spc统计制程管制培训教案(ppt 97页).ppt

本资料来源 2 StatisticalProcessControl統計製程管制 3 ChapterOutline概述 StatisticalThinkingandStatisticalMethods統計思維與統計方法StatisticalProcessControl SPC 統計製程管制Typesofdata資料型態Constructingcontrolcharts如何架構管制圖Interpretingcontrolcharts管制圖之說明Processcapability製程能力Acceptancesampling允收水準Inspectionprocess檢驗程序Qualitymeasures品質的量測Samplingvs screening抽樣與篩選 4 Process製程 Variation變異 Data資料 StatisticalTools統計方法 StatisticalThinking統計思維 StatisticalMethods統計方法 StatisticalThinkingandStatisticalMethods統計思維與統計方法 5 StatisticalThinking統計思維 KeyConcepts主要觀念Processandsystemsthinking製程與系統的思維Variation變異Analysisincreasesknowledge分析可以增加知識Takingaction可以採取行動Improvement可以用來改善RoleofData資料的角色Quantifyvariation量化的變異 變動 Measureeffects量測的效應 6 Youcan timproveaprocessthatyoudon tunderstand 你若對製程不懂 就無法改善製程 WithoutaProcessView若無製程的觀點 Peoplehaveproblemsunderstandingtheproblemandtheirroleinitssolution turf 吾人在其問題的理解與對策執行的角色扮演上會有問題Itisdifficulttodefinethescopeoftheproblem 難以定義問題範圍Itisdifficulttogettorootcauses 難以找到真正的要因Peoplegetblamedwhentheprocessistheproblem 80 20Rule 吾人在當製程是真正問題時 會遭到責備Processmanagementisineffective製程管理沒有效果Improvementisslowed改善緩慢 7 WithoutUnderstandingVariation若不了解其變異 Managementbythelastdatapoint永遠是用最後的資料作管理 永遠在頭痛醫頭 腳痛一腳 沒有源頭置根本的觀念 There slotsoffirefighting火災不斷Usingspecialcausemethodstosolvecommoncauseproblems用特別的方法處理共同要因的 一般性 問題Tamperingandmicromanagingabound修改與小事的管理老是存在Goalsandmethodstoattainthemfail目標與方法無法達成Understandingtheprocessishandicapped只知道製程是個問題Learningisslowed學習慢Processmanagementisineffective製程管理沒有效果Improvementisslowed改善慢 8 WithoutData若是手上沒有資料 Everyoneisanexpert 每個人都是專家Discussionsproducemoreheatthanlight討論不斷Historicalmemoryispoor歷史的記憶模糊Difficulttogetagreementon 難以得到協議若Whattheproblemis無法得知問題是什麼Whatsuccesslookslike無法得知其成果將如何Progressmade或由哪一製程所產出Processmanagementisineffective製程管理是無效的Improvementisslowed改善慢 9 Earlyon wefailedtofocusadequatelyoncoreworkprocessesandstatistics 初期若核心工作製程與統計無法適當集中 其結果 WithoutStatisticalThinking若無製程統計的思維 Yourmanagementandimprovementprocessesarehandicapped吾人的管理與改善將有障礙It slike其像Footballwithoutapassingattack足球未經核准即攻擊Growingalawnwithoutfertilizer草地未經施肥Doingresearchwithoutmeasurements研究未做量測資料Playinggolfwithoutyourirons不用自己的球竿打高爾書球 10 SECURESTORE KIT LoadProgramLoadPick PlaceLoadReflowProfileLoadStencil ScreenSolderPaste PartsSMTPlacement I RReFlow Clean PEMParts ASIC ADC DAC Placement HandSolder Clean SecondLevelAssy Touch upsolderjointsMechanicalInstallationsStaking Bonding Clean ElectricalFunctionalTest Clean Bake ConformalCoat PostTestInspection AcceptanceTestElectrical ControlledStorage InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint Through holeandPlasticPartsPreparationTinComponentsForm CutAxialLeads Through holeComponentPlacement HandSolder Clean InspectionCheckpoint PWBPreparation CleanInkStampBake ProductionOperation InspectionOperation TestOperation MaterialControlOperation KEY ManufacturingFlowDiagramofPWBAssemblyPWB組裝之製造流程圖 11 SECURESTORE KIT LoadProgramLoadPick PlaceLoadReflowProfileLoadStencil