2023/12/10ProcessFailureModeand

EffectsAnalysis

過程失效模式及后果分析(PFMEA)

PFMEA

PFMEA陶國2023/12/10ProprietaryInformation

專有信息YourFMEA(ControlPlan,ProcessCapability,etc.)maybeconsideredproprietaryandshouldnotbesharedwithanyoneoutsidethedivisionwithoutfirstconsultingyourmanagement.FMEA(控制計劃、過程能力等)可視為專有信息，在未事先征得管理部門同意之前，不得向部門以外的任何人透露。thisincludesthesharingofinformationwithyourcustomer

也不得向顧客透露有關(guān)信息。2023/12/10FormsandFormats

形式和格式Y(jié)ourcustomermighthaveaspecificformatorformthattheyrequire.Ifso,youwillneedtogettheirwrittenapprovaltouseanalternateformat.

顧客可能要求特定的格式或表單。如果是這樣，你只有征得他們的書面同意，才能采用其它格式。2023/12/10ProcessFMEA

過程FMEA何謂PFMEA何時作PFMEA何人作PFMEA如何作PFMEA16步工作步驟2023/12/10ProcessFMEA

過程FMEA何謂PFMEA何時作PFMEA何人作PFMEA如何作PFMEA16步工作步驟2023/12/10ProcessFMEA

過程FMEAananalyticaltoolusedbyaprocessdesignteamtoidentifypotentialproductfailurescausedbyfailureofthemanufacturingandassemblyprocesstomeetrequirements,andidentifycorrectiveactionstobetaken

是過程設(shè)計小組采用的一種分析方法，用于識別由于制造或裝配過程的失效而導(dǎo)致的潛在產(chǎn)品失效模式，并確定所應(yīng)采取的糾正措施。2023/12/10formalprocess

正式程序customerfocused

著眼于顧客usesengineeringjudgment,andharddatawhereitisavailable

利用工程經(jīng)驗(yàn)判斷和可靠的數(shù)據(jù)ProcessFMEA

過程FMEA2023/12/10PFMEAisfocussedontheProductPFMEA關(guān)注對產(chǎn)品的影響ProcessFMEA

過程FMEA2023/12/10ProcessFMEA

過程FMEA何謂PFMEA何時作PFMEA何人作PFMEA如何作PFMEA16步工作步驟2023/12/10WhendowedoaPFMEA?

何時進(jìn)行PFMEA？Whilethereisstilltimetobringaboutchangesintheprocessandintheproduct!

當(dāng)還有時間修改產(chǎn)品及工藝設(shè)計時！APFMEAdonesolelytofilloutaformandmeet“requirements”isjustanexercise

為了滿足QS9000要求而填寫PFMEA表格，僅是練習(xí)而已2023/12/10PFMEAisanoutputofthe"ProcessDesignandDevelopment"phaseofAPQP

PFMEA是APQP中“過程設(shè)計和開發(fā)”階段的產(chǎn)物WhendowedoaPFMEA?

何時進(jìn)行PFMEA？2023/12/10ItisderivedfromaDFMEA

在DFMEA之后進(jìn)行AnyDFMEAformsandsupportingdocumentsshoudbebroughttothePFMEAmeetings DFMEA表單和所有相關(guān)文件都應(yīng)帶入PFMEAItshouldbeanaturalpartofconceptdevelopment

應(yīng)成為過程設(shè)計的一個必要組成部分PFMEAisnever“finished”.itisalivingdocument

是動態(tài)文件WhendowedoaPFMEA?

何時進(jìn)行PFMEA？2023/12/10DoaPFMEA(oratleastreviewtheoldone)if:以下情況需進(jìn)行PFMEA(或至少評審過去的PFMEA)：theprocessisnew

是新的過程theproductisnew,orhasneverbeenmadewiththisprocess

新產(chǎn)品，或從未用本過程加工的產(chǎn)品anexistingprocesschanges

原有的過程發(fā)生變化customerrequirementsordesireschange

顧客要求或希望發(fā)生變化WhendowedoaPFMEA?

