精益生產(chǎn)之補(bǔ)充拉系統(tǒng)ReplenishmentPullSystems中英課件

Replenishment

PullSystemsManufacturingPullSystemsPurchasePullSystemsBufferLocationsPullSystemPlatformsManualvs.ElectronicPullSystems:HandlingSeasonalityPerformanceMeasuresAppendixRD010402Replenishment

PullSystemsMan補(bǔ)充拉系統(tǒng)制造拉系統(tǒng)采購(gòu)拉系統(tǒng)緩沖場(chǎng)所拉系統(tǒng)平臺(tái)手動(dòng)vs.電子拉系統(tǒng)：操作的季節(jié)性績(jī)效量測(cè)附錄RD010402補(bǔ)充拉系統(tǒng)制造拉系統(tǒng)RD010402LeanSixSigma

ImprovementProcessRoadMapAnalyzeControlImproveDefineIdentifyProblemDevelopListofCustomersDevelopListofCTQ’sfromVoiceoftheCustomerFinalizeProjectFocus

andKeyMetricsCompletePDFMeasureMapBusinessProcessMapValueStreamDevelopData

CollectionPlanConductMeasurement

SystemAnalysisCollectDataConductProcess

CapabilityAnalysisAnalyzeProposeCriticalX’sPrioritizeCriticalX’sVerifyCriticalX’sEstimatetheImpactofEachXonYQuantifytheOpportunityPrioritizeRootCausesConductRootCause

AnalysisonCriticalX’sImproveCriticalX’sConfirmedDevelopPotentialSolutionsSelectSolutionOptimizeSolutionPilotSolutionControlImplementProcess

ChangesandControlsWriteControlPlanCalculateFinalFinancial/ProcessMetricsTransitionProjecttoFutureOwnersIdentifyProjectTranslationOpportunitiesMeasureDefineProjectIDToolsProjectDefinitionFormNetPresentValueAnalysisInternalRateofReturnAnalysisDiscountedCashFlowAnalysisPIPManagementProcessRACIQuadChartsProcessMappingValueAnalysisBrainstormingMulti-VotingTechniquesParetoChartsC&E/FishboneDiagramsFMEACheckSheetsRunChartsControlChartsGageR&RCp&CpkSupplyChainAcceleratorAnalysisMulti-VariBoxPlotsInteractionPlotsRegressionANOVAC&EMatricesFMEABrainstormingPullSystemsSetupReductionTPMProcessFlowBenchmarkingAffinityDOEHypothesisTestingForceFieldTreeDiagramsGanttChartsCheckSheetsRunChartsHistogramsScatterDiagramsControlChartsParetoChartsInteractiveReviewsPoka-YokeRevised1-12-023ReplenishmentPullSystemsLeanSixSigma

ImprovementPrLearningObjectivesIntroductiontoReplenishmentPullSystemsLearnthebenefitsandapplicationsKnowthedifferencebetweenaManufacturingPullSystemvs.aPurchasePullSystemUnderstandkeyPullparametersandcalculationsIntroductiontothePullPlatformsKnowthekeybufferlocationswithinaprocess4ReplenishmentPullSystemsLearningObjectivesIntroductio學(xué)習(xí)目的介紹補(bǔ)充拉系統(tǒng)學(xué)習(xí)補(bǔ)充拉系統(tǒng)的好處和應(yīng)用了解制造拉系統(tǒng)和采購(gòu)拉系統(tǒng)的區(qū)別理解拉系統(tǒng)的關(guān)鍵參數(shù)及計(jì)算方法介紹拉系統(tǒng)的平臺(tái)了解流程中關(guān)鍵緩沖點(diǎn)的位置5ReplenishmentPullSystems學(xué)習(xí)目的介紹補(bǔ)充拉系統(tǒng)5ReplenishmentPullWhat’sinItforMe?UnderstandwhatReplenishmentPullisandmakeapplicationstoyourenvironmentGainunderstandingonthemanytypesofPullSystems6ReplenishmentPullSystemsWhat’sinItforMe?Understand我學(xué)到了什么?了解補(bǔ)充拉系統(tǒng)并并應(yīng)用于您的工作環(huán)境中對(duì)各種類(lèi)型的拉系統(tǒng)增進(jìn)了解7ReplenishmentPullSystems我學(xué)到了什么?了解補(bǔ)充拉系統(tǒng)并并應(yīng)用于您的工作環(huán)境中7Rep

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

IntroductionReplenishmentPul

介紹補(bǔ)充拉系統(tǒng)在流程中關(guān)鍵的地方建立了零部件的緩沖區(qū).原材料制造零件采購(gòu)零件成品通過(guò)緩沖庫(kù)存將供應(yīng)過(guò)程和消耗過(guò)程聯(lián)系起來(lái).零件的補(bǔ)充是基于消耗的實(shí)際需求而被觸發(fā)的.未來(lái)需求幫助確定緩沖量的大小，而不是決定于實(shí)際材料的發(fā)放.9ReplenishmentPullSystems