ScreenSolderPaste PartsSMTPlacement I RReFlow Clean PEMParts ASIC ADC DAC Placement HandSolder Clean SecondLevelAssy Touch upsolderjointsMechanicalInstallationsStaking Bonding Clean ElectricalFunctionalTest Clean Bake ConformalCoat PostTestInspection AcceptanceTestElectrical ControlledStorage InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint InspectionCheckpoint Through holeandPlasticPartsPreparationTinComponentsForm CutAxialLeads Through holeComponentPlacement HandSolder Clean InspectionCheckpoint PWBPreparation CleanInkStampBake ProductionOperation InspectionOperation TestOperation MaterialControlOperation KEY ManufacturingFlowDiagramofPWBAssemblyPWB組裝之製造流程圖 12 Dependsonlevelsofactivityandjobresponsibility 依據活動的層級與工作執掌 Wherewe reheaded我們朝何方 Managerialprocessestoguideus用管理的程序來指導我們 WheretheworkgetsDone讓所需的工作被執行完成 Strategic策略上的 Managerial管理上的 Operational作業性的 Executives高階決策層 Managers經理階層 Workers現場員工 UseofStatisticalThinking運用統計思維 13 Executivesusesystemsapproach 決策者運用系統導向策略Coreprocesseshavebeenflowcharted主要程序已被流程圖表化Strategicdirectiondefinedanddeployed 策略方向的訂定與展開Measurementsystemsinplace 適當的量測系統Employee customer andbenchmarkingstudiesareusedtodriveimprovement 是以員工 客戶與benchmarking的研究被用來主導改善Experimentationisencouraged 鼓勵實驗 StatisticalThinkingattheStrategicLevel決策者之統計思維 14 Managersusemeetingmanagementtechniques經理利用會議管理技巧Standardizedprojectmanagementsystemsareinplace 適當的標準化專案管理系統Bothprojectprocessandresultsarereviewed 此專案的流程與結果已被審核Processvariationisconsideredwhensettinggoals 當設定目標時 流程的變異已被考慮Measurementisviewedasaprocess 量測點被視為一個流程Thenumberofsuppliersisreduced供應者數目減少Avarietyofcommunicationmediaareused 廣泛的傳訊媒體被採用 StatisticalThinkingattheManagerialLevel經理階層統計思維 15 Workprocessesareflowcharted documented工作程序已被流程圖表化與書面化Keymeasurementsareidentified 主要量測點已被確認Timeplotsdisplayed時間的圖示被展現Processmanagementandimprovementutilize 製程管理與改善採用Knowledgeofvariation and變異觀念的知識及Dataanalysis資料分析Improvementactivitiesfocusontheprocess notblamingemployees 改善工具著重於製程 而非責備員工 StatisticalThinkingattheOperationalLevel現場員工的統計思維範例 16 StatisticalThinkingattheOperationalLevel現場員工的統計思維範例 ARecentExperience最近的經驗Hugequantitiesofdata大量的資料Limitedunderstandingofstructure在有限度理解的結構上Consultantsappliedartificialneuralnets顧問群運用人工神經網狀系統Didn twork但不成功 17 StatisticalThinkingattheOperationalLevel現場員工的統計思維範例 ARecentExperience最近的經驗ArtificialNeuralNetsapplynicelyinmanysituations NISTExamples 人工神經網狀系統出色地運用於許多領域 OpticalCharacterRecognition光學文字辨識系統FingerPrinting指紋辨識FacePrintingfortheFBI相貌辨識Example等案例上 18 But 但 Unlessyousampletheprocesstakingtherightamountoftherightkindofdata rationalsubgroups youwillneverapproachprocessunderstanding 在抽驗的流 製 程裡若你無法取得正確的數量與資料 合理的樣組 你將無法深入了解此一流 製 程Withoutprocessunderstanding thereisnoprocesscontrol 流 製 程若不了解 就無所謂的流 製 程管制 19 KeyLearningsfromStatisticalThinkingEfforts由統計思維的努力中 吾人學到的要點 Statisticiansdon tunderstandStatisticalThinkingaswellastheythinktheydo 統計的思維不僅要懂而且也要會做Thosewhodounderstandithavelimitedaccesstomanagerialandstrategiclevels 