Data #$ AUX_DATA. This is the section division header. The #$ and space are required, as well as the word AUX_DATA, all in capital letters. This section of the file contains the auxiliary data corresponding to the elements. This data is arranged in the same order as the IAUXAU array described previously. For example, if IAUXAU(1) contains a 3, then there are 3 bends in the model, and their data is found next in the neutral file. Also assume that IAUXAU(2) contains a 5, then there are 5 rigid elements in the model and their data follows the bend data. Each set of auxiliary data is separated by a sub-section header. If a particular value in IAUXAU is zero, then only the subsection header is written to the neutral file. The data storage for these arrays is allocated at run time, based on the available free system memory. These arrays are allocated proportionally, as a percentage of the number of elements allowed. Four proportions are used: 1/2, 1/3, 1/4, and 1/5. These proportions correspond to the variables: N2, N3, N4, and N5. Maintaining these proportions ensures that the neutral file reader can accept the file. #$ NODENAME. This is the subsection header that defines the start of Node Name data. (In order to maintain downward compatibility, this section is optional.) The data for each element set of node names in the input file is listed here. A two-member array (NAM) defines each set of node names. The NAM array is dimensioned (N6, 2). Use FORTRAN format (2X, A10, 16X, A10) to read first the character name of the FROM node and then that of the TO node. #$ BEND. This is the subsection header that defines the start of the bend data. The data for each bend in the input file is listed here. An 11-member array (BND) defines each bend. The BND array is dimensioned (N3,11). Use FORTRAN format (2X, 6G13.6) to write the values of the following 11 items on the next two lines of the neutral file. 1

bend radius

2

type: 1 - single flange 2 - double flange 0 or blank - welded

3

angle to node position #1

4

node number at position #1

5

angle to node position #2

6

node number at position #2

7

angle to node position #3

8

node number at position #3

9

number of miter cuts

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10 fitting thickness of bend if different from the pipe 11 Seam Weld (1=Yes, 0=No) #$ RIGID. This is the subsection header that defines the start of the rigid data. The data for each rigid in the input file is listed here. A single-element array (RIG) for each rigid. The RIG array is dimensioned (N3,1). The single element of the array represents the rigid weight. Use FORTRAN format (2X, 6G13.6) to write the value. #$ EXPJT. This is the subsection header that defines the start of the expansion joint data. The data for each expansion joint in the input file is listed here. The EXP array is dimensioned (N5,5). Use FORTRAN format (2X, 6G13.6) to write the values of the following five items on the next line of the neutral file. 1

axial stiffness

2

transverse stiffness

3

bending stiffness

4

torsional stiffness

5

effective inside bellows diameter

#$ RESTRANT. This is the subsection header that defines the start of the restraint data. The data for each restraint auxiliary data block in the input file is listed here. The RES array is dimensioned (N2,36). Use FORTRAN format (2X, 6G13.6) to write the values of the following nine items on the next two lines of the neutral file. These nine items are repeated four times for the four possible restraints defined in the auxiliary data block. This will require two lines in the neutral file for each restraint specification, which means eight lines total for each restraint auxiliary. 1

restraint node number

2

restraint type (see additional notes to follow)

3

restraint stiffness

4

restraint gap

5

restraint friction coefficient

6

restraint connecting node

7

X direction cosine

8

Y direction cosine

9

Z direction cosine

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Note:

Items 3-9 may change based on the value of the restraint type. See the help text for details on this.

The restraint type is an integer value whose valid range is from 1 to 62. The 62 possible restraint types are

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81

#$ DISPLMNT. This is the subsection header that defines the start of the displacement data. The data for each displacement auxiliary data block in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following 55 items on the next lines of the neutral file. The DIS array is dimensioned (N3,110). This will require ten lines in the neutral file for each displacement specification, which means 20 lines total for each displacement auxiliary.

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These 55 items are repeated 2 times for the two possible displacements defined on the auxiliary. Note: Unspecified displacement values (i.e., free-displacement degrees of freedom) are designated through the use of a value of 9999.99. #$ FORCMNT. This is the subsection header that defines the start of the force/moment data. The data for each force/moment auxiliary data block in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following 55 items on the next ten lines of the neutral file. The FOR array is dimensioned (N3,38). This will require ten lines in the neutral file for each force/moment specification, which means 20 lines total for each force/moment auxiliary data block.

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#$ UNIFORM. This is the subsection header that defines the start of the uniform load data. The data for each uniform load in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following 9 items on the next two lines of the neutral file. The UNI array is dimensioned (N5,9). This will require two lines in the neutral file for each uniform load auxiliary data block. {vector 1 & 2} {vector 3}

UX1

UY1 UZ1

UX3

UY3 UZ3

UX2 UY2 UZ2

#$ WIND. This is the subsection header that defines the start of the wind/wave data. The data for each wind/wave specification in the input file is listed here. The WIND array is dimensioned (N5,5). Use FORTRAN format (2X, 6G13.6) to write the set of values on the next line of the neutral file. This will require a single line in the neutral file for each wind auxiliary. The five data items on each line are as follows: 1

entry type (0.0 for Wind, 1.0 for Wave, 2.0 for Off)

2

wind shape factor or wave drag coefficient

3

wave added mass coefficient

4

wave lift coefficient

5

wave marine growth

#$ OFFSETS. This is the subsection header that defines the start of the element offset data. The data for each offset pipe in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following six items on the next line of the neutral file. The OFF array is dimensioned (N5,6). This will require a single line in the neutral file for each offset auxiliary. 1

element FROM node offset in X direction

2

element FROM node offset in Y direction

3

element FROM node offset in Z direction

4

element TO node offset in X direction

5

element TO node offset in Y direction

6

element TO node offset in Z direction

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#$ ALLOWBLS. This is the subsection header that defines the start of the allowable stress data. The data for each allowable spec in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following 108 items on the next eighteen lines of the neutral file. The ALL array is dimensioned (N5,108). This will require eighteen lines in the neutral file for each allowable auxiliary. 1

cold allowable stress

2

hot allowable for thermal case #1

3

hot allowable for thermal case #2

4

hot allowable for thermal case #3

5

code cyclic reduction factor for thermal case #1

6

code cyclic reduction factor for thermal case #2

7

code cyclic reduction factor for thermal case #3

8

Eff.

9

Sy

10 fac 11 Pmax 12 piping code id 13 hot allowable for thermal case #4 14 hot allowable for thermal case #5 15 hot allowable for thermal case #6 16 hot allowable for thermal case #7 17 hot allowable for thermal case #8 18 hot allowable for thermal case #9 19 code cyclic reduction factor for thermal case #4 20 code cyclic reduction factor for thermal case #5 21 code cyclic reduction factor for thermal case #6 22 code cyclic reduction factor for thermal case #7 23 code cyclic reduction factor for thermal case #8 24 code cyclic reduction factor for thermal case #9 25 cycles for BW (butt-weld) fatigue pair #1 26 cycles for BW fatigue pair #2 27 cycles for BW fatigue pair #3 28 cycles for BW fatigue pair #4 29 cycles for BW fatigue pair #5

Chapter 8 Interfaces

30 cycles for BW fatigue pair #6 31 cycles for BW fatigue pair #7 32 cycles for BW fatigue pair #8 33 stress for BW fatigue pair #1 34 stress for BW fatigue pair #2 35 stress for BW fatigue pair #3 36 stress for BW fatigue pair #4 37 stress for BW fatigue pair #5 38 stress for BW fatigue pair #6 39 stress for BW fatigue pair #7 40 stress for BW fatigue pair #8 41 cycles for FW (fillet-weld) fatigue pair #1 42 cycles for FW fatigue pair #2 43 cycles for FW fatigue pair #3 44 cycles for FW fatigue pair #4 45 cycles for FW fatigue pair #5 46 cycles for FW fatigue pair #6 47 cycles for FW fatigue pair #7 48 cycles for FW fatigue pair #8 49 stress for FW fatigue pair #1 50 stress for FW fatigue pair #2 51 stress for FW fatigue pair #3 52 stress for FW fatigue pair #4 53 stress for FW fatigue pair #5 54 stress for FW fatigue pair #6 55 stress for FW fatigue pair #7 56 stress for FW fatigue pair #8

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Items 57 through 108 are for the TD/12 piping code.

Some of these items (notably 8-24) may have various meanings based on the active piping code. #$ SIF&TEES. This is the subsection header that defines the start of the SIF/TEE data. The data for each SIF/TEE spec in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following 30 items, for each of the two tees that can be specified on the dialog. The SIF array is dimensioned (N4,60). This will require five lines in the neutral file for each SIF/TEE specified, which means ten lines total for each auxiliary. 1

intersection node number

2

intersection type code, if not specified this auxiliary is only used to specify SIFs

3

SIF, in plane

4

SIF, out of plane

5

Weld id

6

Fillet

7

Pad thk

8

FTG Ro

9

crotch

10 weld id 11 B1 12 B2 Items 13 - 30 are for the TD/12 piping code. #$ REDUCER. This is the subsection header that defines the start of the REDUCER data. The data for each REDUCER spec in the input file is listed here. Use FORTRAN format (2X, 6G13.6) to write the values of the following 5 items on the next line of the neutral file. The RED array is dimensioned (N6,5). This will require one line in the neutral file for each REDUCER specified. 1

2nd diameter of the reducer

2

2nd thickness of the reducer

3

alpha angle of the reducer

4

R1 value of the reducer for the TD/12 piping code

5

R2 value of the reducer for the TD/12 piping code

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These values are repeated for the second intersection specification.

Miscellaneous Data Group #1 #$ MISCEL_1. This is the section division header. The #$ and space are required, as well as the word MISCEL_1, all in capital letters. The data in this group consists of the material id (RRMAT) for each element in the input file, the nozzle data (VFLEX), the hanger data, and the execution options. Material ID. The first array in this section (RRMAT) contains the material id number for each element in the input file. Use FORTRAN format (2X, 6G13.6). The RRMAT array is dimensioned (N1). The material ids range from 1 to 699 ( See the User’s Guide for details). The number of lines required to write the RRMAT array in the neutral file is determined by the following FORTRAN routine: NLINES = NUMELT / 6 IF( MOD(NUMELT,6) .NE. 0 ) THEN NLINES = NLINES + 1 ENDIF Nozzles. The next set of data describes the flexible (WRC-297, PD-5500, API 650) nozzles in the input file. Note:

9999.99 represents infinity.

Use FORTRAN format (2X, 6G13.6). The nozzle (VFLEX) contains 16 values for each nozzle in the input. This will require four lines in the neutral WRC-297, PD-5500, and/or API 650 spreadsheet. The VFLEX array is dimensioned (N6, 16).

For WRC-297 nozzles, the 16 items are 1

Nozzle Node Number

2

Vessel Node Number (optional)

3

Nozzle type indicator (-1.0101 = 297, 1.0 = 650)

4

Nozzle Outside Diameter (in.)

5

Nozzle Wall Thickness (in.)

6

Vessel Outside Diameter (in.)

7

Vessel Wall Thickness (in.)

8

Vessel Reinforcing Pad Thickness (in.)

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Spare (not used)

10 Dist. to stiffeners or head (in.) (9999.99 = ì) 11 Dist. to opposite side stiffeners or head (in.) (9999.99 = ì) 12 Vessel centerline direction vector X 13 Vessel centerline direction vector Y 14 Vessel centerline direction vector Z 15 Vessel Temperature (optional) (°F) 16 Vessel Material # (optional)(1-17)

For PD-5500 nozzles, the 16 items are 1

Nozzle Node Number

2

Vessel Node Number (optional)

3

Nozzle type indicator (2.0-5500)

4

Vessel Type (0-Cylinder, 1-Sphere)

5

Nozzle Outside Diameter (in.)

6

Vessel Outside Diameter (in.)

7

Vessel Wall Thickness (in.)

8

Vessel Reinforcing Pad Thickness (in.)

9

Spare (not used)

10 Dist. to stiffeners or head (in.) (9999.99 = ì) 11 Dist. to opposite side stiffeners or head (in.) (9999.99 = ì) 12 Vessel centerline direction vector X 13 Vessel centerline direction vector Y 14 Vessel centerline direction vector Z 15 Vessel Temperature (optional) (°F) 16 Vessel Material # (optional) (1-17)

For API 650 nozzles, the 16 items are 1

Nozzle Node Number

2

Vessel Node Number (optional)

3

Nozzle type indicator (1.0 = 650)

4

Nozzle Outside Diameter (in.)

5

Nozzle Wall Thickness (in.)

6

Vessel Outside Diameter (in.)

7

Vessel Wall Thickness (in.)

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Spare (not used)

9

Reinforcing on 1 - shell, or 2 - nozzle

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10 Height of nozzle centerline (in.) 11 Height of tank fluid (in.) 12 Not Used 13 Specific gravity of fluid 14 Thermal expansion coefficient (in/in/deg) 15 Delta Temperature (°F) 16 Elastic Modulus (psi) Hangers. The next set of data describes the spring hangers in the input file. Some of the hanger data listed below represent uninitialized data. In the instances where this uninitialized data represent infinite values (such as maximum travel limit and available space) it is reported here as 9999.99. The next line contains values for the following parameters in FORTRAN format (2X, I13, 5G13.6): IDFTABLE is the default hanger table. DEFVAR is the default for allowed load variation. DEFRIG is the default for rigid support displacement criteria. DEFMXTRAVEL is the default for maximum allowed travel. DEFSHTSPR is the default for allowing short range springs (0=no 1=yes). DEFMUL is the default multi load case design option. The next line contains values for the following parameters in FORTRAN format (2X, 5I13): IDFOPER is the default # of hanger design operating cases (always 1) IACTCLD is the default cold load calculation switch (0=no, 1=yes). IHGRLDS is the number of hanger operating loads (0 -3). IACTUAL is the load case defining actual cold loads. IMULTIOPTS is the multiple load case design option (1-7). An array of hanger node numbers (IHGRNODE) is read/written for each hanger in the input file and is dimensioned (N5). There will be seven lines in the neutral file for this data, if all N5 hangers are specified. Use FORTRAN format (2X, 6I13). A 10-element array (HGRDAT) is read/written for each hanger in the input file. The HGRDAT array is dimensioned (10,N5). Each hanger in the model will require two lines in the neutral file. Use FORTRAN format (2X, 6G13.6). 1

hanger stiffness

2

allowable load variation

3

rigid support displacement criteria

4

allowed space for hanger

5

cold load #1 (theoretical)

6

hot load #1 (initialize to 0.0)

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7

user defined operating load f/ variable springs (init to 0.0)

8

maximum allowed travel limit

9

multiple load case design option

10 hanger constant effort support load A four-element array (IHGRFREE) is read/written for each hanger in the input file. The IHGRFREE array is dimensioned ( 4,N5). Each hanger in the file will require one line in the neutral file.

Use FORTRAN format (2X, 6I13). 1

anchor node to be freed (#1)

2

anchor node to be freed (#2)

3

d.o.f. type for #1 (1-free Y, 2-free XY, 3-free ZY, 4-free X, Y, Z, 5-free all)

4

d.o.f. type for #2

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An array (IHGRNUM) lists the number of hangers at this location, for each hanger in the input file. There will be one entry here for every hanger in the file. The IHGRNUM array is dimensioned (N5). There will be seven lines in the neutral file for this data, if all N5 hangers are specified. Use FORTRAN format (2X, 6I13). An array (IHGRTABLE) listing the hanger table numbers for each hanger in the input file. There will be one entry here for every hanger in the file. The IHGRTABLE is dimensioned (N5). There will be seven lines in the neutral file for this data, if all N5 hangers are specified. Use FORTRAN format (2X, 6I13). An array of flags (IHGRSHORT) indicates if short range springs can be used at each hanger location. The IHGRSHORT array is dimensioned (N5). There will be seven lines in the neutral file for this data. Use FORTRAN format (2X, 6I13). 0 = can’t use short range springs 1 = can use short range springs An array of connecting node numbers (IHGRCN) is available for each hanger. The IHGRCN array is dimensioned (N5). There will be seven lines in the neutral file for this data, if all N5 hangers are specified. Use FORTRAN format (2X, 6I13). Execution Options. The next section of data defines the execution options used by the program. Use FORTRAN format (2X, 4I13, G13.6, I13). This will require three lines in the neutral file. These values are Print forces on rigids and expansion joints 0=no, 1=yes Print alphas & pipe props. during error checking 0=no, 1=yes Activate Bourdon Pressure Effects 0, 1, or 2 Activate Branch Error and Coordinate Prompts 0=no, 1=yes Thermal Bowing Delta Temperature degrees Use Liberal Stress Allowable 0=no, 1=yes For the following data, use FORTRAN format: (2X, I13, 2G13.6, 3I13): Uniform Load Input in g’’s 0=no, 1=yes Stress Stiffening due to Pressure 0, 1, 2 Ambient Temperature (If not 70.00 deg F ) degrees FRP Expansion * 1,000,000 len/len/deg Optimizer 0-Both, 1-CuthillMcKee, 2-Collins Next Node Selection 0-Decreasing, 1-Increasing For the following data, use FORTRAN format (2X, 4I13, G13.6, I13): Final Ordering 0-Reversed, 1-Not Reversed Collins Ordering 0-Band, 1-No. of Coefficients Degree Determination 0-Connections, 1-Band User Control 0-None, 1-Allow User Re-Looping FRP Shear ratio Laminate type

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Units Conversion Data #$ UNITS. This is the section division header. The #$ and space are required, as well as the word UNITS. The data in this section defines both the conversion constants as well as the conversion labels. The conversion constants are all REAL*4 values in FORTRAN format (2X, 6G13.6). This will require four lines in the neutral file. The following are character definitions for the labels: CNVLEN is the length conversion. CNVFOR is the force conversion. CNVMAS is the mass conversion. CNVMIN is the moment (input) conversion. CNVMOU is the moment (output) conversion. CNVSTR is the stress conversion. CNVTSC is the temperature conversion. CNVTOF is the temperature offset. CNVPRE is the pressure conversion. CNVYM is Young’s modulus conversion. CNVPDN is the pipe density conversion. CNVIDN is the insulation density conversion. CNVFDN is the fluid density conversion. CNVTSF is the translational stiffness conversion. CNVUNI is the uniform load conversion. CNVWND is the wind load conversion CNVELE is the elevation conversion CNVCLN is the compound length conversion CNVDIA is the diameter conversion CNVTHK is the wall thickness conversion Next, enter the following units’ labels, one per line, in the format given in the label descriptions. This will require 24 lines in the neutral file. CCVNAME - name of the units used, i.e. english, si, ..(CHARACTER*15) CCVNOM - “on” or “off” and tells PREPIP whether or not nominal diameters are allowed (CHARACTER* 3). CCVLEN - length label (CHARACTER* 3) CCVFOR - force label (CHARACTER* 3) CCVMAS - mass label (CHARACTER* 3) CCVMIN - moment (input) label (CHARACTER* 6) CCVMOU - moment (output) label (CHARACTER* 6) CCVSTR - stress label (CHARACTER*10)

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CCVTSC - temperature label (CHARACTER* 1) CCVTOF - temperature offset/label (CHARACTER* 1) CCVPRE - pressure label (CHARACTER*10) CCVYM - young’s modulus label (CHARACTER*10) CCVPDN - pipe density label (CHARACTER*10) CCVIDN - insulation density label (CHARACTER*10) CCVFDN - fluid density label (CHARACTER*10) CCVTSF - translational stiffness label (CHARACTER* 7) CCVRSF - rotational stiffness label (CHARACTER*10) CCVUNI - uniform load label (CHARACTER* 7) CCVGLD - gravitional load label (CHARACTER* 3) CCVWND - wind load label (CHARACTER*10) CCVELE - elevation label (CHARACTER* 3) CCVCLN - compound length label (CHARACTER* 3) CCVDIA - diameter label (CHARACTER* 3) CCVTHK - wall thickness label (CHARACTER* 3)

Nodal Coordinate Data #$ COORDS . This is the section division header. The #$ and space are required, as well as the word COORDS, all in capital letters. This section only exists in Versions 3.22 and later. The data in this section of the neutral file is optional; it may not exist. The existence of this data depends on the user’s preference and the particular job. This section of the neutral file is used to specify the X, Y, Z global coordinates of the starting node point of each discontinuous piping segment. This data, if it exists, is defined below. The NXYZ value defines how many sets of coordinates follow. Use FORTRAN format (2X, I13). INODE, XCORD, YCORD, ZCORD This line of four values is repeated NXYZ times. Use FORTRAN format (2X, I13, 3F13.4) to define a node number and its X, Y, Z global coordinates.