何時進(jìn)行PFMEA？2023/12/10DoaPFMEA(oratleastreviewtheoldone)if:以下情況需進(jìn)行PFMEA(或至少評審過去的PFMEA)：thecompetitive,business,orlegalenvironmentchanges

競爭環(huán)境、業(yè)務(wù)環(huán)境或法律環(huán)境發(fā)生變化PPAPconditionsapply

需提交PPAPactualfailuresoccur

發(fā)生實(shí)際失效WhendowedoaPFMEA?

何時進(jìn)行PFMFA？2023/12/10ProcessFMEA

過程FMEA何謂PFMEA何時作PFMEA何人作PFMEA如何作PFMEA16步工作步驟2023/12/10WhoperformsaPFMEA?

由誰進(jìn)行PFMEA？Across-functionalteamshouldbeused

由跨部門小組進(jìn)行Theleadershouldbetheprocess-responsibleengineer

小組組長應(yīng)是過程設(shè)計責(zé)任工程師2023/12/10Cross-FunctionalTeam

跨部門小組5-9peoplefrom，5-9人，由從事如下工作的人員組成

Design，設(shè)計Assembly，裝配manufacturing(operators,supervisors)，制造(操作工，班組長)Industrial,mfg.Andtoolengineering，工業(yè)工程，工藝及工裝設(shè)計quality，質(zhì)量管理materialsengineering，材料工程Servicepersonnel，機(jī)修Supplierofproductandmachinery，零件和設(shè)備供應(yīng)商Representativesfromthenextprocess,后續(xù)工序代表2023/12/10ProcessFMEA

過程FMEA何謂PFMEA何時作PFMEA何人作PFMEA如何作PFMEA16步工作步驟2023/12/10HowdowedoaPFMEA?

ASummary

怎樣進(jìn)行PFMEA？提要Assemblethecross-functionalPFMEAteam

組建跨部門PFMEA小組Listthefailuremodes,theireffects,andtheircauses

列出失效模式，后果以及原因2023/12/10Assess， 評估 theseverityoftheeffect(S)

后果的嚴(yán)重程度thelikelihoodofthecauses(O)

原因出現(xiàn)的可能性 andtheabilityofprocesscontrolstodetectfailuremodesand/ortheircauses(D)

過程控制探測失效模式和/或原因的能力HowdowedoaPFMEA?

ASummary

怎樣進(jìn)行PFMEA？提要2023/12/10Calculatetheriskprioritynumber(RPN)toprioritizecorrectiveactions

計算風(fēng)險順序數(shù)(RPN)以確定應(yīng)優(yōu)先采取的糾正措施Plancorrectiveactionsandassignowner

制訂糾正措施并落實(shí)責(zé)任人Performcorrectiveactionstoimprovetheproductorprocess,采取糾正措施以提高產(chǎn)品和過程質(zhì)量RecalculateRPN

重新估算RPNHowdowedoaPFMEA?

ASummary

怎樣進(jìn)行PFMEA？提要2023/12/10HowdowedoaPFMEA?

ASuggestion

怎樣進(jìn)行PFMEA？建議Doyourworkonscratchpaperfirst;astheteamreachesconsensus,recordtheinformationontheFMEAform

先在一張草稿紙上進(jìn)行分析；當(dāng)小組達(dá)成一致意見后，再將有關(guān)信息填在FMEA表上usefishboneandtreediagramsliberally

充分利用魚刺圖和樹形圖tryingtousetheFMEAformasaworksheetleadstoconfusionandmessed-upFMEAs

若將FMEA表當(dāng)做工作單使用，就會造成混亂，使FMEA一塌糊涂2023/12/10ProcessFMEA

過程FMEA何謂PFMEA何時作PFMEA何人作PFMEA如何作PFMEA16步工作步驟2023/12/101.Assembleateamand

planyouractivities

成立小組并制訂計劃PFMEAmustneverbedonebyanindividual,because

絕不能由個人單獨(dú)進(jìn)行PFMEA，因?yàn)椋篿ndividualeffortsproducebiasedresults,

由個人進(jìn)行會使結(jié)果出現(xiàn)偏差anyactionswillrequirebuy-infromvariousgroups

進(jìn)行任何活動，都需要從不同的組織取得信息2023/12/10Oneperson(e.g.theleader)shouldbeassignedtomaintainingtheFMEAform

