精益六西格玛在服务备件库存管理中的应用

IDMAICL()2.5421%123DMAICLDMAICLABSTRACTIITheApplicationofLeanSix-sigmaInServiceSparePartsInventoryManagementABSTRACTAfter-salesservicehasbecomearichresourceofprofit,andtimelyresponseforservicesparepartsrequirementissupposedtobeanveryimportantfactortopromisesatisfactoryafter-saleservicetocustomers.Duetouncertaintyandnon-predictability,thesparepartsinventoryandleadtimemanagementbecomerelativelydifficult,requiringabalancebetweenimprovingservicequalityandreducinginventorycost.ThispaperintroducedLeansix-sigmaandapplieditonaprojectofsparepartsinventoryimprovementforAirCompressorsinIngersollRand.ItprovesthatLeansix-sigmaisfeasibleandefficienttosolveourproblem.Leansix-sigmaintegratesmethodologyofleanthinkingandsix-sigmatogether,andutilizeDMAICL(Define-Measure-Analyse-Improve-Control-Leverage)toidentifynonvalue-addedactivitiesinbusinessprocessinordertocopewithchangingcustomerneedsandimprovingtheserviceresponse.Leansix-sigmaconnectsvalueidentifyinganddataanalysistogether.Inthispaper,itisusedtofocusoninventoryturnoverandleadtimetomeetcustomerneeds.Inthestageofimprovement,safetystockissetbasedonservicelevelThecompanyintendtoachieveThepracticalresultisthatinventoryturnoverincreasedfrom2.5to4,andpurchasingorderfulfillmentleadtimeisalsoreducedby21%,showcasingfeasibilityandeffectivenessinsolvingthiskindofproblems.Characteristicsandinnovativenesspresentedare:1)AccordingtoLeansix-sigmatheory,servicesparepartsinventorymanagementanddeliveryarebothprocesses,includingbothvalue-addedandnnvalue-addedparts.Takeinventoryturnoverandleadtimeintoaccount,thispaperhasachievedfruitfulresults;2)AttheimprovestageofLeansix-sigmaprojects,thispaperABSTRACTIIIhasgaveaproposaltosetsafetystockbasedonservicelevelanddemandforecast.Andwiththat,demanduncertaintycanbesatisfiedandinventorycosthasbeenreducedbyalargepercent;3)ApracticalcaseofInventorymanagementforservicesparepartsinAirCompressorsinIngersollRandiselaborated.ItmadeaclearpresentationofDMAICLandpinpointwherearethegeneralityandparticularityofLean-sigma.Finally,theresearchoutlookhasbeenreasonablymade.Keywords:ServicePartsInventoryManagement,LeanSix-sigma,InventoryTurnover,Leadtime,SafetyStock,DMAICL1[1]1.1[2]20%40%20%-30%20%20062.557.5%220073273%[1][2][3]1.2[3]31-11Figure1CompleteStructureofpaper42007[1]DMAICLMFG/Pro52.1[4]1),[3],KoopmanKimball[3][2][3]6RitchieRitchie,[4][3]2)[1]Hans-ChristianPfohlLeonardFortuinRuudH.Teunter[1]3)Flint1995450[5]2000BayesianKamath(2002)BayesianCroston(1972)EaveslCroston(2004)[3]Willemain(2004)BootstrapBootstrapCroston[4]Regattieria(2005)20Croston4)MaterialRequirementsPlanningMRPJustinTimeJIT7[5][3]2006SPC22.2GE70108/80DPMO50%30%9/[6][7]1+12[11][8]103.13.1.140(Lean)JIT[9]1)112)3)MudaMudaMuda4)Kanban/()()(JIT)TPM()SMED()(Workplaceorganization)5S[10]123.1.2[5](SixSigma)MotorolaGE(Define)(Measure)(Analyze)(Improve)(Control)[6]2080MotorolaBobgalvin99.9997%3.4[7]N,USLLSLu3Cp2.01.03-13.410-62Figure2Six-sigmaexpressionintermsofstatisticsD()M()A()I()C()D()M()A()D()V()I()D()O()V()13QFD()FMEA()SPC()MSA()ANOVE()DOE()MINITAB[11]1)SIPOC2)PDCADMAICSIPOC3)3.410-64)5)[12]143.23.2.1=+=-50[13]1)DMAICL2)153)DMAICL4)[6]1)2)3)4)5)6)7)3.2.2116ChampionSponsorBBGB23[5].173Figure3Differentfocusesofleanthinkingandsix-sigmaJIT[8]11/22l/22/331/1041/251/467DMAICLDMAICLDMAICL18[9]3.33.3.11)Diiiiii2)Mivv()vivii3)Aviiiix4)Ixxi5)Cxiixiii19xiv6)Lxv.4Figure4Toolsusedindifferentstagesinleansix-sigma1)2)3)204)5)(Champion)(ProcessOwner)Mentor6)217)8)DMAICL9)10)3.3.2DMAICL1.FMEA2.223.CTQ()1)2)(FortWayne)GrahamRichard2001Richard10FortWayne19%23%171703)——808550234)20061520PACU40%24[14][15]PASDMAICL20062.54PAS21%200K5255Figure5Structureofthecontent4.1[4]6Figure6Affectingfactorsoncostofspareparts264.1.1[5]20%40%[14]1)2)3)27[16]1)aa2)bb3)4.1.2209028[17][14](fr)(CSL)CSL[5](EOQ)[8]X~(,)RXNRδLLSRLS29lRRL=Lδ=RLδlRRL=222RLLLSRδδ=+()xf()xFROPssROPR−L=CSL{}CSLPLROPFδ=≤=LLROP,R,1()sLssFCSLδ−=…………..….………..….(4.1)1()sRssFCSLLδ−=…………..….………..….(4.2)12222()sRLssFCSLLSRδ−=+…………..….…..….(4.3)SSKδLRRδLδ[8]4.24.2.1[14]30[8][15]1)DMAICL2)3)4)JIT31JITJITJIT4.2.21[8]321*******************************DMAICL(VSM)(VOC)(CTQ)/33,champion)/(processowner)/DMAICLeverage345.15.1.1[18][19]123355.1.22006PAS2.557.5%OSMI[20]1)2)3)PAS4)123456365)[10]MFG/Pro[14]5.25.2.1375.2.2382FMEAkaizen2006PAS2.557.5%OSMI20073273%2006120073200710PASPAS2.532PAS2.54322539VOCVoiceOfCustomerPASPASIRMMFG/ProVOCCTQ425VOC3Y1Y2MFG/ProIRMPASIRM20062006200713MFG/ProITIRMPASChina2006120073[10]40tFFit=F/Fi…………..….………..….(5.1)421'121tttta++=……………………………..(5.2)at121'12,,tttMINITAB5-15-22.50.586Figure6summaryofinventoryturnoverrate6I2.540.3417Figure7IndividualObservationChartofinventoryturnoverrate200713MINITAB5-38Figure8Summaryofpartsleadtime42324025205.2.3,[11]1)i.ii.2)198019803)20[10]43i.ii.iii.1)123957.7%20.2%23122.2%44Count437332168979153793Percent57.522.220.2Cum%57.579.8100.0CountPercentInventoryStructureSafetyStockSOAllocatedInventoryExcessInventory8000007000006000005000004000003000002000001000000100806040200ParetoChartofInventoryStructure9Figure9ParetoChartand