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Data Matrix Interface CAESAR II offers an alternative neutral file, the Data Matrix Interface. The generic CAESAR II data matrix input routine creates a CAESAR II file from a simple neutral file. It expects to read a file that contains a single line of data for each pipe in the model. Each line of data contains twelve parameters as follows: ELMT

N1

N2

DX

DY

DZ

DIAM

THK

ANCH

BEND

BRAD

RIGID

Where: ELMT is the element number, sequential from 1. N1 is the “from” node number. N2 is the “to” node number. DX is the delta dimension in the global “X” direction. DY is the delta dimension in the global “Y” direction (the “Y” axis is vertical in CAESAR II). DZ is the delta dimension in the global “Z” direction. DIAM is the actual pipe diameter. THK is the actual pipe wall thickness. ANCH is a restraint flag, 1 if the “from” node is restrained, 0 otherwise. Currently ignored. BEND is a bend indicator, 1 if the element has a bend at the “to” node, 0 otherwise. BRAD is the bend radius if not a long radius bend. Important

RIGID is a rigid element flag, 1 if the element is rigid, 0 otherwise.

All values in the matrix should be “real,” floating point numbers. The format for each line of data should be (12E13.6). This generic interface does prompt for an arbitrary conversion constant for the delta dimensions and the diameter /thickness values to overcome any differences between the assumed units of the neutral file and the CAESAR II defaults. Users developing an interface from scratch are urged to use the Complete Neutral File interface discussed in the next section. The Data Matrix Interface discussed above transfers the piping geometry only, which requires the analyst to input additional data to complete the stress model.

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Computational Interfaces LIQT Interface The CAESAR II / LIQT Transfer program is used to generate CAESAR II dynamic input data files containing response spectra for input files which contain the dynamic pipe forces. These time history loads are determined by the Stoner Associates, Inc. (SAI) LIQT package, from pressure transient loading. The CAESAR II / LIQT Transfer program reads the output file generated by LIQT, extracts the information needed, and generates the response spectra. Then, the generated response spectrum files can be used for the dynamic analysis in CAESAR II.

How to Use the CAESAR II / LIQT Interface When the user reaches the LIQT Transfer module, the following input is required from the user in order to process the LIQT data: LIQT output file name. (This file is generated by SAI’s LIQT package with extension .FRC) Names of LIQT nodes which identify the pipes that response spectra are to be generated for. Corresponding CAESAR II node numbers for the LIQT pipes. Maximum number of points on each generated response spectrum curve. Frequency cut off value. After the proper user input data is acquired, the LIQT interface module starts the data transfer. During the computation, the user will be apprised of the process status. The user can click the Cancel button at any time to abort the computation. The resulting force spectrum files (DLF curves) are written to the CAESAR II data directory during the computation phase of the program. The names of generated force spectrum files have the following format: L*.DLF where "*" is the user CAESAR II node number in the piping model which corresponds to the equivalent LIQT pipe name. When all computations have completed, the user will be returned to the CAESAR II MAIN MENU.

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Technical Discussion of LIQT Interface Normal piping system operating procedures such as pump start-up and shutdown, valve closure, and unexpected events such as power failure, may produce unsteady pressure-flow conditions. A piping system with rapid pressure-flow variations must be carefully designed to prevent devastating results. SAI’s LIQT package performs the analysis and simulation of the unsteady flow situations for a particular liquid piping system, and generates the piping load time histories for the pressure transient of this particular liquid piping system. In the dynamic analysis module of CAESAR II, a response spectrum can be generated from the user input of time history pulse. However, there are typically too many data points from a time history analysis for a user to manually input the data into CAESAR II. The CAESAR II LIQT Transfer is used to bridge the gap between SAI’s LIQT package and the CAESAR II dynamic analysis module. After the time history loads have been generated by SAI’s LIQT package, the CAESAR II LIQT interface extracts the dynamic pipe forces from the LIQT generated file, and computes the response spectrum. Afterward, the response spectrum can be used as the DLF curve for the dynamic analysis in CAESAR II. The response spectrum is a plot giving the maximum response of all possible linear one degree of freedom systems due to a given input, which in the present case is a force. The abscissa of the spectrum is the frequency axis, and the ordinate is the maximum response, i.e. the dynamic load factor (DLF). The DLF is the ratio of the dynamic deflection at any time to the deflection which would have resulted from the static application of the load. In cases where the applied load is not constant, the maximum load which occurs at any time during the period of interest is taken. The dynamic load factor is non dimensional and independent of the magnitude of load. The following examples illustrate the characteristics of the DLF curve in terms of the magnitude and the duration of the load.

Example 1 Find the DLF response spectrum of the trapezoidal pulse loads shown in the following figure.

Force vs. Time

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Solution: The response spectra generated from all four pulse loads are identical, as shown in the following figure.

DLF vs. Frequency

The result shows that the DLF curve is independent of the magnitude of the pulse load.

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Example 2 Find the response spectrum of the following trapezoidal pulse loads.

Force vs. Time

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Force vs. Time

Force vs. Time

Solution: The plotted results displayed in Figure 13.11 show that the longer the duration of the force the higher the DLF. The triangular pulse, which has a duration of zero, generates the lowest DLF curve.

DLF vs. Frequency

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PIPENET Interface The CAESAR II / PIPENET Transfer program is used to generate CAESAR II dynamic input data files containing response spectra for input files which contain the dynamic pipe forces. These time history loads are determined by the Sunrise System's Pipenet package, from pressure transient loading. The CAESAR II / PIPENET Transfer program reads the output file generated by PIPENET, extracts the information needed, and generates the response spectra. Then, the generated response spectrum files can be used for the dynamic analysis in CAESAR II.

How to Use the CAESAR II / PIPENET Interface When the user reaches the PIPENET Transfer module, the following input is required from the user in order to process the PIPENET data: PIPENET output file name. (This file is generated by Sunrise System's PIPENET package with extension .FRC) Names of PIPENET pipes whose response spectra are to be generated for. Corresponding CAESAR II node numbers for the PIPENET pipes. Maximum number of points on each generated response spectrum curve. Frequency cut off value. After the proper user input data is acquired, the PIPENET interface module starts the data transfer. During the computation, the user will be apprised of the process status. The user can press the Cancel button at any time to abort the computation. The resulting force spectrum files (DLF curves) are written to the CAESAR II data directory during the computation phase of the program. The names of generated force spectrum files have the following format: P*.DLF where "*" is the user CAESAR II node number in the piping model which corresponds to the equivalent PIPENET pipe name. Further, the PIPENET Interface creates a complete CAESAR II Dynamic Input file including spectrum definition, force sets, load cases, and combination load cases. The resulting input file is ready to be run "as is" or can be further modified by the user. When all computations have completed, the user will be returned to the CAESAR II Main Menu.

Technical Discussion of PIPENET Interface Normal piping system operating procedures such as pump start-up and shutdown, valve closure, and unexpected events such as power failure, may produce unsteady pressure-flow conditions. A piping system with rapid pressure-flow variations must be carefully designed to prevent devastating results. The PIPENET package performs the analysis and simulation of the unsteady flow situations for a particular liquid piping system, and generates the piping load time histories for the pressure transient of this particular liquid piping system. In the dynamic analysis module of CAESAR II, a response spectrum can be generated from the user input of time history pulse. However, there are typically too many data points from a time history analysis for a user to manually input the data into CAESAR II. The CAESAR II PIPENET Transfer is used to bridge the gap between PIPENET and the CAESAR II dynamic analysis module.

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After the time history loads have been generated by PIPENET, the CAESAR II PIPENET interface extracts the dynamic pipe forces from the PIPENET generated file, and computes the response spectrum. Afterward, the response spectrum can be used as the DLF curve for the dynamic analysis in CAESAR II. The response spectrum is a plot giving the maximum response of all possible linear one degree of freedom systems due to a given input, which in the present case is a force. The abscissa of the spectrum is the frequency axis, and the ordinate is the maximum response, i.e. the dynamic load factor (DLF). The DLF is the ratio of the dynamic deflection at any time to the deflection which would have resulted from the static application of the load. In cases where the applied load is not constant, the maximum load which occurs at any time during the period of interest is taken. The dynamic load factor is non dimensional and independent of the magnitude of load. The following examples illustrate the characteristics of the DLF curve in terms of the magnitude and the duration of the load.

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Data Export to ODBC Compliant Databases CAESAR II permits the export of the analysis results to ODBC compliant databases. ODBC is a programming interface that enables applications to access data in database management systems that use Structured Query Language (SQL) as a data access standard. CAESAR II uses two drivers supplied by Microsoft Corporation to communicate with the Access database or Excel spreadsheet. These drivers are installed by default when either of the two products are set up on a system.

DSN Setup In order to use the CAESAR II data export facility, you need to set up two Data Source Names (DSNs) on the system. DSNs contain information regarding where the database resides on the computer and how to communicate with it, i.e. what driver to use. CAESAR II has capabilities to export data to either an Access database or an Excel spreadsheet. Therefore, you will need two DSNs set up to allow use of this feature. The names of these two DSNs are FIXED by COADE Inc. The CAESAR II installation program is designed to set up these DSNs automatically. However, in the event that the DSNs are not set up, use the procedure listed below.

Setting up the DSN: 1

Click the Start button and select Settings and then Control Panel.

2

Double-click on ODBC Data Sources icon and select the User DSN tab.

3

Click the Add button. A window similar to the following will display.

Create New Data Source Important Follow steps 4 through 8 for Microsoft Access DSN Setup ONLY! Skip to step 9 for Microsoft Excel DSN Setup

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Select the Microsoft Access Driver (*.mdb) and click the Finish button. A window similar to the one below will display and you will be prompted to select your database.

Access DSN Setup The data source name MUST be the C2_OUT_ACCESS. The description is an optional field and can hold any description information. 5

Enter the Data Source Name and the Description, and click the Select button to select the CAESAR II template database.

CAESAR II is supplied with a template database that contains the structure to hold data exported from the program. For Access: this file is named “caesarII.mdb” and will be present in the “system” directory of your CAESAR II installation directory. 6

Select the file and click the OK button as shown in the following figure.

Select Database Window

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After completing the previous step, you will be returned to the ODBC Microsoft Access Setup window similar to the following figure.

Access Setup Screen After Database Selection 7

Click the OK button and a window similar to the one below will be displayed. Note that C2_OUT_ACCESS has been added to list of available user DSN’s.

User DSN Tab After Adding Access DSN You have now completed the Access DSN setup.

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This above process needs to be performed only once per machine.

Controlling the Data Export The CAESAR II data export is controlled using the Setup/Configuration module. By default, data export is disabled. You must run Configure/Setup to enable ODBC data export. To set up the ODBC data export in CAESAR II, follow the steps below.

Setting up the ODBC data export 1

Select CONFIGURE/SETUP on the Tools pull-down menu from the CAESAR II Main Menu.

2

Select the Database Definitions tab.

3

Check the Enable data export to ODBC compliant databases check box, which will enable the Browse button.

4

Click the Browse button, type the name of your database and save it in a directory of your choice.

Note: CAESAR II will copy the template database to the directory specified and name the database as specified. The Append re-runs to existing data check box is optional. If left unchecked, re-runs of the same job will overwrite any existing data for the same job in the database/spreadsheet. If checked, re-runs will add or append data from the new runs to the database/spreadsheet. 5

Click Exit w/ Save to save changes to the configuration.

Note: As in previous versions of CAESAR II, the configuration file applies to all CAESAR II jobs present in that directory. Similarly, the external database/spreadsheet specified in one configuration file applies to all jobs present in that directory.

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Data Export Wizard CAESAR II offers an ODBC Wizard for immediate interfacing (in addition to the in-line interfacing offered previously) of both input and output piping model data. (Note that the input data may only be accessed through the Wizard; while the in-line interface still transfers only the output data.) This wizard, besides being compatible with ODBC (Microsoft Access and Excel) can also export data in XML format. (Note that the Excel interface produces a semicolon delimited text file, which can be imported into Excel very quickly.) The interface is accessed via the Tools/Eternal Interfaces/Data Export Wizard menu command from the CAESAR II Main Menu. The Data Export Wizard dialog displays; the exported data set can be developed by responding to the questions and clicking the Next button.

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The Input and Output Files dialog requests the name of the CAESAR II piping file (the._A file) for which the data is to be exported: the user must browse for it.

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Activating the Export Output Data Also check box provides the ability to include any output results (if available) to the exported data set as well. Activating the Use System Units check box converts the data to the set of units currently selected in the CAESAR II Configure /Setup. Selection of the Data Export Output file designates where the data will go, as well as in what form the data will be: selection of files with extensions of .MDB, .TXT, or .XML produce data in the form of Microsoft Access™, Microsoft Excel™ semi-colon delimited text, or XML, respectively.) Note, a great deal of on-line help is provided for this wizard, accessible via the Help button. The CAESAR II Input Export Options dialog allows the user to select the input data items that are to be exported.

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If the user has clicked the Export Output Data check box, the CAESAR II Output Export Options dialog allows the user to select the type of results to be exported, and the load cases for which these results are to be exported.

Clicking finish completes the operation. The resultant data file may now be queried or otherwise manipulated through the use of Microsoft Access, Microsoft Excel, or XML parsing software. Note that a number of built in reports, queries, and other helpful items (see the figure above) have been provided in the default Access file format, or the user can develop custom reports and queries.

1

CHAPTER 9

File Sets In This Chapter CAESAR II File Guide................................................................2 CAESAR II Operational (Job) Data Files ...................................14

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CAESAR II File Guide CAESAR II is composed of a number of files which are loaded onto the hard drive. At the current time, approximately 60 megabytes are required for a complete software installation. If your disk is “cramped” for space, you may have to manually delete files from your hard disk before installing a new version of CAESAR II. If you are storing data files in your CAESAR II installation directory, archive them first before you begin the file deletion process. If you are performing a partial installation, be sure the directory is clean before you start; otherwise you will have a mixed version and it will not perform as expected, and CRC errors may be generated during the installation. If you have adequate space on your hard drive, the new program data files will overwrite the existing data files from the previous version. Some exceptions, such as the material database file, change from year to year, and may have to be deleted manually to maximize disk space. After a successful installation, the following directory structure will exist on the hard disk, assuming the installation directory was named "caesar."

\caesar

contains main program files

\caesar\acrobat

contains the Adobe Acrobat Reader installation file

\caesar\assidrv

contains HASP device drivers and instructions

\caesar\c2_docu

contains the CAESAR II on-line documentation

\caesar\examples

contains example jobs

\caesar\lib_i

contains CADWorx library file in Imperial units

\caesar\lib_m

contains CADWorx library file in Metric units

\caesar\setupesl

contains ESL device driver installation routine

\caesar\Spec

contains CADWorx specification files

\caesar\ssidrv

contains SSI device drivers and instructions

\caesar\system

contains program data file templates and libraries

It should be noted that as a disk reaches its capacity, disk access can be slowed considerably. For this reason it is a good idea to perform some periodic “house cleaning” on the directory(s) where CAESAR II files are stored. This would involve deleting scratch files and old job files. The CAESAR II File-Clean Up Files command option can help in this process.

Chapter 9 File Sets

Required for Execution

Description

ANAHLP01.EXE

Help file for dynamic input and load case editor

ANAHLP02.EXE

Help file for dynamic input and load case editor

ANAL1.EXE

Static load cases/Dynamic input program

ANNOUNCE.EXE

Build changes announcement program

C2.EXE

Main Menu program

C2DATA.EXE

Input conversion to new units program

C2HELP01.EXE

Help file

C2HELP02.EXE

Help index

C2SET01.EXE

Help file

C2SET02.EXE

Help index

C2SETUP.EXE

Configuration program

C2U.EXE

Buried pipe modeler

CRCCHK.EXE

CRC check program

ELEM.EXE

Element generator

ENGLISH.FIL

English units file

EXPJT.HED

Generic expansion joint header file

FRP.HED

Generic FRP header file

IECHO.EXE

Input echo setup/Neutral file program

INCORE.EXE

In-core solution module program

M1HELP01.EXE

Miscellaneous help file

M1HELP02.EXE

Miscellaneous help file

OP2HLP01.EXE

Output processor help file

OP2HLP02.EXE

Output processor help file

MM.FIL

Millimeter units file

OUTCORE.EXE

Out-of-core solution module program

OUTP01.EXE

Static force/stress computation program

OUTP02.EXE

Static output processor

PIERCK.EXE

Piping error checker

PREPIP.EXE

Piping input module

REPORT.EXE

Input list/echo generation program

SI.FIL

SI units file

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Required for Execution

Description

STREAM.EXE

Batch stream processor program

SYSCHK.EXE

System check out program

TIPS.TXT

Start-up Tip-of-the-Day program

TYPE.BIN

Parameter definition file

VALVE.HED

Generic valve/flange header file

XX.CRC

CRC check data file

Required Error Data Files

Description

C2ER01A.EXE

Error explanation text

C2ER01B.EXE

Error index file

C2ER01C.EXE

Error explanation text

C2ER01D.EXE

Error index file

C2ER01E.EXE

Error explanation text

C2ER01F.EXE

Error index file

C2ER01Z.EXE

Error explanation text

C2ER02A.EXE

Error index file

C2ER02B.EXE

Error explanation text

C2ER02C.EXE

Error index file

C2ER02D.EXE

Error explanation text

C2ER02E.EXE

Error index file

C2ER02F.EXE

Error explanation text

C2ER02Z.EXE

Error index file

C2ERROR.EXE

Error reporting program

Required Data Set

Description

5-110-1A.FAT

Material fatigue curve

5-110-1B.FAT

Material fatigue curve

5-110-2A.FAT

Material fatigue curve

Chapter 9 File Sets

Required Data Set

Description

5-110-2B.FAT

Material fatigue curve

5-110-2C.FAT

Material fatigue curve

ACCESS2K.BAT

Batch file to switch to Access 2000

ACCESS97.BAT

Batch file to switch to Access 97

AMRN2020.FRP

FRP data

AP.BIN

ANSI pipe sizes

API650.DIG

API650 chart data

APPRVD.BIN

Stoomwezen approval certificate

BE.HGR

Basic engineering hanger data

BERGEN.HGR

Bergen Power hanger data

BHEL.HGR

BHEL hanger data

C2MAT.EXE

Material database editor

CAESAR.FRP

FRP data

CAESARII.MDB

Access template file

CAESARI1997I.MDB

Access 97 database template

CAESARII2000.MDB

Access 2000 database template

CAESARII.XLS

Excel template file

CAPITOL.HGR

Capitol hanger data

CARPAT.HGR

Carpenter & Paterson hanger data

CHINAPWR.HGR

China Power hanger data

CMAT.BIN

Supplied Material database

CMP_INP.BAT

Batch file for compressed input listing

COL_INP.BAT

Batch file for column oriented input listings

COMET.HGR

Comet Hanger data

CRANE.DAT

Crane valve/flange database

CRANE.VHD

Crane valve/flange header file

DP.BIN

DIN pipe sizes

ENGLISH.FIL

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Required Data Set

Description

FLEXIDIR.HGR

Flexidir hanger data

FLEXPATH.DAT

Flexonics/Pathway Bellows expansion joint database

FLEXPATH.JHD

Flexonics/Pathway Bellows header file

FRONEK.HGR

Fronek hanger data

GENERIC.DAT

Generic valve/flange database

GENERIC.VHD

Generic valve/flange header file

GRINNELL.HGR

Grinnell hanger data

HYDRA.HGR

Hyrda hanger data

HYDRAANG.DAT

HYDRA angular expansion joint database

HYDRAANG.JHD

HYDRA angular expansion joint header file

HYDRAAXI.DAT

HYDRA axial expansion joint database

HYDRAAXI.JHD

HYDRA axial expansion joint header file

HYDRALAT.DAT

HYDRA lateral expansion joint database

HYDRALAT.JHD

HYDRA lateral expansion joint header file

INOFLEX.HGR IWK_ANG.DAT

IWK angular expansion joint database

IWK_ANG.JHD

IWK angular expansion joint header file

IWK_AXI.DAT

IWK axial expansion joint database

IWK_AXI.JHD

IWK axial expansion joint header file

IWK_LAT.DAT

IWK lateral expansion joint database

IWK_LAT.JHD

IWK lateral expansion joint header file

JP.BIN

JIS pipe sizes

LISEGA.HGR

Lisega Hanger data

MATFIL1.BIN

ASME Sect VIII material database

MM.FIL MYATT.HGR

Myatt Hanger data

MYRICKS.HGR

Myricks Hanger data

NOFLANGE.DAT

Valve/flange database (no flanges)

