精益生產之補充拉系統(tǒng)RelenishmenullSysems中英

Replenishment

PullSystemsManufacturingPullSystemsPurchasePullSystemsBufferLocationsPullSystemPlatformsManualvs.ElectronicPullSystems:HandlingSeasonalityPerformanceMeasuresAppendixRD010402補充拉系統(tǒng)制造拉系統(tǒng)采購拉系統(tǒng)緩沖場所拉系統(tǒng)平臺手動vs.電子拉系統(tǒng)：操作的季節(jié)性績效量測附錄RD010402LeanSixSigma

ImprovementProcessRoadMapAnalyzeControlImproveDefineIdentifyProblemDevelopListofCustomersDevelopListofCTQ’sfromVoiceoftheCustomerFinalizeProjectFocus

andKeyMetricsCompletePDFMeasureMapBusinessProcessMapValueStreamDevelopData

CollectionPlanConductMeasurement

SystemAnalysisCollectDataConductProcess

CapabilityAnalysisAnalyzeProposeCriticalX’sPrioritizeCriticalX’sVerifyCriticalX’sEstimatetheImpactofEachXonYQuantifytheOpportunityPrioritizeRootCausesConductRootCause

AnalysisonCriticalX’sImproveCriticalX’sConfirmedDevelopPotentialSolutionsSelectSolutionOptimizeSolutionPilotSolutionControlImplementProcess

ChangesandControlsWriteControlPlanCalculateFinalFinancial/ProcessMetricsTransitionProjecttoFutureOwnersIdentifyProjectTranslationOpportunitiesMeasureDefineProjectIDToolsProjectDefinitionFormNetPresentValueAnalysisInternalRateofReturnAnalysisDiscountedCashFlowAnalysisPIPManagementProcessRACIQuadChartsProcessMappingValueAnalysisBrainstormingMulti-VotingTechniquesParetoChartsC&E/FishboneDiagramsFMEACheckSheetsRunChartsControlChartsGageR&RCp&CpkSupplyChainAcceleratorAnalysisMulti-VariBoxPlotsInteractionPlotsRegressionANOVAC&EMatricesFMEABrainstormingPullSystemsSetupReductionTPMProcessFlowBenchmarkingAffinityDOEHypothesisTestingForceFieldTreeDiagramsGanttChartsCheckSheetsRunChartsHistogramsScatterDiagramsControlChartsParetoChartsInteractiveReviewsPoka-YokeRevised1-12-023LearningObjectivesIntroductiontoReplenishmentPullSystemsLearnthebenefitsandapplicationsKnowthedifferencebetweenaManufacturingPullSystemvs.aPurchasePullSystemUnderstandkeyPullparametersandcalculationsIntroductiontothePullPlatformsKnowthekeybufferlocationswithinaprocess4學習目的介紹補充拉系統(tǒng)學習補充拉系統(tǒng)的好處和應用了解制造拉系統(tǒng)和采購拉系統(tǒng)的區(qū)別理解拉系統(tǒng)的關鍵參數(shù)及計算方法介紹拉系統(tǒng)的平臺了解流程中關鍵緩沖點的位置5What’sinItforMe?UnderstandwhatReplenishmentPullisandmakeapplicationstoyourenvironmentGainunderstandingonthemanytypesofPullSystems6我學到了什么?了解補充拉系統(tǒng)并并應用于您的工作環(huán)境中對各種類型的拉系統(tǒng)增進了解7

IntroductionReplenishmentPullSystemsestablishesstrategicallylocatedbuffersofpartswithinaprocess.RawmaterialManufacturedpartsPurchasedpartsFinishedgoodsDe-couplesthesupplyingprocessfromtheconsumingprocessviathebufferinventory.Partreplenishmentis“triggered”basedonconsumptionversusnetrequirements.Futurerequirementshelpestablishbuffersizing,notactualmaterialrelease.8