應(yīng)指定一個人(如組長)保管FMEA表格BesuretowritethenamesandfunctionsoftheteammembersontheFMEAform

應(yīng)將小組成員的姓名和職責(zé)填入FMEA表格1.Assembleateamand

planyouractivities

成立小組并制訂計劃2023/12/102.Developaprocessflowdiagram

繪制過程流程圖UsetheProcessFlowDiagramformat

運(yùn)用正規(guī)的過程流程圖identifiesfabricate,move,storeandinspectoperations

辨別四種作業(yè)類型identifiesKeyCharacteristics

辨別關(guān)鍵特性2023/12/10

Supplier________________ Date_______________PartNumber_____________ RevisionLevel______PartDescription__________ Preparedby_________pressuremoldpartfabmovestoreinspstepoper.descr.item#KPCitem#KCCinspectpartforflashstorepartincontainercarrypartstoassyarea1noflash112342.Developaprocessflowdiagram

繪制過程流程圖2023/12/10過程流程圖moldpart注塑零部件fab加工move搬運(yùn)store存放insp檢驗(yàn)step步驟oper.descr.作業(yè)說明item#編號KPCitem#編號KCCinspectpartforflash檢驗(yàn)零件有無飛邊storepartincontainer將零部件放入周轉(zhuǎn)箱內(nèi)carrypartstoassyarea將零部件送往裝配區(qū)1noflash無飛邊pressure壓力112342023/12/102023/12/103.Listthefunction(s)of

eachoperation

列出每個操作的功能Afunctioniswhattheoperationdoes

功能系指該操作所起的作用Statethefunctionas，說明功能為：Verb+Object+Qualifier動詞+賓語+修飾詞

moldpart，零件成型

crimpterminalontocable

在線端壓接端子

formbendinpart,零件彎曲成型examples例如2023/12/10Don'tforgetauxiliaryfunctionsaswellaprimaryfunctions

基本功能和輔助功能都要考慮3.Listthefunction(s)of

eachoperation

列出每個操作的功能2023/12/104.Listthequality

requirements

列出質(zhì)量要求acustomerwantordesire

顧客的希望或要求couldseriouslyaffectcustomerperception

有可能嚴(yán)重影響顧客的看法couldleadtoacustomercomplaint

有可能導(dǎo)致顧客投訴2023/12/105.Listthepotentialprocessfailuremodes

列出可能的過程失效模式adefect,flaw,orotherunsatisfactoryconditionintheproductthatoccurswhentheprocessfailstomeettheprocessrequirements

由于過程未達(dá)到要求而導(dǎo)致的產(chǎn)品缺陷、瑕疵等不良狀態(tài)failuremodesshouldbewrittenintermsoftheconditionoftheproduct

失效模式體現(xiàn)在產(chǎn)品上2023/12/10TypicalFailureModes，幾種典型失效模式diameteroutofspec.，直徑超差missingseal，漏裝密封墊cutstrands，切破線皮misorientedpart，部件方向錯insufficientsolder，焊劑不足toomuchsolder，焊劑過量NFO，未充滿Flash，飛邊5.Listthepotentialprocessfailuremodes

