精益生产第4讲

精益生产第4讲LeanManufacturing/Operations7QualityToolsCG.RobinsonPsychologySystemThinkingTheoryofKnowledgeCHANGEDataCollectionRunChartsHistogramsControlChartsCause&EffectParetoScatterDiagramsRadar/GlyphChartsVariationUnderstandingVariationDisplay&UnderstandInvestigateSourcesLeanManufacturing/OperationsCG.RobinsonRecapPreviouslectureDatacollection2.RunCharts3.Histograms4.ControlCharts specialcausevariation commoncausevariation Cp&Cpk5.TeringLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonDateTotalDeliveriesSuMTWThFSSuMTWThFSSuM10/110/210/310/410/510/610/710/810/910/1010/1110/1210/1310/1410/1510/16319305284252301526499290319258276309462508327274TWTh10/1710/1810/19384145343972574938414137577543441020304050607080903411433158113042018321NumberLateXrMeanx46.9UCLx76.69LCLx17.11spreadLeanManufacturing/OperationsMeasuresProcessCapabilityThevoiceoftheprocessAprocessmustbestablebeforeitisconsideredcapableAprocesscapabilityindexisatechniqueforsummarisingthecapabilityandlocationofaprocessthatisinstatisticalcontrolNevercomputeaprocesscapabilityindexforaprocessthatisnotinstatisticalcontrolUsegraphslikecontrolchartsandhistogramstosupportanystatisticalindicesreportedCG.RobinsonLeanManufacturing/OperationsMeasuresProcessCapabilityFurtherDataCG.RobinsonThetoleranceoflatedeliveriesthebusinesscanstandisbetween44and64.(thespecification)Sotheupperspeclimitis64andthelowerspeclimitis44LeanManufacturing/OperationsMeasuresProcessCapability=ENGINEERINGSPECIFICATIONUSLLSLET==R_=1.128STANDARDDEVIATIONDATA3Sd6Sd..SdSdSd3Sd6Sdxx36=CAPABILITYINDECES(Cp)6SdETCp..PROCESSAPABILITYINDEX(Cpk)==..X_-USLDA3SdCpkupper==-..X_LSLDB3SdCpklowerCpkWARNING,ONLYCONTINUEIFPROCESSISSTABLEANDPREDICTABLECG.RobinsonLeanManufacturing/OperationsMeasuresProcessCapability=ENGINEERINGSPECIFICATIONUSLLSLET==R_=1.128STANDARDDEVIATIONDATA3Sd6Sd..SdSdSd3Sd6Sdxx36=CAPABILITYINDECES(Cp)6SdETCp..PROCESSCAPABILITYINDEX(Cpk)==..X_-USLDA3SdCpkupper==-..X_LSLDB3SdCpklowerCpkWARNING,ONLYCONTINUEIFPROCESSISSTABLEANDPREDICTABLE11.2644420206446.917.146.9442.9.098QuotethelowervalueofthetwoCG.Robinson-9.929.759.4.33659.49.9.575.09769.929.729.7LeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCpwidthoftheprocesswidthofengineeringtoleranceCG.RobinsonShortRunSPCUsingDeviationFromAimInshortrunSPC,we'remakingafewpartsofdifferentsizes,sowecan'treallyusetheactualmeasurements.Insteadofevaluatingthevariationofeachmeasurement,weusethevariationofpartsfromatargetvalue.

