优化生产中的物流活动

MaterialMovementinaLeanManufacturingOperation优化生产中的物流活动TotalSystemsDevelopment全体系生产提高JIT生产(准时,准量生产):Whatismeantbytheterm,“Just-In-Time”?JIT生产意味着什么?–DoesitmeanJITSupply?准时,准量供应?–DoesitmeanJITProduction?准时,准量生产?So,whatisJust-In-Time?那么,什么是准时准量生产?Theconceptofproducingthenecessaryunitsinthenecessaryquantitiesatthenecessarytimeisdescribedbytheshort-phrase“Just-In-Time”.JIT生产是:在必需时间内生产必需数量的必需部品的概念.Forexample….Inbuildingshoes:Thenecessarysubassembliesoftheproceedingprocess(uppersandbottoms)shouldarriveattheassemblylineatthetimeneededintheamountsneeded.举例说明:在生产成品鞋的时候:制鞋所必需的部件(鞋帮和鞋底)要准时,准量,准型号地到达制造车间.IfweachieveJIT:如果我们做到准时,准量生产:•Unnecessaryinventorieswillbeeliminated.不必要的库存就会消除•Storesandwarehouseswillnotbeneeded.储存区和仓库也可以取消•Materialcarryingcostswillbediminished.资材搬运成本降低However….TorelysolelyonacentralplanningapproachthatinstructstheproductionschedulestoallprocessessimultaneouslyisnotlikelytoresultinaJITprocessforalloperations.但是：单纯地依赖计划生产的方法,使所有工序同步生产，并不能完全实现所有环节的准时，准量生产.TransferWasherAssemblyMachining加工Welding焊接Assembly组装Shipping装船WeeklySchedule每周生产计划Typically,onecontroloperationreceivesthecustomers’ordersanddisseminatesschedules.通常，生产控制部门接受客户定单，然后制订并传达计划.ProductionControl生产控制TransferWasherAssemblyMachining加工Welding焊接Assembly组装Shipping装船WeeklySchedule每周生产计划ProductionControl生产控制IIIIIITheproblemcomeswhenachangeismadeeitherbecausetheorderchangesorequipmentbreaksdown.但是当定单有变化或设备出现问题的时候，就会发生一些问题：库存库存库存库存Theresultisexcessinventory…结果是导致过多的库存……withintheplantasWork-In-Process…在本车间工序内积压过多的库存…supplierssendinginpartsthatarenotneeded…上一道工序发来的并不需要的部件Additionally另外,•Weneedextrafloorspacetostorethematerial.我们需要额外的空间来堆放材料•Needexpeditorstosatisfythechangesinschedule.需要人力和时间投入来改变生产计划•Runovertimetomakeuppartsthatwenowneed.用加班时间来生产现在所需部件Toyotarethoughthowtocommunicateschedules.丰田公司对调整生产计划做了改进:•Toyotadiscoveredadifferentwaytomanagetheirschedule,丰田使用不同的方法来制订调整生产计划•Theystoppedtryingtoguesswhatthecustomerwillwant.他们并不去猜想客户的需求Instead相反..•Eachdepartmenthadinstalledasmallinventoryofeachproduct.每个车间都保持少量的库存•Downstreamprocessescometothesupplyingdepartmentsandtakewhatitneeds.下一道工序到上一道工序去取他们所需部件•Thisallowstheprocessesupstreamtosimplyreplacewhatwastaken.这样,上一工序只要补充被取走的部件即可.TheToyotaProductionSystemTPS丰田体系….•Islikelytobethemoststudiedanddiscussedoperationsprogramintheworld.是极可能被全世界研究和讨论的体系•NumerousbooksandpapershavebeenwrittenaboutTPS.出版了很多关于TPS的书籍和其它资料•ManyhavecometocharacterizeTPSas“leanproduction”orNOS.