SPC基本概念介绍

SinderellaLiuSPCConceptsSinderellaLiuFundamentalSPCConceptShewhartControlChartIntroductionAverageandRangeControlChartAverageandMovingRangeControlChartWesternRulesCp/CpkIntroductionRealAppliedSinderellaLiuTIME精神產業型態1920-QI檢驗出來-檢驗員大多停留在手工製造1940–QC製造出來-統計的品管開始有生產線之形成1950-QA設計出來-品質保證大戰-需高可靠度武器1970-TQC管理出來-全面品質管制1980-TQA習慣出來-全面品質保證企業開始強調整體形象SinderellaLiuSTATISTICALPROCESSCONTROLAstructuredmathematicalmethodofanalyzingdataornumbersAsetofconditionsorcauseswhichworktogethertoproduceagivenresultTomakeaprocessbehavethewaywewantittobehaveSinderellaLiuVariousDefinitionsofSPC:•ControllingProcessesusingStatisticalTechniquesorMethods•ItistheuseofStatisticalControlChartstomonitorandcontrolmanufacturingoperationsinrealtime•ItistheuseofControlCharts&StatisticalTechniquestopreventaprocessfromgoingoutofcontrol…whichaffectstheproductyield…aswellas…quality/reliabilitylevels•Itistheeliminationofunnaturalvariancetoimprovetheprocess[SpecialCause]SinderellaLiuSPCis…amethodofusingstatisticstoidentifypatternsandtrendsinordertocontroltheprocessDataCollectionProcessStatisticalMethodAbnormalStableProcessAnalysisActionsContinuousImprovementSinderellaLiu•ImproveQuality/Yields•IncreaseProductLifeandReliability•GreaterCustomerSatisfaction•Government&CustomerRequirement•TobeMoreProfitableSinderellaLiu•ImproveQualitybyremovingthecausesofproblemsinthesystem..inevitably..leadstoimprovedproductivity•Thepersondoingthejobismostknowledgeableaboutthejob•Peoplewanttobeinvolvedanddotheirjobswell•EverypersonwantstofeellikeavaluedcontributorSinderellaLiu•Astructuredproblemsolvingprocessusingstatisticalmethodsandgraphicaltechniques…proceduresbettersolutionsthaninanunstructuredprocess•Graphicalproblemsolvingtechniquesletyouknow:•therelativeimportanceofproblemstobesolved•whetherthechangesmadehavehadthedesiredimpact•Adversarialrelationshipbetweenlabor&managementiscounterproductive&outmoded•EveryOrganizationhasundiscovered“gems”waitingtobedevelopedSinderellaLiuProductDesignProcessCustomerneedsQualityResponseNominalvalueConceptualFrameworkforSPCTheoriginsandnaturalofvariabilitySinderellaLiuConceptualFrameworkforSPCTheoriginsandnaturalofvariabilityManufacturingProcessRawMaterialToolConditionQualityResponseSinderellaLiuConceptualFrameworkforSPCTheoriginsandnaturalofvariabilityProductuseinthefieldTemperaturePowerQualityResponseSinderellaLiuConceptualFrameworkforSPCTheoriginsandnaturalofvariabilityProductuseOverTimeWearAgingQualityResponseSinderellaLiuProcessEvaluationOverTimeAccuracy&PrecisionAccuracyishowwellnumberscenteronyourtarget.Precisionishowalikethenumbersare.AccuratePreciseYesNoYesNo**********************************SinderellaLiuProcessEvaluationOverTimeAccuracy&PrecisionTargetTargetHighAccuracy&highPrecisionLowAccuracy&highPrecisionHighAccuracy&lowPrecisionLowAccuracy&lowPrecisionSinderellaLiuProcessEvaluationOverTimeTimeProcessinstatisticalcontroloneuniquecausalsystemSinderellaLiuProcessEvaluationOverTimeTimeProcessintransitioninsearchofacausalsystemSinderellaLiuProcessEvaluationOverTimeTimeProcessnotinstatisticalcontrolpopulationchangesovertimeSinderellaLiuOutputDataOutputDataOutputDataOutputDataOutputDatat1t3t4t5t2ProcessMeanUpperControlLimitLowerControlLimit☆將製程之品質特性以圖形之方式表示，把量測所得之資料點繪製於以時間為橫軸之圖形上。管制圖必須包括中心線(CenterLine)、管制界限(ControlLimit)，並應用管制規則(ControlRules)判斷之。SinderellaLiuLCLUCLCLSinderellaLiuUSLLSLUCLLCLUSLLSLUCLLCLUSLLSLUCLLCLUCLLCLInSpecificationOutofSpecificationIncontrolOutofcontrolUSLLSLSinderellaLiuAllprocessesaresubjecttotwofundamentaltypesoffaultsorproblems.Theyare:類別機遇原因(一般原因)ChanceCause(CommonCause)可歸屬原因(特殊原因)AssignableCause(SpecialCause)特性1.包括許多隨機存在之個別原因。2.任何單一機遇原因僅導致微量變異(但若許多機遇原因彙總在一起，可能產生頗大之影響)。1.包含一個或少數偶爾發生之原因。2.任何單一可歸屬原因均可造成大量之製程變異。可能原因機器之微震原料之略微差異作業員之錯誤機器不正確之設定不合格原料解說1.消除製程中之機遇變異不符合經濟原則。2.當僅有機遇變異出現時，製程處於可接受水準；倘若仍有不合格品產生，則必需進行基本製程改變或修定規格，以減少不合格品。3.當觀測值在管制界限內時，表示製程不應調整。4.當僅有機遇變異時，製程相同穩定，可以用抽樣程序預測產品品質。1.可歸屬變異可以被偵測出；消除該變異通常均合乎經濟原則。2.當有可歸屬原因出現時，製程未在可接受水準。3.當觀測值超出管制界限時，通常表示製程應予以調整和矯正。4.當有可歸屬原因出現時，製程不夠穩定，不宜以抽樣程序預測產品品質。SinderellaLiu☆DEFINITION:It’sasnapshotofyourprocessovertimeprovidingfurtherinsightastotheconsistencyandqualityofthatprocess.☆PURPOSE:AControlChartisatoolwhichallowsyoutodetermineifthe“Process”haschanged.Theupperandlowercontrollimits(whicharesetstatistically)furtherallowyoutodetermine,withadegreeofcertainty,thatthechangeisarealchange;i.e.,statisticallysignificantchange.SinderellaLiu☆ShewhartControlChartThinking:InthecontextoftheShewhartcontrolchartmethodwhatwedoiscollectanamountofdata(say,ksamplesofsizeneach)thatwethinkissufficienttoallowustotreattheaverageofallthesedataasifitweretheactualprocessmean.☆ControlChartsisintroducedtoIndustrybyWalterShewhartinthe1920’sSinderellaLiu☆計量值(VariableData/MeasurableData)種類適用狀況平均值與全距管制圖․可用以管制分組之計量數據，即每次同時取得幾組數據之工程，如長度、濃度、成份等․是掌握工程狀態最有效之管制圖平均值與標準差管制圖․與相同，用於subgroupsize≧10時中位數與全距管制圖․與相同，但檢出力較差個別值與移動全距管制圖․適用於找出不同subgroup間之變化時ChartXRChartXSChartXRChart~RXChartXRChartmRXSinderellaLiu種類適用狀況P-Chart不良率管制圖․其數據有兩種類別，如合格/不合格、通過/不通過等NP