介紹補充拉系統(tǒng)在流程中關鍵的地方建立了零部件的緩沖區(qū).原材料制造零件采購零件成品通過緩沖庫存將供應過程和消耗過程聯(lián)系起來.零件的補充是基于消耗的實際需求而被觸發(fā)的.未來需求幫助確定緩沖量的大小，而不是決定于實際材料的發(fā)放.9ReplenishmentPullSystemBenefitsEfficiency:ApullsystemcanattainthesamethroughputasapushsystemwithlessaverageWIP(andtherefore,ashortercycletime).EaseofControl:PullsystemsrelyonsettingeasilycontrollableWIPlevels,versusreleaseratesforpushsystems(maintainingconstantthroughputismuchmoredifficult).Robustness:PullsystemperformanceisdegradedmuchlessbyerrorsinWIPlevelsthanbyacomparablepercenterrorinthroughput.QualityImprovement:LowWIP(andassociatedcycletime)systemsaremoresensitivetoquality(andthereforeforceproblemresolution)andfacilitateit(byimprovingfeedbackandlearningcycles).10補充拉系統(tǒng)的的好處效率:一個個拉系統(tǒng)可以以獲得和推系系統(tǒng)一樣的產產能而平均WIP水準卻更少(因此，周期時時間更短).易于控制:和和推系統(tǒng)的的放料相比，，拉系統(tǒng)依靠靠設置更容易易控制WIP水平(推系統(tǒng)難以保保證更持續(xù)穩(wěn)穩(wěn)定的產能).敏銳性:拉拉系統(tǒng)對比推推系統(tǒng)在同樣樣的WIP水平差錯更少少.質量改善:底WIP（與周期時間相相關聯(lián)）系統(tǒng)統(tǒng)對于質量（（因為要壓迫迫問題解決））更加敏感且且有助于推動動它（通過改改善反饋和學學習周期）.11ReplenishmentPullSystemDesignDriversComponentpartshavedifferent““characteristics”Dollarvolumevariesparttopart,drivesneedforpartstratification(impactsorderfrequency)Demandprofiles(peaksandvalleys),orvariability,isdifferentfordifferentpartsLeadtime(replenishmenttime)variesparttopartDemandisdynamicandchangesovertimeSeasonality,rampup/down,engineeringchangesdriveneedtoresizeKanbansystem(typicallymonthly)Designtrade-offsmanageriskSafetystock(designedasprotectionagainstvariability),reducespartshortagesbutincreasesinventoryHoldingsemi-finishedinventoryvolumesmoothesdemandatthatbuffer,butaddscycletime12補充拉系統(tǒng)的的設計驅動因因素各零部件具有有不同的“特特征”零件與零件間間的價值量不不同，使零件件需求層次不不同（影響訂訂貨頻率）需求輪廓（高高峰和低峰）），或變化因因零件不同而而不同交貨期（補充充時間）件與與件的不同需求是動態(tài)的的，且隨時間間的變化而變變化季節(jié)性的、需需求上升/下下降、工程變變更等需要調調整看板系統(tǒng)統(tǒng)（一般為月月度調整）設計協(xié)定，管管理風險安全庫存(為預防變化性性而設計),減少零件短缺缺但增加了庫庫存保留半成品庫庫存，雖然讓讓需求在緩沖沖區(qū)流動平滑滑，但是增加加了周期時間間13WhentoUseReplenishmentPullLeadtimeisgreaterthancustomerexpectationwindowRepetitiveproductofferingRelativelyconsistentdemand(lowvariability)Note:GenericPullsystemsshouldalwaysbeusedwhenareplenishmentpullsystemisimplemented.14何時使用補充充拉系統(tǒng)交貨期比客戶戶期望的大得得多反復性的產品品供應相對穩(wěn)定的需需求（底變異異）注:當補充拉拉系統(tǒng)被采用用時，普通拉拉系統(tǒng)必定也也是在使用的的.15ManufacturingPullvs.

PurchasePullKeyDifferencesPurchasePullSystemExternallycontrolledMultiplesuppliersandlocationsControlledbyminorderquantitiesContinualcommunicationtovendorstoaddresscostandshippingissuesRelianceonvendor(s)forshippingfrequencyandorderedquantitiesManufacturingPullSystemInternallycontrolledOnesupplierandonelocationControlledbymanufacturingprocessInternaldailycommunicationtoaddressissuesRelianceoninternalresourcesforchanges(quantities,priorityofshoporders,etc.)16制造拉系統(tǒng)和和采購拉系統(tǒng)統(tǒng)的主要不同同采購拉系統(tǒng)外部控制多個供應商和和供應位置以最小的訂單單數(shù)量控制不斷的與供應應商交流，忙忙于成本和交交貨事宜依賴于供貨方方的交貨頻率率和數(shù)量制造拉系統(tǒng)內部控制一個供應商和和一個供貨地地點通過制造流程程來控制內部的日常交交流來解決問問題依賴于內部資資源的變化（（質量、車間間內部指令等等）17ReplenishmentPullSystemParametersThereisvirtuallynodifferenceinthesupportingpullsystemcalculationsforthetwotypesofparts,butwepresentthemseparatelyforclarity.ManufacturingPullSystemsDemandManufacturingCycleTime(MCT)CycleTimeInterval(CTI)SafetyStock(SS)PurchasePullSystemDemandLeadTime(LT)OrderFrequency(OF)SafetyStock(SS)18補充拉系統(tǒng)的的參數(shù)事實上，對于于這兩種類型型的拉系統(tǒng)計計算并沒有本本質的區(qū)別，，這里為了識識別清楚而分分開制造拉系統(tǒng)需求制造周期時間間(MCT)周期時間間隔隔(CTI)安全庫存(SS)采購拉系統(tǒng)需求交貨期(LT)訂單頻率(OF)安全庫存(SS)19Manufacturing

