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Lean Manufacturing (PP)

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Kaizen Blitz: A multi-level team of 5-10 people that work 10-14 hours a day to rapidly develop, test and refine solutions to problems and leave a new solution in place in only a few days. They don’t plan, they don’t propose, they do. ▪ A Kaizen Blitz, used in conjunction with the Toyota Production System (TPS) and current Lean Manufacturing principles, can serve as a catalyst for the initial implementation of a plant wide Lean Manufacturing initiative. Kanban Concept: o Meaning- Sign, Index sign o It is the most important Japanese concept opted by Toyota. o Kanban System combined with unique scheduling tools, dramatically reduces inventory levels. o Enhances supplier/customer relationships and improves the accuracy of manufacturing schedules. o A signal is sent to produce and deliver a new shipment when material consumed. o These signals are tracked through the refill cycle and bring extraordinary visibility to suppliers and buyers. Critical Ingredients of Lean are: o Specify Value, Identify Value Steam and Eliminate waste, make value flow, Let the customer pull value through the process, and purse perfection (VVFPP) 7 elements of manufacturing wasters: o Waiting, overproduction, transportation, defects, inventory, motion, and processing (WOTDIMP) Fundamental Concept: Make what is needed, when it is needed, in the amount needed 5S: Sort, Straighten, Shine, Standardize, and Sustain

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Takt Time:

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Ask why 5 times for root cause

Chapter 1,2 & 3 (PP) •

Six Sigma: a process that enables companies to increase profits dramatically by streamlining operations, improving quality, and eliminating defects or mistakes in everything a company does, form raw materials to finish goods. 6 sigma process generates a defect probability of 3.4 parts per million (PPM). (most companies go for 4σ)

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For any process, variation is the main reason for performance and the key focus of six sigma It costs about 5 times more to attract a new customer as it does to keep an old one. Roles of Six Sigma belts: o Black belt: full time change agent and improvement leader. o Green Belt: works on projects part time, either as team member for complex projects or as a project leader for simpler projects o Champion: very active sponsorship and leadership role in conducting and implementing six sigma projects o Master Black belt: leadership role as keeper of six sigma process and advisor to executives or business unit managers. o Senior Executive: Provides the impetus, direction & alignment necessary for Six Sigma ultimate success. o Executive Committee member: Top management of an organization Feedback Loops: A feedback loop relates information about outputs from any stage to another stage to make an analysis of the process. Defects per Opportunity (DPO): number of defects divided by number of defect opportunities (ex. 20 errors in 100 services = DPU of 0.20) Defects per Unit (DPU): The average of all defects for a given number of units Defects per Million opportunities (DPMO): a quality metric often used in six sigma process that calculates by the number of defects observed divided by the number of opportunities defects compared to 1 million units. Yield: the proportion of units within specification divided by the total number of units Rolled Throughput Yield (RTY): the product of the yields from each step in a process. RTY = Y1%*Y2%*Y3%

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Define

Measure

Analyze

Improve

Control

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Dashboard: a tool used by management to clarify and assign accountability for the “critical few” key objectives, key indicators, and project tasks needed to steer an organization toward its mission statement. o Strategic Benefits: Monitor deployment of mission statement, balance management’s attention between customer, process, employee and financial key objectives. Also, it increases communication between and within the levels of an organization. o Tactical Benefits: Linking all processes to the mission statement, eliminating overreaction to random noise in organizational processes and develop and test hypotheses about effectiveness of potential process improvement. Four Basic Categories of dashboard key objectives: Financial key objectives, process improvement key objectives, Innovation/customer satisfaction Key objects, and employee growth and development key objectives. Mission statement: A declaration of the reason for the existence of an organization Key objectives: 2 kinds o Business Objectives: goals that must routinely be pursued within an organization if it is to function. (ex: answering inquires in call center, preparing paycheck in payroll, etc.) o Strategic Objectives: goals that must be accomplished o purse the presidential strategy of organization (ex:

Chapter 1 Book • • • •

VOC (voice of the customer): specification limits (LSL and USL) VOP (voice of the process): the distribution of measurements of the outputs from a process over time Six sigma promotes that the distribution of output for a stable normally distributed process (VOP) should be designed to take up no more than half of the tolerance allowed by the specification limits (VOC) Taguchi Loss function: expresses the loss of deviating from nominal within specifications o 𝐿(𝑦) = 𝑘(𝑦 − 𝑚)2 , y = value of quality characteristic for a particular item of product/service, m = nominal value for quality characteristic, k =a constant, A/(d2). A = loss (cost) of exceeding specification limits (ex: the cost to scrap a unit of output), d = allowable tolerance from the nominal value that is used to determine specification limits.

Chapter 2 Book •

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SDSA (Standardize-Do-Study-Act) model: a method/roadmap that helps employees standardize a process o Standardize: Employees study the process and develop “best practice” methods with key indicators of process performance. o Do: Employees conduct planned experiments using the best practice methods on a trial basis. o Study: Employees collect and analyze data on the key indicators to determine the effectiveness of the best practice methods. o Act: Mangers establish standardized best practice methods and formalize them through training. PDSA (Plan, do, study, act)

Chapter 3 Book •

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Key Indicators: measurement that monitors the status of a key objective. There are 5 types: o Attribute: Used when a key objective is being monitored using attribute data over time. (Ex: % of customers complaining per month) o Measurement: Used when a key objective is being monitored using measurement type data. (Ex: cycle time) o Binary: used to monitor whether an action has been accomplished by a given date. (Ex: Computer system operation by July 12, 2004? Yes or No). o List Key: used to monitor a group of people or items for compliance to some deadline or standard. (Ex: List of employees not trained in the new safety standard by December 31, 2004) o Gantt Chart: used as record-keeping device for following the progression in time of the task required to complete a project Flag Diagram: a tool used to track the contributions of subordinate key indicators to the pursuit of superior key indicators. There are 2 types: Additive and nonadditive.

Chapter 4 (Define) • • •

Define Phase 3 distinct parts: Prepare initial project charter, conduct SIOPC analysis, perform VOC analysis. Team Charter: An agreement between management and team about what is expected Project Charter: A form that has key information about the project. o Define project o What is critical to quality (CTQ) to the customer o Business case ▪ What is the name of the process? ▪ What is the aim of the process? ▪ Why do the project at all? ▪ Why do the project now? ▪ What are the consequences of not doing the project? ▪ What presidential objectives on the dashboard are supported by the project? o Problem and goal statement ▪ Problem: describes the problem, opportunity, or objective in clear measurable terms ▪ Goal: Describes the team’s improvement objective. Begins with a verb like reduce or eliminate o Scope of a project: Problem/opportunity, establish goals, identify criteria, communicate

• Process: Process in which opportunity exists • Project Description: Project’s purpose and scope • Project Scope: Define the part of the process that will be investigated and is created by the following questions: o

What are the process boundaries?

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What, if anything, is out of bounds?

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What resources are available for the project?

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Who can approve expenditures?

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How much can the team spend beyond its budget without authority?

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What are the obstacles and constraints of the project?

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What time commitment is expected of team members?

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What will happen to each team member’s regular job during the project?

• Project objective: Define the baseline, goal & target. Should address the problem statement, quantify performance improvement, identify timing, measurable. Contains five key elements:

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Process, critical-to-quality(CTQ) characteristics measure, CTQ target, CTQ direction, and deadline

• Business Case: Define the improvement in business performance anticipated and when • Team Members: Who are the full-time team members • Expected Customer Benefits: Who is the final customer? What benefit will they see and what are their most critical requirements? • Problem statement: Should focus the team on a process deficiency and communicate significance to others. o

What is wrong, Where it happened, When it occurred, To what extent, and I know because...