Chapter 9 File Sets

Required Data Set

Description

NOFLANGE.VHD

Valve/flange header file (no flanges)

NPS.HGR

NPS Hanger data

OUTPUT.HED PDS_MAT.MAP

Intergraph PDS material mapping file

PDS_PIPES_CSV

Intergraph PDS pipe sizes

POWER.HGR

Power Piping Hanger data

PRINTER.FMT

Printer Formatting string file

PSC.HGR

PSC Hanger data

PSU.HGR

Pipe Supports USA data

PTP.HGR

PTP Hanger data

PTP-LRG.DAT PTP-LRG.JHD PTP-SML.DAT PTP-SML.JHD QUALITY. HGR

Quality Pipe Supports data

REGISTERPIPE.BAT

Batch file to register PIPEDLL.DLL

SARATHI.HGR

Sarathi database

SFI-MID.JHD

Senior Flexonics expansion joint database header file

SFI-MID.DAT

Senior Flexonics expansion joint database

SI.FIL SINOPEC.HGR

Sinopec Hanger data

TD12AL.FAT

Material fatigue curve

TD12ST.FAT

Material fatigue curve

TITLE.HED WAVIN55.FRP

Fiberglass material data file

WAVIN63.FRP

Fiberglass material data file

WAVIN73.FRP

Fiberglass material data file

WORD.BAS

MS Word script/formatting file

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Required Data Set

Description

WORDNOPAGESETUP.BAT Batch file to switch MS Word templates WORDNPS.BAS

MS Word script/formatting file

WORDPAGESETUP.BAT

Batch file to switch MS Word templates

WORDPS.BAS

MS Word script/formatting file

Required Printer/ Listing Files Description LIST.CRC

CRC check data file

OUTPUT.HED

Dynamic output report headers

TITLE.HED

Piping input title page template

SCREEN.TXT

Piping input resource file

ALLOW.INP

Compressed formatting for allowable stresses

ALLWTD.INP

Formatting for TD/12 allowables

API650.INP

Formatting for API 650

API6502.INP

Alternate formatting for API 650 nozzles

BENDS.INP

Compressed formatting for bends

PD5500.INP

Formatting for PD5500 nozzles

PD55002.INP

Alternate formatting for PD5500 nozzles

CONPARM.INP

Compressed formatting for control parameters

COORDS.INP

Compressed formatting for coordinates

DISPLACE.INP

Compressed formatting for displacements

ELEMENT.INP

Compressed formatting for elements, layout 1

ELEMENT0.INP

Compressed formatting for elements, layout 2

ELEMENT1.INP

Compressed formatting for elements, layout 3

ELEMENT2.INP

Compressed formatting for elements, layout 4

ELEMENT3.INP

Compressed formatting for elements, layout 5

ELEMTD12.INP

Element formatting for TD/12

Chapter 9 File Sets

Required Printer/ Listing Files Description EXPJTS.INP

Compressed formatting for expansion joints

FORCES.INP

Compressed formatting for forces

Required Printer/Listing Files

Description (continued)

HANGERS.INP

Compressed formatting for spring hangers

INITIAL.INP

Listing setup

MATERIAL.INP

Compressed formatting for materials

MAT_FRP.INP NOZZLES.INP

Compressed formatting for nozzles

OFFSETS.INP

Compressed formatting for offsets

RIGIDS.INP

Compressed formatting for rigid elements

RIGIDS2.INP

Alternate formatting for rigids

SETUP.INP

Compressed formatting for setup parameters

SIF&TEE.INP

Compressed formatting for SIFs & tees

SIF&TD12.INP SUPPORTS.INP

Compressed formatting for restraints

TITLE.INP

Compressed formatting for title page

UNIFORM.INP

Compressed formatting for uniform loads

UNITS.INP

Compressed formatting for units

WIND.INP

Compressed formatting for wind shape factors

ALLOW2.INP

Column oriented formatting for allowable stresses

BENDS2.INP

Column oriented formatting for bends

DISPLAC2.INP

Column oriented formatting for displacements

ELEMENT4.INP

Column oriented formatting for elements

EXPJTS2.INP

Column oriented formatting for expansion joints

FORCES2.INP

Column oriented formatting for forces

HANGERS2.INP

Column oriented formatting for spring hangers

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Required Printer/ Listing Files Description MATRIAL2.INP

Column oriented formatting for materials

NOZZLES2.INP

Column oriented formatting for nozzles

OFFSETS2.INP

Column oriented formatting for offsets

RIGIDS2.INP

Column oriented formatting for rigid elements

SIF&TEE2.INP

Column oriented formatting for SIFs & tees

SUPPORT2.INP

Column oriented formatting for restraints

UNIFORM2.INP

Column oriented formatting for uniform loads

WIND2.INP

Column oriented formatting for wind shape factors

Dynamics

Description

DYN.EXE

Dynamic setup/Harmonic Solution

DYNHEAD.BIN

Dynamic input screen data

DYNOUT1.EXE

Dynamic force/stress computation program

DYNOUT2.EXE

Dynamic output reporting program

DYNPLOT.EXE

Graphics animation program

DYNSTART.BIN

Dynamic input example data

EIGEN.EXE

Eigen solution program

Auxiliary Set

Description

ACCTNG.EXE

Accounting report generator

BIGPRT.EXE

Large print program

C2_MAT.EXE

Material database editor

COADEXE.EXE

EXE file scanner

DLLVBASE.TXT

DLL baseline information

DLLVERSN.EXE

DLL version scanner

Chapter 9 File Sets

Auxiliary Set

Description

DLLVERSN.LST

DLL data list

HLPROT1.EXE

Help file

HLPROT2.EXE

Help file index

MAKEUNIT.EXE

Units generation program

MATDAT.92

ASME material database

MISC.EXE

SIF, WRC297, B31G, Flange program

MISC01.EXE

Help file

MISC02.EXE

Help file index

NETUSER.BAT ROT.EXE

Equipment analysis program

RUN107.EXE

WRC107 program

UCS66.BIN

ASME UCS-66 chart data

WRC-2.DIG

WRC107 chart data

Structural Data

Description

AISC.EXE

AISC unit check program

AISC77.BIN

1977 AISC steel database

AISC89.BIN

1989 AISC steel database

AISCHLP.HLP

AISC program help file

AISCHLP.PTR

Help index file

AUST90.BIN

1990 Australian steel database

C2S.EXE

Structural input program

C2SHL01.EXE

Help file for structural input

C2SHL02P.EXE

Help file for structural input

GERM91.BIN

1991 German steel database

HELPSTR.HLP

Help file for structural input

KOREAN.BIN

1990 Korean structural database

SAFRICA.BIN

1990 South African structural database

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Structural Data

Description

UK.BIN

United Kingdom structural database

External Interfaces

Description

ACADX.EXE

AutoCad DXF generator

ADEV.EXE

PRO-ISO interface

APLANT.EXE

Autoplant interface

C2CATIA.EXE

CCPLANT/CATIA interface

C2DATIN.EXE

Generic neutral file interface

C2DXF.DAT

AutoCad DXF template file

C2LIQT.EXE

LIQT interface

C2PIPNET.EXE

PIPENET interface

CADPIP.EXE

CADPIPE interface

CVISON.EXE

ComputerVision interface

DATAEXP.CHM

Data export wizard help file

DATAEXP.EXE

Data export wizard

INTGRPH.EXE

Intergraph interface

ISOMET.EXE

Isomet interface

NODSIZ.LSP

Autocad node display routine

PCF.EXE

PCF interface

PCFDLL.DLL

Supporting DLL for PCF interface

PIPEDLL.DLL

Supporting DLL for PCF interface

Examples

Description

45-75

DLF file for HAMMER job

90-110

DLF file for HAMMER job

CRYISM._7

Dynamic input example

Chapter 9 File Sets

Examples

Description

CRYISM._A

Dynamic input example

CRYISM._J

static load case data

CRYNOS._7

Dynamic input example

CRYNOS._A

Dynamic input example

CRYNOS._J

static load case data

CRYSTR.STR

Structural input for CRYISM job

FRAME.J

static load case data

FRAME.STR

Structural input example

HAMMER._7

Dynamic input example

HAMMER._A

Dynamic input example

HAMMER._J

static load case data

JACKET._A

Jacketed pipe example input

JACKET._J

static load case data

NUREG9._7

Dynamic input example, NRC benchmark

NUREG9._A

Dynamic input example, NRC benchmark

NUREG9._J

static load case data

OMEGA._A

Omega loop example input

OMEGA._J

static load case data

RELIEF

DLF file for RELIEF job

RELIEF._7

Dynamic input example,

RELIEF._A

Relief Valve example input

RELIEF._J

static load case data

TABLE._7

Dynamic input example, harmonic

TABLE._A

Dynamic input example, harmonic

TABLE._J

Dynamic input example, harmonic

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CAESAR II Operational (Job) Data Files During the input / analysis/ output phases of operation, CAESAR II creates a number of job specific data files. Some of these data files are used solely by CAESAR II, others contain input data, and others contain output data. This section defines the commonly encountered files, their purpose, and whether or not they are important for archiving purposes. In the list below, an asterisk (*) by the file name indicates it should be saved in order to archive the input data. A double asterisk (**) indicates the file should be saved to archive output data.

INPUT, Static ._A *

Contains the User’s spreadsheet input data.

._J *

Contains the load case data.

INPUT, Dynamic ._7 *

Contains the User’s dynamic input data.

INPUT, Structural .STR *

Contains the User’s structural input data.

INPUT, Soil .SOI *

Contains the User’s soil property data.

Scratch ._B

Nodal boundary condition file, created by the piping error checker and used by the analysis modules.

._C

Element properties file, created by the piping error checker and used by the analysis modules.

._N

Nodal coordinate file, created by the piping error checker and used by the analysis modules.

._R

Job control information, created by the piping error checker and used by the analysis modules.

._E

Element connectivity file, created by the piping error checker and used by the analysis modules.

._X

Structural geometry file for use with piping preprocessor.

._1

Scratch file

._2

Scratch file

._5

Scratch file with intermediate hanger data

._6

Scratch file

.DXF

Geometric data file created for input into AUTOCAD

.HAR

Harmonic components for animation

.FRQ

Harmonic solution frequency & phase data

._L

Intermediate harmonic data file

Chapter 9 File Sets

.XYT

15

Animation output data file from time history analysis

Listing .MSG

Secondary output file with intermediate computation data

.LST

Data listing file

.LIS

Data listing file

.C2U

Buried modeler error check file

Output ._M **

Intermediate output file, contains data generated by the piping error checker and load case setup modules

._P **

Static output data file

._Q **

Actual harmonic displacement data

._S **

Dynamic output data file

._T **

Time history output data file

.OUT

User generated output (text) data file

.VAL

Intermediate eigenvalue output file

.VEC

Intermediate eigenvector output file

.OTL **

Input/Output QA sequencing data file

Note: All of these files may not be present for a given job. The presence of a file is dependent on what analysis has been run.

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CHAPTER 10

Update History The following lists detail the addition and modifications made to CAESAR II by version number. These lists correspond to the major releases of the software and do not reflect items such as: minor releases (1.0P, 2.1D); re-publication of the User Guide: or additional new modules released to aid users between updates.

In This Chapter CAESAR II Initial Capabilities (12/84) ......................................2 CAESAR II Version 1.1S Features (2/86)...................................3 CAESAR II Version 2.0A Features (10/86) ................................4 CAESAR II Version 2.1C Features (6/87) ..................................5 CAESAR II Version 2.2B Features (9/88) ..................................6 CAESAR II Version 3.0 Features (4/90).....................................7 CAESAR II Version 3.1 Features (11/90)...................................8 CAESAR II Version 3.15 Features (9/91)...................................9 CAESAR II Version 3.16 Features (12/91).................................10 CAESAR II Version 3.17 Features (3/92)...................................11 CAESAR II Version 3.18 Features (9/92)...................................12 CAESAR II Version 3.19 Features (3/93)...................................14 CAESAR II Version 3.20 Features (10/93).................................15 CAESAR II Version 3.21 Changes and Enhancements (7/94) ....16 CAESAR II Version 3.22 Changes & Enhancements (4/95).......18 CAESAR II Version 3.23 Changes (3/96)...................................20 CAESAR II Version 3.24 Changes & Enhancements (3/97).......21 CAESAR II Version 4.00 Changes and Enhancements (1/98) ....24 CAESAR II Version 4.10 Changes and Enhancements (1/99) ....25 CAESAR II Version 4.20 Changes and Enhancements (2/00) ....26 CAESAR II Version 4.30 Changes and Enhancements (3/01) ....27 CAESAR II Version 4.40 Features .............................................28 CAESAR II Version 4.40 Technical Changes and Enhancements ( 5/02)

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CAESAR II Initial Capabilities (12/84) Input data spreadsheets featuring data duplication to the next pipe element Vessel local Flexibility Calculations Multiple load case spring hanger design Algebraic load case combinations Nonlinear restraints with gaps, friction, 2-node, and skewed options Zero or finite length expansion joints with “Tension Only” tie-bars Built in database of pipe materials and properties B31 code compliance reports Static and dynamic capabilities, including animated mode shape plots Extensive input/output graphics Pressure effects on bends, including consideration of circular or slightly oval cross-sections

Chapter 10 Update History

CAESAR II Version 1.1S Features (2/86) Help Windows AutoCAD Interface HP Plotter Interface Batch Execution Opinion Accounting System File Handler Spooled Input Listings Uniform Load in G’s Liberal Code Stress Allowable Cursor Pad and Function Key Implementation in Input Spreadsheets Plot Menu Single Keystroke Access Stainless Steel Pipe Schedules Direct Input of Specific Gravity Bourdon Pressure Options Hanger Control Spreadsheet Updates

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CAESAR II Technical Reference Manual

CAESAR II Version 2.0A Features (10/86) AISC Structural Steel Database with over 800 different structural steel cross-sections. Keyword/Batch Structural Steel Preprocessor: Same quality CAESAR II graphics with structural steel volume plots, interactive error checking, extensive interactive help, and fully compatible with CAESAR II piping models. High Resolution Graphics: EGA support for monochrome and 640x350, 16 color more. Tecmar Graphics Master support for monochrome and 640x200, 16 color mode. Hercules support for monochrome 720x348 mode. Graphics: Addition of “PAN” and “RANGE” options, improved Zooming, stresses and displaced shapes in color, hidden lines removed from volume plots, and pipe and structure plotted together. 3D-Graph: Option to plot stresses for all nodes for all load cases on the same plot. Simultaneous Use Of Two Screens: One monochrome and the other graphics. WRC 107 Stress Calculations Units: English and SI standard options, or user may define his own set of unit constants and labels. Output may be generated in multiple unit sets, and input files may be converted from one unit set to another. Wind Load Calculations: According to ANSI A58.1-1982, or user may input his own velocity or pressure versus elevation tables. Pipe/structure “include” Option: Piping input from one file may be included in another with a given node and rotational offset. Quick Natural Frequency Range Calculations: Computes the number of natural frequencies in any user given range in the amount of time needed to do a single static solution. High Resolution Hardcopy Printer Plots SETUP FILE DIRECTIVES: Users may set the following CAESAR II execution parameters: - Graphics hardware configurations - Colors for over 27 different plotted items - B3.1 reduced intersection options - Plot/Geometry connection through CNODES options - Corroded cross section stress calculation options - Minimum and Maximum allowed bend angle options - Occasional load factors - Loop closure tolerance

Chapter 10 Update History

5

CAESAR II Version 2.1C Features (6/87) Uniform and Independent support shock spectrum capability. Force Spectrum Dynamic Analysis of Fluid Waterhammer. Force Spectrum Dynamic Analysis of Relief Loads. Force Spectrum Dynamic Analysis of Wind Gust Loads. Fluid Mechanics Analysis of Gas or Liquid open vent relief system. Includes vent stack sizing, thrust, and pressure rise computations. NRC Dynamics Benchmarks for: NUREG/CR-1677, BNL-NUREG-51267, Vol.I, 1980; and NUREG/CR-1677, BNL-NUREG-51267, Vol.ii, 1985. Dynamic “Friction” modelling based on static load case results. Eleven (11) pre-defined shock spectra including all Reg. Guide 1.60 spectra and the El Centro NorthSouth component spectra. Improved Harmonic Analysis including the effect of “phased” loading relationships. (Allows modeling of eccentrically loaded rotating equipment.) Improved dynamic output processor, includes user defined headings and user comments. Animated static and dynamic solutions with structural members and hidden line volume plots. Improved EIGENSOLVER many times faster than earlier algorithms, with automatic out-of-core solution mode. Updated Static Analysis Load Case Processor. New Friction Algorithm with interactive control during solution of nonlinear restraints. Improved Output file handling of various solution methods. Ability to abort any function at any time during a session using the <ESC> key. New keydisk, memory protection scheme. Hardware/Software QA capability for analysis verification.

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CAESAR II Technical Reference Manual

CAESAR II Version 2.2B Features (9/88) Large Rotation Supports—Allows large rotation supports to be handled properly, by computing the support forces in all three global directions. Rod and Chain hanger supports can be modeled now. Nonlinear Out-of-Core Solver—This new solver increases the range of problems CAESAR II can solve by allowing nonlinear solutions to be performed on the hard disk. This capability is necessary when a job is too large to be solved in memory. Friction Report—Friction is a non-conservative force, and CAESAR II treats it as such. The restraint reports will now show restraint loads due to friction for each load case. New External Interface Hooks—A new interface module will allow smooth interface to data conversion modules between CAESAR II and other programs, such as AutoCAD. A new AutoCAD DXF interface is provided, and two third part vendors have completed interfaces from their AutoCAD ISO packages to CAESAR II. ASCII Editor to an overwhelming need and subsequent lack of easy to use system editors, a stand alone ASCII editor is being provided. This editor will enable users to easily modify files such as AUTOEXE.BAT, CONFIG.SYS, and SETUP.CII. 2D XY Engineering Plotting Program—A stand alone plotting program is provided to allow users to plot engineering data, such as CAESAR II spectrum files. This program will plot any “real” data arranged in columns. Valve & Flange Database—The addition of a valve & flange database enables the user to define/select the specific rigid element to be inserted into the piping system. The database is constructed to allow user additions and/or modifications. Dynamic Restart—The most time consuming part of a dynamic analysis is the Eigensolution. This feature allows a job to be restarted and use a previous Eigensolution. WRC Updates latest edition (1979) of the WRC107 bulletin has been incorporated. Input Title Page—An optional title page has been added to the input module of the program. Users can now define a title page of up to 19 lines, which will be stored with the input. Expansion Joint Rating Program—This stand alone program allows the user to compute the compression of each expansion joint corrugation and the compression of the joint as a whole. These values can then be compared to manufacturer’s recommendations for joint acceptance.