So,ifthefirstgroupofpartshasatargetvalueof74mm,wemeasureeachpartanddeterminethevariationfromthetarget.Ifthenextgroupofpartshasatargetvalueof60mm,wemeasurethoseanddeterminetheirvariation.Ideally,thevariationfromthetargetvaluewillremainstableeventhoughthepartsvaryinsize.LeanManufacturing/OperationsControlorProcessBehaviourChartsBarLengthMTWThF10/210/310/410/510/6-.10-.2-.1+.500.20.40.60,8DateSizer.1.2.1.6-0.2-0.4-0.6-0,8PartA2,60+/-.08Deviation2,52,62,42,53,1MTWThF10/210/310/410/510/6-.3-.2-.2-.3+.100.20.40.60,8r,10,1,4-0.2-0.4-0.6-0,8MTWThF10/210/310/410/510/61,51,91,31,31,700.20.40.60,8r,4,2,6,4-0.2-0.4-0.6-0,8PartB3,40+/-.08PartC1,50+/-.083.13,23,23.13.5+,4-,2-,2+,20LeanManufacturing/OperationsControlorProcessBehaviourChartsShortRunSPCUsingDeviationFromAimPartA=2,60+/-.08BarLengthPartB=3,40+/-.08PartC=1,50+/-.08MTWThF10/210/310/410/510/600.20.40.60,8DateSizer-0.2-0.4-0.6-0,8Deviation-.10-.2-.1+.506162,52,62,42,53,1PartAAAAA-.3-.2-.2-.3+.122023.13,23,23.13.51,51,91,31,31,73601+,4-,2-,2+,2041BCBCBCBCBCLeanManufacturing/OperationsControlorProcessBehaviourChartsShortRunSPCUsingDeviationFromAimLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonVideo“AJapaneseControlChart”WhichcontrolchartUseX-MRchartIsitVariablesData?SubGroupSize=1?UseXRchartCanthedatabeingcollectedbelargerthanthesubgroup?Equalsizedsubgroups?Equalsizedsubgroups?Usec-chartoru-chartUseu-chartUsenp-chartorp-chartUsep-chartNo(attributesdata)yesyesyesyesyesnonononoLeanManufacturing/OperationsCG.RobinsonLeanManufacturing/OperationsControlorProcessBehaviourChartsCG.RobinsonTypes&wheretousethemLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.Robinson“TheDemingmanagementMethod",MaryWalton,Pages105to107&111to116isbn1-85252-141-4“AStudyoftheToyotaProductionSystem",ShingeoShingo,Pages16to17,isbn0-915299-17-8“TheLeanToolbox",JohnBicheno,Pages174to175,ShortRunSPC, isbn0-9513-829-9-3LeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonVideo“AJapaneseControlChart”TakenotesfordiscussionafterwardsLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonLeanManufacturing/OperationsMeasuresControlorProcessBehaviourChartsCG.RobinsonLeanManufacturing/OperationsControlorProcessBehaviourChartsCG.RobinsonLeanManufacturing/OperationsCG.RobinsonLeanManufacturing/OperationsCG.RobinsonRecapPreviouslectureDatacollection2.RunCharts3.Histograms4.ControlCharts specialcausevariation commoncausevariation Cp&Cpk5.TeringLeanManufacturing/Operations7QualityToolsCG.RobinsonPsychologySystemThinkingTheoryofKnowledgeCHANGEDataCollectionRunChartsHistogramsControlChartsCause&EffectParetoScatterDiagramsRadar/GlyphChartsVariationUnderstandingVariationDisplay&UnderstandInvestigateSourcesCause&EffectCG.RobinsonLeanManufacturing/Operations7QualityToolsCause&EffectDiagramsPurpose:Togenerate,identifyandsortpotentialcausesofvariationwithinaprocessCG.RobinsonLeanManufacturing/OperationsCause&EffectDiagramsUse&Benefits:VerysimpletouseHelpssortpossiblecausesofvariationProvidesasystematicapproachtoproblemsolvingDocumentsideasandtheoriesGetsalltheexpertsinvolvedCG.RobinsonLeanManufacturing/OperationsCause&EffectDiagramsConstruction:MaterialsMethodEquipmentPeopleEnvironmentEffectCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseCauseNote:YoumayuseotherheadingsifyouwishCauseCategoriesAqualitycharacteristic,PreferablynumericCG.RobinsonLeanManufacturing/OperationsCause&EffectDiagramsMethod:CreatetheteamofexpertsYoumustdefinetheproblemclearly(MostImportant)DefinethefishbonecategoriesBrainstormeachcausecategoryandrecordallideasReviewallideasaskingwhyatleast5timestoestablishtherootcause(exle)Ranktheideasintoprimary(mostlikely)andsecondary(letskeepthemforlater)Createanactionlistfordatacollection,withownersandtimescalesCG.RobinsonLeanManufacturing/OperationsCause&EffectDiagramsFacilitationRules:EncourageSpontaneousfreewheelingresponsesDonotdiscussindividualsideasCreateasupportiveenvironmentWriteeverythingdownEncourageresponsefromthequieterparticipantsDiscouragenon-verbalresponsestoideasCG.RobinsonLeanManufacturing/OperationsCause&EffectDiagramsLimitations:Dealsonlywithopinions,thereforetheoriesmustbetestedThestructure(i.e.,mainbranchcategories)haveatendencytoleadpeoplesthinkingandmustbeidentifiedbeforehandNoteffectiveifthereisfearamongthegroupCause&Effectdiagramisonlyasgoodastheideasgenerated.ThereforefollowingbrainstormingguidelinesisveryimportantCG.RobinsonParetoCG.RobinsonLeanManufacturing/OperationsMeasuresParetoParetodiagramssummariseitemsbytheirrelativefrequencyandorganisestheminorderofdecreasingfrequency.PurposeCG.RobinsonLeanManufacturing/OperationsMeasuresParetoPareto’sLaw(alsoknownasthe80;20rule)Statesthat20%ofcausesgives80%oftheeffect,e.g.,20%ofcustomersgenerate80%ofturnover.ThisisnotarigidrulebutausefulguideCG.RobinsonLeanManufacturing/OperationsMeasuresParetoBenefitsProvidesagraphicalmethodforprioritisingissuesHelpstoseparatethevitalfewfromthetrivialmanyProvidesameansofviewingissuesfromdifferentperspectivesCanbeusedtocomparetherankorderofproblemsTocomparethenumberofproblemsbeforeandafterimprovementeffortCG.RobinsonLeanManufacturing/OperationsMeasuresParetoWhatisthebiggestreasonforbeinglateforwork?

Pareto:-TrafficJamLefthouselateCartroubleSnowstormRanerrand510DatacollectedoverathreemonthperiodCG.RobinsonLeanManufacturing/OperationsMeasuresParetoLimitationsLimitationsDoesn’tdistinguishbetweenspecialandcommoncausesUseshistoricaldatanotrealtimeOftennotactedupon(especiallyiflargestfacto