介紹補(bǔ)充拉系統(tǒng)在流程中關(guān)鍵的地方建立了零部件的緩沖區(qū).9RReplenishmentPullSystemBenefitsEfficiency:ApullsystemcanattainthesamethroughputasapushsystemwithlessaverageWIP(andtherefore,ashortercycletime).EaseofControl:PullsystemsrelyonsettingeasilycontrollableWIPlevels,versusreleaseratesforpushsystems(maintainingconstantthroughputismuchmoredifficult).Robustness:PullsystemperformanceisdegradedmuchlessbyerrorsinWIPlevelsthanbyacomparablepercenterrorinthroughput.QualityImprovement:LowWIP(andassociatedcycletime)systemsaremoresensitivetoquality(andthereforeforceproblemresolution)andfacilitateit(byimprovingfeedbackandlearningcycles).10ReplenishmentPullSystemsReplenishmentPullSystemBene補(bǔ)充拉系統(tǒng)的好處效率:一個(gè)拉系統(tǒng)可以獲得和推系統(tǒng)一樣的產(chǎn)能而平均WIP水準(zhǔn)卻更少(因此，周期時(shí)間更短).易于控制:和推系統(tǒng)的放料相比，拉系統(tǒng)依靠設(shè)置更容易控制WIP水平(推系統(tǒng)難以保證更持續(xù)穩(wěn)定的產(chǎn)能).敏銳性:拉系統(tǒng)對(duì)比推系統(tǒng)在同樣的WIP水平差錯(cuò)更少.質(zhì)量改善:底WIP（與周期時(shí)間相關(guān)聯(lián)）系統(tǒng)對(duì)于質(zhì)量（因?yàn)橐獕浩葐?wèn)題解決）更加敏感且有助于推動(dòng)它（通過(guò)改善反饋和學(xué)習(xí)周期）.11ReplenishmentPullSystems補(bǔ)充拉系統(tǒng)的好處效率:一個(gè)拉系統(tǒng)可以獲得和推系統(tǒng)一樣的產(chǎn)能ReplenishmentPullSystemDesignDriversComponentpartshavedifferent“characteristics”Dollarvolumevariesparttopart,drivesneedforpartstratification(impactsorderfrequency)Demandprofiles(peaksandvalleys),orvariability,isdifferentfordifferentpartsLeadtime(replenishmenttime)variesparttopartDemandisdynamicandchangesovertimeSeasonality,rampup/down,engineeringchangesdriveneedtoresizeKanbansystem(typicallymonthly)Designtrade-offsmanageriskSafetystock(designedasprotectionagainstvariability),reducespartshortagesbutincreasesinventoryHoldingsemi-finishedinventoryvolumesmoothesdemandatthatbuffer,butaddscycletime12ReplenishmentPullSystemsReplenishmentPullSystemDesi補(bǔ)充拉系統(tǒng)的設(shè)計(jì)驅(qū)動(dòng)因素各零部件具有不同的“特征”零件與零件間的價(jià)值量不同，使零件需求層次不同（影響訂貨頻率）需求輪廓（高峰和低峰），或變化因零件不同而不同交貨期（補(bǔ)充時(shí)間）件與件的不同需求是動(dòng)態(tài)的，且隨時(shí)間的變化而變化季節(jié)性的、需求上升/下降、工程變更等需要調(diào)整看板系統(tǒng)（一般為月度調(diào)整）設(shè)計(jì)協(xié)定，管理風(fēng)險(xiǎn)安全庫(kù)存(為預(yù)防變化性而設(shè)計(jì)),減少零件短缺但增加了庫(kù)存保留半成品庫(kù)存，雖然讓需求在緩沖區(qū)流動(dòng)平滑，但是增加了周期時(shí)間13ReplenishmentPullSystems補(bǔ)充拉系統(tǒng)的設(shè)計(jì)驅(qū)動(dòng)因素各零部件具有不同的“特征”13RepWhentoUseReplenishmentPullLeadtimeisgreaterthancustomerexpectationwindowRepetitiveproductofferingRelativelyconsistentdemand(lowvariability)

Note:GenericPullsystemsshouldalwaysbeusedwhenareplenishmentpullsystemisimplemented.14ReplenishmentPullSystemsWhentoUseReplenishmentPull何時(shí)使用補(bǔ)充拉系統(tǒng)交貨期比客戶期望的大得多反復(fù)性的產(chǎn)品供應(yīng)相對(duì)穩(wěn)定的需求（底變異）

注:當(dāng)補(bǔ)充拉系統(tǒng)被采用時(shí)，普通拉系統(tǒng)必定也是在使用的.15ReplenishmentPullSystems何時(shí)使用補(bǔ)充拉系統(tǒng)交貨期比客戶期望的大得多15RepleniManufacturingPullvs.