列出可能的過程失效模式2023/12/10Note，注Assumethatincomingproductandmaterialsarecorrect

假設(shè)來料沒問題Assumethattheproductasdesignedwillmeetrequirements

假設(shè)產(chǎn)品設(shè)計能夠滿足客戶需求5.Listthepotentialprocessfailuremodes

列出可能的過程失效模式2023/12/106.Derivethepotentialeffectsofeachfailure

列出每一失效模式的所有可能后果Theramificationsoffailure

后果是失效模式的衍生事件Theeffectcanbeon，可能影響theultimatecustomer，最終用戶orintermediatecustomer(OEM,etc.)，中間用戶agovernmentregulation，法規(guī)thenextprocessstep，下序2023/12/10Customercomplaintsareausefulsourceofinformation

顧客抱怨是非常有用的信息來源6.Derivethepotentialeffectsofeachfailure

列出每一失效模式的所有可能后果2023/12/10Aneffectcanbe，后果可能為completelossoffunction，功能完全喪失degradationofperformanceorquality，質(zhì)量或性能降低damageofprocessequipment，設(shè)備受損injurytoanoperator，員工受傷shut-downofanassemblyline，停線6.Derivethepotentialeffectsofeachfailure

列出每一失效模式的所有可能后果2023/12/10Effectsoffailureoftenshowupasachainofevents,fromimmediateeffecttotheultimateeffectonthecustomer，失效的后果通常表現(xiàn)為從對顧客的直接影響到最終影響等一系列連鎖反應(yīng)ItisrecommendedthatthesechainsbedevelopedforeachfailuremodeandrecordedontheFMEAform

建議針對每一種失效模式找出這些連鎖反應(yīng)，并記錄在FMEA表上useatreediagram

運(yùn)用樹形圖6.Derivethepotentialeffectsofeachfailure

列出每一失效模式的所有可能后果2023/12/10Effectsontheprocess，對過程的影響:9-10 mayendangermachineoroperator， 可能導(dǎo)致設(shè)備或人員受損6-8 scrap，報廢4-5 sortandrework，檢驗(yàn)、返工2-3 reworkon-line，線上返工1 noeffect，無影響consideralsotheeffectsonthecustomer還要考慮對顧客的影響7.Assesstheseverity

ofeacheffect

評估每種后果的嚴(yán)重度2023/12/10Criteria:SeverityofEffect

Thisrankingresultswhenapotentialfailuremoderesultsinafinalcustomerand/oramanufacturing/assemblyplantdefect.Thefinalcustomershouldalwaysbeconsideredfirst.Ifbothoccur,usethehigherofthetwosev

Hazardous-withoutwarning10Veryhighseverityrankingwhenapotentialfailuremodeaffectssafevehicleoperationand/orinvolvesnoncompliancewithgovernmentregulationwithoutwarning.Ormayendangeroperator(machineorassembly)withoutwarning.

Hazardous-withwarning9Veryhighseverityrankingwhenapotentialfailuremodeaffectssafevehicleoperationand/orinvolvesnoncompliancewithgovernmentregulationwithwarning.Ormayendangeroperator(machineorassembly)withwarning.

VeryHigh8Vehicle/iteminoperable(lossofprimaryfunction).Or100%ofproductmayhavetobescrapped,orvehicle/itemrepairedinrepairdepartmentwitharepairtimegreaterthanonehour.

High7Vehicle/itemoperablebutatareducedlevelofperformance.Customerverydissatisfied.Orproductmayhavetobesortedandaportion(lessthan100%)scrapped,orvehicle/itemrepairedinrepairdepartmentwitharepairtimebetweenahalf-hourandanonehour.

Moderate6Vehicle/itemoperablebutComfort/Convenienceitem(s)inoperable.Customerdissatisfied.Oraportion(lessthan100%)oftheproductmayhavetobescrappedwithnosorting,orvehicle/itemrepairedinrepairdepartmentwitharepairtimelessthanahalf-hour.

Low5Vehicle/itemoperablebutComfort/Convenienceitem(s)operableatreducedlevelofperformance.Or100%ofproductmayhavetobereworked,orvehicle/itemrepairedoff-linebutdoesnotgotorepairdepartment.