真正了解統計思維的人 在管理與決策上之能力較少受限制There smuchmoreworktobedone 較多的事能被完成Spreadtheword口令的展開Focusonprocess著重製程 QualityCharacteristics品質特性 Variables計量值Characteristicsthatyoumeasure e g weight length其特性可被量測而得 如重量 長度等Maybeinwholeorinfractionalnumbers可以以整數或分數表達Continuousrandomvariables連續的隨機變數 Attributes計數值Characteristicsforwhichyoufocusondefects其特性著重於缺點Classifyproductsaseither good or bad orcount defects以產品的好 壞 缺點數量來看e g radioworksornot如收音機是否可以播放Categoricalordiscreterandomvariables屬不連續的雖機變數 21 TypesOfData資料型態 Attributedata計數資料Productcharacteristicevaluatedwithadiscretechoice產品資料特性以離散的評估方式選定Good bad yes no良品 不良品 好 壞Variabledata計量資料Productcharacteristicthatcanbemeasured產品特性能被量測而得Length size weight height time velocity長度 大小 重量 高度 時間 速度 TypesofVariations變異型態 CommonCause共同原因Random隨機Chronic長期的Small影響小Systemproblems系統問題Mgtcontrollable管理上的控制Processimprovement製程改善Processcapability製程能力 SpecialCause特殊原因Situational局部Sporadic偶而發生Large影響大Localproblems局部問題Locallycontrollable可局部控制Processcontrol製程管制Processstability製程的穩定性 StatisticalProcessControl統計製程管制 Statisticaltechniqueusedtoensureprocessismakingproducttostandard統計技術用於確保製程所製出的產品合乎標準Allprocessaresubjecttovariability所有製程受變異性所支配NaturalorCommoncauses自然或共同原因 Randomvariations隨機變異如設備損耗Assignablecauses特殊原因 Correctableproblems可改善的問題Machinewear unskilledworkers poormaterial如生手 材料不良 Objective Identifyassignablecauses目標 確認特殊原因Usesprocesscontrolcharts利用管制圖表 24 CausesofVariation變異的原因 Inherenttoprocess固有製程Random隨機Cannotbecontrolled不可控Cannotbeprevented無法預防Examples如 Weather氣候accuracyofmeasurements量測精度capabilityofmachine設備能力 Exogenoustoprocess外來因子影響製程Notrandom非隨機Controllable可控Preventable可預防Examples如toolwear工具磨耗 Monday effect週一效應poormaintenance維護差 CommonCauses共同原因 AssignableCauses特殊原因 Whatpreventsperfection Processvariation 何事阻礙完美 製程變異 ProductSpecificationandProcessVariation產品規格與品變異 Productspecification產品規格desiredrangeofproductattribute產品屬性之期望範圍partofproductdesign產品設計的一部份length weight thickness color 長度 重量 厚度 顏色 等nominalspecification 公稱規格 upperandlowerspecificationlimits 規格上下限 Processvariability製程變異inherentvariationinprocesses製程中固有的變異limitswhatcanactuallybeachieved其實際能被達成之界限值definesandlimitsprocesscapability定義並限制製程能力Processmaynotbecapableofmeetingspecification 製程是有可能無法達到規格的要求 26 Grams a Location Average 平均值 CommonCauses共同原因 27 a Location Grams Average AssignableCauses特殊原因 28 Standarddeviation 標準差 TheNormalDistribution常態分配 29 Mean平均值 CentralLimitTheorem Standarddeviation樣本標準差 TheoreticalBasisofControlCharts 30 UCL管制規格上限 Nominal中心線 LCL管制規格下限 123Samples ControlCharts管制圖 31 123Samples ControlCharts管制圖 32 Assignablecauseslikely可能的特殊原因 123Samples ControlCharts管制圖 33 ProcessControl ThreeTypesofProcessOutputs製程管制的三種顯示型態 34 TheRelationshipBetweenPopulationandSamplingDistributions群體與樣本間之關係 35 VisualizingChanceCauses機遇原因之觀察 Target Atafixedpointintime固定時間 Time Target Overtime連續時間 Thinkofamanufacturingprocessproducingdistinctpartswithmeasurablecharacteristics Thesemeasurementsvarybecauseofmaterials machines operators