PurchasePullKeyDifferencesPurchasePullSystemExternallycontrolledMultiplesuppliersandlocationsControlledbyminorderquantitiesContinualcommunicationtovendorstoaddresscostandshippingissuesRelianceonvendor(s)forshippingfrequencyandorderedquantitiesManufacturingPullSystemInternallycontrolledOnesupplierandonelocationControlledbymanufacturingprocessInternaldailycommunicationtoaddressissuesRelianceoninternalresourcesforchanges(quantities,priorityofshoporders,etc.)16ReplenishmentPullSystemsManufacturingPullvs.

Purcha制造拉系統(tǒng)和采購(gòu)拉系統(tǒng)的主要不同采購(gòu)拉系統(tǒng)外部控制多個(gè)供應(yīng)商和供應(yīng)位置以最小的訂單數(shù)量控制不斷的與供應(yīng)商交流，忙于成本和交貨事宜依賴于供貨方的交貨頻率和數(shù)量制造拉系統(tǒng)內(nèi)部控制一個(gè)供應(yīng)商和一個(gè)供貨地點(diǎn)通過(guò)制造流程來(lái)控制內(nèi)部的日常交流來(lái)解決問(wèn)題依賴于內(nèi)部資源的變化（質(zhì)量、車(chē)間內(nèi)部指令等）17ReplenishmentPullSystems制造拉系統(tǒng)和采購(gòu)拉系統(tǒng)的主要不同采購(gòu)拉系統(tǒng)制造拉系統(tǒng)17ReReplenishmentPullSystemParametersThereisvirtuallynodifferenceinthesupportingpullsystemcalculationsforthetwotypesofparts,butwepresentthemseparatelyforclarity.ManufacturingPullSystemsDemandManufacturingCycleTime(MCT)CycleTimeInterval(CTI)SafetyStock(SS)PurchasePullSystemDemandLeadTime(LT)OrderFrequency(OF)SafetyStock(SS)18ReplenishmentPullSystemsReplenishmentPullSystemPara補(bǔ)充拉系統(tǒng)的參數(shù)事實(shí)上，對(duì)于這兩種類(lèi)型的拉系統(tǒng)計(jì)算并沒(méi)有本質(zhì)的區(qū)別，這里為了識(shí)別清楚而分開(kāi)制造拉系統(tǒng)需求制造周期時(shí)間(MCT)周期時(shí)間間隔(CTI)安全庫(kù)存(SS)采購(gòu)拉系統(tǒng)需求交貨期(LT)訂單頻率(OF)安全庫(kù)存(SS)19ReplenishmentPullSystems補(bǔ)充拉系統(tǒng)的參數(shù)事實(shí)上，對(duì)于這兩種類(lèi)型的拉系統(tǒng)計(jì)算并沒(méi)有本質(zhì)Manufacturing

PullSystemsManufacturing

PullSystems制造拉系統(tǒng)制造拉系統(tǒng)ManufacturingStrategicBuffer(On-Site)3-4WeekManufacturingCycleTime2Week“CustomerExpectation”ReplenishmentSignalConsumptionManufacturingPullSystemBasedonconsumptionOn-handquantityfunctionofdemandvariability,leadtime,orderfrequency,desiredservicelevelPartshortagesandexpeditingreducedInventoryreduced(bettermix)22ReplenishmentPullSystemsManufacturingStrategic3-4Week生產(chǎn)制造戰(zhàn)略緩沖3-4周制造周期時(shí)間2周“客戶的期望”補(bǔ)充信號(hào)消耗制造拉系統(tǒng)補(bǔ)充基于消耗現(xiàn)有數(shù)量與需求變量、交貨時(shí)間、訂單頻次、期望的服務(wù)水平成函數(shù)關(guān)系零件短缺減少/消除