PullSystems制造拉系統(tǒng)ManufacturingStrategicBuffer(On-Site)3-4WeekManufacturingCycleTime2Week“CustomerExpectation”ReplenishmentSignalConsumptionManufacturingPullSystemBasedonconsumptionOn-handquantityfunctionofdemandvariability,leadtime,orderfrequency,desiredservicelevelPartshortagesandexpeditingreducedInventoryreduced(bettermix)22生產制造戰(zhàn)略緩沖3-4周制造周期時間間2周“客戶戶的的期期望望””補充充信信號號消耗耗制造造拉拉系系統(tǒng)統(tǒng)補充充基基于于消消耗耗現(xiàn)有有數(shù)數(shù)量量與與需需求求變變量量、、交交貨貨時時間間、、訂訂單單頻頻次次、、期期望望的的服服務務水水平平成成函函數(shù)數(shù)關關系系零件件短短缺缺減減少少/消消除除庫存存減減少少（（更更合合理理的的產產品品組組合合））23ManufacturingPullSystemParametersDemand(averageweeklyoraveragedailyusage)Basedoneitherhistory,forecast(backlog)orcombinationRecalculatedfrequentlyinordertocapturechangesintrendsManufacturingCycleTime(MCT)Timefromwhenarelease(workorder)issenttothemanufacturingflooruntilpartsarereceived(replenishmenttime)CycleTimeInterval(CTI)Representsthefrequency(days),thataspecificpartismanufactured-drivestheorderquantity(batchsize)thatwewouldliketobuildChangingCTIallowstrade-offsbetweentransactions,capacityandinventorySafetyStock(SS)Partsrequiredtocompensateforvariation(i.e.,demand,quality,downtime)24制造造拉拉系系統(tǒng)統(tǒng)的的參參數(shù)數(shù)需求求(平均均每每周周或或平平均均每每天天的的用用量量AWU或ADU)基于于歷歷史史、、預預測測（（訂訂單單））或或兩兩者者的的結結合合多次計算算以掌握握變化的的趨勢制造周期期時間(MCT)從工單發(fā)發(fā)出到制制造車間間開始，，直到收收到零件件（補充充時間））的時間間周期時間間間隔(CTI)表示某一一零件的的制造頻頻率（天天），驅驅動我們們將要制制造的訂訂貨數(shù)量量（批數(shù)數(shù)量）改變CTI允許在交交易、能能力和庫庫存間平平衡安全庫存存(SS)為預防變變化（如如需求、、質量、、停機））而設置置的零件件需求25Demand(DMD)DMDistheusageoveraperiodoftime.Ensurethatthedemandiscalculatedinthesameunitsastheothercomponents(i.e.,weeks,days,etc.).Onehastobecarefulwhenusingonlyhistoricalusageforaveragedemandasitmaynotreflectcomingchangesinthebusiness-i.e.,productmix,volumeincreases,etc.Typically,somecombinationof:HistoricalUsageForecastedDemandLookAheadWindowareusedifthepartsseeseasonalityorothervolumeswings.DMDisusuallythemostdifficultnumbertopindowninpullcalculations.26需求(DMD)DMD是指某段時間間內的用量，，確保需求的的計算和其他他零件的計算算使用相同的的單位(如周、天等).需要注意的是是當用以往用用量做為平均均需求時，可可能不能反映映出未來的業(yè)業(yè)務變化-如如：產品種類類、需求量增增加時、一般般的應用組合合為：歷史的用量預測的需求未來的趨勢用來發(fā)現(xiàn)季節(jié)節(jié)性或其他原原因的產量變變化，DMD通常是拉系統(tǒng)統(tǒng)中計算最困困難的數(shù)據(jù).27ManufacturingCycleTime(MCT)MCTisthetimefromworkreleaseintothemanufacturingprocessuntilcompletion/movementintoshipping/finishedgoods.Itismeasuredas:ItisveryimportanttoconfirmthattheMCTcalculationaboveholdstrueviaasamplingofhistoricalworkorderdatafromtheshopfloor.28制造周期時間間(MCT)MCT是從工作指令令發(fā)出到制造造工序中，直直到完成后續(xù)續(xù)工序或成品品為止的時間間，計算如下下:這里非常重要要的一點是要要確認使用從從現(xiàn)場收集的的真實數(shù)據(jù)而而不是以往的的抽樣數(shù)據(jù).29MCTExits=30units/dayWIP=SumofallInventorywithinPhysicalworkarea=100unitsMCT=100units/30unitsperdayMCT=3.3daysManufacturingCycleTime(MCT)30MCTExits=30units/dayWIP=在實際工作區(qū)區(qū)域里的庫存存總數(shù)=100unitsMCT=100units/30unitsperdayMCT=3.3days制造周期時間間(MCT)31CycleTimeInterval(CTI)CTIisthefrequencythataspecificpartismanufactured(drivesbatchsizeororderquantity).Itismeasuredas:32周期時間間隔隔(CTI)CTI是某個零件被被生產的頻率率(驅動批數(shù)量或或訂單數(shù)量).