VeryLow4Fit&Finish/Squeak&Rattleitemdoesnotconform.Defectnoticedbymostcustomers(greaterthan75%).Ortheproductmayhavetobesorted,withnoscrap,andaportion(lessthan100%)reworked.

Minor3Fit&Finish/Squeak&Rattleitemdoesnotconform.Defectnoticedby50%ofcustomers.Oraportion(lessthan100%)oftheproductmayhavetobereworked,withnoscrap,on-linebutout-of-station.

VeryMinor2Fit&Finish/Squeak&Rattleitemdoesnotconform.Defectnoticedbydiscriminatingcustomers(lessthan25%).Oraportion(lessthan100%)oftheproductmayhavetobereworked,withnoscrap,on-linebutin-station.

None1Nodiscernibleeffect.Orslightincoveniencetooperationoroperator,ornoeffect.2023/12/108.Determinepotentialcause(s)ofeachfailuremode

確定每一失效模式的可能原因Acauseoffailureishowthefailurecanoccurintheprocess，失效原因：過程為何會失效Shouldbewrittenintermsofsomethingintheprocessthatcanbecorrectedandcontrolled，應(yīng)表述為可糾正或可控制的因素Considerhumanerror,wear-outoftools,ambientconditions,andinteractionsoffactors，如人的過失，工裝磨損、環(huán)境條件以及因素間的相互作用2023/12/10Causesoffailureoftenshowupasachainofevents,fromimmediatecausetorootcause

失效通常是由一連串的原因造成的，從直接原因到根本原因ItisrecommendedthatthesechainsbedevelopedforeachfailuremodeandrecordedontheFMEAform

建議針對每一種失效模式，找出原因鏈，記入FMEA表useatreeorfishbonediagramtodevelop

可利用樹形圖或魚刺圖8.Cause(s)ofFailure

失效原因2023/12/109.Assessthelikelihoodof

occurrenceofeachcause

評估每種失效原因產(chǎn)生的可能性Usehistoricaldata(asabaseline)，利用歷史資料Takeimprovementsintoaccount，并考慮所作的改進(jìn)

Usestatisticalmodelsandcomparisonwithsimilarprocesses利用可靠性模型，與類似的過程進(jìn)行比較2023/12/109-10 Failurealmostinevitable，失效幾乎不可避免7-8 Similarprocessesthathaveoftenfailedin thepast，以前類似過程常常失效4-6 Similarprocessesthathaveoccasional failures，類似過程偶爾失效1-3 Similarprocessesthathaveexperienced isolatedfailures，類似過程僅有過個別失效9.Assessthelikelihoodof

occurrenceofeachcause

評估每種失效原因產(chǎn)生的可能性2023/12/10Occurence(O)ProbabilityLikelyFailureRates*

VeryHigh:

PersistentFailures>=100per

thousandpiecesVeryHigh:

PersistentFailures50perthousandpiecesHigh:

FrequentFailures20perthousandpieces

High:

FrequentFailures10perthousandpieces

Moderate:

OccasionalFailures5perthousandpiecesModerate:

OccasionalFailures2perthousandpieces

Moderate:

OccasionalFailures1perthousandpieces

Low:Relatively

FewFailures0.5perthousandpieces

Low:Relatively

FewFailures0.1perthousandpieces

Remote:Failure

isUnlikely<=0.010perthousandpieces109876543212023/12/10CausesandEffects

HarnessClampCause-and-effectchainradiusoutofspectoolisworntoolnotreplacedlackofmaintenanceprocedureclampcracksatbendbundlefallsoutrattlingnoiseCAUSEchainEFFECTchain2023/12/10CausesandEffects

WiringAssemblyEffectsTreeCrossedWireNofunctionFireinPlantOperatorInjuryDamagedEquip.Mustrepairvehicle2023/12/10CausesandEffects

WiringAssemblyCausesTreeCrossedWireBoardErrorOperatorErrorPoorInstruct.NottrainedOperistired2023/12/1010.ListtheCurrentProcessControls