庫(kù)存減少（更合理的產(chǎn)品組合）23ReplenishmentPullSystems生產(chǎn)制造戰(zhàn)略緩沖3-4周2周補(bǔ)充信號(hào)消耗制造拉系統(tǒng)補(bǔ)充ManufacturingPullSystemParametersDemand(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)24ReplenishmentPullSystemsManufacturingPullSystemPara制造拉系統(tǒng)的參數(shù)需求(平均每周或平均每天的用量AWU或ADU)基于歷史、預(yù)測(cè)（訂單）或兩者的結(jié)合多次計(jì)算以掌握變化的趨勢(shì)制造周期時(shí)間(MCT)從工單發(fā)出到制造車(chē)間開(kāi)始，直到收到零件（補(bǔ)充時(shí)間）的時(shí)間周期時(shí)間間隔(CTI)表示某一零件的制造頻率（天），驅(qū)動(dòng)我們將要制造的訂貨數(shù)量（批數(shù)量）改變CTI允許在交易、能力和庫(kù)存間平衡安全庫(kù)存(SS)為預(yù)防變化（如需求、質(zhì)量、停機(jī)）而設(shè)置的零件需求25ReplenishmentPullSystems制造拉系統(tǒng)的參數(shù)需求(平均每周或平均每天的用量AWU或ADDemand(DMD)DMDistheusageoveraperiodoftime.Ensurethatthedemandiscalculatedinthesameunitsastheothercomponents(i.e.,weeks,days,etc.).Onehastobecarefulwhenusingonlyhistoricalusageforaveragedemandasitmaynotreflectcomingchangesinthebusiness-i.e.,productmix,volumeincreases,etc.Typically,somecombinationof:HistoricalUsageForecastedDemandLookAheadWindowareusedifthepartsseeseasonalityorothervolumeswings.DMDisusuallythemostdifficultnumbertopindowninpullcalculations.26ReplenishmentPullSystemsDemand(DMD)DMDistheusageo需求(DMD)DMD是指某段時(shí)間內(nèi)的用量，確保需求的計(jì)算和其他零件的計(jì)算使用相同的單位(如周、天等).需要注意的是當(dāng)用以往用量做為平均需求時(shí)，可能不能反映出未來(lái)的業(yè)務(wù)變化-如：產(chǎn)品種類(lèi)、需求量增加時(shí)、一般的應(yīng)用組合為：歷史的用量預(yù)測(cè)的需求未來(lái)的趨勢(shì)用來(lái)發(fā)現(xiàn)季節(jié)性或其他原因的產(chǎn)量變化，DMD通常是拉系統(tǒng)中計(jì)算最困難的數(shù)據(jù).27ReplenishmentPullSystems需求(DMD)DMD是指某段時(shí)間內(nèi)的用量，確保需求的計(jì)算和

ManufacturingCycleTime(MCT)MCTisthetimefromworkreleaseintothemanufacturingprocessuntilcompletion/movementintoshipping/finishedgoods.Itismeasuredas:ItisveryimportanttoconfirmthattheMCTcalculationaboveholdstrueviaasamplingofhistoricalworkorderdatafromtheshopfloor.28ReplenishmentPullSystemsManufacturingCycleTime(MCT制造周期時(shí)間(MCT)MCT是從工作指令發(fā)出到制造工序中，直到完成后續(xù)工序或成品為止的時(shí)間，計(jì)算如下:這里非常重要的一點(diǎn)是要確認(rèn)使用從現(xiàn)場(chǎng)收集的真實(shí)數(shù)據(jù)而不是以往的抽樣數(shù)據(jù).29ReplenishmentPullSystems制造周期時(shí)間(MCT)MCT是從工作指令發(fā)出到制造工序MCTExits=30units/dayWIP=SumofallInventorywithinPhysicalworkarea=100unitsMCT=100units/30unitsperdayMCT=3.3days