• Primary Metrics: used to measure success and consistent with problem statement objectives (usually reported as a time series). Ex: rolled throughput yield versus FTY, Defects per unit versus proportion defective • Secondary Metrics: tracks potential negative consequences • SIPOC: A simple tool for identifying the suppliers and their inputs into a process, the high-level steps of a process, the outputs of the process, and the customer segments interested in the outputs that Define process boundaries, identify data collection opportunities, clarify who are true customers of the process

• SMART: (Specific, measurable, attainable, relevant, time bound) • Proactive VOC systems: Interviews, surveys, benchmarking, comment cards, quality scorecards, sales visits. Data collected before customer experiences their first encounter with product, unlike reactive. • VOC analysis o

Step 1: Select product/service, or process in a given market to serve as subject of 6σ project

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Step 2: Identify lead users and heavy users: ▪

Lead users: consumers of a product/service who are months or years ahead of regular users

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Heavy users: consumers who purchase relatively large quantities of a product

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Step 3: Collect proactive data from lead and heavy users about emotions and circumstances surrounding their use of the product, service, or process under study, which is called circumstantial data.

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Step 4: Classify the VOC data a circumstantial data or product-related data. ▪

Product related data: Identifies the current expectation and perception soft lead and heavy users

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Step 5: Team members survey regular users to identify the critical circumstantial data for the product/service

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Step 6: Team members determine focus point for each key circumstantial data point or group of key circumstantial data points using the affinity diagram ▪

Affinity diagram: a tool used to identify the critical themes called focus points underlying circumstantial data points.

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Focus point: underlying themes for one or more circumstantial data points

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Step 7: Create potential improvements and innovations by translating focus points into detailed, unambiguous, qualitative statements of needs and wants in the language of design engineers, which are called Cognitive images.

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Step 8: Develop a questionnaire that can be used by team members to classify cognitive images into strategic categories. ▪

Kano questionnaire: a tool used by team members to classify a set of cognitive images into a kano quality category •

One way (O): user satisfaction is proportional to the performance of the feature. The less performance, the less user satisfaction, and the more performance, the more user satisfaction

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Must-Be(M): User satisfaction is not proportional to the performance of the feature. The less performance, the less user satisfaction, but high performance creates feelings of indifference to the feature.

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Attractive (A): User satisfaction is not proportional to the performance of the feature. Low levels of performance create feelings of indifference to the feature, but high levels of performance create feelings of delight to the feature.

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Indifferent (I): User does not care about the feature

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Questionable (Q): User’s response does not make sense (delighted whether feature is present or absent)

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Reverse: User offers responses opposite the responses expected by individuals conducting the Kano survey (delight if feature is absent and vice versa)

• American National Standards Institute (ANSI): approved a standard set of flowchart symbol: • Market Segmentation: the dividing of a market into homogeneous subsets of customers, where any subset may conceivably be selected as target market to be reached with a distinct marketing mix • Affinity diagram: a tool used to identify the critical themes called focus points underlying circumstantial data points. • QPT (Quality Project Tracking) • Tollgate reviews: A 6σ team presents its project to their champion and the process owner for the approval in a series of tollgate reviews. • 5W1H (5 whys and 1 how) Chapter 5 (Measure) •

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Measure Phase: concretely understanding the operational definition, measurement system, and current capability of each critic-to-quality(CTQ) characteristic. o 1st task: Develop an operation definition for each CTQ identified in the define phase o 2nd task: Conduct gage R&R study for reach CTQ to determine the capability of the its measurement system o 3rd task: Collect passive baseline data for each CTQ to determine whether the CTQ is stable and normally distributed Operational definition: promotes understanding between people by putting communicable meaning into words that contains 3 parts: o Criteria: establish VOP language for each CTQ and VOC specs for each CTQ

