General Tool Overview.doc

Recommended Practice: General E-Line Tool Overview

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Alaska Wells Group Recommended Practice: General E-line Tool Overview Authority:

NSU ADW Well Operations Supervisor

Custodian:

NSU ADW Wells Engineer

Scope:

ADW-Wells: Electric Line

Document Document Control Control Specialist Administrator:

Issue Date:

January 5, 2002

Issuing Dept:

GPB Wells Group

Revision Date:

February 28, 2005

Control Tier:

Tier 4

Next Review Date:

October 28, 2010

INTELLECTUAL PROPERTY AND CONFIDENTIALITY NOTICE © 2009 BP America Inc. (for all US copyright notices) All rights reserved. This document contains confidential information, which is the exclusive and proprietary property of BP America Inc. and affiliates. In whole or part, this document or its attachments MAY NOT be reproduced by any means, disclosed or used for any purpose without the express written permission of BP America Inc. or affiliates.

1.0 Purpose/Scope This Section provides information to the Wells Group PE’s on the various e-line logging tools that are commonly utilized on the North Slope. Note: Section 7.0 contains Lessons Learned from the field.

2.0 Definitions ASH – Alaska Safety Handbook PE – Wells Group Production Engineer GPB –Greater Prudhoe Bay DSO – Drill site operator SSV – Surface Safety Valve WOA – Western Operating Area EOA – Eastern Operating Area SWS – Schlumberger Well Services

3.0 General Requirements This section provides information on the various e-line logging tool that are commonly used at GPB and the other fields on the North Slope.

4.0 Key Responsibilities Well Operations Supervisor is:  To designate the person to update manual as necessary to incorporate new policies or procedures. Wells Production Engineers are:  Responsible for identifying and submitting changes to the procedures and methodology based on new technology and new and better ways of performing work.  Update the manual based on changes as a result of Root Cause Investigations.

BP Confidential and © 2009 BP America Inc. Control Tier: 4 – ADW Revision Date: 2/28/2005 Document Number: UPS-US-AK-ADW-WLS-ADW-DOC-00075-4 Print Date: 3/24/2019 PAPER COPIES ARE UNCONTROLLED. THIS COPY VALID ONLY AT THE TIME OF PRINTING. THE CONTROLLED VERSION OF THIS DOCUMENT CAN BE FOUND AT http://eportal.bpweb.bp.com/hse