etc Thesesourcesmakeupchancecausesofvariation 製造各零件之量測特性會因4M等機遇原因而發生變異 36 ProcessControlCharts製程管制圖 37 ControlChartTypes管制圖型態 計量 計數 38 ControlChartSelection管制圖的選定 QualityCharacteristic variable attribute n 1 n 10orcomputer xandMR no yes xands xandR no yes defective defect constantsamplesize p chartwithvariablesamplesize no pornp yes constantsamplingunit cu yes no 39 ProduceGood ProvideService StopProcess Yes No Assign Causes TakeSample InspectSample FindOutWhy Create ControlChart Start StatisticalProcessControlSteps統計製程管制控制步驟 40 StatisticalThinkingisaphilosophyoflearningandActionbasedonthefollowingfundamentalprinciples 統計思維哲學之學習與行動基於以下原則 Allworkoccursinasystemofinterconnectedprocesses Variationexistsinallprocesses andUnderstandingandreducingvariationarekeystosuccess 所有工作的產生源於系統互相連結之製程 而變異存在於所有製程 了解並降低製程的變異是成功的關鍵 41 UsingControlCharts如何使用管制圖 1 Selecttheprocesstobecharted選擇需要被圖表化之製程2 Get20 25groupsofsamples選擇樣組及樣本大小 usually5 20pergroupforXandR chartorn 50forp chart 3 ConstructtheControlChart建立管制圖4 Analyzethedatarelativetothecontrollimits Pointsoutsideofthelimitsshouldbeexplained分析關聯於管制界線之資料 點超出界限需能被解釋5 Oncetheyareexplained eliminatethemfromthedataandrecalculatethecontrolchart一旦澄清 消除異常點及原因 並重算管制圖資料6 Usethechartfornewdata butDONOTrecalculatethecontrollimits利用此新資料 但無須重算管制界限 XChart平均值管制圖 Typeofvariablescontrolchart計量管制圖Intervalorratioscalednumericaldata間距或比率量測數字資料Showssamplemeansovertime算出樣本平均值Monitorsprocessaverage間控製程平均數Example Measure5samplesofsolderpastePlot如計算錫膏厚度之平均值 再點圖 43 BasicProbabilitiesConcerningtheDistributionofSampleMeans有關樣本平均數之機率分佈 Std dev ofthesamplemeans樣本平均數標準差 44 EstimationofMeanandStd Dev oftheUnderlyingProcess在製程控制之下之平均值與標準差估計 usehistoricaldatatakenfromtheprocesswhenitwas known tobeincontrol當製程穩定時 利用過去所產生之歷史資料usuallydataisintheformofsamples preferablywithfixedsamplesize takenatregularintervals樣本資料是在一定間隔的時間裡取得processmeanmestimatedastheaverageofthesamplemeans thegrandmeanornominalvalue 假設製程平均值m與樣本平均值相同processstandarddeviationsestimatedby 製程標準差s估算由standarddeviationofallindividualsamples所有個別值樣本之標準差ORmeanofsamplerangeR d2 where或樣本平均值 d2samplerangeR Rmax Rmin d2 valuefromlook uptable 全距為R d2可由查表得知 45 X barvs Rcharts平均值VS全距管制圖 Rchartsmonitorvariability Isthevariabilityoftheprocessstableovertime Dotheitemscomefromonedistribution R管制圖監控變異性 是否整個製程處於安定狀態 有項目超出此一分配嗎 X barchartsmonitorcentering oncetheRchartisincontrol Isthemeanstableovertime X Bar管制圖監控中心 一旦R管制圖處於管制狀態 平均值於爭個製程是否穩定 BringtheR chartundercontrol thenlookatthex barchart 先看R圖 再看Xbar圖 46 HowtoConstructaControlChart如何建立管制圖 1 Takesamplesandmeasurethem 取樣量測2 Foreachsubgroup calculatethesampleaverageandrange 每個群組 計算平均值與全距3 Settrialcenterlineandcontrollimits 製作解析用管制圖之中心線與管制界限4 PlottheRchart Removeout of controlpointsandrevisecontrollimits 畫R圖 移除異常點 再修正管制界限5 Plotx barchart Removeout of controlpointsandrevisecontrollimits 畫R圖 移除異常點 再修正管制界限6 Implement sampleandplotpointsatstandardintervals Monitorthechart 管制用管制圖 於標準間隔時間取樣 監控此管制圖 47 Type1andType2Error第一種與第二種錯誤 