ManufacturingCycleTime(MCT)30ReplenishmentPullSystemsMCTExits=WIP=SumofallInMCTExits=30units/dayWIP=在實(shí)際工作區(qū)域里的庫(kù)存總數(shù)=100unitsMCT=100units/30unitsperdayMCT=3.3days制造周期時(shí)間(MCT)31ReplenishmentPullSystemsMCTExits=WIP=在實(shí)際工作區(qū)域里的庫(kù)存總數(shù)CycleTimeInterval(CTI)CTIisthefrequencythataspecificpartismanufactured(drivesbatchsizeororderquantity).Itismeasuredas:32ReplenishmentPullSystemsCycleTimeInterval(CTI)CTIi周期時(shí)間間隔(CTI)CTI是某個(gè)零件被生產(chǎn)的頻率(驅(qū)動(dòng)批數(shù)量或訂單數(shù)量).計(jì)算如下:33ReplenishmentPullSystems周期時(shí)間間隔(CTI)CTI是某個(gè)零件被生產(chǎn)的頻率(驅(qū)ABACABCTI(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%34ReplenishmentPullSystemsABACABCTI(A)CTI(B)RawFinishABACABCTI(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(jì)算周期時(shí)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%35ReplenishmentPullSystemsABACABCTI(A)CTI(B)原材料成品10010DemandDemandSafetyStock(SS)SSisproductrequiredtoguardagainst:ProcessVariabilityDemandVariabilityLeadTime/MCTVariabilityQualityProblems36ReplenishmentPullSystemsDemandDemandSafetyStock(SS)DemandDemand安全庫(kù)存(SS)SS是為對(duì)付下列情況的產(chǎn)品需求而設(shè)定的:過(guò)程變化需求變化交貨期/MCT變化質(zhì)量問(wèn)題37ReplenishmentPullSystemsDemandDemand安全庫(kù)存(SS)SS是為對(duì)付下列SafetyStock(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/x38ReplenishmentPullSystemsSafetyStock(SS)SSisafunc安全庫(kù)存(SS)SS是下列因素的函數(shù):需求變化(標(biāo)準(zhǔn)偏差:)期望的服務(wù)水準(zhǔn)(庫(kù)存不短缺的覆蓋面積)制造周期時(shí)間(MCT)制造時(shí)間的準(zhǔn)時(shí)率()有多種方法計(jì)算安全庫(kù)存，我們這里使用其中一種經(jīng)驗(yàn)公式.重要假定:需求形式遵循正態(tài)分布。50%84%98%50%+50%+安全庫(kù)存=*服務(wù)水準(zhǔn)*(MCT)這里=0.7變異系數(shù)CV=s/x=Sigma/AverageDemand（CV<0.75,用數(shù)量計(jì)算WIP，0.75-1.33,用等價(jià)物數(shù)量或時(shí)間，>1.33,用時(shí)間表示，詳見(jiàn)W306GenericPullSystem章節(jié)縱軸是顧客需求量橫軸是時(shí)間序列39ReplenishmentPullSystems安全庫(kù)存(SS)SS是下列因素的函數(shù):50%84%98SafetyStock(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...40ReplenishmentPullSystemsSafetyStock(SS):ServiceLev安全庫(kù)存(SS):服務(wù)水平服務(wù)水平:服務(wù)水平本質(zhì)上指相對(duì)需求平均值而言的標(biāo)準(zhǔn)差的倍數(shù)，在安全庫(kù)存中表示.按字面理解，就是你認(rèn)為出現(xiàn)庫(kù)存短缺發(fā)生的時(shí)間的計(jì)算50%84%98%需求高于或低于平均值服務(wù)水準(zhǔn)=1意指只有1個(gè)標(biāo)準(zhǔn)差的庫(kù)存，平均庫(kù)存不出現(xiàn)短缺的次數(shù)將有84%（50%均值以下+34%)服務(wù)水準(zhǔn)=2意指只有2個(gè)標(biāo)準(zhǔn)差的庫(kù)存，平均庫(kù)存不出現(xiàn)短缺的次數(shù)將有98%（

50%均值以下+48%)等等41ReplenishmentPullSystems安全庫(kù)存(SS):服務(wù)水平服務(wù)水平:50%84%98%SafetyStock(SS):ServiceLevel42ReplenishmentPullSystemsSafetyStock(SS):ServiceLevDateUsage4-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(biāo)準(zhǔn)差18-Feb991.8519-Feb102AverageDailyUsage929496981001021041061/4/011/11/011/18/011/25/012/1/012/8/012/15/01UnitsCountofUsages01234567896979899100101102103104Count安全庫(kù)存(SS):服務(wù)水平43ReplenishmentPullSystemsDateUsage4-Jan995-Jan1006-Jan1SafetyStock(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%stockoutcoverage44ReplenishmentPullSystemsSafetyStock(SS):ServiceLev安全庫(kù)存(SS):服務(wù)水平

假定我們的需求可以用正態(tài)分布1=1.85=68.27%2=3.70=95.45%均值但是，當(dāng)需求比平均值低時(shí)，我們總是出現(xiàn)短缺，所以:服務(wù)水平=1意味著:

1*=68.27%/2+50.0%=84.14%在:服務(wù)水平=2意味著:

2*=95.45%/2+50.0%=97.73%總結(jié):服務(wù)水平=1覆蓋84%

庫(kù)存不短缺服務(wù)水平=2覆蓋98%

庫(kù)存不短缺服務(wù)水平1=84%庫(kù)存短缺率服務(wù)水平2=98%庫(kù)存短缺率45ReplenishmentPullSystems安全庫(kù)存(SS):服務(wù)水平假定我們的需求可以用正態(tài)分布BOHWorkOrders(SumWO)MCTMaxLoop*=(MCT*Dmd)+(CTI*Dmd)+SSMinKanban/TriggerPoint=(MCT*Dmd)+SSOrderIf:(BOH*+SumWO)<=TriggerPointOrderQty=MaxKanban-(BOH*+SumWO)CTISSMCTManufacturedPartsAvgBOH* BalanceOn-Hand(BOH) MaxLoop=MaxKanbanMaxMinBasicPullFormulasforManufacturedParts46ReplenishmentPullSystemsBOHWorkOrders(SumWO)MCTMaxL現(xiàn)有余額=BOH訂單數(shù)量=OOQMCT最大看板數(shù)量MaxLoop*=(MCT*Dmd)+(CTI*Dmd)+SS最小看板/觸發(fā)點(diǎn)MinKanban/TriggerPoint=(MCT*Dmd)+SS如果:(BOH*+SumWO)<=TriggerPoint觸發(fā)點(diǎn)時(shí)就生產(chǎn)訂單數(shù)量=最大看板數(shù)量-(BOH*+SumWO)CTISSMCT制造的零件AvgBOHBalanceOn-Hand(BOH)顧客過(guò)程中的現(xiàn)有余量MaxLoop=MaxKanban最大看板數(shù)量MaxMin制造件的拉系統(tǒng)基本公式47ReplenishmentPullSystems現(xiàn)有余額訂單數(shù)量=OOQMCT最大看板數(shù)量MaxLoopOtherKeyParametersfor