Recommended Practice: General E-Line Tool Overview

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5.0 Description of Tools Individual equipment has specific capabilities and limitations. Below is a brief description of the basic E-Line equipment used in Prudhoe Bay. Tools are categorized into three groups: Production Logging, Fluid Identification, and Diagnostic Logging. Production Logging tools are typically used for evaluating production contributions. Fluid Identification Tools can differentiate between types of fluids entering the wellbore by measuring fluid properties. Diagnostic Logging Tools allow the PE to diagnose various well problems and remedy these problems by running selected tools downhole to pinpoint the problem areas. Many tools are run simultaneously or independently. The tools requested in the procedure should be run for each individual job. 5.1 Production Logging Tools Flowmeters (Spinners) - Spinners are used to evaluate completion efficiency. Producers and injectors are quantitatively measured for flow by zone or perforated interval. These measurements are correlated to evaluate contributions and flow anomaly. This application makes it possible to determine a profile, diagnose well problems, and obtain reservoir information for optimum production/injection management. Continuous Spinner - Most commonly used, the tool sends a continuous signal to surface equipment. Generally, it is run against the flow for a profile and stationary between perforated intervals or zones. The tool can also detect ''fallback'' and gas jetting in the wellbore. Fullbore Spinner - A variation of the continuous spinner, this tool collapses to fit inside a tubing string. Once in the casing, the tool opens and the impeller blades extend to cover a large portion of the flow area. Generally this tool is used for low to medium flow rate wells. Packer/Basket Spinners - These tools are run into the casing and parked between perforated intervals. Flow is forced by the internal impeller by inflating a packer, or extending metal "leaves'' of the basket. These tools are used in low flow rate wells. 5.2 Fluid Identification Tools Capacitance - (Water hold-up, water-cut, dielectric tools) These tools distinguish water, oil, and gas by measuring the dielectric constant of each fluid flowing past ported tubes, from which the resonant capacitance frequency is measured and recorded. The primary function of capacitance tools is to differentiate between water and hydrocarbons. Fluid Density - Fluid density tools are gamma ray absorption devices that consist of an open cage through which fluids can flow a focused gamma ray source and a detector. The tool operates on the principle that the logarithm of the residual gamma rays at the detector is inversely proportional to the sample density. Gradiomanometer - This Schlumberger tool consists of a differential-pressure measuring device that uses two pressure sensors 2 feet apart. The pressure difference translates directly to a pressure gradient, which then is converted to fluid density. The primary function of gradio tools is to differentiate between gas and liquids, but the tool can sometimes differentiate between water and oil when the boundary between the fluids is abrupt. Gamma Ray - The gamma ray tool measures naturally occurring weakly radioactive materials in the formation. These tend to be concentrated in shales and not sandstones or limestones. The primary function of these tools is to differentiate between sands and shales. Note that radioactive salts can be deposited on the casing in perforated intervals by water production causing an abnormally high gamma ray reading in theses zones. Impedance - Impedance tools measure the impedance or resistivity of the fluids passing their sensors. Because oil and water have very different impedances (water conducts electricity whereas oil is a virtual insulator) the tool can estimate the ratio of oil to water. DEFT is BP Confidential and © 2009 BP America Inc. Control Tier: 4 – ADW Revision Date: 2/28/2005 Document Number: UPS-US-AK-ADW-WLS-ADW-DOC-00075-4 Print Date: 3/24/2019 PAPER COPIES ARE UNCONTROLLED. THIS COPY VALID ONLY AT THE TIME OF PRINTING. THE CONTROLLED VERSION OF THIS DOCUMENT CAN BE FOUND AT http://eportal.bpweb.bp.com/hse

