1、2022年8月16日星期二精益生产之普通拉系统精益生产之普通拉系统GenericPullSystem(中中英文对照英文对照)MeasureAnalyzeControlImproveLean Six Sigma普通拉系统u定义普通拉系统的最佳实践u 案例举例u如何去决定普通拉水准u练习u天线模拟RD010402Lean Six Sigma Improvement Process Road MapAnalyzeControlImproveDefineIdentify ProblemDevelop List of CustomersDevelop List of CTQs from Voice of
2、 the CustomerFinalize Project Focus and Key MetricsComplete PDFMeasureMap Business ProcessMap Value StreamDevelop DataCollection PlanConduct MeasurementSystem AnalysisCollect DataConduct Process Capability AnalysisAnalyzePropose Critical XsPrioritize Critical XsVerify Critical XsEstimate the Impact
3、of Each X on YQuantify the OpportunityPrioritize Root CausesConduct Root Cause Analysis on Critical XsImproveCritical Xs ConfirmedDevelop Potential SolutionsSelect SolutionOptimize SolutionPilot SolutionControlImplement Process Changes and Controls Write Control PlanCalculate Final Financial/Process
4、 MetricsTransition Project to Future OwnersIdentify Project Translation OpportunitiesMeasureDefineProject ID ToolsProject Definition FormNet Present Value Analysis Internal Rate of Return Analysis Discounted Cash Flow Analysis PIP Management ProcessRACIQuad ChartsProcess MappingValue AnalysisBrainst
5、ormingMulti-Voting TechniquesPareto ChartsC&E/Fishbone DiagramsFMEACheck SheetsRun ChartsControl ChartsGage R&RCp&CpkSupplyChainAccelerator AnalysisMulti-VariBox PlotsInteraction PlotsRegressionANOVAC&E MatricesFMEABrainstormingPull SystemsSetup ReductionTPMProcess FlowBenchmarkingAffinityDOE Hypoth
6、esis TestingForce FieldTree DiagramsGantt ChartsCheck SheetsRun ChartsHistogramsScatter DiagramsControl ChartsPareto ChartsInteractive ReviewsPoka-YokeRevised 1-12-02Learning ObjectivesuUnderstand the best practice definitionuHow to apply this best practice in various environmentsuAble to determine
7、the levels of inventory using the five stepsuDemonstrate this best practice through exercises and simulation课程目的u理解最佳实践的定义u如何在多变的环境中应用这个最佳实践u能够去决定库存的水平用5个步骤u通过练习和模拟来示范这一最佳实践Whats in It for Me?uUnderstand the reason for this tool in different environmentsuHow to use this tool for potential black belt
8、 projects我学到了什么?u理解在不同环境中使用这个工具的原因u对于黑带潜在项目如何去使用这个工具Generic Pull SystemsuGeneric Pull Systems limit the amount of Work-In-Process inventory in order to control cycle time.普通拉系统u普通拉系统为了控制周转时间限制了制程库存的数量（Work-In-Process）.WIP CapExitsStartsTriggerGeneric Pull System DefinedDefinition:uA Generic Pull Sys
9、tem establishes a WIP cap on the amount of inventory within a predefined physical work area(set of workstations)or process.uTo maintain the WIP cap,exits from the process trigger starts into the process.Establishing WIP cap is the key to cycle time reduction!WIP CapExitsStartsTrigger普通拉系统的定义定义定义:u一个
10、普通拉系统是在一个预先确定的物理工作区域（工作站）或流程中，在存货金额上建立了一个WIP cap.u来维护 WIP cap,从流程中的“出口”（exits）来触发进入流程的“出发”（Starts).建立WIP cap 是降低周转时间的关键When to Use Generic PulluAlwaysuGeneric Pull systems can be used in any of the following manufacturing/transactional environments:nRepetitive process/repetitive productlSimilar prod