Chapter 10 Update History

7

CAESAR II Version 3.0 Features (4/90) VGA Graphics support (on input) Interactive (immediate) rotation of the input graphics image Updated graphics user interface Optional WRC 329 implementation of new stress intensification factors for intersections Optional ASME Class 1 flexibility calculations for reduced intersections Optional WRC 329 fixed to B31.1 and B31.3 piping code equations Piping codes: B31.4, B31.8, ASME Sect III Class NC and ND, CAN Z184 and Z183, Swedish Power Methods 1 and 2, BS806. Updated SIF library to include welded joints and Bonney Forge fittings New scrolling help screens Editing list features, including rotate/duplicate of total or partial models Updated WRC 107 table limit check AISC member check Wind load calculations on structural members Additional stress equation control via the SETUP file Numerical sensitivity checks in both the in-core and out-of-core solvers Automatic expansion joint modeler using manufacturers database Additional restraint types including bottomed-out spring hangers and bi-linear soil springs.

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CAESAR II Technical Reference Manual

CAESAR II Version 3.1 Features (11/90) Graphics Updates Instantaneous center-of-rotation calculation Element Highlight Element Range

Rotating Equipment Report Updates API 610 7th Edition Addition SI/User Units HEI Additions

WRC 107 Updates Simplified input WRC 297 stress calculations

Miscellaneous Modifications Screen data presentation changes Direct control jumping between executables Increased number of allowed program designed hangers Additional spring hanger design options Database Updates include additional spring hanger tables Soil Modeler for Buried Pipe

Chapter 10 Update History

9

CAESAR II Version 3.15 Features (9/91) The installation program utilizes the file compression routines from PKWARE. This significantly reduces the number of diskettes distributed and the time needed to install the CAESAR II package.

Flange Leakage and Stress Calculations Elastic models of the annular plate, gasket and bolts predict the relative degrees of gasket deformation leading to a leaking joint. Stress calculations in accordance with ASME Sect. VIII Div. 1 are also provided for comparison.

WRC 297 Local Stress Calculations This bulletin supplements WRC 107, and in addition computes stresses in the nozzle as well as the vessel.

Stress Intensification Factor Scratchpad The new module shows the effects of the various code options available in CAESAR II, and illustrates the relationship between the various interpretations. WRC 329 SIF options are included. SIFs for stanchions on elbows are also computed.

Miscellaneous A pen plotting program (PENPLT) plots up to 2500 element models (LARGE Includes) on the screen or on an HPGL compatible hardware device. The static output processor has been updated to support VGA graphics and to provide screen dumps to HP Laser Jet Series II compatible printers. Updated SYSCHK program now checks that SHARE is loaded when necessary. Missing coprocessor is also immediately reported. Updated PLTS now allows users to save labels, scaling information, and file names during plotting sessions. Updated ROT (rotating equipment program) provides additional code interpretations for the HEI bulletin. The BIGPRT (large job printing program) has been expanded to handle even larger jobs and to provide a “local” element report. As of Version 3.15, CAESAR II will utilize ESL devices to authorize access to the program. The ESLs are more stable than the previously used keydisk and provide additional client information to the program. Additional information on the ESLs can be found in the update pages for the User Manual. Note: The first access of Version 3.15 will cause the ESL activation code to prompt for the keydisks (both unlimited and limited). Both keydisks must be available to properly activate the ESL. A printer setup program (PRSET) is provided to adjust the number of lines per logical page for dot matrix printers. Users with page lengths longer than 11 inches will find this program very useful.

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CAESAR II Technical Reference Manual

CAESAR II Version 3.16 Features (12/91) The internal file maintenance utility has been completely rewritten. The new file handler provides the same capabilities as the previous file handler but with faster response times. Additionally, the new file handler is compatible with disk partitions larger than 32 Mbytes, and manipulates the data files created by Versions 3.xx of CAESAR II. A configuration program has been added to CAESAR II to allow users to modify the SETUP.CII file from spreadsheets. The configuration program also includes the standard COADE help interface to facilitate setting the directives. The structural programs (C2S and AISC) have been revised to access either the 1977 AISC database or the 1989 AISC database. Additionally, the AISC program has been updated to perform the unity checks (code compliance) using the 1989 code, which includes the methodology for checking single angles. The equipment module (ROT) has been enhanced to handle vertical in-line pumps for API-610, 7th Edition. The Stoomwezen 1989 (Dutch) piping code has been added. Three additional spring hanger tables have been added (Basic Engineering, Capitol Pipe Supports, Piping Services Company). The editors found in the structural preprocessor, the ASCII file editor, and the piping preprocessor title page have been modified to allow the insertion and deletion of single characters. Appropriate screen instructions are provided where necessary. An “automatic loop closure” command has been added to the piping preprocessor. A “jacketed pipe” example has been included in the documentation. The input file for this example is included in the EXAMPLES set on the distribution diskettes. Updated moduli of elasticity for default CAESAR II materials based on 1990 code revisions.

Chapter 10 Update History

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CAESAR II Version 3.17 Features (3/92) Support of DOS environments now available in CAESAR II. This allows users to run the software from various subdirectories on the hard disk, other than the installation directory. Facilities have been provided to enable the user to modify the default colors used through out CAESAR II. Four predefined sets of text colors are provided as well as the ability to modify whichever set is currently selected. The Utilities menu has been expanded to include all of the secondary CAESAR II processors. Help has been added for the Input graphics, the Pen Plot graphics, and WRC 107. A new online error processor has been incorporated. This enables the software to provide the user with an explanation of the cause of many fatal error messages, as opposed to the display of only the error number. The file handler has been modified to allow the manual entry of a new job name. The input piping preprocessor now includes a material number (21) for User Defined Materials. The Static and Dynamic Output menus have been modified to allow the user to return directly to the input, or in the case of the dynamics output, to invoke the animation module directly. Graphics for flange selection and output have been added to the ASME Flange modules. Input and output file sequencing are checked to aid in Quality Assurance, insuring that the current input file produced the current output file. Input Echo reports are also possible from the static output processor.

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CAESAR II Version 3.18 Features (9/92) Codes and Databases The Canadian codes Z183 and Z184 have been revised according to the 1990/1992 publications. The Italian spring hanger manufacturer INOFLEX has been added. The Database option of the configuration program now allows the user to set the desired valve and flange database. Additionally a database excluding flanges (NOFLANGE) is included. The Material Database used for the Flange Stress/Leakage module has been updated. The new database includes all changes from the ASME Sect VIII, Division 1, A91 Addenda, the materials are listed in code order, and the number of materials has increased from 450 to 1100. The structural modules (C2S and AISC) have been updated to work with the German structural steel library, which is also included.

Interfaces Added A new neutral file interface is provided which allows a two way transfer of data between the CAESAR II input file and an ASCII text file. An interface is provided between Stoner’s LIQT program and the dynamic modules of CAESAR II. This interface enables dynamic pipe forces from a time domain analysis to be used in the generation of a force spectrum.

Miscellaneous Changes The static stress summary report has been modified so that the maximum code stress percent is reported, not the maximum code stress. A “miscellaneous” option has been added to the configuration program. This option allows various options, including the specification of either the ANSI, JIS, or DIN piping specifications. Other options available from the Miscellaneous menu are: Intro/Exit Screens (On/Off) - This option can be used to disable the display of the initial entry screen and the final exit screen. Yes/No Prompts (On/Off) - This option can be used to disable the yes/no/are_you_sure prompts. Output Reports by Load Case (Yes/No) - By default, CAESAR II produces static output reports by load case. This option can be used to generate the same reports by subject. Displacement Report Node Sort (Yes/No) - This option can be used to disable the nodal sorting of the static displacement report. The file handler has been modified to enable directory and disk drive selection and logging. The initial display of the file names can also be controlled by the user. This allows the user to set the sort order as well as the single/multi-column display presentation. A file verification routine has been added to check the installation of CAESAR II. This will aid in detecting program corruption due to hard disk defects and viruses. A new report has been added to the static output menu. This will enable users to obtain a “local force/moment” report for the elements in the system. A 32 bit version of the dynamic summation module is provided for large dynamic analysis. Note, this module requires at least a 386 processor. The animation module has been modified to provide hard copy output of the mode shapes.

Chapter 10 Update History

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CAESAR II Technical Reference Manual

CAESAR II Version 3.19 Features (3/93) Batch Stream Processor—A new processor has been included which will allow multiple jobs (up to 12) to be run in series, without user intervention. The jobs can be static analysis, dynamic analysis, or both. Expansion Joint Database—The Pathway Bellows expansion joint database has been updated. The new database includes two additional pressure classes and diameters out to 144 inches. A new expansion joint database from RM Engineered Products has been added for this release. Input Echo—The input echo processor has been modified so that the input echo precedes the output data. Additionally, the intermediate data generated by the error checker now appears in this listing. B31G—The B31G criteria for the remaining strength of corroded pipelines has been incorporated. This module includes the original B31G criteria as well as several of the modified methods discussed in the Battelle project. Output Processor—A new report has been added to the output processor which generates a Restraint Summary report. This summary details all the loads for all selected load cases for each restraint in the model. Thermal Bowing—The effects of thermal bowing on horizontal pipes can be analyzed. By specifying the thermal gradient between the bottom and the top of the pipe, CAESAR II will compute the loads induced and include them with the thermal loads. 32 Bit Modules—All of the dynamic modules have been moved from the 16 bit mode to the 32 bit mode. Additionally, the animation program now supports EGA and VGA display modes. Title Page Template—A user-configurable ASCII text file can now be used as a title page template. Interface Updates—The CAESAR II data matrix interface and the Autoplant interface have both been updated to utilize the currently active units file. The ComputerVision interface has been updated to handle “tube” type piping. Expansion Joint Rating—The expansion joint rating module, ERATE, has been moved into the “Miscellaneous Module”, facilitating input via the standard spreadsheets. Refractory Lining—The computation modules of CAESAR II have been modified to accept a negative value of insulation thickness. If a negative thickness is encountered, the program will assume the insulation is refractory lining (inside the pipe). Minimum Required Thickness—The piping error checker now makes the “minimum required thickness” computation according to B31.1, 104.1. This information is reported for each pipe in the listing of intermediate data (See item 3 above). Spring Hanger Tables—The E. Myatt & Co. spring hanger table has been added. ESL Updates—All of the code used to access the ESLs has been updated to allow access to the 50 and 66 Mhz CPUs. Missing Mass—The dynamics modules can consider missing mass effects in the spectrum solutions. SEISMIC ANCHOR MOVEMENTS—The dynamics modules will allow the specification of seismic anchor movements for independent support motion analysis. RCC-M—The French piping code RCC-M, Section C has been incorporated. Languages—The input and dynamic output supports English, French, and Spanish language headings. Language dependent files can be activated with the appropriate command line switch on the INSTALL directive. For example, INSTALL /S will install any Spanish specific files. PCX Files—All of the graphics modules have been modified to allow the images to be saved to disk files in PCX format. This will enable these images to be brought into word processing and desktop publishing systems.

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CAESAR II Version 3.20 Features (10/93) A completely new set of documentation accompanies this release. This documentation consists of: a User Guide, an Applications Guide, and a Technical Reference Guide. The static in-core and out-of-core solvers have been converted to run in 32 bit protect mode utilizing extended memory. Solution times for large jobs have been cut by an order of magnitude. The Static Output processor has been converted to run in 32 bit protect mode utilizing extended memory. Both the Static and Dynamic Output processors now have the capability to generate ASCII disk files on any drive or directory (using the COADE file manager) on the computer. Additionally, a table of contents summarizing the output is generated for printer and disk devices. The Dynamic Output processor now includes titles and page numbers (similar to statics), and provides input echo (both system and dynamic) abilities. Modal time history analysis has been added. This includes output report review and animated response review. Standard spectrum analysis now include modal components for displacements. Additionally displacement information is now available for static-dynamic combinations. The Included Mass Report has been clarified and modified to include the active mass in each of the global directions. The percent of the force included/added is now based on a vector sum rather than an absolute sum. The ZPA used in the missing force correction can now be controlled via the configuration file. The user can specify that the ZPA be based on the last extracted mode or the last spectrum value. The static load case array space has been increased by a factor of 5, allowing more flexibility in static load case setup. API 650 nozzle flexibilities, according to the ninth edition, July 1993. Checks for allowable loads on Fired Heater Tubes according to API-560 have been added. As an option, users can consider the effects of pressure stiffening on straight pipes. Three additional spring hanger tables: Sinopec (China), BHEL (India), and Flexider (Italy). The Australian structural steel shape database has been added. The ASME material database has been updated to reflect the 1992 Code addendum. The printer testing routines have been completely rewritten. Additionally, output can be directed to any LPT port. The ability to configure the printer, either dot matrix or laser jet. This is implemented via a text file containing the printer formatting codes, which the user is free to modify. Password protection for input data files, to prevent modification of completed projects. All of the screens in the piping preprocessor (except for the main spreadsheet) are now supported in Spanish and French. Input/Output file time/date sequencing checks have been added to the dynamics modules. The “break” command in the piping input processor has been modified to accept input in feet-inch units instead of only feet. This should allow compound entries in any units system.

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CAESAR II Technical Reference Manual

CAESAR II Version 3.21 Changes and Enhancements (7/94) Most of the CAESAR II executable modules have been converted from Microsoft 16 bit FORTRAN to WATCOM 32 bit FORTRAN. This has reduced the low DOS RAM requirements of the program from 577k to 475k. The modules converted to 32 bit operation for Version 3.21 are summarized below: Static Stress Computation Module (1) Piping, Buried & Structural Steel Input Modules (3) Piping Error Checker (1) Load Case & Dynamic Input Module (1) All CAD interfaces (8) Neutral File interfaces (2) The software now supports an ESL from a new vendor. This provides CAESAR II with full networking abilities. The program first checks for a local ESL (from either vendor), then for a network ESL. Toward the support for network operations, the data files which are not job specific are now assumed to be located in a SYSTEM subdirectory underneath the CAESAR II installation directory. These data files include: the input listing formatting files (*.INP), the accounting data files, the printer formatting file, the file handler template file, and the various header files. The common factor among all of these files is that they are specific to a company installation, not a particular data directory. Up until Version 3.21, these data files were manipulated by the program (or sometimes directly by the user) in the installation directory. However, many network installations “write protect” their installation directories, making modifications to these files impossible. We have therefore placed these files in a SYSTEM subdirectory to which users should be given complete access. Note: CAESAR II Version 3.21 will be capable of running on a local machine (with either vendor’s local ESL) or on a network (with the network ESL). The changes made to the software enable the same version to be run under these various configurations. Added additional spring hanger manufacturer has been added, Carpenter & Paterson, UK. The UBC (Uniform Building Code) earthquake spectra have been added. The B31.5 piping code has been added. The piping code addenda have been reviewed and any necessary changes made to the software. The addenda include revisions for: ASCE #7, B31.1, B31.8, ASME NC, and ASME ND. The SIF scratch-pad from the Miscellaneous processor (Option C of the Main Menu) has been incorporated into the piping preprocessor. This processor includes all of the supported piping codes (not just B31.1 and B31.3 as before) and all of the fittings. Additionally, any changes made to the scratch-pad data can optionally be transferred directly to the main CAESAR II data spreadsheets. Additional changes to the input piping preprocessor include the following: 1problem size is now dependent on the amount of free extended memory - the old limit of 400 elements is now upwards of 8,000 elements 1graphics menus automatically turned off for hard copies

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1optional node number display for supports, anchors, hangers, and nozzles 1unction key map shown on main spreadsheet 1auxiliary input spreadsheets support help The accounting system has been completely rewritten. This provides a more streamlined interface. Additionally, accounting statistics are now recorded from the stress computation modules (previous versions only recorded the actual matrix decomposition times). The API-617 and NEMA-SM23 reports have been overhauled so that the code compliance when using non-English units systems is consistent. The new Flange Rigidity factor from ASME Section VIII has been added. A new loader (C2.EXE) has replaced the original one (C2.COM). This new loader performs initial startup checks, with diagnostic reporting if necessary, and enables error processing from the Main Menu. The configuration program has been modified to track changes. Users attempting to [Esc] out after making changes are warned that the changes will not be saved. A graphics viewer has been added to the file manager. This enables rapid model plotting directly from the file manager of the Main Menu. Additional directives are available to disable the generation of the Table of Contents page, and disable the display of the spreadsheet function key mapping.

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CAESAR II Version 3.22 Changes & Enhancements (4/95) The following enhancements and additions have been added to CAESAR II for the Version 3.22 release. Any “Technical Changes” made, which could affect the computed results, are listed on the following page. The Harmonic solver has been updated to provide “damping”. Harmonic analysis can now include or exclude damping as the user deems necessary. The following codes have been reviewed (and any necessary changes made) for compliance to the latest editions: B31.1, B31.3, B31.4, B31.5, B31.8, NC, ND, and BS-806. The following additional piping codes have been added: RCCM-D, CODETI, TBK 5-6. Center of Gravity calculations have been added, with results displayed in the error checker. A Bill of Materials report has been added. Yield criterion stresses can be computed as either Von Mises or as 3D Maximum Shear Stress intensity. Hoop Stress can be computed based on Outer Diameter, Inner Diameter, Mean Diameter, or Lame’s equation. The spring hanger design spreadsheet has been modified to default to a 25% load variation. In addition, the actual hanger load variation now appears in the hanger output reports. A new command (WIND) has been added to the structural steel preprocessor. This allows selective wind loading on an element by element basis. A new key-combination Alt-D is available in the input processor to compute the distance between two nodes. User specified coordinates for up to 30 nodes are saved in the input file. The input title page has been expanded from 19 to 60 lines. Automatic node numbering abilities have been added to the spreadsheets of the main piping input module Expansion Joint databases from IWK (Germany) are provided. Expansion Joint database from Senior Flexonics is provided. MISC converted to 32 bit operations. This module provides the SIF, Flange, WRC297, B31G, and expansion joint rating computations. ROT converted to 32 bit operations. This module provides the equipment calculations for NEMA, API, and HEI. General revisions made for more consistent input screens and help messages. A new report option (in static output) is available to review the “miscellaneous” computations made by the error checker. This report includes: SIFs and flexibility factors, pipe properties, nozzle flexibility data, wind data, CG data, and the bill of materials report. The Intergraph Interface has been improved. The interface now transfers the temperature/pressure pairs. Additionally, if a material mapping file is present, material data can be set correctly by CAESAR II. The CADPIPE Interface has been updated in accordance with CADPIPE Version 4.0. The Restraint Summary in the static output processor has been modified to include the translational displacements of the restrained nodes. The output processors (static and dynamic) have been modified to allow users to change the name of the disk output file if desired. Additionally, modifications have been made so that only a single output device can be enabled.

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All “language” files have been translated into German. Use “INSTALL /G” to acquire the German files. A new control F8 at the output menu level allows switching jobs without returning to the Main Menu.