ManufacturedPartsBatchSizePerformanalyticalbatchsizingEnsurepulldesignmeetscapacitylimitationsofprocessMinimum/Maximum/MultipleOrderQuantitiesChallengebasedonBatchSizingandcapacityanalysisaboveMaybebaseduponcontainerquantity–caution48ReplenishmentPullSystemsOtherKeyParametersfor

Manu制造零件的其他關(guān)鍵參數(shù)批量實(shí)施批數(shù)量的分析確保拉動(dòng)設(shè)計(jì)滿足過(guò)程的能力限制最小/最大/多訂單數(shù)量基于以上批量和能力分析而挑戰(zhàn)還可能基于容器數(shù)量–警戒49ReplenishmentPullSystems制造零件的其他關(guān)鍵參數(shù)批量49ReplenishmentExample:

ManufacturingReplenishmentPullSystemPartNumber“XYZ”hasthefollowingdata:CTI = 15daysMCT = 30daysSafetyStock = 100partsDemand = 4.0parts/dayDeterminetheMaxLoop(Kmax)MaxLoop=(MCTxDemand)+(CTIxDemand)+SS=(____x_______)+(___x_______)+(__)=__________50ReplenishmentPullSystemsExample:

ManufacturingRepleni舉例:

制造補(bǔ)充拉系統(tǒng)零件“XYZ”已經(jīng)有了如下數(shù)據(jù):CTI = 15天MCT = 30天安全庫(kù)存 = 100個(gè)需求 = 4.0個(gè)/天決定最大看板數(shù)(Kmax)MaxLoop=(MCTxDemand)+(CTIxDemand)+SS=(____x_______)+(___x_______)+(__)=__________51ReplenishmentPullSystems舉例:

制造補(bǔ)充拉系統(tǒng)零件“XYZ”已經(jīng)有了如下數(shù)據(jù):5PurchasePullSystemsPurchasePullSystems采購(gòu)拉系統(tǒng)采購(gòu)拉系統(tǒng)StrategicBuffer(on-site)8WeekVendorLeadTime1-2WeekManufacturingCycleTime2Week“CustomerExpectation”ReplenishmentSignal“PurchaseOrder”ConsumptionVendorManufacturingPurchasePullSystemBasedonconsumptionOn-handquantityfunctionofdemandvariability,leadtime,orderfrequency,desiredservicelevelPartshortagesreduced/eliminated(reducingexpediting)Inventoryreduced(bettermix)54ReplenishmentPullSystemsStrategic8Week1-2Week2WeekR戰(zhàn)略緩沖(on-site)8周供應(yīng)商交貨期1-2周制造周期時(shí)間2周“客戶期望”補(bǔ)充信號(hào)：“采購(gòu)訂單”消耗供應(yīng)商制造流程采購(gòu)拉系統(tǒng)補(bǔ)充基于消耗現(xiàn)有數(shù)量與需求變量、交貨時(shí)間、訂單頻次、期望的服務(wù)水平成函數(shù)關(guān)系零件短缺減少/消除

庫(kù)存減少（更合理的產(chǎn)品組合）55ReplenishmentPullSystems戰(zhàn)略緩沖8周1-2周2周補(bǔ)充信號(hào)：“采購(gòu)訂單”消耗供應(yīng)PurchasePullSystemParametersDemand(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)56ReplenishmentPullSystemsPurchasePullSystemParameterPurchasePullSystemParameters需求(平均每周或平均每天的用量)基于歷史、預(yù)測(cè)（訂單）或兩者的結(jié)合多次計(jì)算以掌握變化的趨勢(shì)交貨期(LT)從發(fā)出一個(gè)訂單給供應(yīng)商到零件接受的時(shí)間（補(bǔ)充時(shí)間）訂單頻率(OF)表現(xiàn)我們所喜歡的訂單的頻率（天）,或訂單的數(shù)量（單位）改變訂單的頻率可以使訂單處理、能力和庫(kù)存之間有一定的緩沖余地安全庫(kù)存(SS)用于應(yīng)付變化（如：需求量、質(zhì)量、供應(yīng)商交付等）的零件需求57ReplenishmentPullSystemsPurchasePullSystemParameterLTisthetimetoreplenishapartfromasupplieroncetheparthasbeenconsumed.Itshouldinclude:POGeneration+SupplierLT+Transportation+Receiving/InspectionOFisthefrequencythataspecificpartisordered(drivesorderquantity)SupplierLeadTime(LT)and