Recommended Practice: General E-Line Tool Overview

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Schlumberger’s main impedance tool and is usually run with a PPROF toolstring when oil/water ratios for different zones are needed. GOST Tool - The GOST is a Schlumberger tool that has optical sensors that can differentiate between gas, water, and oil. Temperature / Differential Temperature Tools - The temperature tool consists of temperature sensitive resistors. The resistor elements are exposed to the fluid flow to provide a quick response. Differential temperature curves are created by the difference of two temperature points in a well. This is accomplished by having two sensors on the tool itself or by using memory equipment to compare two temperature points and calculating a differential temperature. For production logging, the temperature tool can provide a profile of fluid entry or injection into the wellbore. The temperature tool will show a cooling anomaly for gas entry and sometimes a heating anomaly for water entry. It is particularly useful comparing a flowing gradient curve with a shut-in gradient curve. The differential temperature curve accentuates any anomalies in the temperature gradient curve. Pressure Tools - The pressure tool can be helpful in production logging to determine: draw-down across the perforated interval; gradients to determine fluid type in the wellbore; and gas-lift analysis to aid in gas-lift design. This tool is generally held stationary at predetermined depths until the pressure reading has "stabilized." Pulsed Neutron Logging Tools - These tools use an electrical neutron generator that is turned on for very short periods of time, sending a burst of neutrons into the formation through the casing. The neutrons are ''captured'' at different rates by the formation and formation fluids. The capture process emits gamma rays that are picked up by sensors on the tool. Thus, the tool can determine formation fluids behind the casing. Depending on the particular tool, they are used to determine gas, oil, and water production intervals in a well; changes in gas/oil contact; and areas of water breakthrough. These tools are logged slowly across the formation, and sometimes may need logs run on prior surveys to determine changes in GOC, WOC, and under-running of shales. Compensated Neutron Logging Tools - These tools use a chemical neutron source that continuously emits neutrons into the formation through the casing. The neutrons are ''captured'' at different rates by the hydrogen atoms in the formation and formation fluids. The capture process emits gamma rays. The tool has sensors that detect either return neutrons or the resultant gamma rays from collisions with hydrogen nuclei. There are two sensors that are spaced apart on the tool. The two sensors are used to compensate for wellbore effects, giving a "near" and "far" count for Hydrogen atom density. The tool can determine formation fluids, primarily gas, behind the casing. It can identify changing gas saturations because gas has a lower density and therefore a lower hydrogen density than oil or water. These tools are used to determine gas intervals and changes in gas/oil contact. These tools are logged at 30 fpm across the formation, and the log data is then "normalized" in a clean oil zone above the perforations. Sometimes the log data will be compared with logs run on prior surveys to determine changes in the gas/oil contact and gas under-running of shales. Note that gas contact detection is generally not possible in zones that have cement channels. A valid CNL porosity curve cannot be obtained if there is gas in the wellbore. A pump-in is required if there is any potential of gas in the wellbore across the logging interval. CNL data is used on a well by well basis to justify remedial work and on an area or field wide basis to monitor reservoir gas movement, to estimate reserves and reservoir drainage rates, and to justify infill development drilling. BP Confidential and © 2009 BP America Inc. Control Tier: 4 – ADW Revision Date: 2/28/2005 Document Number: UPS-US-AK-ADW-WLS-ADW-DOC-00075-4 Print Date: 3/24/2019 PAPER COPIES ARE UNCONTROLLED. THIS COPY VALID ONLY AT THE TIME OF PRINTING. THE CONTROLLED VERSION OF THIS DOCUMENT CAN BE FOUND AT http://eportal.bpweb.bp.com/hse

Recommended Practice: General E-Line Tool Overview

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5.3 Diagnostic Logging Tools Flowmeters/Spinners - The spinner tool can be used to diagnose a variety of well problems. These include, but are not limited to: gas-lift valve survey; production/injection performance; cross-flow; jetting; fallback; and leak detection in tubing and casing. Temperature/Differential Temperature - Temperature logging has many uses in diagnosing well problems in addition to dynamic production/injection characteristics. In shut-in wells, zones of production or injection can be determined by the departure from the normal thermal gradient. This is useful in finding cement channeling or fracturing in the well. The tool is also useful in determining: gas-lift valve leaks and operating valves; casing or tubing leaks; slipped or leaking packers; temperatures needed for cement design; and wax or paraffin depositing problems. Pressure Surveys - Pressure tools can give helpful information for: gas-lift design; pressure sink areas in a reservoir; and downhole pressure monitoring for fluid pump-in jobs. Gamma Ray - The gamma ray tool can be used diagnostically to find scale deposits in a wellbore. Scale deposits are radioactive ''hot spots,'' so the gamma ray tool can pick them up. Generally, the scale is deposited from the salts in seawater breakthrough. Previously run gamma ray logs may be necessary for reference to note changes in gamma-ray signals. Gamma ray tools may also be used instead of, or in conjunction with, a CCL for tie-in purposes when running additional tools. The gamma ray tool detects the natural radioactivity in the reservoir and can identify clean reservoir sandstone and intermixed shales. Cement Evaluation - Cement evaluation logs are used to diagnose cement problems responsible for gas or water channeling. Cement channels result from ''braided" cement in the primary cement job. Log types including CBL's, CBT's, CET's or USIT's (see descriptions of these logs below) are generally run by the Drilling Department on a new well. Later in a well's life, a channel may develop, and these logs may be run again to determine where the channel exists. This information is necessary to design a cement squeeze program. Cement Bond Log - (CBL) is a sonic tool that checks for casing-to-cement bonding by the acoustic ''ring'' of the casing. Cement Bond Tool - (CBT, Atlas) is a new version CBL. The CBT is also a sonic tool that uses higher frequency pulses than the CBL to improve response. Both the CBL and CBT measure cement bond around the entire casing (i.e., can not pinpoint small channels). Cement Evaluation Tool (CET, Schlumberger) has eight focused transducers that allow the tool to focus on eight separate areas of the casing. Thus, the tool can pick up small areas of pipe with poor cement bonding. This helps in finding channels that may be surrounded by relatively good bonding. SCMT Evaluation Tool (Slim Cement Mapping Tool) Has more receivers than a CBL for more comprehensive 360 degree mapping (every 40 degrees) but slimline when a USIT can't be ran in small tubulars. Ultrasonic Imaging Tool (USIT, Schlumberger) is a new cement and casing evaluation tool that uses a rotating transducer to give 360 deg coverage. The USIT transducer emits focused ultrasonic wave pulses and records casing resonance. The tool is used to evaluate casing corrosion and cement bond. Caliper Logging - Inspection of the mechanical state of casing and tubing is accomplished with calipers. Some of the uses of calipers are to determine tubing or casing damage from: corrosion; erosion; bent, broken, or pinched pipe. They also may be used to profile nipples or other tubulars.