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CAESAR II Technical Reference Manual

CAESAR II Version 3.23 Changes (3/96) The following items have been completed for the 3.23 release: Mouse support has been added to most modules. The German piping code, FBDR, has been added. Major improvements to FRP (fiber reinforced plastic) stress calculations. This includes the BS 7159 code and guidelines set forth by FRP manufacturers. A bi-directional link to CADWorx/PIPE (COADE’s Piping CAD system) has been added. The WRC107 module has been redesigned to incorporate multiple load cases and perform the ASME Division 2 Stress Intensity Summation, all in one step. An interface to Sunrise System’s PIPENET program has been developed. The South African structural steel tables are being added. Two new spring hanger manufacturer’s tables have been added; Comet (UK), and Hydra (Germany). Two new commands have been added to the structural preprocessor: UNIT, and GLOAD. The CADPIPE interface has been updated to comply with the new release (Version 4.1) of CADPIPE. Additional modifications have been made to the Intergraph interface. The low DOS RAM requirement has been reduced to 420 Kbytes. The equipment module has been updated to reflect the 1995 edition of API-617. The following U.S. piping codes have been updated according to recent editions: B31.3 (1995)

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CAESAR II Version 3.24 Changes & Enhancements (3/97) The following items have been added or modified for the 3.24 release: Multiple (3) displacement/force/uniform load vectors have been added. Note that these load cases, called D1/D2/D3 and F1/F2/F3, may be toggled on the input plot by continuing to press F3 and F5 (displacements cycle through D1, D2, D3, and then off). The naming of these load cases has also required the renaming of the CAESAR II load combination terms – D1, F1, S1, etc. must now be called DS1, FR1, and ST1. Note that all hanger loads and cold spring forces (from materials 18 and 19) are still lumped into load case F1, for consistency with previous versions of CAESAR II. A material database for piping properties and allowable stresses for many of the piping codes supported by CAESAR II has been implemented. This is invoked by pressing [ALT-M] on the main CAESAR II input spreadsheet (also at the list option and on the WRC 297 nozzle flexibility spreadsheet). After bringing up the list of materials, a material name can be typed in; matching records are then displayed for selection. Allowable stresses are updated automatically whenever temperatures, materials, and/or piping codes change. Database management is provided from the Utilities option of the main menu. Users may edit COADE provided materials or add their own. Material parameters may be provided for code 0 (represents generic values for any non-specified code) or for specific codes. It is recommended (due to future implementation plans) that metals be assigned identification numbers between 100 and 699, while FRP materials receive numbers between 700 and 999. Note that selection of FRP materials from the material database will not currently activate the orthotropic material model in CAESAR II. This must still be done through the use of material 20 (see item 6 concerning this below). Eight-character job names are now supported (input files are identified by extension ._A, output files by extension ._P, ._S, etc.). Existing files are automatically recognized and converted to their new format. (See related item 16 below.) Modifications have been made to allow multiple users working from the same network data directory via the environment variable COADE_USER. This environment variable should be set to a unique 3 character combination (i.e., the user’s initials) for each user working in the common directory. Implementation can be done by adding to the user’s AUTOEXEC.BAT file a line such as: SET COADE_USER=TVL CAESAR II’s Valve and Flange database now incorporates data files from CADWorx/Pipe. This change provides four advantages: Component weights and lengths are more accurate, as well as traceable to specific catalogs, standards, etc. Weights and lengths are provided for more components than were previously available in the CRANE or GENERIC databases. Since CADWorx/Pipe data files are text files, users may easily edit or add components. If the user also has CADWorx/Pipe on their machine, the two programs will share the same data files and project specs, enhancing the performance of the bi-directional interface. Gaskets are included for flanged items, so a better fit is provided between the CADWorx/Pipe and CAESAR II models.

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The user may now set default values for FRP (material 20) parameters via the configuration/setup. These default parameters may be read automatically from manufacturers data files by toggling through the list of available files, and then pressing [ALT-U] (for Update) on the selected vendor file. Vendor files are recognized by their .FRP extensions; since these are text files, users may create them easily themselves, or vendors may distribute them to their customers. The UKOOA (United Kingdom Offshore Operators Association) piping code for FRP piping has been added. The Z183 and Z184 piping codes have been replaced with the Z662 code, which has been expanded to consider calculation of stresses in “restrained” piping. The ASCE #7 wind code has been updated to the 1995 edition. The API-610 code in the equipment module has been updated to the 8th edition. ASME Section VIII Division 2 stress indices and WRC-107 SIF (kn, kb) values have been incorporated into the WRC-107 module. The “Relief Load Synthesis” dynamics module now supports metric (or custom) units. A number of configuration file default values have been revised in order to improve calculational results or program performance: Changed

From

To

BEND_LENGTH_ATTACHMENT=

5.0

1.0

BEND_AXIAL_SHAPE =

NO

YES

FRICT_STIFF =

50000

1.0E6

FRICT_NORM_FORCE_VAR =

25

15

FRICT_ANGLE_VAR =

30

15

VALVE_&_FLANGE =

GENERIC

CADWORX

Four new directives added to the configuration file. SYSTEM_DIRECTORY_NAME—User defined, defaults to SYSTEM (note user may now maintain multiple system directories for different projects) UNITS_FILE_NAME—User selected from list (note current units are now set through the configuration/setup, not through the units option of the main menu) BS_7159_PRESSURE_STIFFENING—Design strain or Actual Pressure FRP_PROPERTY_DATA_FILE—User selected from list The configuration file can also be password protected in the Installation Directory. This prevents modification of all Computation and Stress Control directives. Subsequent use of the configuration module prevents modification of these directives, unless the password is known. Colors, printer settings, etc. may still be changed by users without the password.

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CAESAR II has been modified to accept an optional job name (including full drive and path data) as an argument; the program switches to the appropriate drive and directory, opens the specified job, and goes into input (bypassing the Main Menu). This allows the definition of ._A files as CAESAR II input files (under Windows 95) and subsequent double clicking on the file name in a Windows/95 explorer window to start the input processor on the picked job file. This also allows CAESAR II to be spawned from other programs, right into a job. Modifications to CAD interfaces: Intergraph and CADPIPE. All necessary routines have been checked (and modified where appropriate) to address the “Year 2000” issue. A Korean structural steel shape library has been added. A new spring hanger table has been added (SARAFTHI). PD-5500 nozzle flexibilities have been incorporated to complement the WRC-297 and API 650 nozzle connections.

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CAESAR II Version 4.00 Changes and Enhancements (1/98) The CAESAR II Version 4.00 release is a major program rewrite making it compatible with Windows 95/NT (version 4.0) operating systems. Minimal functionality enhancements were included in order to make CAESAR II input files interchangeable between Version 4.00 and CAESAR II Version 3.24, the last DOS-based version. Specific new features include: Simultaneous review of graphics and spreadsheet. Addition of rendering and wireframe graphics in plot mode. The ability to turn off subsequent occurrences of an error type in the piping error checker. The ability to extract loads directly from a piping output file for inclusion in the WRC 107 and rotating equipment modules. Addition of bend mid-point modes (indicated by angle “M”) which allow the user to designate the mid-point of the bend without knowing the included angle. Ability to review 132-column reports on screen.

Chapter 10 Update History

CAESAR II Version 4.10 Changes and Enhancements (1/99) CAESAR II version 4.10 changes and enhancements (1/99) include 9 temperatures, 9 pressures, 9 displacement sets, and 9 force/moment sets Finalization of TD/12 piping code Fatigue capabilities including cumulative damage Increase in number of load cases to 99 Reactivation of the input LIST facilities Printing capabilities for graphical renderings Saving graphics images to BMP files Online user’s guide and quick reference guide in PDF format Update of piping codes (CODETI, NC, ND, B31.1, B31.3) Addition of results filters to output reports Update of technical reference manual to reflect Windows version of CAESAR II Variability of mill tolerance on an element-by-element basis

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CAESAR II Version 4.20 Changes and Enhancements (2/00) CAESAR II version 4.20 changes and enhancements (2/00) include New Input Graphics - utilizes a true 3D library, enabling graphic element selection New "local coordinate" element input/specification Completely revised material data base, including Code updates. Optional static output in ODBC compliant data base format. Hydrodynamic loading for offshore applications. This includes the Airy, Stokes 5th, and Stream Function wave theories, as well as Linear and Power Law current profiles. Wind analysis expanded to handle up to 4 wind load cases New piping codes: B31.4 Chapter IX, B31.8 Chapter VIII, and DNV (ASD) A wave scratchpad - see the recommended theory graphically, or plot the particle data for the specified wave. Updated piping codes: B31.1, B31.3, B31.4, ASME NC, and ASME ND Automatic Dynamic DLF Plotting Hydra expansion joint data bases As a result of the merger between Senior Flexonics and Pathway Bellows, a new expansion joint data base replaces the two previous individual data bases. A new spring hanger vendor (Myricks) is provided. PCF Interface

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CAESAR II Version 4.30 Changes and Enhancements (3/01) New Static Load Case Builder / Editor. Allows multiplication factors on load components plus additional combination methods (SRSS, Algebraic, ABS, Min, Max, Signed Min, Signed Max, and Scalar). Z-Up: Build or review models with "Z" as the vertical axis instead of "Y". Switch between "Y" and "Z" up on the fly. New "undo/redo" ability in the piping input module. Piping input can be sent to ODBC database. A new "data export" wizard is provided to selectively target input or output data for ODBC export. All modules support optional output directly to MS-Word. Updated piping codes: B31.1, B31.3, B31.4, ASME NC, and ASME ND. User Control over the "auto-save" feature implemented. Improvements to the 3D graphics (job specific configuration, additional data display). Added graphics to the WRC 107 Module to show loads and orientation. Added a new "Code Compliance" report to the static output processor. Spring hanger design expanded from 3 to 9 operating cases.

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CAESAR II Version 4.40 Features Revised piping codes: B31.3, B31.4, B31.5, B31.8, ASME NC, ASME ND Added the B31.11 piping code. Added an alpha-numeric node label option to the piping input module Expanded Static Load case options: (1) added load components H, CS, HP, and WW (hanger loads, cold spring, hydro pressure, and weight filled with water, respectively), (2) added HYDRO stress type, (3) added option to set snubber and hanger status on a load case basis, (4) provided ability to scale friction factor on a load case basis. Added automatic generation of a hydrotest load case (WW+HP, HYD stress type, and spring hangers locked), triggered by the presence of a non-zero HP. Updated the 3D input graphics, as well as partial implementation in the static output processor (including the "Element Viewer"). Updated the spring hanger design algorithm to provide the option to iterate the "Operating for Hanger Travel" load case to include the stiffness of the selected hanger. Added new configuration options for ambient temperature, default friction coefficient (if nonzero, automatically gets applied to new translational restraints), liberal stress allowable, stress stiffening, and Bourdon settings, as well as how to handle B16.9 welding tee and sweepolet SIFs in B31.3. Added two new spring manufacturers tables Pipe Supports USA and Quality Pipe Supports. Added the ability to define the flexibility factor on bends. Included piping and structural files now support long file names, may be located in any directory path, and the number of included structural files has been expanded from 10 to 20. Results of the Hanger Design Cases are now optionally viewable in the Static Output Processor (set status to "KEEP" in the Load Case Options). Added the ability to filter static Restraint reports by CNODE status. Added a new "warning report" to the static output. Added a "dirty flag" to the piping input preprocessor and the configuration modules. Attempting to exit these processors without saving changes produces a warning message. Added the ability to detect the differences between material data in the input file and that in the material database (including missing "user materials"). This feature offers the user the opportunity to use the original data. Reviewed/updated the "minimum wall" computation for all piping codes for straight pipe. Added a field for specifying Marine Growth Density to the Wind/Wave dialog. Updated API-661 to 4th Edition. Added the ability to save static load case data without running the job.

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CAESAR II Version 4.40 Technical Changes and Enhancements ( 5/02) The following list details changes to CAESAR II for Version 4.40, which may affect the numeric results. In the "flange module", a change has been made in where Peq is applied. Previously, Peq was used everywhere the pressure term was included in an equation. As of Version 4.40, Peq is only applied to the computation of "H". The design pressure is applied to the computation of "HT" and "HD". The A01 (2001) addendum to B31.3 exchanged the equations (between the figure and the notes) used to compute the "flexibility characteristic" for welding tees and welded-in contour inserts (sweepolets). This change will cause the SIFs for these fittings to change accordingly. CAESAR II defaults to the updated equation in the figure, which is more conservative. Users can control this choice with a new configuration option. In the ambient field of the Special Execution Options tab, a temperature value entered as zero is now assumed to be zero, instead of ambient. The "Bergen" and "Fronek" spring hanger data files have been updated to comply with new hardware supplied by these vendors. Existing jobs using these hanger databases may yield slightly different results Cold Spring and Spring Hanger loads are no longer components of "concentrated force vector #1 (F1), as they were in previous versions. These loads are now represented by "CS" and "H" in the load case definitions. The static load case editor no longer recommends load cases with "F1". This is because spring hanger preloads and cold spring have now been separated from this basic load component. It is up to the user to include F1, if present, in the appropriate load cases. For B31.3 and NAVY505 piping codes, the software has been changed so that allowable stresses are no longer divided by the joint efficiency. (This should not present many problems, since division by the joint efficiency has not been required for the B31.3 code since 1980.) This change was necessary in order to properly perform the minimum wall thickness calculation. The minimum wall thickness computation has been reviewed for each piping code supported by CAESAR II. Adjustments have been made where appropriate (B31.3, B31.4, B31.8, BS806, CODETI). Mill tolerance is now considered in Stoomwezen jobs and B31.8 Ch VIII jobs. (In the case of B31.8 Ch VIII, mill tolerance only affects the combined stress calculation.) Allowable stresses are now given for BS-7159 and UKOOA for the Sustained and Occasional load cases. These are identical to the Operating allowables. Spring Hanger Algorithm Update: The spring hanger design algorithm has been improved to repeat (iterate) the "free thermal" design load case in the event poor hanger locations result in "zero load hangers". The improved algorithm also accounts for frictional effects in the iteration scheme. For analyses using the B31.8 piping code, an additional (OPE) load case is recommended as the absolute sum of the Expansion and Sustained load cases. This additional load case better reflects the intent of section 833.4 of the code. A change was made as to how local forces are computed in combination cases. Prior to 4.40, global forces were rotated to obtain local forces. Now, in combination cases, local forces in combination cases are combined directly. This change may affect combination methods of Scalar, SRSS, and ABS.

1

Index + +Mill Tol % • 8

< • 32

3 3D Graphics • 134 3-D space • 5

A Absolute Expansion load • 4 Method • 75 Method Absolute Method • 77

Absolute Method • 77 Acceleration Factor • 71 Vector • 49, 59 Access • 103 Access Protected Data • 33 Access-protected dataAccess-protected data • 33 Account number • 1 Accounting • 1, 2 Menu • 1 Summary reports • 1 System • 1 Accounting file • 8 Accounting file structure • 8 Accounting File Structure • 8 Acoustic Flow problems • 49 Resonances • 86 Shock • 89 Vibration • 3 Activate • 114 Accounting tab • 1 Activate Bourdon Effects • 114 Actual pressure • 25 Add • 13 Add f/a in stresses • 14 Add F/A in Stresses • 14 Add torsion in sl stress • 15 Add Torsion in SL Stress • 15 Added mass coefficient • 35 Added Mass Coefficient, Ca • 62

Advanced Parameters • 82 Advanced parametersAdvanced parameters • 82 Airy wave theory • 30 Airy wave theory implementation • 33 AIRY Wave Theory Implementation • 33 AISC 1977 database • 55 AISC 1977 Database • 55 AISC 1989 database • 60 AISC 1989 Database • 60 All Cases Corroded • 13 Allow short range springs • 44 Allow Short Range Springs • 44, 108 Allow User's SIF at Bend • 13 Allowable Load variation • 42 Stress • 63, 44 Allowable load variation (%) • 42 Allowable Load Variation (%) • 42, 108 Allowable stress • 63 Allowable Stress • 41 Allowable stressAllowable Stress • 41 Allowable Stresses • 63 Allowed Intersection / Joint Types • 87 Alpha • 22, 18 ALPHA • 18 Alpha tolerance • 8 Alpha Tolerance • 4 Alpha toleranceAlpha tolerance • 4 Alternating pressure • 86 Ambient temperature • 75, 117 Ambient Temperature • 4, 117 Analysis Type (Harmonic/Spectrum/Modes/Time-History) • 49 Analysis type (harmonic/spectrum/modes/timehistory)Analysis Type • 49 Anchor • 33 Anchor Movement (Earthquake Only) • 25 Anchors • 33, 133 Angle • 15, 34 ANGLE • 2, 34, 36 AngleAngle • 36 Angular Forcing frequency • 49 Frequency • 54, 59 Stiffness • 101 ANSI

2

Update History

A58.1 • 24, 27 B36.10 • 7 B36.10 Steel Pipe Numbers • 7 B36.19 • 7 Nominal Pipe OD • 6 API 650 Delta T • 55 API 650 Fluid Height • 55 API 650 Nozzle Height • 54 API 650 NOZZLES • 53 API 650 Reinforcing 1 or 2 • 54 API 650 Specific Gravity • 55 API-650 Delta t • 55 Fluid height • 55 Nozzle height • 54 Nozzles • 53 Reinforcing 1 or 2 • 54 Specific gravity • 55 Tank coefficient of thermal expansion • 55 Tank diameter • 54 Tank modulus of elasticity • 55 Tank wall thickness • 54 API-650 Tank Coefficient of Thermal Expansion • 55 API-650 Tank Diameter • 54 API-650 Tank Modulus of Elasticity • 55 API-650 Tank Wall Thickness • 54 Append Reruns to Existing Data • 29 Applicable Piping Code • 39 Applicable Wave Theory Determination • 32 Applications - Utilizing Global and Local Coordinates • 142 Apply B31.8 Note 2 • 17 Archiving • 14 Area • 19 ASME Sect. VIII Division 2 • 44 Section VIII division 2 - elastic analysis of nozzle • 44 ASME III Subsections NC and ND • 108 ASME Section VIII Division 2 - Elastic Analysis of Nozzle • 44 Assume Standard Schedule • 73 Australian 1990 database • 69 Australian 1990 Database • 69 Auto Node Number Increment • 18 Auto node number incrementAuto node number increment • 18 Autosave Time Interval • 32 Auxiliary

Data • 125 Element data • 78 Processors • 1 Auxiliary Element Data • 78 Auxiliary fields Boundary conditions • 32 Component information • 14 Imposed loads • 59 Piping code data • 63 Auxiliary Fields - Boundary Conditions • 32 Auxiliary Fields - Component Information • 14 Auxiliary Fields - Imposed Loads • 59 Auxiliary Fields - Piping Code Data • 63 Available commands • 80 Available Commands • 80 Available Expansion Joint End-Types • 103 Available space • 41, 103 Available Space • 103 Axes • 22 Axial Elastic modulus • 26 Modulus • 11 Restraint • 75 Shape function • 3 Stiffness • 7 Axial strain Hoop StressAxial Strain

Hoop stress • 26 Axial Strain Hoop Stress (Ea/Eh*Vh/a) • 26 Axis Orientation Vertical • 2, 15

B B31.1 • 99 B31.1 (1967) • 118 B31.1 reduced z fix • 17 B31.1 Reduced Z Fix • 17 B31.11 • 106 B31.3 • 100 B31.3 sustained case SIF factor • 12 B31.3 Sustained Case SIF Factor • 12 B31.3 Welding and Contour Insert Tees Meet B16.9 • 13 B31.4 • 101 B31.4 Chapter IX • 103 B31.5 • 103 B31.8 • 104 B31.8 Chapter VIII • 105 Background • 22