11、ucts/parts run within same process flowuExample:Automotive assembly line,customer order processingnRepetitive process/non-repetitive productlDissimilar products/parts run within same process flowuExample:Build to order printed circuit board manufacturer,customer complaint processingnNon-repetitive p
12、rocess/non-repetitive productlDissimilar products/parts run within a dissimilar process flowuExample:Machine model/prototype shop,NPI processesuGeneric Pull systems should always be used when a replenishment pull system is implemented 何时使用普通拉系统u永远u普通拉系统可以被使用在下列任何制造/事务处理的环境中:n重复的流程/重复的产品l类似的产品/零件在同一个
13、流程中运行u例如:汽车的组装线,客户定单流程n重复的流程/不重复的产品l不同的产品/零件在同一个流程中运行u例如:根据定单定制的电路板制造商,客户投诉流程n不重复的流程/不重复的产品l不重复的产品/零件在不同的流程里运行u例如:机器模型/原型制作车间,NPI流程u当补充拉系统被实施时，普通拉系统将永远被使用When flying from DFW to OHare,we often wind up waiting on the ground due to“flow control.”Since OHare is overloaded,air traffic control keeps us i
14、n Dallas until the congestion over OHare clears,versus getting there and circling Chicago.Either way,we end up late.However,using the“flow control”(fixed WIP)method,we use less fuel and reduce the risk of an accident.In addition,we keep our options open(such as re-routing if the weather becomes too
15、bad).In a pull system,maintaining a“fixed WIP”keeps work orders in paper form as long as possible.This provides the greatest flexibility to schedule/engineering changes.In addition,low WIP means a faster cycle time,which increases the probability releases are based on actual customer orders versus f
16、orecast.“Fixed WIP”Improves Flexibility当航班从 DFW 到 OHare,我们通常由于“流控制”而在地面上紧张的等待。因为OHare机场超负荷了,空中交通控制要求我们在达拉斯等待，直到OHare 的堵塞清除掉；与在芝加哥上空盘旋相比，任何一条路都注定会让我们晚点。可是，使用“流控制”(固定WIP)方式,我们用的燃油更少且降低了事故的风险.此外,我们仍然享有我们的选择权(例如重新选择路线如果天气变的更糟的话).在一个拉系统中，维护一个“固定WIP”可以使工作指令尽可能的在计划阶段。这样为制定计划/工艺变更提供了最大的弹性。此外，底WIP意味着更快的周转时间，
17、这样可以增加基于客户的订单而不是根据预测“固定的WIP”改善弹性The Power of a WIP CapWIP Cap Cycle time is reduced and stableNo WIP Cap Cycle time fluctuates with amount of WIPWIP Cap的能力WIP Cap 周转时间被降低了且稳定没有WIP Cap 周转时间随WIP的金额而波动United Technologies:Hose and Fittings Division(PTG)BeforeMetal ware flare running large batches with l
18、arge amounts of WIP联合技术:Hose and Fittings 分部(PTG)之前之前金属器械运行大批次并伴随大的WIPUnited Technologies:Hose and Fittings Division(PTG)AfterMetal ware flare area with controls placed on material releases to the department联合技术:Hose and Fittings 分部(PTG)之后之后金属器械区域对发料到部门的材料放置进行控制Teledyne Continental MotorsBeforeNo in
19、ternal limits existed for the number of cylinders a supplier could push to its customer,resulting in large amounts of WIP in the line.Teledyne Continental Motors之前之前对于缸体数量没有内部限制，供应商向客户推动供应，导致生产线有大量WIP.Teledyne Continental MotorsAfterLimits were established workstations and the line was drained of ex
20、cess WIPTeledyne Continental Motors之后之后建立限制数量，过多的WIP从工位和生产线清除How to Size a Generic Pull System1.Determine current Manufacturing Cycle Time(MCT)2.Determine current Manufacturing Cycle Efficiency(MCE)3.Identify appropriate target MCE 4.Calculate theoretical best MCT5.Calculate WIP cap如何确定普通拉系统的规模1.确定目