BP Confidential and © 2009 BP America Inc. Control Tier: 4 – ADW Revision Date: 2/28/2005 Document Number: UPS-US-AK-ADW-WLS-ADW-DOC-00075-4 Print Date: 3/24/2019 PAPER COPIES ARE UNCONTROLLED. THIS COPY VALID ONLY AT THE TIME OF PRINTING. THE CONTROLLED VERSION OF THIS DOCUMENT CAN BE FOUND AT http://eportal.bpweb.bp.com/hse

Recommended Practice: General E-Line Tool Overview

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The caliper tool consists of a multi-fingered device that converts the casing or tubing I.D. into a signal that is recorded on the surface. Schlumberger’s DEFT tool (see impedance tool description above) can also be used as a crude caliper because the "cage" for the sensors expands and contracts to maintain contact with the wellbore and these motions are transmitted by the tool. Pipe Analysis Log - (PAL (SWS), VERTILOG (Atlas)) These tools are used to find tubular holes, leaks, or damage. They function by taking electromagnetic measurements of the tubulars. As long as the metals are flawless, the surface readout shows a smooth curve. As the tool passes along a cavity, hole, or pipe thickness change, an induced current is generated, and in turn is recorded by the surface equipment. Borehole Televiewer - This tool is an ultrasonic inspection tool run in a liquid-packed wellbore for tubular inspections. A rotating transducer gives 360 deg coverage with resolution to ''dime'' size. The log gives accurate caliper information after computer processing. Logging speed is extremely slow (less than 5 fpm), and is subject to jerks from deviated wellbores. Noise Logs - Noise logging is applicable to problems either in the wellbore or casing that may produce sounds in the audible range. A microphone tool run inside the well detects the sound. This tool is useful for fluid-movement profiles resulting from leaks or channels, especially behind pipe. Tracer Logs - This logging technique consists of ejection of a dye or radioactive tracer element from a downhole tool into a fluid flowpath. The direction and velocity is then monitored by the tool, indicating fluid flowpaths. This logging technique is useful for: estimating fluid flowrates, points of wellbore entry or exit, channeling, cross flow, and tubular leaks. Video Logs – Real time video logging consists of a small video camera with a light source run on an electro-fiber-optic cable. The video cameras are used for verifying tubing and casing integrity, observing fluid entry, and facilitating wireline fishing operations. Water Flow Logs - Using a modified pulse neutron tool, water flow can be identified. It works in principle similar to a tracer log. The advantage is water only temporarily activated by the PNL tool leaves no radioactive material in the well. Flow can be identified either up or down the well, and inside or outside tubing or casing. Reservoir Saturation Logs - (RST, Schlumberger; Pulse Spectral Gamma Ray Tool (PSGT), Halliburton) The RST tool is used to determine fluid saturations behind casing by analyzing gamma-ray spectrum. The tools will typically measure formation porosity, lithology, and carbon/oxygen ratio. Once the field data is collected, additional computer processing is necessary to determine fluid saturations.