Alarm NoAlarm In Control管制內 Out of Control失控 48 CommonTeststoDetermineiftheProcessisOutofControl管制圖異常之判定 Onepointoutsideofeithercontrollimit一點超出管制界線2outof3pointsbeyondUCL 2sigma3點有2點在2個標準差或以外7successivepointsonsamesideofthecentralline連續7點在中心線之同一側of11successivepoints atleast10onthesamesideofthecentralline連續11點有10點在中心線之同一側of20successivepoints atleast16onthesamesideofthecentralline連續20點有16點在中心線之同一側 49 Type1ErrorsfortheseTests第一種錯誤 TestProbabilityType1Error 2 3 7 7 10 11 16 20 1 1 2 0 00135 0 0027 0 0052 0 5 7 0 0078 0 00586 0 0059 50 Type2Error第二種錯誤 Supposem1 mType2Error whereF z denotesthethecumulativeprobabilityofastandardnormalvariateatzPower 1 Type2Error Powerincreasesas nincreases as m1 m increases andassdecreases Extensiontom1 misstraightforward 51 XChartControlLimits SampleRangeatTimei Samples SampleMeanatTimei FromTable 52 FactorsforComputingControlChartLimits管制圖之係數表 Table RChart全距管制圖 Typeofvariablescontrolchart計量管制圖Intervalorratioscalednumericaldata間距或比率量測數字資料ShowssamplerangesovertimeDifferencebetweensmallestPlot計算全距並點圖 54 SampleRangeatTimei某時間間隔之全距 Samplessize樣本大小 FromTable查表 RChartControlLimitsR管制圖管制界限公式 SettingupaX BARRChart建立X barR管制圖 Takeabout20 25samplegroups n oftheprocessresult Eachsampleshouldcontain4or5observations Foreachsamplecalculatetheaverageandtherange Averageallthesampleaverages X BAR Averageallthesampleranges R BAR Calculatetheupper lowercontrollimitforX BARCalculatetheupper lowercontrollimitforR BAR Usingans ChartInsteadofanR Chart利用標準差圖取代R管制圖 S Chartsareusedwhen Tightcontrolofprocessvariationisessential Samplesizeequals10ormore acomputercanbeusedtosimplify speedupcalculations Formulas ControlLimitsfors Chart ControlLimitsforX barChart 57 Example Thefirst20dayssamplesareasfollows 58 UCL LCL X barChart Istheprocessincontrol Arethespecificationsbeingmet Howcanwetellifthevariabilityisincontrol 59 R Chart TheRchartmeasuresthechangeinthespreadovertime PlotR therangeforeachsample LowerControlLimit UpperControlLimit UCL LCL 60 Ex Control Commutingtimes 61 Control Commutingtimes cont step4 Commutingtimes A M 62 Figure pChart不良率管制圖 Typeofattributescontrolchart計數管制圖Nominallyscaledcategoricaldata以絕對資料分類e g good bad如好 壞Shows ofnonconformingitems顯示不合格項目 Example Count defectivechairsPlot計算椅子的不良數除以椅子總檢驗數 點圖Chairiseitherdefectiveornotdefective椅子只有好與壞兩種 SettingupapChart建立p管制圖 Takeabout20 25samplesoftheprocessresult EachsampleshouldbelargeenoughtocontainATLEAST1badobservation OftenforP Chartssamplessizesareinexcessof100 Foreachsamplecalculatethepercentageofbadunits Averageallthesamplepercentagestogether thisisP BAR Calculatetheupper lowercontrollimitfortheP BARchartusingthefollowingformulas 65 pChartControlLimits不良率管制圖管制界限 DefectiveItemsinSamplei Sizeofsamplei Ifindividualsamplesarewithin25 oftheaveragesamplesizethencontrollimitscanbecalculatedusingtheaveragesamplesize z 2for95 5 limits z 3for99 7 limits Ifsamplesizesvarybymorethan25 oftheaveragesamplesizethencontrollimitsshouldbecomputedforeachsample 66 Example