Update History

Bandwidth optimizer • 122 Bandwidth Optimizer Options • 122 Base hoop stress Base hoop stress • 14 Base Hoop Stress On ( ID/OD/Mean/Lamés ) • 14 Base pattern • 29 Base Stress/Flexibility on (IGE/TD/12 code only) • 116 Basic element data • 76 Basic Element Data • 76 Basic loading case • 4 Basic material yield strength • 74 Batch mode • 9 Batch stream processing • 9 Batch Stream Processing • 9 Beams • 40 Fix • 40 Free • 40 BEAMS • 2, 40 Bellows • 105, 7 Allowed torsion • 102 Application notes • 102 Bellows Application Notes • 102 Bellows Stiffness Properties • 20 Bend Axial Shape • 3 bend flexibilty factor • 18 Bend Length Attachment Percent • 19 Bend Radius • 92 Bend SIF Scratchpad • 92 Bend Type/Laminate Type • 92 Bending stiffness • 7 Bends • 14 Axial shapeBends Axial shape • 3

Curvature • 19 Length attachment percentBends Length attachment percent • 19

Miter • 16 Node • 28 Radius • 16 Bends, tees • 133 Bends, Tees • 133 Bi-directional data transfer link • 4 Block operations • 125, 127 Block Operations • 127 Bonney forge sweepolets • 23 Bourdon pressure • 114 Bourdon Pressure • 7 Boxh • 20

3

BOXH • 20 Boxw • 20 BOXW • 20 Braces • 42 Fix • 42 Free • 42 BRACES • 2, 42 Branch Connections • 23 Flexibilities • 14 Pipe spreadsheet • 28 Stress intensification • 28 Branch error • 115 Branch Error and Coordinate Prompts • 115 Branch Pipe Outside Diameter • 92 Branch Pipe Wall Thickness • 92 Break • 80 Break command • 80 Break Command • 80 Browse • 27, 72 BS 7159 • 11, 23, 123 BS 7159 pressure stiffening • 25 BS 7159 Pressure Stiffening • 25 BS806 • 114 Building elements Elem, efill, egen, edimBuilding elements • 26 Building Elements - ELEM, EFILL, EGEN, EDIM • 26 Building Spectrum / Time History Load Cases • 23 Building spectrum load cases • 23 Buoyancy force • 32 Butt weld • 23, 79 Butt-welded tees • 23 BY • 24

C CAD Interfaces • 4 Cadcentre • 74 Cadpipe example transfer • 9 CADPIPE Example Transfer • 9 CADPIPE Interface • 5 Cadpipe log • 23 CADPIPE LOG File Discussion • 17 Cadpipe/CAESAR II data transfer • 23 CADWorx/PIPE • 82 CADWorx/PIPE database • 27, 82 CADWorx/PIPE directory • 82 CADWorx/PIPE link • 4 CADWorx/PIPE Link • 4

4

Update History

CAESAR II Fatal error processing • 11 File guide • 2 Initial capabilities (12/84) • 2 Log file • 26 Neutral file interface • 74 Operational (job) data files • 14 Version 1.1s features (2/86) • 3 Version 2.0a features (10/86) • 4 Version 2.1c features (6/87) • 5 Version 2.2b features (9/88) • 6 Version 3.0 features (4/90) • 7 Version 3.1 features (11/90) • 8 Version 3.15 features (9/91) • 9 Version 3.16 features (12/91) • 10 Version 3.18 features (9/92) • 12 Version 3.19 features (3/93) • 14 Version 3.20 features (10/93) • 15 Version 3.21 changes & enhancements (7/94) • 16 Version 3.22 changes & enhancements (4/95) • 18 Version 3.23 changes (3/96) • 20 Version 3.24 changes & enhancements (3/97) • 21 Version 4.00 changes and enhancements (1/98) • 24 Version 4.10 changes and enhancements (1/99) • 25 CAESAR II Fatal Error Processing • 11 CAESAR II File Guide • 2 CAESAR II Initial Capabilities (12/84) • 2 CAESAR II interfaces • 2 CAESAR II Local Coordinate Definitions • 137 CAESAR II Log File • 26 CAESAR II Neutral File Interface • 74 CAESAR II Operational (Job) Data Files • 14 CAESAR II Version 1.1S Features (2/86) • 3 CAESAR II Version 2.0A Features (10/86) • 4 CAESAR II Version 2.1C Features (6/87) • 5 CAESAR II Version 2.2B Features (9/88) • 6 CAESAR II Version 3.0 Features (4/90) • 7 CAESAR II Version 3.1 Features (11/90) • 8 CAESAR II Version 3.15 Features (9/91) • 9 CAESAR II Version 3.16 Features (12/91) • 10 CAESAR II Version 3.17 Features (3/92) • 11 CAESAR II Version 3.18 Features (9/92) • 12 CAESAR II Version 3.19 Features (3/93) • 14 CAESAR II Version 3.20 Features (10/93) • 15

CAESAR II Version 3.21 Changes and Enhancements (7/94) • 16 CAESAR II Version 3.22 Changes & Enhancements (4/95) • 18 CAESAR II Version 3.23 Changes (3/96) • 20 CAESAR II Version 3.24 Changes & Enhancements (3/97) • 21 CAESAR II Version 4.00 Changes and Enhancements (1/98) • 24 CAESAR II Version 4.10 Changes and Enhancements (1/99) • 25 CAESAR II Version 4.20 Changes and Enhancements (2/00) • 26 CAESAR II Version 4.30 Changes and Enhancements (3/01) • 27 CAESAR II Version 4.30 Changes and Enhancements (4/02) • 27 CAESAR II Version 4.40 Features • 28 CAESAR II Version 4.40 Technical Changes and Enhancements ( 5/02) • 29 Caesar.cfg • 1 Calculate actual cold loads • 107 Calculate Actual Cold Loads • 107 Calculation of Fatigue Stresses • 68 Can available space • 41 CANADIAN Z662 • 111 Change Password • 33 Change passwordChange password • 33 Checking the CADPIPE/CAESAR II Data Transfer • 23 Checking the ComputerVision/CAESAR II Data Transfer • 26 Checking the PRO-ISO/CAESAR II Data Transfer • 71 Chopped strand mat • 25, 15 Circumferential (hoop) direction • 67 Weld • 23 Weld joint efficiency • 65 Class 1 Flexibility calculations • 17 Intersection flexibilities • 14 Class 1 Branch Flexibilities • 17, 14 Class 1 Branch Flexibility • 17 Class 1 branch flexibilityClass 1 branch flexibility • 17, 14 Closely Spaced Mode Criteria/Time History Time Step (ms) • 68 Closely spaced mode criteriaClosely spaced mode criteria • 68

Update History

CNode • 33, 38, 129, 46 Coade technical support • 4 COADE Technical Support • 4 Code Compliance • 63, 19 Code Compliance Considerations • 94 Code-calculated • 28 Code-calculated stress • 28 Code-calculated values • 28 Codes • 63 Codes and databases • 12 Codes and Databases • 12 Code-Specific Notes • 99 CODETI • 120 Coefficient of Friction (Mu) • 5, 37 Cold Allowable stress • 65 Load design • 39 Modulus • 75 Spring • 8, 10, 4 Spring element • 4 Sustained • 20 Cold load • 48 Cold Spring • 4 Columns • 44 Fix • 44 Free • 44 COLUMNS • 2, 44 Combining independent piping systems • 123 Combining Independent Piping Systems • 123 Combining static and dynamic results • 31 Combining Static and Dynamic Results • 31 Commands • 1 Compressed formatting • 2 Computation Control • 2, 3 Computation controlComputation control • 3 Computational interfaces • 96, 97 Computational Interfaces • 96 Computed Mass Flow rate • 98 Computed mass flowrate • 94, 98 Computed Mass Flowrate (Vent Gas) • 94 Computervision interface • 24, 25 ComputerVision Interface • 24 ComputerVision Interface Prompts • 25 Computervision neutral file • 25, 26 ComputerVision Neutral File • 25 Computervision/CAESAR II data transfer • 26, 30 Conclusion • 93 Condense Connected Rigids • 73

5

Condense Elbows • 73 Condense Tees • 73 Configuration • 1 Program • 7 Spreadsheets • 1 Configuration and Environment • 2, 1, 94 Configure /Setup • 97 Button • 1 Connect geometry through CNodes • 18 Connect Geometry Through Cnodes • 18, 33 Connecting nodes • 18, 33 Conservative cutoff • 67 Constant effort hanger • 12 Constant effort support • 12 Constant Effort Support • 12 Constant force value • 17 Control Parameters • 1 Control information • 75, 76 Control Information • 75 Controlling the Data Export • 106 Controlling the dynamic solution • 3 Controlling the Dynamic Solution • 2, 1 Convergence error • 4 Convert input to new units • 37 Convert Input to New Units • 37 Convolutions • 102 Coordinate prompts • 115 Corroded Cases • 13 Corrosion • 13, 8 Covers • 105 Cpu time used • 1 Crane database • 27, 82 Create a new units file • 35 Create a New Units File • 35 Create table • 22 Create Table • 22 Creating the .FAT Files • 67 Creep rupture design stress value • 74 Creep rupture stress • 65 Critical damping • 69 Cross Section (Section ID) • 8 Cross section area • 19 Crotch Radius • 88 Crotch radius • 23 Current data • 39 Current Data • 39 Current profile • 32

6

Update History

Curve boundary • 49 Curved pipe • 23 Cut long • 4 Cut short • 8, 4 Cutoff See non-conservative, conservative, and optimal • 67 Cyclic frequency • 54 Cyclic reduction factor fields • 75

D Damped harmonics • 49 Damping • 49 Damping (Time History or DSRSS) (Ratio of Critical) • 69 Damping (time history or dsrss) (ratio of critical)Damping • 69 Damping matrix • 49 Damping ratio • 59, 76 Data Files • 2, 14 Set • 2 Data Export to ODBC Compliant Databases • 103 Data Export Wizard • 107 Data matrix interface • 56, 95 Data Matrix Interface • 95 Database Definitions • 27 Database definitionsDatabase definitions • 27 database management • 103 Decomposition Singularity Tolerance • 6, 83 Decomposition singularity toleranceDecomposition singularity tolerance • 6, 83 Default code • 9 Default Code • 9 Default restraint stiffness • 8 Default rotational restraint stiffness • 8 Default Rotational Restraint Stiffness • 8 Default spring hanger table • 28 Default Spring Hanger Table • 28 Default translational restraint stiffness • 8 Default Translational Restraint Stiffness • 8 Defaulting to Z-Axis Vertical • 118 Defaulting to Z-AxisVertical • 118 Defining a Model • 134 Defining Global Restraints - FIX • 46 Delete • 127, 13 Delta x • 3 Delta y • 3

Delta z • 4 Dens • 18 DENS • 18 Densities • 11 Density • 40, 11 Depth-decay function • 35 Description of Alternate Simplified ASME Sect. VIII Div. 2 Nozzle Analysis • 47 Design Factor (Unitless) • 73 Design strain • 25 Design stress • 65 Det Norske Veritas (DNV) • 127 Diagnostics-error review • 11 Diagonal damping matrix • 59 Diagonal stiffness matrix • 59 Diameter • 6 Diameter 2 • 22 Diameter field • 6 Diffraction effects • 35 Direction • 11, 13, 24, 37, 43, 45 Directional Combination Method (SRSS/ABS) • 80 Directional combination methodDirectional combination method • 80 DIRECTIVE DATA • 32 Directives • 25 Directory structure • 2 Disable • 31 Disable Undo/Redo Ability • 32 Displaced shape • 22 Displaced Shape • 22 Displacement • 58, 13 Loads • 4 Range • 19 ReportsDisplacement Reports • 30

Vector • 49, 59 Displacement Reports Sorted by Nodes • 30 Displacements • 58 Displaying Element Information • 133 Distance to opposite-side stiffener or head • 52 Distance to Opposite-Side Stiffener or Head • 52, 57 Distance to stiffener or head • 52 Distance to Stiffener or Head • 52, 57 DLF curves • 89 Does the vent pipe have an umbrella fitting (y/n) • 92 Does the Vent Pipe Have an Umbrella Fitting (Y/N) • 92

Update History

Double Sum Method (DSRSS) • 77 Drag coefficient • 42 Drag Coefficient, Cd • 61 Driving frequency • 86 DSN Setup • 103 Duplicate • 128 Duplicate dialog box • 128 Dx • 3 DX • 3 DX, DY, DZ • 25, 32 DXF AutoCAD Interface • 4 Dy • 3 DY • 3 Dynamic Analyses • 62 Analysis input • 2 Control parameters • 1 Displacement criteria • 86 Earthquake • 24 Earthquake loading • 116 Equation of motion • 49 Example input textDynamic Example input text • 31

Input • 1 Input processor • 47 Load • 3 Load factor • 49, 54, 64, 97, 102 Load factor spectrum • 54 Loads • 49 Problem • 49 Dynamic Analysis Input • 2 Dynamic Analysis Overview • 3 Dynamic control parameters • 47 Dynamic Control Parameters • 47 Dynamic Example Input Text • 31 Dz • 4 DZ • 4

E Earthquake Effects • 3 Load • 54 Load magnitudes • 24 Loads • 116 Spectrum • 71 Static load cases • 24 EDIM • 2, 31 Eff • 72 Eff, cf, z • 40 Eff, Cf, z • 40

7

Effective ID • 20 Efill • 27 EFILL • 2, 27 Egen • 29 EGEN • 2, 29 Eigensolution • 54 Eigensolver algorithm • 54 Eigenvalue • 54 Eigenvalues • 82 Elastic Modulus • 75 ModulusElastic Modulus • 41

Elastic analyses of nozzles • 46 Elastic Modulus • 41, 95 ELEM • 2, 26 ElemBuilding elements Elem, efill, egen, edim • 26 Element Duplication • 128 List • 125 Offsets • 5 RotationDelete • 127 Element Cosines • 4 Element Direction Cosines • 4 Element information Displaying • 133 Element Length • 4 Element Offsets • 5 Elevation • 29 Elevation table entry • 27 Enable Advanced Element Sort • 28 Enable Autosave • 32 Enable Data Export to ODBC-Compliant Databases • 28 End connection information • 37 End Connection Information • 37 Ending frequency • 8 Ending Frequency • 8 Endurance limit • 49 Entity information • 17 Equation for pipe under complete axial restraint • 75 for stress • 75 Equipment vibration • 3 Equivalent wind pressure • 27 Error code definitions • 18 Error Code Definitions • 16 Estimated Number of Significant Figures in Eigenvalues • 82

8

Update History

Evaluating vessel stresses • 44 Evaluating Vessel Stresses • 44 Example • 25, 28, 31, 36, 42, 44, 46, 47, 49, 51, 53, 97, 98 EXAMPLE • 19 Example 1 • 97 Example 2 • 98 Example Problem of a Multiple Load - Case Spring - Hanger Design • 45 Example problem of a multiple load-case springhanger design • 45 Example transfer • 33 Example Transfer • 33 Examples • 33, 36, 47, 49, 51, 53 Excel • 103 Excitation Frequencies • 8 Exclude f2 from UKOOA Bending Stress • 26 Exe files - required • 2 Existing file to start from • 36 Existing File to Start From • 36 Exit pipe end flow conditions • 99 Exp. Coeff. • 41 Exp. coeff.Expansion Coefficient • 41 Expansion Case allowable stress • 75 Coefficient • 75 Stress • 75, 19 Stress allowable • 74 Stress range • 19, 20 Expansion joint design notes • 102 Expansion Joint Design Notes • 102 Expansion joint end-types • 103 Expansion Joint Modeler • 97 Expansion Joint Modeler - Expansion Joint Database • 100 Expansion Joint Modeler - From / To Nodes • 99 Expansion Joint Modeler - Hinge/Pin Axis • 99 Expansion Joint Modeler - Modeler Results • 100 Expansion Joint Modeler - Overall Length • 100 Expansion Joint Modeler - Tie Bar Plane • 99 Expansion Joint Modeler Notes • 101 Expansion Joint Styles • 103 Expansion joints • 28, 19, 113 Database • 28 Model • 97, 101 Modeler • 97, 101 Styles • 103 Expansion Joints • 28, 19, 100, 7

Expansion joints and rigids • 133 Expansion Joints and Rigids • 133 Expansion jointsExpansion joints • 7 Exponential format • 4 Extended Operating conditions • 8, 10 Range • 39 External interface • 2 Extracted • 3

F Fac • 40, 75 FAC • 40 Factor • 23, 31 Fatigue Curve data • 79 Cycle • 68 Evaluations • 79 Factor • 68 Fatigue Analysis of Piping Systems • 56 Fatigue Analysis Using CAESAR II • 54 Fatigue Basics • 55 Fatigue Capabilities in Dynamic Analysis • 65 FDBR • 122 Fiberglass reinforced plastic • 11, 15, 114 Fiberglass Reinforced Plastic (FRP) • 11 File Name • 27, 72 File Sets • 2, 1 Files -Clean up • 2 Files-accounting • 8 Fillet • 23 Fillet weld • 79 Filter Out Elements Whose Diameter is Less Than • 28 Final CAESAR II data • 22 Find Distance • 85 Find Element • 85 Finite length expansion joints • 19 Finite Length Expansion Joints • 19 Fitting Flexibility factor • 24 Outside radius • 23 Thickness • 16 Fitting Outside Radius • 88 Fitting Thickness • 16, 93 Flange database • 82 Flange leakage and stress calculations • 9 Flange Leakage and Stress Calculations • 9 Flanged ends • 82

Update History

Flexibility Analysis • 75 Factor • 24, 11, 15 Matrix • 19 Orientation • 51 Fluid Bulk modulus Fluid Bulk modulus • 97

Cutoff • 64 CutoffFrequency Cutoff • 67

Frequency Array Spaces • 85 Frequency Cutoff (HZ) • 67 Frequently Asked Questions • 149 Friction Angle variationFriction

Density • 13, 97 Hammer • 6 Loads • 32 Fluid Bulk Modulus • 97 Fluid Density • 13, 97 Fn • 68 Force • 11, 22, 37, 59 Orthogonalization after convergence • 84 Sets • 59 Spectrum • 6 Spectrum analysis Force

Angle variation • 5

Spectrum analysis • 54

Friction Angle Variation • 5 Friction Normal Force Variation • 5 Friction Slide Multiplier • 5 Friction Stiffness • 4 From • 2 FRP AlphaFRP

Spectrum name • 21 Force Consistent Bend Materials • 28 Force Orthogonalization After Convergence (Y/N) • 84, 85 Force orthogonalization after convergence (y/n)Force Orthogonalization after convergence • 85 Force response spectrum definitions • 21 Force Response Spectrum Definitions • 21 Force set # • 24, 37 Force Set # • 24, 37 Force Spectrum Name • 21 Forces • 59, 102 Forces and moments • 59 Forces and Moments • 59 Forces at elbows • 6 Forces, moments, displacements • 134 Forces, Moments, Displacements • 134 Free Anchor/restraint at node • 47 Code • 47 End connections • 37 Free Anchor/Restraint at Node • 47 Free Code • 47 Free End Connections - FREE • 37 French petrochemical code • 20 Frequency Array spacesFrequency Array spaces • 85

9

Coefficient • 37 Normal force variationFriction Normal force variation • 5

Restraint stiffness • 4 Slide multiplierFriction Slide multiplier • 5

Stiffness factor • 63 StiffnessFriction Stiffness • 4

Alpha • 26

Coefficient of thermal expansion • 117 Data • 2 Laminate type • 25 Modulus of elasticityFRP Modulus of elasticity • 26

