统计过程控制-测量系统分析

SPCStatisticProcessControlStatistictechniqueProcessControlSPC由ProductSpec到ProcessParameter由ProductSpec到ProcessParameter1.BasicconceptofSPCVariationControl(Stability)-Statisticalstablestatus-ProcessperformancecanbepredictableCapabilityOver-adjustmentSPC-品管七大手法HistogramCheckSheetParetoCauseandeffectdiagramDefectconcentrationdiagramScatterdiagramControlchartBasicconceptofSPC检定是否为常态分配管制图的中心线X-bar管制图的管制界限(信赖水平,信赖区间)ControlLimits=信赖区间

1.集中趋势（通常以Xbar作代表）

2.离中趋势（通常以σ

作代表）

3.信赖水平-被含盖在特定范围内的机率

信赖水平-被含盖在特定范围内的机率XbarXbar

信赖水平,信赖区间

信赖水平

信赖区间

90%

±1.645σ

95%

±1.96σ

99%

±2.575σ

99.73%

±3σ

99.94%±3.5σ99.99%±3.9σ

99.994%±3.99σ信赖水平,信赖区间,P,Ppk/Cpk信赖水平P信赖区间Ppk/Cpk90%10%±1.645σ0.54895%5%±1.96σ0.65399%1%±2.575σ

0.85899.73%0.27%

±3σ

199.94%0.06%±3.5σ1.16799.99%100ppm±3.9σ1.399.994%60ppm±3.99σ1.33

ZBasicconceptofSPC用管制图判别specialcause的准则超过管制界限连续七点向上连续七点向下连续七点向单边不随机分布BasicconceptofSPCStatisticalstable=nospecialcause=Undercontrol=processperformancecanbepredictable当制程达到Statisticalstable时才可计算CpkStableProcessUnstableProcessBasicconceptofSPCOver-adjustment:当对commoncause所造成的变异都采取措施调整制程时,等于将一个specialcause加入己稳定的制程。使原本稳定的制程变成不稳定。BasicconceptofSPCPpkCaCpCpkBasicconceptofSPCCa:SensitivetoSpecificationtargetCp:Sensitivetovariation(spread)Cpk:Sensitivetoboth,capabilityindexforstableprocessOnlycommoncausevariationincludedPpk:PerformanceindexBothcommoncauseandspecialcausevariationincludedCp≦CpkBasicconceptofSPCVariation:制程输出不可避免的差异InherentVariation(固有变异):由commoncause所造成的变异σ=Rbar/d2TotalVariation:由commoncauseandspecialcause所造成的变异PpkCpkCpm

管制图种类包括计量值管制图计数值管制图Data的种类计量值(location&spread)计数值计量值管制图X-BarRChartX-medianRChartX-BarSChartX-RmChart计数值管制图种类包括

PPnCU

管制图的目的预防不良品产出判定制程是否有非机遇因子造成的变异去除非机遇因子造成的变异减小制程的变异改善制程判定制程是否稳定制程能力分析100%检验还需耍做管制图吗?如何做?特殊应用管制图CUSUMcumulative-SumControlChart)累积和管制图EWMAexponentiallyWeightedMovingAverageControlChart)指数加权移勋平均管制图EVOP(EvolutionaryOperation)-PartAverageTest渐进操作法管制图AcceptanceControlChart允收管制图ModifiedControlLimitsControlChart修正界限管制图ShortRun短制程管制图

ShortRun短制程管制图

GuardBandLimit-GRRGuardBandLimit-Cpk

MSAMeasurementSystemAnalysisStatistictechniqueMSControlMSA

MSA

GRRv.s.CPAccuracy&Precision

MSA计量值

Location-Bias,Linearity,StabilitySpread–Repeatability,Reproducibility(GRR)

RangeMethodAverageRangeMethodAverageRangeMethod(WithinPartVariation)ANOVADOE计数值-ShortMethod-LongMethodBiasStabilityLinearityRepeatabilityReproducibility

GRR-Average-RangeMethod%GRR=%R&R=100(R&R/TV)TV2=R&R2+PV2R&R2

=EV2+AV2

TV2EV2AV2PV2GRR-RangeMethodGRR-Average-RangeMethodANOVAMethodMSAtiming&applicationMSA/APQP/ProductRealizationMSA/FMEA

MSA的目的何种情况可不必做GRR?Cpisgood,notuseforprocessmeasurement,C/Inotrequired?只做GRR,不做Bias,Linearity,Stability可以吗?MSAformeasurementcan’tberepeatedTheinabilitytotestthesameunitrepeatedlyisamajorobstacletoobtaininganestimateofpuremeasurementerror.DestructivetestingMeasuringatemperature,viscositySamplesobtainedfromtheproductstreamshouldbeasclosedtogetheraspossibleWithfilm,onemightpreferadjacentsamplescollectedinthemachinedirectionratherthanfromdifferentpositionsacrossthewebObtainpairsofsamplesthatareashomogeneousaspossiblewithineachpair,eachpairmaybetestedandthedifferenceinthepairedreadingstakentoobtainanestimateofthevariationofthemeasurementprocessDataCategories&ResolutionDataCategories&ResolutionDataCategories&ResolutionDataCategories&ResolutionDataCategories&ResolutionDataCategories&ResolutionDataCategories&ResolutionDataCategories&ResolutionPTRatioPrecisionToleranceRatioTheratioofparametertolerancetomeasurementsystemrepeatabilityPT=Tolerance/EV

MSAResultGageresolutiontospectoleranceGageresolutiontoProcessvariationBiasStabilityLinearityR&RWhenshouldMSAbeconductedinAPQP/ProductRealization/ProductLifecycleProductdesignreviewProcessdes