p Chart M MMarswantstoinstituteastatisticalprocesscontrolonanewcandybar Inordertodoso everyshifttheysample50barsanddeterminethenumberofdefectiveones Theyobtainthefollowingdata 67 20groupsof50 1000samplesTotaldefective 170p bar 0 17UCL 0 17 3x0 053 0 329LCL 0 17 3x0 053 0 010Plottingthe defectiveshows 68 IdentifyingSpecialCauses確認特殊要因 Itappearsthatshifts4 7and12wereoutofcontrol Uponfurtherinspectionitappearsthattoomuchwaterwasaddedtotheprocessinshifts4and7andthatinshift12anewoperatorstarted Sinceeachoftheoutofcontrolpointshaveassignablecauses weeliminatethemfromthedata Thenewcontrolchartisthen 69 Nowitappearsthatshift15isout of control Furthercheckingshowsthatthetemperaturewassettoohighduringthisshift Therefore wewanttoeliminatethispointsothatinsubsequenttestswecanidentifywhenthisoccurs Ifweeliminatethispointthenewcontrolchartis IdentifyingSpecialCauses 70 FinalpChart UCL 0 122 3x0 046 0 260LCL 0 122 3x0 046 0 016 0 0 negativecontrollimitsshouldbesetto0 Nowtheyshouldusethischartforallsubsequentsamplinguntiltheprocesschanges 71 DeterminingifYourProcessis OutofControl 決定你的製程是否在穩定狀態 EstablishregionsA B andCasone two andthreesOneormorepointsfalloutsidethecontrollimits 2outof3consecutivepointsfallinthesameregionA4outof5consecutivepointsfallinthesameregionAorB6consecutivepointsincreasingordecreasing9consecutivepointsonthesamesideoftheaverage 14consecutivepointsalternatingupanddown15consecutivepointswithinregionC UsingannpChart建立不良數管制圖 Npchartsfornumberofnonconformingunits 以不合格品之數統計Convertedfrombasicp chart由p管制圖演變而來Multiplypbysamplesize n 不良率乘以樣本大小Formulas Settingupacchart建立缺點數管制圖 Takeabout20 25samplesfromtheprocess Eachsamplecontains1unit Foreachunitcountthenumberofoccurrencesfortheobservationofinterest Calculatetheaveragenumberofoccurrencesperunit ThisisC BAR Calculatetheupper lowercontrollimitfortheC BARchartusingthefollowingformulas UsinganuChart建立單位缺點數管制圖 Auchartisusedwhentheunitsizeinspectedfordefectsisnotconstant Inthesecasestheunitisoftenreferredtoasanareaofopportunity ni Theaverageoccurrenceperareaofopportunity i e thecenterline iscalculatedas Thesame25 variationrulediscussedforp chartsapplieshereaswell Controllimitsarecalculatedas 75 Figure 76 425Grams Mean平均值 ProcessDistribution製程分配 Distributionofsamplemeans樣本平均值分配 SampleMeansandtheProcessDistribution樣本平均值與製程分配 77 ProcessCapability製程能力 78 ProcessCapability製程能力 Lowerspecification Mean Upperspecification Twosigma Nominalvalue 79 ProcessCapability製程能力 Lowerspecification Mean Upperspecification Foursigma Twosigma Nominalvalue 80 ProcessCapability製程能力 Lowerspecification Mean Upperspecification Sixsigma Foursigma Twosigma Nominalvalue 81 ProcessCapability製程能力 Capable Verycapable Notcapable Processvariation 82 ProcessCapabilityCpk製程能力指數 83 MeaningsofCpkMeasuresCpk量測之意義 84 StatisticalProcessControl IdentifyandReduceProcessVariability統計製程管制 確認並降低製程變異 85 QualityControlApproaches品質管制方法 Statisticalprocesscontrol SPC 統計製程管制Monitorsproductionprocesstopreventpoorquality監控產品製程