Pipe densityFRP Pipe density • 26

Pipe propertiesFiberglass reinforced plastic • 24 Property data fileFRP Property data file • 25

Ratio of shear modulus/emod axial • 117 FRP Alpha (e-06) • 26 FRP Analysis Using CAESAR II • 85 FRP Coefficient of Thermal Expansion (x 1,000,000 ) • 117 FRP flexibilities • 24 FRP Laminate Type • 25, 117 FRP Modulus of Elasticity • 26 FRP Pipe Density • 26

10

Update History

FRP Pipe Properties • 24 FRP Property Data File • 25 FRP Ratio of Shear Modulus/Emod Axial • 117 FRP sif • 24 Ftg ro • 23

Grinnell springs • 39 Group modal combination method • 68 Grouping Method • 75 Grouping method Grouping method • 75 Guide • 34

G

H

G • 18 Gap • 36 Gas-specific heats • 91 General notes • 15 General Notes • 15 General Notes for All Codes • 94 General properties • 13 General Properties • 13 Generation of the CAESAR II configuration file •1 Generation of the CAESAR II Configuration File • 2 Generic database • 82 Generic Neutral Files • 74 Generic neutral filesGeneric neutral files • 74 Geninc • 30 GENINC • 30 Genincto • 30 GENINCTO • 30 Genlast • 30 GENLAST • 30 Geometry Directives • 18 Geometry directivesGeometry directives • 18 German 1991 database • 67 German 1991 Database • 67 Gimbal • 104 Global Editing • 127 Level • 45 Load vector • 17 Stiffness matrix • 12 X direction • 3 Y direction • 3 Z direction • 4 Global Coordinates • 86, 115 Global restraints - fix • 46 Gram-schmidt orthogonalizations • 84 Graphics updates • 8 Graphics Updates • 8 Gravitational acceleration constant • 24 Gravitational loading • 116 Gravity loads - gloads • 51 Gravity Loads - GLOADS • 2, 51

Hanger Algorithm • 12 Auxiliary data field • 32 Data • 106 Default restraint stiffnessHanger Default restraint stiffness • 8

Design • 10 Design algorithm • 11 Design control dialog • 12 Design control spreadsheet • 44, 106 Hot loads • 10 Run control spreadsheet • 39 Sizing algorithmFiles CompatibilityFiles

Compatibility • 10 Table • 39 Travel • 11 Type restraint • 35 Hanger available space • 41 Hanger Data • 40, 45, 106, 111 Hanger Default Restraint Stiffness • 8 Hanger Sizing Algorithm • 10 Hanger Table • 39, 110 Hanger/Can Available Space • 41 Hangers • 37, 133 Hangers/nozzles • 22 Hangers/Nozzles • 22 Harmonic • 3 Analysis • 49, 86, 27 AnalysisHarmonic Analysis • 49

Displacements • 13 Equation • 49 Forces and displacements • 11 Load • 86 Load vector • 49 Method • 3 Harmonic Analysis • 8, 49 Harmonic Displacements • 13 Harmonic Displacements at Compressor Flange • 14 Harmonic Forces and Displacements • 11

Update History

HarmonicHarmonic Profile • 3 Header Pipe Outside Diameter • 91 Header Pipe Wall Thickness • 91 Header stress intensification • 28 Help screen • 4 Help screens and units • 2 Help Screens and Units • 2 Highlight • 134 Highlights • 22, 134 Hinged • 104 Hoop Direction • 65 Elastic modulus • 26 Modulus • 11 Stress • 75 Stress value • 14 Horizontal thermal bowing tolerance • 20 Horizontal Thermal Bowing Tolerance • 20 Horizontal threshold value • 20 Hot Allowable stress • 67 Hanger loads • 47 Load • 39, 10 Load design • 39 Modulus • 75 Sustained • 20 How to Use the CAESAR II / LIQT Interface • 96 How to Use the CAESAR II / PIPENET Interface • 101 Hydrodynamic (Wave and Current) Loading • 30 Hydrodynamic loads • 32

I ID manifold piping • 97 ID Manifold Piping • 97 ID of relief valve orifice • 90 ID of Relief Valve Orifice • 90 ID of relief valve piping • 90 ID of Relief Valve Piping • 90 ID of vent stack piping • 90 ID of Vent Stack Piping • 90 ID relief exit piping • 97 ID Relief Exit Piping • 97 ID relief orifice or rupture disk opening • 97 ID Relief Orifice or Rupture Disk Opening • 97 ID supply header • 97 ID Supply Header • 97 Idealized

11

Allowable stress envelope • 68 Identical results • 1 IEEE 344-1975 • 74 IGE/TD/12 • 126 IGE/tD/12 code • 8, 18, 79 Ignore Spring Hanger Stiffness • 7 Implementation of Macro-Level Analysis for Piping Systems • 78 Importance factor • 24, 27 Impulse • 6 Impulse Impulse profile • 6 INC • 27, 29, 32, 36, 38, 50, 52 Include Missing mass components (y/n)Include Missing mass components • 79

Piping input files • 123 Pseudostatic (anchor movement) componentsInclude Pseudostatic (anchor movement) components • 78

Include Additional Bend Nodes • 28 Include Missing Mass Components (Y/N) • 79 Include Pseudostatic (Anchor Movement) Components (Y/N) • 78, 79, 80 Include Spring Stiffness in Hanger OPE Travel Cases • 7 Included force • 64 Included mass • 64 Including Structural Models • 124 Including the Spring Hanger Stiffness in the Design Algorithm • 13 Inclusion of Missing Mass Correction • 49 Incmatid • 30 INCMATID • 28, 30 Incmatid Incmatid • 28 INCMATID_EDIM • 32 Incore Numerical Check • 5 Incore numerical checkIncore numerical check • 5 Increment • 27, 29, 9, 12, 14, 25, 44 Incsecid • 28, 30 INCSECID • 28, 30 Incto • 28 INCTO • 28, 30, 32, 36, 38, 50, 53 Incto Incto • 28 Independent shock • 74 Independent support motion • 54, 78 Independent support motion applications Independent support motion applications • 54 Independent support motion load cases • 80

12

Update History

Inertia coefficient • 42 In-plane stress intensification • 28 Input Data cells • 2, 63 Dynamic • 14 Echo • 130 Fields • 1 GraphicsControl Keys • 131

Soil • 14 Specifying Hydrodynamic Parameters in CAESAR II • 39 Static • 14 Structural • 14 Input items optionally effecting sif calculations • 23 Input Items Optionally Effecting SIF Calculations • 23 Input listing • 130 Input plotting • 131 Input Plotting • 131 INSECID • 32 Insert • 13 Insert Element • 86 Insert weldolets • 23 Installation directory • 1 Installed load • 11 Installed load case • 11 Installed Load Case • 11 Installed weight • 12 Insul thk • 8 Insul Thk • 8 Insulation • 8 Insulation density • 12 Insulation Density • 12 Insulation Units • 30 Interfaces • 1, 2, 1 Interfaces added • 12 Interfaces Added • 12 Intergraph Data • 49 Interface • 30 Intergraph Data After Bend Modifications • 56 Intergraph data after element sort • 47 Intergraph Data After Element Sort • 47 Intergraph data after tee/cross modifications • 48 Intergraph Data After TEE/Cross Modifications • 48 Intergraph data after valve modifications • 49

Intergraph Data After Valve Modifications • 49 Intergraph interface • 26 Intergraph Interface • 26 Intermodal correlation coefficient • 76 Interpolation parameters • 5 Intersection model • 22 Intersections • 23 Introduction • 1 Iso • 4 Ixx • 19 Iyy • 20

J Jacobi Sweep Tolerance • 83 Jacobi sweep toleranceJacobi sweep tolerance • 83 Jacobus • 74 JIS nominal pipe od • 6 JIS pipe schedule • 7 Joint endtypes • 101

K Kaux • 123 Keulegan-carpenter number • 35 K-Factor • 18 Kinematic viscosity • 42 Korean 1990 database • 71 Korean 1990 Database • 73 Ksd. (Factor) (Unitless) • 78

L Labels • 22 Laminate Type • 25, 15 Last • 28, 30, 36, 39, 53 LAST • 24, 28, 30, 36, 39, 50, 53 Lateral force • 24 Length of manifold piping • 97 Length of Manifold Piping • 97 Length of relief exit piping • 97 Length of Relief Exit Piping • 97 Length of the vent stack • 90 Length of the Vent Stack • 90 Liberal Expansion Stress Allowable • 14, 116 Liberal Stress Allowable • 115 Lift coefficient • 42 Lift Coefficient, Cl • 62 Lift force • 32 LIM • 34 Line

Update History

Pressure Line Pressure • 90

Temperature Line Temperature • 90

Line Pressure • 90 Line Temperature • 90 Liners • 105 LIQT interface • 96 LIQT Interface • 96 LIQT nodes • 96 Liquid vent system • 96 List • 54 LIST • 2, 54 List option • 125 List utility • 123 List/ Edit Facility • 125 List/edit facility • 125 Listing • 14 Load Duration • 76 Forcing frequency • 69 Profiles • 59 Range • 39 Load case • 31 Load Case • 31 Load Case Template • 28 Load Cycles • 10 Load Duration (Time History or DSRSS Method) (Sec.) • 69 Load duration (time history or dsrss method)Load Duration • 69 Load vector Applied • 49 Loads • 48 Local Coordinates • 128 Local flexibilities • 14 Local stresses • 44 Log file • 26 Longitudinal Stress • 14 Longitudinal weld joint efficiency • 65 Loop closure tolerance • 115 Loop Closure Tolerance • 19 Loop closure toleranceLoop closure tolerance • 19 Lumped Masses • 43

13

M Macro-Level Analysis • 77 Make units file • 34 Make Units File • 34 Manifold pipe end flow conditions • 99 Manifold piping • 97 Marine growth • 35 Marine Growth • 62 Marine Growth Density • 62 Mass • 43 Flowrate • 94, 98 Matrix • 49 Matching Pipe Outside Diameter • 95 Material - Add • 38 - Delete • 38 - Edit • 39 Coefficient of thermal expansion • 18 Database • 2 DatabaseMaterial Database • 38

Density • 18 Files • 25 ID number • 17 IdentificationMaterial Identification • 17

Name • 10 Properties • 10 Material - Add • 38 Material - Delete • 38 Material - Edit • 39 Material Database • 38 Material Fatigue Curves • 79 Material Identification - MATID • 2, 17 Material Name • 10 Material Properties • 10, 7 Materials • 10, 105 Matid • 17 MATID • 17, 28, 30, 32 Matid Matid • 28, 30 Max. no. of Eigenvalues calculated • 64 Max. No. of Eigenvalues Calculated (0-Not used) • 64 Maximum Shear theory • 11 Maximum allowed bend angle • 19 Maximum Allowed Bend Angle • 19 Maximum allowed travel limit • 43

14

Update History

Maximum Allowed Travel Limit • 43, 109 Maximum Anchor Node • 28 Maximum Pressure • 96 Maximum table frequency • 21 Maximum Table Frequency • 21 Mechanical resonances • 86 Member weight load • 50 Memory Allocated • 31 Memory allocatedMemory allocated • 31 Menu Accounting • 1 Items • 1 Miche limit • 32 Micro-Level Analysis • 71 Mill tol % • 8 -Mill Tol % • 8 Mill tolerance • 8 Mini-Level Analysis • 75 Minimum Allowed bend angle • 19 Angle to adjacent bend • 19 Temperature curve • 40 Wall mill toleranceMinimum Wall mill tolerance • 6

Yield strength • 74 Yield stress • 74 Minimum Allowed Bend Angle • 19 Minimum Anchor Node • 28 Minimum Angle to Adjacent Bend • 19 Minimum Temperature Curve (A-D) • 40 Minimum Wall Mill Tolerance (%) • 6 Miscellaneous • 30, 9 Changes • 12 Data group • 87 Modifications • 8 Miscellaneous Changes • 12 Miscellaneous Data Group #1 • 87 Miscellaneous Modifications • 8 Miscellaneous Processors • 2, 1 Missing Mass • 64 Mass combination methodMissing Mass combination method • 79

Mass correction • 79 Mass ZPAMissing Mass ZPA • 3

Missing Mass Combination Method (SRSS/ABS) • 79 Missing Mass ZPA • 3

Miter points • 16 Miter Points • 16, 95 Miters • 16 Modal Combination methodModal Combination method • 75

Combinations • 74 Components • 74 Extraction • 49 ExtractionModal Extraction • 54

Modal Combination Method (GROUP/10%/DSRSS/ABS/SRSS) • 75 Mode shape • 54, 59, 86 Model - expansion joint menu • 97 Model Definition Method • 11 Model Rotation • 29, 73 Model rotation, panning, and zooming • 131 Model Rotation, Panning, and Zooming • 131 Model Tees as 3 Elements • 29 Modeling friction effects • 17 Modeling Friction Effects • 17 Modeling techniques • 1 Modes of vibration • 54 Modified theories • 35 Modifying mass lumping • 43 Modulus of elasticity • 10 Modulus ratio • 75 Moments • 59, 102 Morrison's equation • 32 Movement capability • 102 Movement Capability • 102 Mu • 37 Multi-degree-of-freedom system • 69 Multiple load case design • 45, 112 Multiple Load Case Design • 45 Multiple Load Case Design Options • 112

N n1 • 24, 27, 29, 35, 36, 37, 50, 52 N1 • 24, 27, 29, 35, 36, 37, 50 Name • 39, 3, 20, 16 Name of the converted file • 37 Name of the Converted File • 37 Name of the input file to convert • 37 Name of the Input File to Convert • 37 Name of the units file to use • 37 Name of the Units File to Use • 37 Natural frequency • 54

Update History

NAVY 505 • 113 Neutral file • 95 Neutral file interface • 75 Neutral file transfer • 2 New File • 4 New Password • 33 New units file name • 36 New Units File Name • 36 Nfill • 23 NFILL • 2, 23 Ngen • 24 NGEN • 2, 24 No rft/wlt in reduced fitting sifs • 17 No RFT/WLT in Reduced Fitting SIFs • 17 No. hangers at location • 44 No. Hangers at Location • 44 No. of Hanger - Design Operating Load Cases • 107 No. of hanger-design operating load cases • 107 No. of Iterations Per Shift (0 - Pgm computed) • 84, 85 No. of iterations per shift (0-pgm computed) • 84 No. to Converge Before Shift Allowed (0 - Not Used) • 84 No. to converge before shift allowed (0-not used) Number to converge before shift allowed • 84 Nodal coordinate data • 94 Nodal Coordinate Data • 94 Nodal displacements • 17 Node • 19, 15, 33, 38, 22, 37, 46 Number • 2, 15, 28, 33 Numbers • 134 NODE • 2, 22 Node Increment • 86 Node number • 2 Node Number Increment • 28, 73 Node Numbers • 134 NODEINC • 25 Nodes • 21, 129 Nodes in space • 22 Nominal pipe OD • 6 Nominal pipe schedules • 6 Non-conservative cutoff • 67 Nonlinear Code complianceNonlinear Code compliance • 19

Piping code compliance • 19 Restraint • 19 Nonlinear Code Compliance • 19

Nonlinear restraints • 20 Norwegian (TBK 5-6) • 121 Notes on Occasional Load Cases • 23 Nozzle Auxiliary data field • 32, 49, 53 Flexibilities • 32 Nozzle diameter • 52 Nozzle Diameter • 52, 54, 56 Nozzle flexibility - WRC 297 • 49 Nozzle Flexibility - WRC 297 • 49 Nozzle node number • 51 Nozzle Node Number • 51, 54, 56 Nozzle wall thickness • 52, 54 Nozzle Wall Thickness • 52, 54 Nozzles • 49, 133 Nuclear Regulatory Guide 1.92 • 74 Number • 39 Number formats • 4 Number of points in the table • 22 Number of Points in the Table • 22

O Occasional Load factor • 10 Load factorOccasional Load factor • 10

Occasional Load Factor • 10 Ocean currents • 34 Ocean Currents • 34 Ocean Wave Particulars • 31 ODBC • 103, 106 ODBC Compliant Database Name • 29 Off-diagonal coefficients • 6 Offsetting • 4 On-diagonal coefficient • 6 OPENGL Switch • 21 Operating Analysis • 19 Case • 11 Case vertical displacement • 11 Load field • 44 Loads • 39, 44 Pressure • 78 Temperature • 75 Thermal cases • 45 Operating Case • 11 Operating Load • 44 Optimal cutoff • 67 Ordinate • 21 Ordinate Interpolation • 18

15

16

Update History

Ordinate Type • 17 Orient • 36 ORIENT • 2, 36 Orienting a Piping model to Z-axis Vertical • 118 Orienting a Piping Model to Z-Axis Vertical • 119 Orienting a Structural Model to Z-Axis Vertical • 121 Orienting a Structural Model to Z-Axis Vertical. • 121 Orienting an Equipment Model to Z-Axis Vertical. • 122 Orienting an Equipment Model to Z-Axis VerticalOrienting an Equipment Model to ZAxis Vertical • 122 Orifice flow conditions • 99 Orifice Flow Conditions/Exit Pipe End Flow Conditions/Manifold Pipe End Flow Conditions • 99 Ortho • 4 Orthogonal • 37 Other Global Coordinate Systems • 129 Other Notes on Hanger Sizing • 13 Out-of-core eigensolver (y/n) • 85 Output • 14 Processor • 59 Output from the liquid relief load synthesizer • 98 Output From the Liquid Relief Load Synthesizer • 98 Output Reports by Load Case • 30 Output reports by load caseOutput Reports by load case • 30 Output Table of Contents • 30 Output table of contentsOutput Table of contents • 30 Overview • 1, 2 Overview of CAESAR II Interfaces • 2

P Pad Thickness • 88 Pad thk • 23 PCF Interface • 72 PD 5500 Nozzles • 55 PD 5500 radio button • 55 PD/4t • 14 PDMS • 74 Peak pressure • 78

Percent of iterations per shift before orthogonalization • 85 Percent of Iterations Per Shift Before Orthogonalization • 85 Period • 54 Phase • 12, 14 Phase angle • 12, 14 Pipe Density • 10, 11 Element exposed area • 27 Element spreadsheet • 5, 59, 60, 61, 63, 7 Outside diameter • 52 Schedules • 7 Section data • 6 Size • 27 Spreadsheet • 97, 106 Pipe Density • 11 Pipe Section Data • 6 Pipe Stress Analysis Coordinate Systems • 131 Pipe Stress Analysis of FRP Piping • 70 Pipenet interface • 100, 102 PIPENET Interface • 100 Pipes • 21 Piping Codes • 63 Element data • 42 Materials • 10 Screen reference • 1 Size specification Piping Size specification • 27

Spreadsheet • 63 Spreadsheet data • 2 System model • 49 Piping Element Data • 42 Piping Materials • 10 Piping Screen Reference • 2, 1 Piping Size Specification (ANSI/JIS/DIN/BS) • 27 Piping Spreadsheet Data • 2 Plant space • 74 Plastic pipe • 11 Plate • 103 Plot colors • 21 Plot Colors • 21 Plot screen • 1 Point loads - load • 48 Point Loads - LOAD • 2, 48 Pois • 18 POIS • 18 Poisson's ratio • 26, 10, 11, 75, 18