OrderFrequency(OF)GenerateandMail/FaxPOReceive

andLog/EnterPOPrepareandShipProductTransportProductReceiveandInspectProductLT58ReplenishmentPullSystemsLTisthetimetoreplenishaLT是從供應(yīng)商那里補(bǔ)充零件直到該零件被消耗的時(shí)間，包括以下內(nèi)容：PO生成+供應(yīng)商LT+運(yùn)輸+接受/檢驗(yàn)OF是指某一零件的訂貨頻次（決定驅(qū)動(dòng)定貨數(shù)量的變化）供應(yīng)商交貨期(LT)和

訂單頻率(OF)產(chǎn)生和Mail/FaxPO供應(yīng)商收到并記錄/輸入PO供應(yīng)商準(zhǔn)備及發(fā)運(yùn)貨物產(chǎn)品運(yùn)輸收料和產(chǎn)品檢驗(yàn)LT59ReplenishmentPullSystemsLT是從供應(yīng)商那里補(bǔ)充零件直到該零件被消耗的時(shí)間，包括以下PartClassificationdrivesa64%reductionintransactions,with12.5%lessinventory!OrderFrequencyABCPartClassificationManytimesitisfinanciallyadvantageoustosetdifferentorderfrequenciesfordifferent“classes”ofparts.ThisisusuallyperformedviathePareto(80/20)Analysisusingstandardand/orextendedcosts:60ReplenishmentPullSystemsPartClassificationdrivesa6零件分類(lèi)法讓事務(wù)處理量被減少64%，庫(kù)存被減少12.5%訂單頻率ABC零件分類(lèi)大多數(shù)情況下，出于財(cái)務(wù)考慮/根據(jù)不同零件“分類(lèi)”設(shè)定為不同的訂貨頻次，一般采用柏拉圖（80/20）分析，其標(biāo)準(zhǔn)/附加成本：61ReplenishmentPullSystems零件分類(lèi)法讓事務(wù)處理量被減少64%，庫(kù)存被減少12.5%訂單PurchasePartSafetyStockSizingSSisafunctionof:Demandvariability()DesiredservicelevelSupplierleadtime(LT)Supplieron-timeperformance()KeyAssumption:Thedemandprofileisnormallydistributed.50%84%98%CoefficientVariation=s/xSafetyStock=*servicelevel*(MCT)where=0.762ReplenishmentPullSystemsPurchasePartSafetyStockSiz采購(gòu)件的安全庫(kù)存規(guī)模SS是以下內(nèi)容的函數(shù):需求變化()期望的服務(wù)水平供應(yīng)商交貨時(shí)間(LT)供應(yīng)商準(zhǔn)時(shí)交貨表現(xiàn)()重要假設(shè):需求的曲線呈正態(tài)分布50%84%98%變量系數(shù)=s/x安全庫(kù)存=*服務(wù)水平*(MCT)這里=0.763ReplenishmentPullSystems采購(gòu)件的安全庫(kù)存規(guī)模SS是以下內(nèi)容的函數(shù):50%84%98PurchaseLeadTimeand

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!64ReplenishmentPullSystemsPurchaseLeadTimeand

On-Time采購(gòu)交貨期和

按時(shí)交貨表現(xiàn)50%84%98%件每周(需求)安全庫(kù)存=*服務(wù)水平*(LT)舉例:三種零件有相同的變量系數(shù)(s/x=1.2),標(biāo)準(zhǔn)差為75.零件A的交貨時(shí)間是5天,零件B的交貨時(shí)間是20天,零件C的交貨時(shí)間為40天.假設(shè)期望的服務(wù)水平為98%，=0.7,那么每種零件要求的安全庫(kù)存是多少?回答:SSA=75x2x(5^.7)=462unitsSSB=75x2x(20^.7)=1221unitsSSC=75x2x(40^.7)=1984units減少交貨時(shí)間成為庫(kù)存管理策略的關(guān)鍵部分65ReplenishmentPullSystems采購(gòu)交貨期和