Test: compare VOP data with VOC specs for each CTQ for a given unit of output Decision: make a determination whether a given unit of output meets VOC specs Ex: Mary lends Susan her coat for a vacation but requests that it be returned clean. Clean is the CTQ, which is subjective to different opinions of “clean”. So, it is stated that Susan will et the coat dry cleaned ▪ Criteria: The coat is dry cleaned and returned to Mary ▪ Test: Mary determines whether was dry cleaned ▪ Decision: If the coat was dry cleaned, Mary accepts, otherwise Mary does not accept Variable Data: Continuous measurements such as length, voltage, viscosity Repeatability (precision): Variation in measurements obtained with one gage when used several times by one appraiser. Due to machine Reproducibility: Variation in the average of the measurements made by different appraisers using the same measurement system. Due to operators Gage R&R: used to estimate the proportion of observed total variation due to unit-to-unit and R&R variation o Crossed: When you don’t need to do destructive testing, and use the same exact parts or very similar o Nested: When you cannot use the same part, or find anything similar, due to destructive testing. Part-to-Part Variation: is the variability created by the measurement of the multiple parts under identical conditions R&R indices o ≤ 10% acceptable measurement system o 10%-30% may be acceptable based on upon application, cost of measurement device, cost of repair o ≥ 30% Not acceptable. Measurement system needs improvement Number of Distinct Categories Index o 1 unacceptable. One part cannot be distinguished from another. o 2-4 Generally unacceptable o ≥ 5 recommended X-Bar chart: plotted points, which represent, for reach operator, the average measurement on each part. Ideally, should above/below the UCL and LCL to show “lack of control” because it represents entire range of possible parts. R Chart: plotted points, which represent, for reach operator, the difference between the largest and smallest measurements on each part. Any points go above UCL, then that operator is having problems measuring consistently, so ideally should stay within the UCL and LCL. By Part Chart: shows all the measurement taken in the study, arranged by part. Ideally multiple measurements for each part will vary as little possible. The averages will vary enough that differences between parts are clear. By Operator: shows all the measurement taken in the study, arranged by operator. Ideally will vary an equal amount and Part averages will vary as little as possible. Operator*Part Interaction: shows the average measurements taken by each operator on each part in the study, arranged by part. Ideally, lines (connecting average) will follow the same pattern and that averages will vary enough that difference between parts will be clear Components of Variation: represents the sources of variation. In a good measurement system, the largest component is part-to-part variation. o o •

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Number of distinct categories = 𝑆

𝑆𝑃𝑎𝑟𝑡 𝑀𝑒𝑎𝑠𝑢𝑟𝑖𝑛𝑔 𝑆𝑦𝑠𝑡𝑒𝑚

× √2 : estimates how many separate group of parts system can

distinguish o < 2: system cannot discriminate between parts o =2: Parts can be divided into high and low groups, as in attributes data. o ≥ 5: The system is acceptable and can distinguish between parts Cpk: incorporates information about both the process spread and the process mean, which is a measure of how the process is actually performing and how it is capable of doing in the future. Xσ/3 = cpk. Generally, want at least 1.33 cpk (4 σ) to satisfy most customers. If negative it means that a process will produce output that is outside of customer spec limits. Ex: a tight group of bullet shots landing on the bull’s eye means high Cpk Ppk: Tells us how it has performed in the past and you cannot use it to predict the future Cp: relates how the process is performing to how it should be performing. Cp does not consider the location of the process mean, which tells you what capability your process could achieve if centered. Ex: a tight group of bullet shots anywhere. Capability analysis: assesses the capability of an in-control process when the data are from the non-normal distribution. Consists of a capability histogram and a table of process capability statistics. Stability (or drift): a change in the accuracy (bias), repeatability (precision), or reproducibility of a measurement system when measuring the same part for a single characteristic over time. o Bias over time (accuracy): difference between the observed process average and a reference value over time Linearity: the difference (bias) between the part reference value and the part average over the different values of the domain of the gage. o Bias over domain (accuracy): difference between th...