計算如下:33ABACABCTI(A)CTI(B)RawMaterialFinishedGoods100100100DmdA=15units/dayBatchA=20YieldA=90%CTIACTI=(20unitsx.90)/15unitsperday=1.2daysCTIBCTI=(10unitsx.90)/10unitsperday=0.9daysCTICCTI=(15unitsx.95)/5unitsperday=2.85daysCalculatingCycleTimeInterval(CTI)DmdB=10units/dayBatchB=10YieldB=90%DmdC=5units/dayBatchC=15YieldC=95%34ABACABCTI(A)CTI(B)原材料成品100100100需求A=15units/day批A=20良品率A=90%CTIACTI=(20unitsx.90)/15unitsperday=1.2daysCTIBCTI=(10unitsx.90)/10unitsperday=0.9daysCTICCTI=(15unitsx.95)/5unitsperday=2.85days計算周期時間間間隔(CTI)需求B=10units/day批B=10良品率B=90%需求C=5units/day批C=15良品率C=95%35DemandDemandSafetyStock(SS)SSisproductrequiredtoguardagainst:ProcessVariabilityDemandVariabilityLeadTime/MCTVariabilityQualityProblems36DemandDemand安全庫存(SS)SS是為對付下列列情況的產品品需求而設定定的:過程變化需求變化交貨期/MCT變化質量問題37SafetyStock(SS)SSisafunctionof:Demandvariability(standarddeviation:)Desiredservicelevel(stockoutcoverage)ManufacturingCycleTime(MCT)Manufacturingon-timeperformance()Therearemanywaystocalculatesafetystock,wewilluseonebasedonempiricalcomputationsandexperience.KeyAssumption:Thedemandprofileisnormallydistributed.50%84%98%50%+50%+SafetyStock=*servicelevel*(MCT)where=0.7CoefficientVariation=s/x38安全庫存(SS)SS是下列因素的的函數(shù):需求變化(標準偏差:)期望的服務水水準(庫存不短缺的的覆蓋面積)制造周期時間間(MCT)制造時間的準準時率()有多種方法法計算安全全庫存，我我們這里使使用其中一一種經驗公公式.重要假定:需求形形式遵循正正態(tài)分布。。50%84%98%50%+50%+安全庫存=*服務水準準*(MCT)這里=0.7變異系數(shù)CV=s/x=Sigma/AverageDemand（CV<0.75,用數(shù)量計算算WIP，0.75-1.33,用等價物數(shù)數(shù)量或時間間，>1.33,用用時間表表示，詳見見W306GenericPullSystem章節(jié)縱軸是顧客客需求量橫軸是時間間序列39SafetyStock(SS):ServiceLevelServiceLevel:Theservicelevelisessentiallythenumberofstandarddeviations,relativetothemean,carriedassafetystock.Itis,literally,thecalculatednumberoftimesthatyouexpectastockouttooccur.50%84%98%DemandaboveandbelowthemeanServiceLevel=1meansthatonestandarddeviationofsafetystockiscarried,andonaveragetherewillbenostockouts84%ofthetime(50%belowmean+34%)ServiceLevel=2meansthattwostandarddeviationsofsafetystockiscarried,andonaveragetherewillbenostockouts98%ofthetime(50%belowmean+48%)andsoon...40安全庫存(SS):服務水平服務水平:服務水平本本質上指相相對需求平平均值而言言的標準差差的倍數(shù)，，在安全庫庫存中表示示.按字面理解解，就是你你認為出現(xiàn)現(xiàn)庫存短缺缺發(fā)生的時時間的計算算50%84%98%需求高于或或低于平均均值服務水準=1意指只有1個標準差差的庫存，，平均庫存存不出現(xiàn)短短缺的次數(shù)數(shù)將有84%（50%均值值以下+34%)服務水準=2意意指只有有2個標準準差的庫存存，平均庫庫存不出現(xiàn)現(xiàn)短缺的次次數(shù)將有98%（50%均值值以下+48%)等等41SafetyStock(SS):ServiceLevel42DateUsage4-Jan995-Jan1006-Jan1007-Jan998-Jan9811-Jan10012-Jan10113-Jan9914-Jan10215-Jan10318-Jan9919-Jan9820-Jan9721-Jan10022-Jan10125-Jan10226-Jan10427-Jan10128-Jan99UsageCount29-Jan989611-Feb989722-Feb969843-Feb1009964-Feb10210075-Feb10110168-Feb10310249-Feb102103210-Feb101104111-Feb10012-Feb99均值15-Feb101100.0316-Feb9717-Feb100標準差18-Feb991.8519-Feb102AverageDailyUsage929496981001021041061/4/011/11/011/18/011/25/012/1/012/8/012/15/01UnitsCountofUsages01234567896979899100101102103104Count安全庫存(SS):服務水平43SafetyStock(SS):ServiceLevelRecallthatweassumeourdemandcanberepresentedbyanormaldistribution:1=1.85=68.27%2=3.70=95.45%MeanBut,wearealwayscoveredwhendemandisLOWERthanthemean,soat:ServiceLevel=1whichis:

1*=68.27%/2+50.0%=84.14%Andat:ServiceLevel=2whichis:

2*=95.45%/2+50.0%=97.73%Tosummarize:ServiceLevel=1gives84%stockoutcoverageServiceLevel=2gives98%stockoutcoverageServiceLevelof1=84%stockoutcoverageServiceLevelof2=98%stockoutcoverage44安全庫存(SS):服務水平假定我們的的需求可以以用正態(tài)分分布1=1.85=68.27%2=3.70=95.45%均值值但是是，，當當需需求求比比平平均均值值低低時時，，我我們們總總是是出出現(xiàn)現(xiàn)短短缺缺，，所所以以:服務水平=1意意味著:

1*=68.27%/2+50.0%=84.14%在:服務水平=2意味著:

2*=95.45%/2+50.0%=97.73%總結:服務水平=1覆蓋蓋84%庫存不短缺服務水平=2覆蓋蓋98%庫存不短缺服務水平1=84%庫存短短缺率服務水平2=98%庫存短短缺率45BOHWorkOrders(SumWO)MCTMaxLoop*=(MCT*Dmd)+(CTI*Dmd)+SSMinKanban/TriggerPoint=(MCT*Dmd)+SSOrderIf:(BOH*+SumWO)<=TriggerPointOrderQty=MaxKanban-(BOH*+SumWO)CTISSMCTManufacturedPartsAvgBOH*BalanceOn-Hand(BOH)MaxLoop=MaxKanbanMaxMinBasicPullFormulasforManufacturedParts46現(xiàn)有余額=BOH訂單數(shù)量=OOQMCT最大看板數(shù)量量MaxLoop*=(MCT*Dmd)+(CTI*Dmd)+SS最小看板/觸發(fā)點MinKanban/TriggerPoint=(MCT*Dmd)+SS如果:(BOH*+SumWO)<=TriggerPoint觸發(fā)點時就生生產訂單數(shù)量=最大看板板數(shù)量-(BOH*+SumWO)CTISSMCT制造的零件AvgBOHBalanceOn-Hand(BOH)顧客過程中的的現(xiàn)有余量MaxLoop=MaxKanban最大看板數(shù)量量MaxMin制造件的拉系系統(tǒng)基本公式式47OtherKeyParametersforManufacturedPartsBatchSizePerformanalyticalbatchsizingEnsurepulldesignmeetscapacitylimitationsofprocessMinimum/Maximum/MultipleOrderQuantitiesChallengebasedonBatchSizingandcapacityanalysisaboveMaybebaseduponcontainerquantity–caution48制造零件的其其他關鍵參數(shù)數(shù)批量實施批數(shù)量的的分析確保拉動設計計滿足過程的的能力限制最小/最大/多訂單數(shù)量基于以上批量量和能力分析析而挑戰(zhàn)還可能基于容容器數(shù)量–警戒49Example:ManufacturingReplenishmentPullSystemPartNumber“XYZ”hasthefollowingdata:CTI =15daysMCT =30daysSafetyStock =100partsDemand =4.0parts/dayDeterminetheMaxLoop(Kmax)MaxLoop=(MCTxDemand)+(CTIxDemand)+SS=(____x_______)+(___x_______)+(__)=__________50舉例:制造補充拉系系統(tǒng)零件“XYZ”已經有了如下下數(shù)據(jù):CTI =15天MCT =30天安全庫存= 100個需求 =4.0個個/天決定最大看板板數(shù)(Kmax)MaxLoop=(MCTxDemand)+(CTIxDemand)+SS=(____x_______)+(___x_______)+(__)=__________51PurchasePullSystems采購拉系統(tǒng)StrategicBuffer(on-site)8WeekVendorLeadTime1-2WeekManufacturingCycleTime2Week“CustomerExpectation”ReplenishmentSignal““PurchaseOrder”ConsumptionVendorManufacturingPurchasePullSystemBasedonconsumptionOn-handquantityfunctionofdemandvariability,leadtime,orderfrequency,desiredservicelevelPartshortagesreduced/eliminated(reducingexpediting)Inventoryreduced(bettermix)54戰(zhàn)略緩沖(on-site)8周供應商交貨期期1-2周制造周期時間間2周“客戶期望”補充信號：““采購訂單””消耗供應商制造流程采購拉系統(tǒng)補充基于消耗耗現(xiàn)有數(shù)量與需需求變量、交交貨時間、訂訂單頻次、期期望的服務水水平成函數(shù)關關系零件短短缺減減少/消除除庫存減減少（（更合合理的的產品品組合合）55PurchasePullSystemParametersDemand(averageweeklyordailyusage)Basedoneitherhistory,forecast(backlog)orcombinationRecalculatedfrequentlyinordertocapturechangesintrendsLeadTime(LT)Timefromwhenarelease(PO)issenttothesupplieruntilpartsarereceived(replenishmenttime)OrderFrequency(OF)Representstheorderfrequency(days),ororderquantity(units)thatwewouldliketopurchaseChangingOFallowstrade-offsbetweentransactions,capacityandinventorySafetyStock(SS)Partsrequiredtocompensateforvariation(I.e.demand,quality,vendordelivery)56PurchasePullSystemParameters需求(平均每每周或或平均均每天天的用用量)基于歷歷史、、預測測（訂訂單））或兩兩者的的結合合多次計計算以以掌握握變化化的趨趨勢交貨期期(LT)從發(fā)出出一個個訂單單給供供應商商到零零件接接受的的時間間（補補充時時間））訂單頻頻率(OF)表現(xiàn)我我們所所喜歡歡的訂訂單的的頻率率（天天）,或訂單單的數(shù)數(shù)量（（單位位）改變訂訂單的的頻率率可以以使訂訂單處處理、、能力力和庫庫存之之間有有一定定的緩緩沖余余地安全庫庫存(SS)用于應應付變變化（（如：：需求求量、、質量量、供供應商商交付付等））的零零件需需求57LTisthetimetoreplenishapartfromasupplieroncetheparthasbeenconsumed.Itshouldinclude:POGeneration+SupplierLT+Transportation+Receiving/InspectionOFisthefrequencythataspecificpartisordered(drivesorderquantity)SupplierLeadTime(LT)andOrderFrequency(OF)GenerateandMail/FaxPOReceiveandLog/EnterPOPrepareandShipProductTransportProductReceiveandInspectProductLT58LT是從供供應商商那里里補充充零件件直到到該零零件被被消耗耗的時時間，，包括括以下下內容容：PO生成+供應商LT+運輸+接受受/檢檢驗OF是指某一一零件的的訂貨頻頻次（決決定驅動動定貨數(shù)數(shù)量的變變化）供應商交交貨期(LT)和

