SQA Capability

©Black&Decker(U.S.),Inc.;20006sSIXSIGMABlack&DeckerSupplierQualityAssuranceSeriesMeasurementSystemAnalysisNormality-DataModelingStabilityCapabilityControl©Black&Decker(U.S.),Inc.;20006sSIXSIGMA2Step4-EstablishProcessCapabilityObjective:BaselinecurrentabilitytomeetcustomerCTQsToolsinthisStep:•VariableProductCapability•AttributeProcessCapability•Non-NormalProcessCapability•WeibullLifePlotting•CentralLimitTheorem•ConfidenceIntervals•SampleSizeSelectionElementsofthisStep:•Determineiftheproduct/servicecurrentlymeetscustomerperformancestandards.•EstablishshorttermDPMOandSigma.•Ifprocessis6sigmacapable,thenmaintainit.Goal:Establishhowwellthecurrentproduct/servicemeetsCTQ’stoday.©Black&Decker(U.S.),Inc.;20006sSIXSIGMA3VariableData-ProductCapability…..©Black&Decker(U.S.),Inc.;20006sSIXSIGMA4WhydoweneedtoAssessProductCapability?Allowsustoquantifythenatureoftheproblemwewillattackasoneofthefollowing:–Arethespecificationscorrectfortheparameter(Y)ofinterest(processorperformanceoutputvariable)?–Isthelocationofthecentraltendencyoftheparameter(Y)centeredwithintheappropriatespecifications?–Istheprocessvariationintheparametergreaterthanallowedbythespecifications?AllowstheorganizationtopredictdefectlevelsescapingtheprocessJustifiesfixingtheprocessiftheproductisnotmeetingcustomerspecifications.©Black&Decker(U.S.),Inc.;20006sSIXSIGMA5LongTermVS.ShortTermCapability-1stShiftNewOperatorDifferentMaterialShortTerm:LowerLimitUpperLimitLongTerm:SST2ndShiftSSB©Black&Decker(U.S.),Inc.;20006sSIXSIGMA6CapabilityIndices(long-termvsshort-term)(USL-LSL)Pp=6*slongtermLong-TermCapabilityIndicesZLT=3Ppk(USL-LSL)Cp(best)=6*sshorttermShort-TermCapabilityIndicesZST=3CpkMin(USL-x,x-LSL)3*sshorttermCpk=Min(USL-x,x-LSL)3*slongtermPpk=CpisprocesscapabilitypotentialCpkisprocesscapabilityPpisprocessperformancepotentialPpkisprocessperformanceWeareconcernedaboutLong-TermresultsinStep4ThinkZminhere©Black&Decker(U.S.),Inc.;20006sSIXSIGMA7ProcessStudyMethodStep1:Obtain50to100partsmanufacturedovertime.Step2:MeasureproductfeaturebasedonQCdimensions.Step3:EntervariabledataintoMinitabStep4:CalculateCpkandPpkStatQualityToolsCapabilityAnalysis(Normal)Dataarrangedinsinglecolumn.Subgroupsize:Foronlyshort-termdata---setequaltototalpartsForonlylong-termdata---setequalto1Forshort-longcombination---settosubgroupsizeEnterupperandlowerspecificationsStep5:ReadCpk,Ppk,andestimatedPPMoffchartproduced.©Black&Decker(U.S.),Inc.;20006sSIXSIGMA8ClassExampleCreaterandomdatawithameanof10andsigmaof1•CalcRandomDataNormal–Generate100rows–Mean=10–StandardDeviation=1Runnormalcapabilityanalysisondata•StatQualityToolsCapabilityanalysis(normal)151311975USLLSLProcessCapabilityAnalysisforDataPPMTotalPPMUSLPPMLSLPPMTotalPPMUSLPPMLSLPPMTotalPPMUSLPPMLSLPpkPPLPPUPpCpmCpkCPLCPUCpStDev(LT)StDev(ST)SampleNMeanLSLTargetUSL4.962.742.214.962.742.210.000.000.001.521.531.521.52*1.521.531.521.521.094621.0946210010.02475.0000*15.0000ExpectedLTPerformanceExpectedSTPerformanceObservedPerformanceOverall(LT)CapabilityPotential(ST)CapabilityProcessDataSTLTPpkPPM(DPMO)AretheseresultslongTermorShortTerm?©Black&Decker(U.S.),Inc.;20006sSIXSIGMA9WhatdotheseResultsMean?DPMOLTSigmaSTCpkST66,8073.01.0022,7503.51.176,2104.01.331,3504.51.502335.01.67325.51.833.46.02.0Cpk=Ppk+.5(basedon1.5sigmashift)PoorGoodExcellentAt6Sigma!©Black&Decker(U.S.),Inc.;20006sSIXSIGMA100.00.51.01.52.02.53.03.54.00.50.60.70.80.91.01.11.21.31.41.51.61.71.81.92.0ObservedCpActualCp0%10%20%30%40%50%%R&RAs%R&RdecreasestheCpincreasesAside:R&REffectonCapability©Black&Decker(U.S.),Inc.;20006sSIXSIGMA11Non-normalProcessCapability…..©Black&Decker(U.S.),Inc.;20006sSIXSIGMA121086420-2-4USLLSLProcessCapabilityAnalysisforC1PPMTotalPPMUSLPPMLSLPPMTotalPPMUSLPPMLSLPPMTotalPPMUSLPPMLSLPpkPPLPPUPpCpmCpkCPLCPUCpStDev(LT)StDev(ST)SampleNMeanLSLTargetUSL116383.304.70116378.60116383.304.70116378.600.000.000.000.400.401.480.94*0.400.401.480.941.778211.778211002.12190.0000*10.0000ExpectedLTPerformanceExpectedSTPerformanceObservedPerformanceOverall(LT)CapabilityPotential(ST)CapabilityProcessDataSTLTBox-CoxTransformationExampleCalcrandomdataChisquare,100rows,df=2Letsfirstgeneratenon-normaldata:Performanormalcapabilitystudyonthedata:StatQualityToolscapabilityanalysis(normal)USL=10,LSL=0PPM=116,000Whysohigh?©Black&Decker(U.S.),Inc.;20006sSIXSIGMA13TransformthedatausingBoxcoxpowertransformation.Storetransformeddatafornormalitytest(sometinesBox-Coxdoesn’tfixit).Box-CoxtransformationStatControlChartsBoxCoxTransformations..3.002.752.502.252.001.751.501.251.000.750.500.250.00-0.25111098765432195%ConfidenceIntervalStDevLambdaLastIterationInfo1.4021.4041.4140.3930.3370.281StDevLambdaUpEstLowBox-CoxPlotforC1LambdaEst=.337©Black&Decker(U.S.),Inc.;20006sSIXSIGMA142.52.01.51.00.50.0USL*LSL*ProcessCapabilityAnalysisforC1Box-CoxTransformation,WithLambda=0.337PPMTotalPPMUSLPPMLSLPPMTotalPPMUSLPPMLSLPPMTotalPPMUSLPPMLSLPpkPPLPPUPpCpmCpkCPLCPUCpStDev*(LT)StDev(LT)StDev*(ST)StDev(ST)SampleNMean*MeanLSL*LSLTargetUSL*USL8657.046657.511999.538657.046657