Lean Six Sigma Glossary

Lean Six Sigma

Lean Six Sigma White Belt Training

Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 1

Lean Six Sigma

5S’s: ordered actions used to achieve a clean, well-organized workplace; Sort, Simplify, Sanitize, Standardize, Sustain 6M’s: categories representing the sources of variation (Man, Method, Material, Measurement, Mother Nature, Machine) 7 Wastes: Defects, Over Production, Transportation, Waiting, Inventory/Storage, Motion, Processing Common Cause: used to refer to variation that happens in the same way from worker to worker, hour to hour, lot to lot, etc.; on a control chart, common causes by definition always fall within control limits. See also Special Cause. Control Chart: a graphical tool for monitoring a process and/or for determining where variation lies; control charts show results over time, with +/- 3σ boundaries representing the upper and lower control limits (UCL/LCLs) Control Methods: standard methods implemented during the “control” phase of the DMAIC process include: fix, minimize, standardize, measure and monitor, communicate and audit Controllable Inputs: input variables (x’s) that can be changed to see the effect on Process Output Variables (y’s); sometimes called “Knob” Variables Critical Characteristics (in FMEA): those items which affect customer safety and/or could result in noncompliance to regulations and thus require controls to ensure 100% compliance; these are usually process “settings” such as temperature, time, speed, etc. Critical Inputs: x’s that the tools (FMEA, DOE, SPC,etc.) and significant process knowledge have proved to have a major impact on the variability of the y’s Current Controls (in FMEA): are the mechanisms (for both design and process) which prevent the cause of the failure mode from occurring, or detect the failure mode, should it occur, before the product reaches your “customer”; for example current controls include SPC, inspections, written procedures, training, preventive maintenance and all other activities that ensure a smooth running process Cycle Time (C/T): time that elapses between one product exiting the process to the next product coming out or the time it takes to complete a process step; typically the value-added time. Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 2

Lean Six Sigma

Defect: any error or nonconformance which adds cost without adding value Defective: a part that is not acceptable due to one or more defects Detection (in FMEA): an assessment of the likelihood that the current controls (design and process) will detect the cause (process weakness) of the failure mode, should it occur, thus preventing it from reaching your customer; the customer in this case could be the next operation, subsequent operations, or the end user Discrimination (in MSE): the technological ability of the measurement system to adequately differentiate between measured values for a selected parameter DMAIC: the standard framework for Lean Six Sigma projects/implementations, which stands for “Define, Measure, Analyze, Improve, Control” DOE: Design of Experiment DPMO: Defects Per Million Opportunities DPO: Defect Per Opportunity DPU: Defects Per Unit Experimentation: the manipulation of controllable factors (independent variables) at different levels to see their effect on some response (dependent variable); common methods include: trial-and-error, one-factorat-a-time, full factorial, and fractional factorial External Work: set-up activities which can be performed while the machine (or process) is running; See also Internal Work Failure Modes and Effects Analysis (FMEA): tool used to assess the potential failure modes of a process, and the likely effects of potential failures; developed by NASA to eliminate failures during the planning phase of a project Flow Production: continuous movement of the product or service from start to finish without interruption or storage with the intent to eliminate batch sizing and produce at the smallest possible increment FPY: First Pass Yield; the measure typically referred to as “yield”; the total number of parts that are accepted divided by the total number of parts that were started Gage R&R: Gage Repeatability and Reproducibility, a measure of variation arising from the use of a specific measurement device and/or the operator of the measurement device Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 3 • • • • • • • • • • • • • • •

Lean Six Sigma

Hidden Factory: unintended steps/tasks in a process; rework ICC: IntraClass Correlation, an attribute measurement system evaluation Internal Work: set-up activities that requires the machine (or process) be stopped (see external work) Kaizen: a Japanese term for continuous improvement Kanban: a Japanese word for “signal”; kanban systems are pull systems, which replenish materials only as they are used Kappa: an attribute measurement system which compares how well a judge repeats him/herself and/or how well judges agree Lead Time: average time to manufacture and deliver a product or service, from order receipt to delivery to the customer Mean: parameter used to characterize the “process location” or “center”; average of all data points in sample or population Measurement Error: variation in measurement which can be attributed to variation in the item being measured or to the measurement system itself Moving Range Chart: a chart used when control charting individual data; the moving range is used to estimate the short-term variation which is then compared to the individual value variation MSE: Measurement System Evaluation; identifies and quantifies the different sources of variation that affect a measurement system NEM: Numerical Evaluation of Metrics, evaluation of control chart data to: 1) determine common or special cause or 2) determine where the majority of variation lies; even though NEM uses control charts, it is different from SPC which is focused on ‘monitoring’ a process Noise Inputs: input variables that impact the y’s but are uncontrollable, difficult, or too costly to control; example: environmental variables such as humidity, ambient temperature, etc. Non-Value Added: anything that does not transform the form, fit and or function of a product or service as defined by the customer the first time Occurrence (in FMEA): an assessment of the likelihood that a particular cause will happen and result in the failure mode

Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 4

Lean Six Sigma

• OTED: One Touch Exchange of Dies; a set-up performed by one touch • Pareto Chart: the Pareto principle says that 80% of the problems will arise from 20% of the causes; a Pareto chart tests and/or illustrates this relationship by sorting and displaying metrics in a descending order chart • PMAP: Process Map (not a process flow which does not contain inputs and outputs) • PPM: Parts Per Million (defective) • Process Capability Index: comparison of the Voice of the Process to the Voice of the Customer requirements • Process Dispersion: the standard deviation of f(x), symbolized by “σ”, the Greek letter known as “sigma” • Process Input Variables: process inputs can be categorized as controllable, critical, noise, or standard operating procedures • Process Location: the mean or average of f(x), symbolized by “μ”, the Greek letter known as “mu” • Pull Material System: a method of controlling the flow of resources by replacing what has been consumed • Pure Waste: weak process that adds no value and is not required by the customer • Queue Time: time a product waits between the value-added process steps; if inventory exists between process steps, can be approximated by dividing the inventory by customer demand for a time frame • R Chart: Range Chart, also called the “within” chart as the points on the chart represent within group variation; this control chart is , used to display change within subgroups; the R chart for a set of data must be “in control”, more technically defined as “stable’, to be able to use an X-bar chart based on the same data • Repeatability (in MSE): variation between successive measurements of the same part or characteristic, by the same person, using the same instrument; also known as test-retest error or operator uncertainty. • Reproducibility (in MSE): the difference in the average of measurements made by different persons measuring the same part or characteristic • Required Waste: process that adds no value to the product, but is required by the current process

Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 5

Lean Six Sigma

• Rework: any work that must be done to correct product or process defects • Risk Priority Number (RPN): used in an FMEA to assess relative priority of potential solutions; calculated as “Severity x Occurrence x Detectability” • Root Cause: the source of a problem which, if eliminated, would prevent recurrence of the issue • RPN: see Risk Priority Number • RTY: Rolled Throughput Yield; the probability that a part will make it through multiple process steps without a defect • Sample: set of elements drawn from and analyzed to estimate the characteristics of a population • SCOR: Supply Chain Operations Reference; a methodology that extends the scope of the value stream, starting with your supplier’s supplier and continuing to your customer’s customer • Setup Time: the elapsed time from production of the last good product to the production of the first good product; associated with changing the process from one product to another • Severity (in FMEA): an assessment of how serious the effect of the potential failure mode is on the customer; the customer in this case could be the next operation, subsequent operations, or the end user • Sigma (Excel function): account for shift and drift if necessary by adding 1.5; or see Reference Chart in the appendix • Sigma: 18th letter of the greek alphabet; mathematically understood to represent standard deviation • Significant Characteristics (in FMEA): those items which require SPC and quality planning to ensure acceptable levels of capability • SIPOC: boundary-scoping tool used in the design phase to identify Suppliers, Inputs, Process, Outputs, and Customers • Six Sigma: philosophy focuses on defect prevention through the use of statistical tools as opposed to defect detection through inspection • SMED: Single Minute Exchange of Dies; SMED performance levels for the changing of tooling (9 minutes and 59 seconds or less) • SOP: Standard Operating Procedure • SPC: Statistical Process Control

Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 6

Lean Six Sigma

• Special Cause: variation that is a result of a special circumstance; on a control chart, by definition, special causes always fall outside control limits • Standard Deviation: parameter used to characterize the “process dispersion” • Standard Operating Procedures: procedures that describe how the process is run and identify certain factors to monitor and maintain; standard procedure for running the process • Stretch Goals: goals and objectives that require employees to achieve more than normally thought possible • Subgrouping: a method of organizing (classify, stratify, group, etc.) data from a process to ensure the greatest similarity among the data in each subgroup and the greatest difference among the data in different subgroups. Groups need to be selected rationally, i.e. you have a belief that the groups are different and important. • Takt Time: “takt” is German for the word metronome; synchronizes the pace of the process to match the pace of customer demand; calculated as available time divided by customer demand • TDU: total defects per unit, the sum of all the DPUs for all parts in an assembly or all process steps in a process flow diagram • Thought Process Map (TMAP): project strategy-planning tool • Throughput Time: Cycle Time + Queue Time; actual time for a product to move through a production process • Upper Control Limit (UCL) / Lower Control Limit (LCL): control limits that are calculated from timeseries process data; they are also referred to as the voice of the process • Upper Spec Limit (USL)/Lower Spec Limit (LSL): customer supplied specification limits or tolerance for a process output; they are also referred to as the voice of the customer. • Value Stream Map (VSM): a map of the product, information, and material flows of a process; with valueadded and non-value added data gathered and displayed for each step • Value: a capability provided to a customer at the right time at an appropriate price, as defined in each case by the voice of the customer • Value-added: transforms the form, fit and or function of a product or service as defined by the customer the first time Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma Glossary – Page 7

Lean Six Sigma

• Visual Control: indicators which allow employees to detect visually whether a process is in or out of control; examples include temperature gauges, control charts, tool boards, etc. • Voice of Customer (VOC): customer requirements/specifications of the process (see Upper Spec Limit) • Voice of Process (VOP): natural variability of a process typically characterized by a normal distribution (see Upper Control Limits) • VSM: see Value Stream Map • Waste: anything that adds cost without producing a corresponding benefit • X: the inputs to a process (inputs for individual process steps/tasks are identified using the lower-case “x”) • X-Bar Chart: an averages chart, also called the “between” chart because the points represent variation between groups; this control chart examines the average of samples in a subgroup • Y = f(x): Function used to describe a process whereby x’s represent all the inputs to a process (factors) and Y represents the output of the process (response) • Y: the output of a process (outputs of individual process steps/tasks are identified using the lower-case “y”)

Copyright 2005, AIT Group Inc. All rights reserved.

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Lean Six Sigma

Author

Steven Bonacorsi is a Senior Master Black Belt instructor and coach. He has trained hundreds of Master Black Belts, Black Belts, Green Belts, and Project Sponsors and Executive Leaders in Lean Six Sigma DMAIC and Design for Lean Six Sigma process improvement methodologies. Steven is a board member for the Boston Chapter of the Industry of Industrial Engineers. Full Bio: http://www.linkedin.com/in/stevenbonacorsi Lean Six Sigma White Belt Certification: • Add Lean Six Sigma White Belt (Basic Awareness) Training and Certification to your Resume or Job Skills. • Learn topics from one of the original Master Black Belts and world experts on Value Stream Mapping, 5s, Process Capability, Deployment Planning, Roles and Responsibilities, FMEA Risk Analysis, Control Plans and more. • Certificates will be signed for all who complete the 2 hour training session.

Copyright 2005, AIT Group Inc. All rights reserved.

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Learn More about The AIT Group http://www.theaitgroup.com

Copyright 2005, AIT Group Inc. All rights reserved.

Lean Six Sigma

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Lean Six Sigma

Who is AIT? • AIT is a premier provider of Lean, Six Sigma and Supply Chain solutions. • Solutions are customized to the customer – not one size fits all. • The company was started in 1998 by three individual that recognized extremely early in the industry how well Lean, Six Sigma and Supply Chain disciplines integrate. • Our goal is the complete transfer of knowledge via client specific solutions – not training. • Your instructors from AIT are Certified Master Black Belts and Lean Experts. • We have worked with many different clients and some of the largest companies in the world. • We have Offices in the US, Europe, Mexico and China.

The AIT Group is an international consulting firm that has been specifically designed to help companies increase profitability by improving overall business performance and customer satisfaction through the integrated application of:

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Six Sigma www.theAITgroup.com

The AIT Group excels in implementation … not recommendation! Copyright 2005, AIT Group Inc. All rights reserved.

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