列出現(xiàn)有過程控制Processcontrolscatchthedefectbeforetheproductreachesthecustomer，過程控制當(dāng)在產(chǎn)品到達(dá)顧客前發(fā)現(xiàn)缺陷!TherearethreeTypesofprocesscontrols,過程控制有三種類型:(1)preventthecauseoffailure,orreducetherateofoccurrence，防止原因出現(xiàn)或降低其出現(xiàn)的可能性(2)detectthecause(s)offailureandleadtocorrectiveactions，查明失效的原因并找出糾正措施(3)detectthefailuremode(s)，檢測失效模式2023/12/10Assigncurrentlyusedprocesscontrolstofailuremodesandcauses，針對失效模式或原因列出現(xiàn)行的過程控制手段Usedonsimilarprocessesinthepast，以前類似過程如何控制CanbeofanyType:1,2,or3,oranycombination，可以是1、2、3類或其組合Type1controlsaffectthelikelihoodofoccurrence,ifalreadypartofthedesign，若設(shè)計中已有體現(xiàn)，則第1類方法可降低原因出現(xiàn)的頻度Ifnone,write“None”，若沒有，則填“無”。10.ListtheCurrentProcessControls

列出現(xiàn)有過程控制2023/12/10Detectionisanassessmentoftheprobabilitythat，探測度為下列事件發(fā)生的概率atype2controlcandetectthecauseandleadtocorrectiveaction,第2類控制能夠發(fā)現(xiàn)原因并找到糾正措施 atype3controlcandetectafailure，第3類控制能夠在不良品到達(dá)顧客前發(fā)現(xiàn)缺陷

...beforetheproductreachesthecustomer!detectioncanalsoassesshoweffectivelyatype1controlcanpreventfailure，第1類控制能夠預(yù)防失效的有效程度11.Detectingfailure

探測度2023/12/1011.Detectingfailure

探測度DetectionRating(D)，探測度評分(D) 9-10 veryremotechancethiscontrol willdetectthecauseorfailure

查明失效或其原因的可能性極小

7-8 remotechance

，可能性很小

5-6 moderatetolowchance

，可能性不大

2-4 moderatelytoveryhighchance

，可能 性較大

1 almostcertainly(ifthepartpasses thistest,it'sOKtoship)

幾乎都可以查到(如能通過這項檢測，則可放 心發(fā)貨)2023/12/10Detection(D)CriteriaInspection

TypesSuggestedRangeofDetectionMethods

ABC

AlmostImpossibleAbsolutecertaintyofnon-detection.

XCannotdetectorisnotchecked.VeryRemoteControlswillprobablynotdetect.

X

Controlisachievedwithindirectorrandomchecksonly.RemoteControlshavepoorchanceofdetection.

XControlisachievedwithvisualchecksonly.VeryLowControlshavepoorchanceofdetection.

XControlisachievedwithdoublevisualinspectiononly.LowControlsmaydetect.

X

X

Controlisachievedwithchartingmethods,suchasSPC{StatisticalProcessControl}.ModerateControlsmaydetect.

X

Controlisbasedonvariablegaugingafterpartshaveleftthestation,orGo/NoGogaugingperformedon100%ofthepartsafterpartshaveleftthestation.ModeratelyHigh

Errordetectionisinsubsequentoperations,ORgaugingperformedonsetupandfirst-piececheck(forset-upcausesonly).Controlshaveagoodchancetodetect.XX

High

Errordetectionin-station,orerrordetectioninsubsequentoperationsbymultiplelayersofacceptance:supply,select,install,verify.Cannotacceptdescrepantpart.Controlshaveagoodchancetodetect.XX

VeryHighControlsalmostcertaintodetect.

X

X

Errordetectionin-station(automaticgaugingwithautomaticstopfeature).Cannotpassdiscrepantpart.VeryHighControlscertaintodetect.

X

Discrepantpartscannotbemadebecauseitemhasbeenerror-proofedbyprocess/productdesign.InspectionTypes:A.Error-proofed,B.Gauging,C