6.0 Key Documents/Tools/References BP Getting HSE Right BP’s Golden Rules of Safety BP Drilling and Well Operations Policy Alaska Safety Handbook North Slope Environmental Field Handbook Wells Group Rigless Operations Manual BP Alaska PE Manual ARCO Alaska Wells Group Policies, Guidelines and Resources Manual

7.0 Lessons Learned from the Field Additional information can be found in TeamLink by referencing the LL tracking number. BP Confidential and © 2009 BP America Inc. Control Tier: 4 – ADW Revision Date: 2/28/2005 Document Number: UPS-US-AK-ADW-WLS-ADW-DOC-00075-4 Print Date: 3/24/2019 PAPER COPIES ARE UNCONTROLLED. THIS COPY VALID ONLY AT THE TIME OF PRINTING. THE CONTROLLED VERSION OF THIS DOCUMENT CAN BE FOUND AT http://eportal.bpweb.bp.com/hse

Recommended Practice: General E-Line Tool Overview

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1) TeamLink #10349, November 2008, Wells EL During or after lateral sections are drilled and other mechanical interventions are required, it is advisable to perform a Jewelry log using a Gamma Ray (Optional), CCL, and a X-Y Caliper to the tool string. The X-Y caliper should be run using "Skids" on the arms and NOT rollers or extended pads. The CCL is designed to pick up changes in metal mass change but more than likely be riding on the low side of the hole or at best partially centered if placed immediately above the X-Y Caliper. The X-Y Caliper will show the window of each lateral and also show other anomalies due to jewelry run during completion. 2) TeamLink Lessons Learned #10440, March 2009, Wells EL When an operation overlaps a crew change especially involving the PE, ensure that all change over notes indicate the scope of the operation and all risks involved. Ensure that all contractor requirements are listed on the form. A Tag is now used to place on the correct valves that indicate the shut in well must not be put on production until all well operations cease on the shut in well. The "Tag-Out" procedure for the valve indicates that prior approval from the E-Line engineer has to be given prior to taking out of test and into production header. All other well operations cease until approval is given by the Slickline engineer or the operator.

Revision Log Revision Date 1/5/2002

Approving Authority R. Steven Rossberg

5/2/2002

R. Steven Rossberg

2/28/05 3/30/2006

Doug Cismoski Jerry L. Bixby

November 24, 2008

Jerry L. Bixby

March 17, 2009

Jerry L. Bixby

August 3, 2010

Andy Kirk

Custodian/ Author

Revision Details

Cismoski/Middendor f Cismoski/Middendor f Jim Moore Wells Operation Supervisor

Original Issue

M. Seward / C. Tzvetcoff M. Seward / C. Tzvetcoff Chris Tzvetcoff

Revision #1 No revisions required. Revised Approving Authority and Custodian. Extended next review date. Changed SOP to RP. Added Section 7.0 and LL 10349 Added LL 10440 to Sect 7.0. Add BP Confidentiality Statement

(or, see attached e-mail Approving Authority signature

) Date

BP Confidential and © 2009 BP America Inc. Control Tier: 4 – ADW Revision Date: 2/28/2005 Document Number: UPS-US-AK-ADW-WLS-ADW-DOC-00075-4 Print Date: 3/24/2019 PAPER COPIES ARE UNCONTROLLED. THIS COPY VALID ONLY AT THE TIME OF PRINTING. THE CONTROLLED VERSION OF THIS DOCUMENT CAN BE FOUND AT http://eportal.bpweb.bp.com/hse