訂單單頻率(OF)產生和Mail/FaxPO供應商收收到并記記錄/輸輸入PO供應商準準備及發(fā)發(fā)運貨物物產品運輸輸收料和產品檢驗驗LT59PartClassificationdrivesa64%reductionintransactions,with12.5%lessinventory!OrderFrequencyABCPartClassificationManytimesitisfinanciallyadvantageoustosetdifferentorderfrequenciesfordifferent““classes””ofparts.ThisisusuallyperformedviathePareto(80/20)Analysisusingstandardand/orextendedcosts:60零件分類類法讓事事務處理理量被減減少64%，庫庫存被減減少12.5%訂單頻率率ABC零件分類類大多數(shù)情情況下，，出于財財務考慮慮/根據(jù)據(jù)不同零零件“分分類”設設定為為不同的的訂貨頻頻次，一一般采用用柏拉圖圖（80/20）分析析，其標標準/附附加成本本：61PurchasePartSafetyStockSizingSSisafunctionof:Demandvariability()DesiredservicelevelSupplierleadtime(LT)Supplieron-timeperformance()KeyAssumption:Thedemandprofileisnormallydistributed.50%84%98%CoefficientVariation=s/xSafetyStock=*servicelevel*(MCT)where=0.762采購件的的安全庫庫存規(guī)模模SS是以下內內容的函函數(shù):需求變化化()期望的服服務水平平供應商交交貨時間間(LT)供應商準準時交貨貨表現(xiàn)()重要假設設:需求的曲曲線呈正正態(tài)分布布50%84%98%變量系數(shù)數(shù)=s/x安全庫存存=*服務水水平*(MCT)這里=0.763PurchaseLeadTimeand