许多人认为丰田体系(TPS)实际上就代表优化生产或NOSLeanManufacturing(NOS)NOS优化生产•Regardlessofanyauthor’sopinionorrational,allagreethatthefoundationofleanmanufacturing(NOS)isthecontinualpursuittoeliminatewaste.尽管大家的观点有些不一样,但所有人都认为NOS的基础是持续不断地减少浪费•Wasteisdefinedasanythingthatconsumesresourcesortime,butdoesnotaddvaluetotheproduct.浪费是任何耗费资源或时间,但不增加产品价值的活动ExcessInventoryisWaste多余的库存是一种浪费Excessinventoryhidesproblems多余的库存会隐藏一些问题SeaofInventory大量库存LongTransportation过长运输时间VendorDelivery供应商运送Absenteeism缺勤Commun-icationProblemPoorScheduling计划不力MachineBreakdown设备停机QualityProblems质量问题LineImbalance线内不平衡LongSet-UpTime过长调整时间LackofHouse-Keeping仓储管理问题沟通问题OurgoalformaterialsmanagementinNOSNOS资材管理的目标•Theidealstateisasmoothflowofmaterialsthroughoutourownfactory理想的状态是物料在整个工厂内顺畅的流动.•Wewanttotietogetherprocessesthatareseparatedbylargephysicaldistances.使那些有一定距离而相对分离的生产流程紧密结合起来•Weneedtoimprovecommunicationinregardstomaterialmovement.在物流方面要加强各工序间的沟通ThePushSystem”推动“生产体系•Intraditionalmanufacturing,variousproductionschedulesarereleasedtoallprocesses;componentmakingandassembly.在传统的生产中,各种生产计划被传达到各个工序,部件生产和组装部门.ThePushSystem(cont.)”推动“•Thesepart-makingprocessesproducethepartsinaccordancetotheirschedulesandtransportthepartstothenextprocess.部件生产部门按照收到的计划生产并把成品部件运送到下一道工序.ThePushSystem(cont.)”推动“•Thismethodmakesitdifficulttopromptlyadapttochanges.这种方法使生产很难迅速对变化作出反应•Eachproductionschedulemustbechangedateachprocesssimultaneously.每个工序的生产计划都必需同时变化以适应同步生产ThePushSystem(cont.)”推动”TheResult导致:–Thecompanymustholdextrainventoryamongallprocesses.–公司不得不在各个工序保持额外的库存–Thiscreatesanimbalanceofstockbetweenprocesses.–各工序间的库存达不到平衡ThePullSystem“拉动”生产体系Incontrast,inaPULLSYSTEM,eachprocesswillwithdrawthepartsitneedsfromtheproceedingprocess.相反,“拉动”生产体系要求各个工序仅需从上一道工序提取自己所需要的部件.BA“production”kanban“withdrawal”kanbanProduct部件Product部件Market供应超市SupplyingProcess供应工序CustomerProcess客户工序“生产”指示板“拒收”指示板ThePullSystem(cont.)”拉动”体系Sinceonlythefinal-assemblyprocesscanaccuratelyknowthenecessarytimingandquantityofpartsrequired,theyaretheonlyonestoreceiveaschedule.因为只有制造准确地了解所需时间和部件数量,以只要制造收到生产计划即可.AssemblyStock-fit准备Stitching缝纫Assembly制造Shipping装船WeeklySchedule每周生产计划FinalAssemblyreceivesascheduleandpullsfromtheMarketPlace.StitchingandStock-fitreplenishestheMarketPlace.制造接受生产计划,并借助“供应超市”拉动生产.缝纫和准备向“供应超市”补充部件.ProductionControl生产控制ThePullSystem(cont.)”拉动”体系Withtheschedule,thefinal-assemblygoestothesupplyingdepartmentsandwithdrawswhatpartsareneeded.根据生产计划,制造到供应车间去提取所需部件.ThePullSystem(cont.)”拉动“生产Theprecedingoperationthenproducesthereplacementsofthepartswithdrawnbythesubsequentprocess.这样,前一道工序开始生产被下一道工序提走的部件以补充所需.BAssembly制造Stitching缝纫A“production”