Update History

Poisson's Ratio • 40 Poisson's ratioPoisson's ratio • 40 Polar moment of inertia • 20, 55 Practical Applications • 85 Predefined El centro • 54 Hanger data • 48 Nuclear Regulatory Guide 1.60 • 54 Uniform building code • 54 Predefined Hanger Data • 48 Pressure • 10 Peaks • 86 Pulses • 86 Rating • 103 Stiffening • 3 Stress multiplier • 23 Thrust • 7 Pressure Rating • 103 Pressure stiffening • 3 Pressure Variation in Expansion Cases • 17 Pressures • 10 Pricing factors • 1 Primary membrane stress • 44 Primary stress index • 23 Print alphas and pipe properties • 113 Print Alphas and Pipe Properties • 113 Print forces on rigids and expansion joints • 113 Print Forces on Rigids and Expansion Joints • 113 Printer/listing files • 2 Printing an input listing • 130 Printing an Input Listing • 130 Procedure to Perform Elastic Analyses of Nozzles • 46 Program support / user assistance • 3 Program Support / User Assistance • 3 PRO-ISO example transfer • 68 PRO-ISO Example Transfer • 68 PRO-ISO interface • 56 PRO-ISO Interface • 64 PRO-ISO/CAESAR II data transfer • 71 Prompted Autosave • 32 Prompted Auto-SavePrompted Autosave • 32 Proof stress • 65, 74 Pseudostatic Combination methodPseudostatic Combination method • 79

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Displacement • 54 Hydrodynamic loading • 32 Responses • 79 Pseudostatic (Anchor Movement) Comb. Method (SRSS/ABS) • 79 Pseudo-Static Hydrodynamic Loading • 32 Publication dates • 63 Pulsation • 3 Pulsation loads • 86 Pulsation Loads • 86 Pulse table generator • 21 Pulse table/dlf spectrum generator • 54 Pvar • 78

R R1 • 22 R2 • 22 Radius • 14 Random • 3 Random Random profile • 3 Range • 134, 20 Range Interpolation • 17 Range Type • 17 Ratio of gas-specific heats gas constant • 91 Ratio Shear Mod Emod • 26 Ratio shear modulus • 26 Rayleigh damping • 69 RCC-M Subsection C and D • 119 Reduced Intersection • 16 Reduced intersectionReduced intersection • 16 Reducers • 20 References • 42, 52, 93 Refractory lined pipe • 8 Reinforcing pad • 23, 52 Relief Exit piping • 97 Valve • 6 Relief load Analysis • 89 Relief Load Synthesis for Gases Greater Than 15 psig • 89 Relief load synthesis for gases greater than 15 psigRelief load Synthesis • 89 Relief load synthesis for liquids • 96 Relief Load Synthesis for Liquids • 96 Relief Valve or Rupture Disk • 97 Relief valve or rupture disk Relief

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Update History

Valve • 97 Relief Valve Thrust Load Analysis • 89 Relief valve thrust load analysisRelief Valve thrust load analysis • 89 Remove HA Elements • 28 Remove Password • 33 Remove passwordRemove password • 33 Replace • 13 Reset plot • 132 Reset Plot • 132 Resetting element strong axis - angle, orient • 34 Resetting Element Strong Axis - ANGLE, ORIENT • 34 Re-setting loads on existing spring hangers • 48 Re-setting Loads on Existing Spring Hangers • 48 Response Spectra / Time History Load Profiles • 16 Response spectra profiles • 16 Response spectrum • 20, 54 Response Spectrum / Time History Profile Data Point Input • 20 Restrained weight • 47, 10 Restrained weight case • 10 Restrained Weight Case • 10 Restraint Auxiliary field • 33 Loads • 86 Type • 33 Restraints • 32, 133 Re-use last eigensolution • 73 Re-use Last Eigensolution • 73 Review existing units file • 34 Review Existing Units File • 34 Reynolds number • 35 Rigid Element application • 2 Elements • 18, 113 Fluid weightRigid Fluid weight • 2

Insulation weightRigid Insulation weight • 2

Material weightRigid Material weight • 2

Modes • 64 Rod • 43 Support displacement criteria • 43 Y restraints • 47 Rigid Element Application • 2

Rigid Elements • 18 Rigid Fluid Weight • 2 Rigid Insulation Weight • 2 Rigid Material Weight • 2 Rigid Support Displacement Criteria • 43, 109 Rigids/bends • 21 Rigids/Bends • 21 Rod Increment (degrees) • 4 Rod increment (degrees)Rod increment • 4 Rod Tolerance (degrees) • 4 Rod tolerance (degrees)Rod tolerance • 4 Rotate • 127 Rotating equipment report updates • 8 Rotating Equipment Report Updates • 8 Rotation rod • 35 Rotational option • 114 Rotations • 132 Run control data spreadsheet • 45 Rupture disk • 97 Rupture disk opening • 97 Rx (cosx, cosy, cosz) or rx (vecx, vecy, vecz) • 34 RX (cosx, cosy, cosz) or RX (vecx, vecy, vecz) • 34 Rx, ry, or rz • 34 RX, RY, or RZ • 34

S Sc • 65 SC • 65 Schneider • 13, 17 Scratch • 14 SE isometric view • 133 Seam-welded • 8, 18 Seam-Welded • 8, 18 Seawater Data • 42 Secid • 19, 30 SECID • 19, 28, 30 Secid Secid • 28 SECID_EIDM • 32 Section 1-Entity Information • 17 Section 2-Segment Information • 18 Section 3-Final CAESAR II Data • 22 Section ID • 19 Section Identification - SECID • 2, 19 Section identification - secidSection identification - secid • 19 Section modulus calculations • 16 Segment information • 18 Seismic

Update History

Anchor movements • 54 Loads • 54 Spectrum analysisSeismic Spectrum analysis • 54

Zone • 24 Zone coefficient • 24 Set/Change Password • 33 Set/change passwordSet/change password • 33 Setting DefaultsSetting Defaults • 21

Nodes in space • 21 Nodes in spaceNode • 22 Setting Defaults - DEFAULT • 2, 21, 26, 30, 32 Setting Nodes in Space - NODE, NFILL, NGEN • 22 Setting up the spring load cases • 12 Setting Up the Spring Load Cases • 12 Setup option • 127 Sh • 67 SH • 67 Sh fields • 65 Shape • 53 SHAPE • 53 Shear modulus of elasticity • 11, 117, 18 Shft option disabled • 132 SHFT Option Disabled • 132 Shft option enabled • 132 SHFT Option Enabled • 132 Shock displacement • 59 Shock load case • 54 Short range springs • 44 Should caesar ii size the vent stack (y/n) • 93 Should CAESAR II Size the Vent Stack (Y/N) • 93 Show Informational Messages • 86 SIF • 11 SIF / Tee Node Number • 27 SIF at bend • 13 SIFs & tees • 22 SIFs & Tees • 22 SIFs and Stresses • 9 SIFs and stressesSIF • 9 Simplified ASME Sect. VIII Div. 2 Elastic Nozzle Analysis • 48 Single

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Directional restraint • 43 Element insert • 80 Gimbal expansion joint • 104 Hinged expansion joint • 104 Unrestrained expansion joint • 104 Sinusoidal forms • 49 Slipon • 103 Slug flow • 6 Snubbers • 45 Socket Fillet Weld Leg Length • 91 Soil factor • 24 South African 1992 database • 71 South African 1992 Database • 71 Spatial Combination methodSpatial Combination method • 75

Components • 74 Spatial Combination Method (SRSS/ABS) • 75 Spatial or Modal Combination First • 74 Spatial or modal combination firstSpatial Combination method • 74 Special execution parameters • 59, 113, 2 Special Execution Parameters • 113 Specific gravity • 13 Specified Minimum Yield Stress • 75 Spectrum • 3 Spectrum /Time History Profile • 23 Spectrum analysis • 69 Spectrum Analysis • 54 Spectrum analysisSpectrum analysis • 54 Spectrum Time History • 37 Spectrum/time history profile • 23 Spring Design requirements • 10 Forces • 103 Rate • 48, 12 Tables • 39 Spring Design Requirements • 10 Spring Forces • 103 Spring hangers • 48 Spring Rate and Cold Load • 48 Square root of the sum of the squares • 75 Square Root of the Sum of the Squares (SRSS) • 78 Square root of the sum of the squaresSquare root of the sum of the squares • 78 Standard airy wave theory • 33 Standard structural element connections - beams, braces, column • 40

20

Update History

Standard Structural Element Connections - BEAMS, BRACES, COLUMNS • 40 Start node • 12, 14, 25, 43 Start Node • 12, 14, 25, 43 Starting frequency • 8 Starting Frequency • 8 Starting Node Number • 28, 72 Static Earthquake loads • 24 Load case • 62 Load case builder • 27 Load case for nonlinear restraint statusStatic Load case • 62

Output processor • 86 Seismic loadsStatic Seismic loads • 24

Superposition • 20 Thermal criteria • 86 Static Analysis Fatigue Example • 57 Static friction coefficient • 37 Static Load Case for Nonlinear Restraint Status • 62 Static Seismic Loads • 24 Stif • 35 Stiffness • 35, 45 Stiffness Factor for Friction (0.0 - Not Used) • 63 Stiffness factor for frictionStiffness factor for friction • 63 Stiffness matrix • 49 Stokes 5th order wave theory • 30 STOKES Wave Theory Implementation • 34 Stoomwezen • 118 Stop node • 12, 14, 44 Stop Node • 12, 14, 25, 44 Straight pipe • 23 Stream function wave theory • 30 Stream Function Wave Theory Implementation • 34 Stress Calculation • 75 Cycles • 68 Intensification factors • 15, 28 Intensity • 44 Stress < Level 1 • 23 Stress > level 1 • 23 Stress > Level 1 • 23 Stress > level 2 • 23

Stress > Level 2 • 23 Stress > level 3 • 23 Stress > Level 3 • 23 Stress > level 4 • 23 Stress > Level 4 • 23 Stress > level 5 • 23 Stress > Level 5 • 23 Stress intensification factor scratchpad • 9 Stress Intensification Factor Scratchpad • 9 Stress intensification factors (details) • 28 Stress Intensification Factors (Details) • 28 Stress level 1 • 22 Stress Level 1 • 22 Stress level 2 • 22 Stress Level 2 • 22 Stress level 3 • 22 Stress Level 3 • 22 Stress level 4 • 22 Stress Level 4 • 22 Stress level 5 • 22 Stress Level 5 • 22 Stress stiffening due to pressure • 116 Stress Stiffening Due to Pressure • 15 Stress Stiffening Due to Pressure (all codes except IGE/TD/12) • 116 Strong axis moment of inertia • 19, 55 Structural Classification options • 27 Databases • 55 DatabaseStructural Database • 27

Element keywords • 2 Elements • 52 Steel modeler • 1 Structural Database • 27 Structural Databases • 55 Structural Steel Modeler • 2, 1 Structure • 22 Sturm sequence • 80 Sturm Sequence Check on Computed Eigenvalues (Y/N) • 80 Sturm sequenceSturm sequence • 80 Subsonic velocity gas conditionsSubsonic velocity gas • 96 Subsonic vent exit limit Subsonic vent exit • 95 Subspace Size (0-Not Used) • 83 Subspace sizeSubspace size • 83 Supply header • 97 Supply header pipe wall thickness • 98 Supply Header Pipe Wall Thickness • 98

Update History

Supply Overpressure • 97 Supply overpressure Supply overpressure • 97 Sustained Analysis • 19 Stress • 75, 20 Stress limit • 74 Sustained stresses and non linear restraints • 20 Sustained Stresses and Nonlinear Restraints • 20 Swedish Method 1 and 2 • 116 Sy • 74 Sy - Yield Stress at Temperature • 72 Sy data field • 65 System Damping • 69 System Directory Name • 28 System directory nameSystem Directory name • 28

T Tangent intersection point • 15 Tank node number • 54 Tank Node Number • 54 Tapered transitions • 23 Technical discussion of liqt interface • 97 Technical Discussion of LIQT Interface • 97 Technical Discussion of PIPENET Interface • 102 Technical Discussions • 2, 4, 1 Technical notes on caesar ii hydrodynamic loading • 35 Technical Notes on CAESAR II Hydrodynamic Loading • 35 Tee SIF Scratchpad • 86 Temperature • 41, 8 Temperatures • 8 Ten Percent Method • 76 The Right Hand Rule • 129 The Structural Steel Property Editor • 4 Theoretical cold load • 48, 11 Thermal Bowing • 20 Bowing delta temperature • 115 Expansion coefficient • 4, 26, 8, 75, 117 Expansion/pipe weight report • 2 Shakedown • 4 Thermal Bowing Delta Temperature • 115 Thermodynamic Entropy Limit /Subsonic Vent Exit Limit • 95 Thermodynamic entropyThermodynamic entropy • 95

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Thickness 2 • 22 Thicknesses, diameter, length, material number • 134 Thicknesses, Diameter, Length, Material Number • 134 Thrust • 20, 89 Thrust at the end of the exit piping • 98 Thrust at the End of the Exit Piping • 98 Thrust at the end of the manifold piping • 98 Thrust at the End of the Manifold Piping • 98 Thrust at the vent pipe exit • 95 Thrust at the Vent Pipe Exit • 95 Thrust at valve pipe/vent pipe interface • 94 Thrust at Valve Pipe/Vent Pipe Interface • 94 Tied • 104 Tied single expansion joint • 104 Tied universal expansion joint • 105 Time • 22, 59 History analysis • 6, 59, 69 History animationTime History animation • 31

History loads • 97, 102 HistoryTime History analysis • 59

Step • 68 Time History • 59 Time History Animation • 31 Time history load cases • 23 Time history profile data point • 20 Time history profilesTime History load profiles • 16 Time history time step • 68 Title page • 106 Title Page • 106 To • 2 TO • 24, 27, 29, 31, 36, 37, 50, 52 To node number • 2 Toolbar buttons • 1 Tools Accounting • 1 Material database • 38 Multiple job analysis • 9 Topographic factor parameters • 27 Torsional Stiffness • 7 Torsional R • 20 Torsional spring rates • 102 Torsional Spring Rates • 102 Transforming from Global to Local • 148

22

Update History

Transient Load • 54 Load cases • 59 Transient pressure rise on valve closing • 95 Transient Pressure Rise on Valve Closing • 95, 98 Transient Pressure Rise on Valve Opening • 95, 98 Transient pressure rise on valve openingTransient Pressure • 95 Translational Option • 114 Restraint • 36 Stiffness • 101 Translations • 132 Transverse stiffness • 7 T-univ • 105 T-UNIV • 105 Type • 15, 33 Type field • 15

U UBC • 16 UK 1993 database • 74 UK 1993 Database • 74 UKOOA • 11, 125 Ult Tensile Stress • 41 Ultimate tensile strength • 74 Umbrella fitting • 92 Unbalanced pressure force • 3, 86 Underlying Theory • 70 Uniform Building code • 16, 71 Load • 50 Loads-UNIF • 49 Support excitation • 54 Uniform load in g's • 116 Uniform Load in G's • 60, 116, 2, 24 Uniform loads • 59 Uniform Loads • 59 Uniform loads - unif • 49 Uniform Loads - UNIF • 49 Units Conversion Data • 93 Units conversion data • 93 Units Conversion Data • 93 Units File • 5 Units File Name • 28 Units file nameUnits

File name • 28 Units File Operations • 34 Units file operationsUnits File operations • 34 UNITS Specification - UNIT • 2, 14 Units specification - unitUnits Specification - UNIT • 14 Unskew • 127 Untied • 104 Untied universal expansion joint • 104 Update history • 1 Update History • 2, 1 Use FRP Flexibilities • 24 Use FRP SIF • 24 Use Out-Of-Core Eigensolver (Y/N) • 85 Use PD/4t • 14 Use Pressure Stiffening • 3 Use Schneider • 13 Use WRC329 • 13 User ID • 31 User IDUser ID • 31 User-defined • 19 User-Defined • 19 User-defined SIFs anywhere in the piping system • 27 User-Defined SIFS Anywhere in the Piping System • 27 User-defined spectra • 54 Using Local Coordinates • 136 Utilities • 54 UTS - Ultimate Tensile Strength of Material • 72 U-univ • 104 U-UNIV • 104 Ux,uy,uz • 50 UX,UY,UZ • 50

V Valve /Flange database • 27 Pipe/vent pipe interface • 94 Valve Orifice Gas Conditions /Vent Pipe Exit Gas Conditions/Subsonic Velocity Gas Conditions • 96 Valve orifice gas conditions Valve Orifice gas • 96 Valve/flange database • 82 Valve/Flange Database • 18, 82 Valves and flanges • 27 Valves and Flanges • 27 Velocity vector • 49, 59

Update History

Vent Pipe exit • 95 Stack • 93 Vent pipe exit gas conditions Vent Pipe exit gas • 96 Version and job title information • 75 Version and Job Title Information • 75 Vertical Axis • 6 Vessel Diameter • 52 Material number • 53 Node • 49 Node number • 51 Temperature • 53 Type • 56 Wall thickness • 52 Vessel centerline direction cosines • 57 Vessel Centerline Direction Cosines • 57 Vessel centerline direction vector x, y, z • 52 Vessel centerline direction vector X, Y, Z • 52 Vessel Diameter • 52, 57 Vessel Material No. (Optional) • 53, 58 Vessel Node Number • 51, 56 Vessel reinforcing pad thickness • 52 Vessel Reinforcing Pad Thickness • 52, 57 Vessel Temperature (Optional) • 53, 57 Vessel Type - Cylinder (0) or Sphere (1) • 56 Vessel Wall Thickness • 52, 57 Vibrations • 49 View/edit file • 36 View/Edit File • 36 Views • 133 Volume plotting • 133 Volume Plotting • 133 Von Mises theory • 11 Vortex shedding • 27

W Wall thickness • 6 Wall Thickness of Matching Pipe • 95 Wall thickness/schedule field • 7 Wave Data • 41 Theories • 32 Wave Data • 41 Wave Loads • 61 Weak axis moment of inertia • 20, 55 Weight analysis • 47 Weight Units • 29 Weld d (Mismatch) • 89

23

Weld ID • 23, 89 Welded • 103 Wind Effects • 3 Exposure options • 27 Force • 27 Load • 8 Loads • 52, 27 LoadsWind Loads • 27

Pressure • 27 Shape factor • 61, 52, 27 Speed • 27 Wind Loads • 60, 27 Wind Loads - WIND • 2, 52 Wind Shape Factor • 61 Wind/wave loads • 60 Wn • 103 WN • 103 WRC 107 • 5, 46, 8 WRC 107 Updates • 8 WRC 297 • 9 WRC 297 Local Stress Calculations • 9 WRC 329 • 13, 14 WRC-107 Interpolation Method • 5 WRC-107 Version • 5 Wt/sch • 7 Wt/Sch • 7

X X (cosx, cosy, cosz) or x (vecx, vecy, vecz) • 34 X (cosx, cosy, cosz) or X (vecx, vecy, vecz) • 34 X , y, or z • 34 X , Y, or Z • 34 X2, Y2, Z2 • 34 Xrod (cosx, cosy, cosz) or xrod (vecx, vecy, vecz) • 35 XROD (COSX, COSY, COSZ) or XROD (VECX, VECY, VECZ) • 35 Xrod, yrod, zrod • 35 XROD, YROD, ZROD • 35 XSNB, YSNB, ZSNB • 34 XSPR, YSPR, ZSPR • 34

Y Yield

24

Update History

Criteria theory • 11 Strength • 18 Stress • 65 StressYield Stress • 11, 41

Yield Stress • 41 Yield Stress Criterion • 11 YM • 18 Young's modulus of elasticity • 18 Ys • 18 YS • 18

Z Z-Axis Vertical • 19, 118, 15 Zero Period acceleration • 54 Weight rigids • 2 Zero Length Expansion Joints • 19 Zero-length expansion joints • 19 Zooming • 132 ZPA (Reg. Guide 1.60/UBC- G's)/# Time History Output Cases • 71 ZPA time history output cases • 71