On-TimePerformance50%84%98%Unitsperweek(demand)SafetyStock=*servicelevel*(LT)Example:Threepartshavethesamevariability(s/x=1.2),andastandarddeviationof75.PartAhasaleadtimeof5days,PartBhasaLTof20days,whilePartChasaleadtimeof40days.Assumingadesiredservicelevelof98%and=0.7,whatistherequiredsafetystockofeach?Answer:SSA=75x2x(5^.7)=462unitsSSB=75x2x(20^.7)=1221unitsSSC=75x2x(40^.7)=1984unitsLeadtimereductionbecomesacrucialpartofaninventorymanagementstrategy!64采購交貨貨期和按按時交交貨表現(xiàn)現(xiàn)50%84%98%件每周(需需求)安全庫存存=*服務水水平*(LT)舉例:三種零件件有相同同的變量量系數(shù)(s/x=1.2),標準差為為75.零件A的交貨時時間是5天,零件B的交貨時時間是20天,零件C的交貨時時間為40天.假設期望望的服務務水平為為98%，，=0.7,那么每種種零件要要求的安安全庫存存是多少少?回答:SSA=75x2x(5^.7)=462unitsSSB=75x2x(20^.7)=1221unitsSSC=75x2x(40^.7)=1984units減少交貨貨時間成成為庫存存管理策策略的關關鍵部分分65DemandVariability:ImpactonSafetyStockHowmuchsafetystockisrequiredofeachitem,givenadesiredfillrateof98%?(assumethereplenishmentleadtimeis5daysforallparts)ADUA=15StdDevA=75SSA=____units(safetystockalgorithm)____units/15units/day=___daysSSADUB=10StdDevB=75SSB=____units(safetystockalgorithm)____units/10units/day=___daysSSADUC=5StdDevC=75SSC=____units(safetystockalgorithm)____units/5units/day=___daysSSTypicalapproachattemptstomaintainasimilarinventoryonallitems.Thisapproachdrivestoomuchinventoryonsome,andnotenoughonothers.DemandProfile66需求的可變變性:對對安全庫存存的影響對于每項產產品需要多多少安全庫庫存？,給給定98%的期望望供給率？？(假設對于每每項產品的的補充交貨貨時間為5天)ADUA=15標準差A=75SSA=____件(安安全庫存計計算式)____件/15件/天=___天SSADUB=10標準差B=75SSB=____件(安安全庫存計計算式)____件/10件/天=___天SSADUC=5標準差C=75SSC=____件(安全庫存存計算式)____件/5件/天=___天SS一般的方法法是對所有有的產品項項目盡量保保持同樣的的庫存.這這種方方法可能對對某些產品品來說庫存存太多，而而對另外的的產品又不不夠。需求變化圖圖67BasicPullFormulasforPurchasedPartsBOHPurchasedOrders(SumPO)SLTMaxLoop*=(LT*Dmd)+(OF*Dmd)+SSMinKanban/TriggerPoint=(LT*Dmd)+SSOrderIf:(BOH*+SumPO)<=TriggerPointOrderQty=MaxKanban–(BOH*+SumPO)OFSSLTPurchasedPartsAvgBOH*BalanceOn-Hand(BOH)MaxLoop=MaxKanbanMaxMin68采購零件拉拉系統(tǒng)的基基本公式現(xiàn)存余額BOH采購定單SLTMaxLoop*（拉系統(tǒng)環(huán)里里的最大庫庫存）=(LT*Dmd)+(OF*Dmd)+SSMinKanban/TriggerPoint拉系統(tǒng)環(huán)里里的最小庫庫存/觸發(fā)發(fā)點=(LT*Dmd)+SS如果:(BOH*+SumPO)<=TriggerPoint觸發(fā)點時就就訂貨訂單數(shù)量=MaxKanban–(BOH*+SumPO)OFSSLT采購的零件件AvgBOH*BalanceOn-Hand(BOH)策略緩沖中中的庫存數(shù)數(shù)量MaxLoop=MaxKanbanMaxMin69Example#1:PurchasePullSystemPurchasePartNumber““11111”hasthefollowingdata:OF =10daysLT =20daysSafetyStock=50partsDemand=2.0parts/dayDeterminetheMaxLoop(Kmax)MaxLoop=(OFxDemand)+(LTxDemand)+SS=(____x______)+(___x______)+(__)=________DeterminetheMinKanban/TriggerPoint(Kmin)MinKanban=(LTxDemand)+SS=(___x______)+(__)=________BONUSQUESTION:IftheBOH=50partsandtheSumPO’’s=50parts,shouldwereplenishandifsohowmuch?70舉例例#1:采購購拉拉系系統(tǒng)統(tǒng)采購購件件““11111””已已知知以以下下數(shù)數(shù)據(jù)據(jù):OF=10天LT=20天安全全庫庫存存=50天天需求求=2.0件件/天天決定最大看板板數(shù)量(Kmax)MaxLoop=(OFx需求)+(LTx需求)+SS=(____x______)+(___x______)+(__)=________決定最小看板板數(shù)量/觸觸發(fā)點(Kmin)MinKanban=(LTx需求)+SS=(___x______)+(__)=________有獎問答:如如果BOH=50件，SumPO’’s=50件,我們要要補充嗎？如如果要，補充充多少？71舉例#1:采購拉系統(tǒng)（（答案）采購件“11111””已知以下下數(shù)據(jù):OF =10天LT =20天安全庫存= 50天天需求 =2.0件件/天決定最大看板板數(shù)量(Kmax)MaxLoop=(OFx需求)+(LTx需求)+SS=(_10_x__2__)+(_20__x__2___)+(50*2)=___160_____決定最小看板板數(shù)量/觸觸發(fā)點(Kmin)MinKanban=(LTx需求)+SS=(_20_x___2__)+(50*2)=___140____有獎問答:如如果BOH=50件，SumPO’’s=50件,我們要要補充嗎？50+50<140,需需要補充160-50-50=60，72Usingthedataonthepreviousslide,calculate

thefollowing:WhatistheHighestBufferInventory?______WhatistheLowestBufferInventory?______SSQuantityLTQuantity__________________TriggerPointBuffer

MaxLoopOFQuantityExample#1:PurchasePullSystem(Cont.)73用前面的數(shù)據(jù)據(jù)，計算下列列：最高的緩沖庫庫存是多少?______最低的緩沖庫庫存是多少?______SS數(shù)量LT數(shù)量__________________觸發(fā)點緩沖

MaxLoopOF數(shù)量舉例#1:采購拉系統(tǒng)74Demand=7parts/daySafetyStock(SS)=10partsVendorLeadTime(LT)=10daysOrderFrequency(OF)=5daysExample#2:PurchasePullSystemSSQuantityLTQuantity__________________TriggerPointBuffer