按時(shí)交貨表現(xiàn)50%84%98%件每周DemandVariability: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.DemandProfile66ReplenishmentPullSystemsDemandVariability:Impacton需求的可變性:對(duì)安全庫(kù)存的影響對(duì)于每項(xiàng)產(chǎn)品需要多少安全庫(kù)存？,給定98%的期望供給率？(假設(shè)對(duì)于每項(xiàng)產(chǎn)品的補(bǔ)充交貨時(shí)間為5天)ADUA=15標(biāo)準(zhǔn)差A(yù)=75SSA=____件(安全庫(kù)存計(jì)算式)____件/15件/天=___天SSADUB=10標(biāo)準(zhǔn)差B=75SSB=____件(安全庫(kù)存計(jì)算式)____件/10件/天=___天SSADUC=5標(biāo)準(zhǔn)差C=75SSC=____件(安全庫(kù)存計(jì)算式)____件/5件/天=___天SS一般的方法是對(duì)所有的產(chǎn)品項(xiàng)目盡量保持同樣的庫(kù)存.這種方法可能對(duì)某些產(chǎn)品來(lái)說(shuō)庫(kù)存太多，而對(duì)另外的產(chǎn)品又不夠。需求變化圖67ReplenishmentPullSystems需求的可變性:對(duì)安全庫(kù)存的影響對(duì)于每項(xiàng)產(chǎn)品需要多少安全庫(kù)存BasicPullFormulasfor

PurchasedPartsBOHPurchasedOrders(SumPO)SLTMaxLoop*=(LT*Dmd)+(OF*Dmd)+SSMinKanban/TriggerPoint=(LT*Dmd)+SSOrderIf:(BOH*+SumPO)<=TriggerPointOrderQty=MaxKanban–(BOH*+SumPO)OFSSLTPurchasedPartsAvgBOH* BalanceOn-Hand(BOH) MaxLoop=MaxKanbanMaxMin68ReplenishmentPullSystemsBasicPullFormulasfor

Purcha采購(gòu)零件拉系統(tǒng)的基本公式現(xiàn)存余額BOH采購(gòu)定單SLTMaxLoop*（拉系統(tǒng)環(huán)里的最大庫(kù)存）=(LT*Dmd)+(OF*Dmd)+SSMinKanban/TriggerPoint拉系統(tǒng)環(huán)里的最小庫(kù)存/觸發(fā)點(diǎn)=(LT*Dmd)+SS如果:(BOH*+SumPO)<=TriggerPoint觸發(fā)點(diǎn)時(shí)就訂貨訂單數(shù)量=MaxKanban–(BOH*+SumPO)OFSSLT采購(gòu)的零件AvgBOH* BalanceOn-Hand(BOH)策略緩沖中的庫(kù)存數(shù)量 MaxLoop=MaxKanbanMaxMin69ReplenishmentPullSystems采購(gòu)零件拉系統(tǒng)的基本公式現(xiàn)存余額采購(gòu)定單SLTMaxLooExample#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?70ReplenishmentPullSystemsExample#1:

PurchasePullSyst舉例#1:

采購(gòu)拉系統(tǒng)采購(gòu)件“11111”已知以下數(shù)據(jù):OF = 10天LT = 20天安全庫(kù)存 = 50天需求 = 2.0件/天決定最大看板數(shù)量(Kmax)MaxLoop=(OFx需求)+(LTx需求)+SS=(____x______)+(___x______)+(__)=________決定最小看板數(shù)量/觸發(fā)點(diǎn)(Kmin)MinKanban=(LTx需求)+SS=(___x______)+(__)=________有獎(jiǎng)問(wèn)答:如果BOH=50件，SumPO’s=50件,我們要補(bǔ)充嗎？如果要，補(bǔ)充多少？71ReplenishmentPullSystems舉例#1:

采購(gòu)拉系統(tǒng)采購(gòu)件“11111”已知以下數(shù)據(jù)舉例#1:

采購(gòu)拉系統(tǒng)（答案）采購(gòu)件“11111”已知以下數(shù)據(jù):OF = 10天LT = 20天安全庫(kù)存 = 50天需求 = 2.0件/天決定最大看板數(shù)量(Kmax)MaxLoop=(OFx需求)+(LTx需求)+SS=(_10_x__2__)+(_20__x__2___)+(50*2)=___160_____決定最小看板數(shù)量/觸發(fā)點(diǎn)(Kmin)MinKanban=(LTx需求)+SS=(_20_x___2__)+(50*2)=___140____有獎(jiǎng)問(wèn)答:如果BOH=50件，SumPO’s=50件,我們要補(bǔ)充嗎？50+50<140,需要補(bǔ)充160-50-50=60，72ReplenishmentPullSystems舉例#1:

采購(gòu)拉系統(tǒng)（答案）采購(gòu)件“11111”已知Usingthedataonthepreviousslide,calculate

thefollowing:WhatistheHighestBufferInventory?______WhatistheLowestBufferInventory?__