21、前的制造周期时间(MCT)2.确定目前的制造周转效率(MCE)3.识别适合的MCE目标4.计算理论上的最佳MCT5.计算 WIP capManufacturing Cycle TimeuMCT The time from work order release into manufacturing until completion/movement into shipping/finished goods.uIt is measured as:uWIP is the inventory level at a given point in timeuEXITS is the amount of w
22、ork completed over a given period of time(Weekly,Daily)EXITSWIPMCT 制造周期时间uMCT 从工作单的下发到制造，直到完成/移动到成品的时间.u他被量测如:uWIP 是在给定时间点的存货水平uEXITS 是在一个给定的时间内(每周，每天)工作完成的金额EXITSWIPMCT MCTExits=20 units/day WIP=Sum of all Inventory within Physical work area=100 unitsMCT=100 units/20 units per dayMCT=5 daysExample:
23、Calculating MCTEXITSWIPMCT MCTExits=20 单位/天 WIP=在物理工作区域里所有存货的总和=100 单位MCT=100 单位/20 单位每天MCT=5 天举例:计算MCTEXITSWIPMCT Manufacturing Cycle EfficiencyuMCE is a measure of the relative efficiency in a production system.It represents the percentage of value add time(changing form,fit,function)of a product
24、down the critical path.uIt is measured as:uMCE is the performance indicator for Generic Pull Systems.x100PCTTime AddValueMCEPath Critical制造周转效率uMCE 是在生产系统中相关联的效率量测.它代表关键路径中的增值时间（改变形状，尺寸，功能）的比率.uMCE 是对于普通拉系统的绩效指示器.x100PCTTime AddValueMCEPath CriticalExample:Calculating MCE.2 hrs.3 hrs.2 hrs.2 hrs.6 h
25、rs1hrsBake7.0 hrs.5 hrsReworkInspect*Critical Path=Value AddTotal=10.0 hours Value AddCritical Path=8.5 hours*MCT=5.0 days MCE=(8.5-7)/(5 x 8)-7)*=1.5/33 =4.5%FinishedGoodsRawMaterial*Time at the Inspect workstation does not contribute to the Critical Path calculations because inspection is not valu
26、e add.*Bake/Machine times are not included in MCE calculations举例:计算 MCE.2 hrs.3 hrs.2 hrs.2 hrs.6 hrs1hrsBake7.0 hrs.5 hrsReworkInspect*Critical Path=Value AddTotal=10.0 hours Value AddCritical Path=8.5 hours*MCT=5.0 days MCE=(8.5-7)/(5 x 8)-7)*=1.5/33 =4.5%FinishedGoodsRawMaterial*在检验工作站中的时间没有算到关键路
27、径的计算中，因为检验不是增值的.*烘烤/机器时间没有包含在MCE的计算中Target MCEuTable of Manufacturing Cycle Efficiency Benchmarks based on process applicationApplication Low End MCE High End MCE Machining 1%25%Fabrication 10%30%Assembly(with Batch Transfer)15%40%Assembly(without Batch Transfer)20%50%目标 MCEu制造周转效率表是基于流程应用的基准应用应用 低端
28、低端MCE 高端高端MCE 加工 1%25%装配 10%30%组装(用批传输)15%40%组装 20%50%(不用批传输)Theoretical Best MCTTheoretical Best MCT is:uThe“best”or lowest manufacturing cycle time achievable based on the process characteristics.uIt is measured as:uVA(Critical Path)is the value add time along the critical path.It does not include
29、 the value add time of parallel processes.MCETarget VAMCTpath)(criticalTB理论的最佳MCT理论的最佳 MCT 是:u基于过程特性可以达到的“最佳”或最低的制造周期时间.u它可以由下列公式计算:uVA(Critical Path)是沿关键路径的增值时间，它并不包括并行工序的增值时间MCETarget VAMCTpath)(criticalTBMCTTB=1.5 hrs/.2 =7.5 hrs =1 dayExample:Theoretical Best MCTMCETarget VAMCTpath)(criticalTBMC
30、TTB=1.5 hrs/.2 =7.5 hrs =1 day举例:理论的最佳MCTMCETarget VAMCTpath)(criticalTBWIP CapuThe WIP cap determines the maximum WIP allowed within the process at any time.uIt is measured as:RateExit MCTCap WIPTBWIP CapuWIP cap 决定在任意时间内过程允许的最大WIP.u它可以由下列公式计算:RateExit MCTCap WIPTBWIP Cap=1 day x 20 units/day=20 un
31、its Example:WIP CapRateExit MCTCap WIPTBWIP Cap=1 day x 20 units/day=20 units 举例:WIP CapRateExit MCTCap WIPTBExample:SummaryCurrent State:Desired State:MCT=5 daysWIP=100 unitsExits=20 units/dayValue Add time=1.5 hrsMCE=4.5%MCT=1 dayWIP=20 unitsExits=20 units/day Value Add time=1.5 hrsMCE=20%举例:摘要目前的
32、状况:期望的状况:MCT=5 daysWIP=100 unitsExits=20 units/day增值时间增值时间=1.5 hrsMCE=4.5%MCT=1 dayWIP=20 unitsExits=20 units/day 增值时间增值时间=1.5 hrsMCE=20%TimeValue AddExitsWIPPCTPCECurrentMonth 01.5 hrs20/day10054.5%Step 1Month 11.5 hrs20/day8046.0%Step 2Month 21.5 hrs20/day6038.8%Step 3Month 31.5 hrs20/day40216.7%S
33、tep 4Month 41.5 hrs20/day20120.0%WIP Reduction Plan ExampleAchieving WIP Cap uTypically the current WIP level will be significantly greater than the WIP Cap level.Therefore,a plan must be developed to reduce the WIP.时间时间增值增值 ExitsWIPPCTPCECurrentMonth 01.5 hrs20/day10054.5%步骤1Month 11.5 hrs20/day804
34、6.0%步骤2Month 21.5 hrs20/day6038.8%步骤3Month 31.5 hrs20/day40216.7%步骤4Month 41.5 hrs20/day20120.0%WIP 降低计划降低计划达到 WIP Cap u目前的WIP水平明显高于WIP Cap 的水平.因此，必须制定计划减少WIP.How to Release WIP into a Generic Pull SystemuRelease logic for Generic Pull SystemsActual WIP=WIP CapDo not release any more work into this
35、process flow.Actual WIP 0).The amount of work released should make Actual WIP approximately equal to WIP cap.如何将WIP发放到普通拉系统中u普通拉系统的发放逻辑实际WIP=WIP Cap不发放任何的工单到流程中.实际WIP 0).发放的工单将让实际的WIP和WIP cap大致相等。Generic Pull Exercise:Part AuGiven the following Information:nAverage Demand is 10 units/daynCurrent MCT
36、 is 20 daysnValue Add Time=8 hoursnFabrication Shopn1 shift operation that works 5 days per weekuAnswer the following questions:nWhat should my WIP cap(in units)be?nHow much inventory should I drain from the operation?普通拉系统的练习:零件 Au已知下列信息:n平均的需求是 10 单位/天n目前的MCT 是 20 天n增值时间=8 小时n装配车间n每周工作5天，一班运作u回答下列
37、问题:n我的 WIP cap(单位)将会是什么?n应该从工序中减少多少库存？Generic Pull Exercise:Part BuUsing the calculated WIP cap from Part A answer the following questions:nCurrent WIP level is 105 units and my MRP system wants me to release a quantity of 5 units into the line what should I do?Why?nCurrent WIP level is 95 units and
38、 my MRP system wants me to release a quantity of 5 units into the line what should I do?Why?nCurrent WIP level is 98 units and my MRP system wants me to release a quantity of 5 units into the line what should I do?Why?普通拉系统的练习:零件 Bu用零件A部分的WIP Cap计算结果回答下列问题:n目前的WIP水平是105 单位，我的MRP系统要求我发放一个数量为50单位的工单到生
39、产线上，我应该做什么？为什么？n目前的WIP水平是95 单位，我的MRP系统要求我发放一个数量为5单位的工单到生产线上，我应该做什么？为什么？n目前的WIP水平是98 单位，我的MRP系统要求我发放一个数量为5单位的工单到生产线上，我应该做什么？为什么？How to Determine Unit of Measure for WIP ControluConceptually all Generic Pull Systems are identical,the primary difference being the WIP control parameter.The WIP control p
40、arameter is the unit of measure for WIP used to control the pipeline.uThree types of parameters are used:nQuantitynEquivalent UnitsnTimeuThe most effective method for determining the proper parameter is using the“Coefficient of Variation(CV)”for the product value add times.如何决定WIP控制的量测单位u概念性的普通拉系统都是
41、同样的，主要的不同点在于WIP的控制参数.WIP的控制参数是指用来控制整个路径的WIP的度量参数.u三种类型的指标被使用:n数量n等价单位n时间u确定适合参数的最有效的方法是将“变量系数”用于产品增值时间。Coefficient of Variation(CV)uThe CV of the Value Add Times is used to determine how the workload in a process is affected by changes in product mix.uIt is measured as:u“CV is a reasonable relative
42、measure of the variability in a process.”Factory Physics,Hopp&SpearmanMeanStdDevCV 变量系数(CV)u增值时间的CV用来确定过程中的工作量是如何受混型产品变化影响的，按下式计算：u“CV是过程变异性相对合理的量测方法.”Factory Physics,Hopp&SpearmanMeanStdDevCV Example 2:Calculating CVStd.Dev.(s)=Coeff.Var.(CV)=Mean(x)=Formulas:Part NumberTotal Process Value Add Time
43、a1b1.5c1.5d3e2f1g1h1.5I2.5TOTAL15n=9Mean=1.67Std Dev=0.71CV=0.42nVAia)()1()(22nnxxnxs举例 2:计算 CVStd.Dev.(s)=Coeff.Var.(CV)=Mean(x)=公式:零件零件全过程的增值时间全过程的增值时间a1b1.5c1.5d3e2f1g1h1.5I2.5TOTAL15n=9Mean=1.67Std Dev=0.71CV=0.42nVAia)()1()(22nnxxnxsSelecting WIP Control ParameterTotal Process Value Add TimeWIP
44、 Control ParameterLow Variability:CV=0.75Quantity(Pieces)Medium Variability:0.75 CV 1.33Time选择WIP控制参数全过程增值时间全过程增值时间WIP 控制参数控制参数低变异:CV=0.75数量(件数)中变异:0.75 CV 1.33时间Example 3:Identifying WIP Control ParameterReference Handouts for analytical detailLow VariabilityMedium VariabilityHigh VariabilityMean(x
45、):1.673.704.56StdDev(s):0.713.916.59CV(s/x):0.421.061.44Parameter:QuantityEquiv.Units/TimeTimeResizing Frequency:QuarterlyMonthlyWeekly举例 3:确定 WIP 控制参数详细分析参考分发的资料低变异中等变异高变异Mean(x):1.673.704.56StdDev(s):0.713.916.59CV(s/x):0.421.061.44参数:数量等价单位/时间时间调整规模大小的频次:每季度每月每周Example 4:Calculating Equivalent Un
46、itsHighest volume product represents equivalent unitProductVA Time(Hrs/Piece)Demand(Pieces/Week)Equivalent Unitsa565/10=0.5b1010=Equivalent10/10=1.0c20220/10=2.0d40440/10=4.0n=4x=18.75s=15.48CV=0.83举例4:计算等价单位最高产量的产品代表等价单位产品产品增值时间增值时间(小时小时/件件)需求需求(件件/周周)等价单位等价单位a565/10=0.5b1010=等价数10/10=1.0c20220/10=
47、2.0d40440/10=4.0n=4x=18.75s=15.48CV=0.83Performance Measurements of a Generic Pull SystemuPull System effectiveness measurementsnMCT and MCT VariancenMCEnActual vs.Target WIPuAdditional measurementsnWIP TurnsnBacklog by Order,Part and AgenOn-Time DeliverynQuantity of Daily CompletionsuRefer to Dashb
48、oard best practice for specifics普通拉系统的绩效评估u拉系统的效力量测nMCT 和MCT的变化量nMCEn实际的WIP vs.目标的 WIPu其他的量测nWIP 周转次数n按订单、零件及期限分类订货n准时交货n日完成数量u详细信息查阅最佳实践的宣传板TakeawaysuUnderstand the importance of Generic PulluAble to size(calculate)a Generic Pull SystemuHow to apply this best practice总结u理解普通拉系统的重要性u能够去计算一个普通拉系统的规模u
49、如何去应用这一最佳实践MeasureAnalyzeControlImproveLean Six SigmaAntenna ExerciseuRun Exercises 1-4uRecord Results and ObservationsuDiscuss Exercises 1-4MeasureAnalyzeControlImproveLean Six Sigma天线练习u练习 1-4u记录结果和观察信息u讨论练习 1-4Learning ObjectivesuDemonstrate the fundamental relationship between WIP,Cycle Time,and
50、 ThroughputuDemonstrate the WIP impact on a processuDemonstrate the bottleneck impact on a processuRecord each simulation result/observation and discuss in detail课程目的u示范WIP、周转时间和生产能力的基本关系原理u示范在流程中WIP的影响u示范在流程中的瓶颈影响u记录每个模拟的结果/观察和讨论细节Whats in It for Me?uVisually see the impact of barriers(WIP and Bott