MaxLoopOFQuantityUsingthedatatotheleft,calculatethefollowing:Whatisthevendorleadtimequantity=________?Whatisthetriggerpoint=_________?Whatisthetypicalorderquantity=________?Whatisthetypical(avg)BOH(bufferinventory)=_________?75需求=7件/天天安全庫存(SS)=10件供應商交貨期期(LT)=10天訂單頻率(OF)=5天舉例#2:采購拉系統(tǒng)SS數(shù)量LT數(shù)量__________________觸發(fā)點緩沖

MaxLoopOF數(shù)量用左邊的數(shù)值值計算下列：：供應商的交貨貨期數(shù)量是多多少=________?觸發(fā)點是多少少=_________?典型的訂貨數(shù)數(shù)量是多少=________?典型的(平平均)BOH(緩沖庫存)是是多少=_________?76需求=7件/天天安全庫存(SS)=10件供應商交貨期期(LT)=10天訂單頻率(OF)=5天舉例#2:采購拉系統(tǒng)SS數(shù)量LT數(shù)量__________________觸發(fā)點緩沖

MaxLoopOF數(shù)量用左邊的數(shù)值值計算下列：：供應商的交貨貨期數(shù)量是多多少=__7*10______?觸發(fā)點是多少少=___7*10+10______?典型的訂貨數(shù)數(shù)量是多少=__5*7______?典型的(平平均)BOH(緩沖庫存)是是多少=7*10+10?77PullSystemsPullSystemPlatformsManualvs.ElectronicPullSystems:HandlingSeasonalityPerformanceMeasures拉系統(tǒng)拉系統(tǒng)平臺人工VS電子拉系統(tǒng):處處理季節(jié)性績效量測PullSystemPlatformsVisualCardSystemsElectronicSystems2-Bin/AsynchronousSynchronous80拉系統(tǒng)統(tǒng)平臺臺目視卡卡系統(tǒng)統(tǒng)電子系系統(tǒng)2-Bin/不同步步的同步的的81目視卡卡系統(tǒng)統(tǒng)該方法法使用用卡片片流經經整個個制造造過程程，并并返回回到拉拉系統(tǒng)統(tǒng)板上上通過過目光光就可可以看看到零零件的的情況況82ReplenishmentPullDemandCalculationPartsClassificationABCClassificationSafetyStockCalculationsOrderFrequencySystemPlatformPCBasedModulesElectronicThisapproachuseselectronicsystem(typicallyintegratedwithMRP)toresizepartquantitiesandtogeneratereplenishmentsignalswithouttheuseofcards.83補充充拉拉系統(tǒng)統(tǒng)需求求計計算算零件件分分類類ABC分類類安全全庫庫存存計計算算訂單單的的頻率率問題題解解答答績效效監(jiān)監(jiān)督督系統(tǒng)統(tǒng)平平臺臺基于于模模塊塊化化的的PC電子子的的該方方法法使使用用電電子子系系統(tǒng)統(tǒng)(一一般般都都與與MRP集成成)來調調整整零零件件庫庫存存的的大大小小規(guī)規(guī)模模，，產產生生補補充充信信號號，，而而不不需需要要用用卡卡片片84PrimaryStorage12LineSide12-Bin/AsynchronousEmptybinreturnstoprimarystorageBinisfilledFullbinreturnstoline85初始的庫庫存12生產線側側12-Bin/異步的空箱回到到初始庫庫存處箱子被填填滿填滿的箱箱子回到到生產線線上86AssemblyA2daysAssemblyB2daysAssemblyC2daysAssemblyD2daysSubAssyY6days8DayCycleTimeSubAssyX2daysSynchronousPull87組裝A2天組裝B2天組裝C2天組裝D2天半成品Y6天8天的的周期時時間半成品X2天同步的拉拉系統(tǒng)88Manualvs.ElectronicPullSystemsFewpartnumbersSteady/predictabledemandFewsuppliersFrequent(daily)deliversfromsuppliersVerydisciplinedworkforceManypartnumbersErraticorseasonaldemandManysuppliersInfrequentdeliveriesfromsuppliersDisciplinedworkforce/accurateinventoryFewpartnumbersSteady/predictabledemandSimpleprocessflowLimitedvariationinstandardpacksizeVerydisciplinedworkforceManypartnumbersErraticorseasonaldemandComplexprocessflowManyvariationsinstandardpacksizeDisciplinedworkforce/accurateinventoryPurchasingManufacturingNote:CombinationofElectronicandManualisacceptableManualElectronic89人工VS電子的拉拉系統(tǒng)零件數(shù)量量少穩(wěn)定的/可預測測的需求求少數(shù)幾個個供應商商頻繁的(每日)發(fā)貨從供供應商良好培訓訓的工人人很多零件件數(shù)量不確定的的或季節(jié)節(jié)性的需需求很多供應應商很少的交交貨從供供應商良好培訓訓的工人人/準確確的庫存存零件數(shù)量量少穩(wěn)定的/可預測測的需求求簡單的流流程標準包裝裝限制變變化良好培訓訓的工人人很多零件件數(shù)量不確定的或季季節(jié)性的需求求復雜的流程標準包裝變化化很大良好培訓的工工人/準準確的庫存采購制造Note: