Failure_Mode_and_Effects_Analysis__FMEA__for_publi

UNDERSTANDINGTHEFUNDAMENTALDEFINITIONSANDCONCEPTSOFFMEASFailureModeandEffectsAnalysis(FMEA)MaterialforthispresentationisbasedonthebookEffectiveFMEAs,byCarlS.Carlson,publishedbyJohnWiley&Sons,©2012DefinitionofFMEAFailureModeandEffectsAnalysis(FMEA)isamethoddesignedto:yIdentifyandfullyunderstandpotentialfailuremodesandtheircauses,andtheeffectsoffailureonthesystemorendusers,foragivenproductorprocess.yAssesstheriskassociatedwiththeidentifiedfailuremodes,effectsandcauses,andprioritizeissuesforcorrectiveaction.yIdentifyandcarryoutcorrectiveactionstoaddressthemostseriousconcerns.WhatisFMEA?AnFMEAisanengineeringanalysisydonebyacross-functionalteamofsubjectmatterexpertsythatthoroughlyanalyzesproductdesignsormanufacturingprocessesyearlyintheproductdevelopmentprocess.yFindsandcorrectsweaknessesbeforetheproductgetsintothehandsofthecustomer.WhatisFMEA?AnFMEAshouldbetheguidetothedevelopmentofacompletesetofactionsthatwillreduceriskassociatedwiththesystem,subsystem,andcomponentormanufacturing/assemblyprocesstoanacceptablelevel.WhatisFMEA?yPerforminganFMEAjusttofillacheckboxintheProductDevelopmentProcessandthenfilingitaway,nevertobeseenagain,isawasteoftimeandaddsnovalue.yIfnotforuseasguidancethroughthedevelopmentprocess,whywastethetimeandresourcestodoitinthefirstplace?yIfeffectivelyusedthroughouttheproductlifecycle,itwillresultinsignificantimprovementstoreliability,safety,quality,delivery,andcost.PrimaryObjectiveofFMEATheprimaryobjectiveofanFMEAistoimprovethedesign.yForSystemFMEAs,theobjectiveistoimprovethedesignofthesystem.yForDesignFMEAs,theobjectiveistoimprovethedesignofthesubsystemorcomponent.yForProcessFMEAs,theobjectiveistoimprovethedesignofthemanufacturingprocess.PrimaryObjectiveofFMEATherearemanyotherobjectivesfordoingFMEAs,suchas:yidentifyandpreventsafetyhazardsyminimizelossofproductperformanceorperformancedegradationyimprovetestandverificationplans(inthecaseofSystemorDesignFMEAs)yimproveProcessControlPlans(inthecaseofProcessFMEAs)yconsiderchangestotheproductdesignormanufacturingprocessyidentifysignificantproductorprocesscharacteristicsydevelopPreventiveMaintenanceplansforin-servicemachineryandequipmentydeveloponlinediagnostictechniquesTypesofFMEAsThethreemostcommontypesofFMEAsare:ySystemFMEAyDesignFMEAyProcessFMEASystemFMEAAnalysisisathighest-levelanalysisofanentiresystem,madeupofvarioussubsystems.Thefocusisonsystem-relateddeficiencies,includingysystemsafetyandsystemintegrationyinterfacesbetweensubsystemsorwithothersystemsyinteractionsbetweensubsystemsorwiththesurroundingenvironmentysingle-pointfailures(whereasinglecomponentfailurecanresultincompletefailureoftheentiresystem)SystemFMEAThefocus(continued)yfunctionsandrelationshipsthatareuniquetothesystemasawhole(i.e.,donotexistatlowerlevels)andcouldcausetheoverallsystemnottoworkasintendedyhumaninteractionsyserviceSomepractitionersseparateouthumaninteractionandserviceintotheirownrespectiveFMEAs.DesignFMEAAnalysisisatthesubsystemlevel(madeupofvariouscomponents)orcomponentlevel.TheFocusisonproductdesign-relateddeficiencies,withemphasisonyimprovingthedesignyensuringproductoperationissafeandreliableduringtheusefullifeoftheequipment.yinterfacesbetweenadjacentcomponents.DesignFMEAusuallyassumestheproductwillbemanufacturedaccordingtospecifications.ProcessFMEAAnalysisisatthemanufacturing/assemblyprocesslevel.TheFocusisonmanufacturingrelateddeficiencies,withemphasisonyImprovingthemanufacturingprocessyensuringtheproductisbuilttodesignrequirementsinasafemanner,withminimaldowntime,scrapandrework.ymanufacturingandassemblyoperations,shipping,incomingparts,transportingofmaterials,storage,conveyors,toolmaintenance,andlabeling.ProcessFMEAsmostoftenassumethedesignissoundFMEADefinitionsandExamplesResponsiblePersonActionsTakenTargetCompletionDateEffectiveCompletionDateSeverityOccurrenceDetectionRPN1234567889101112GenericFMEAWorksheetRevisedRankingsItemPotentialEffect(s)ofFailureSeverityPotentialCause(s)ofFailureOccurrenceCurrentDesignControls(Prevention)CurrentDesignControls(Detection)DetectionRPNRecommendedAction(s)PotentialFailureModeFunctionItem1An“item”isthefocusoftheFMEAproject.yForaSystemFMEAthisisthesystemitself.yForaDesignFMEA,thisisthesubsystemorcomponentunderanalysis.yForaProcessFMEA,thisisusuallyoneofthespecificstepsofthemanufacturingorassemblyprocessunderanalysis,asrepresentedbyanoperationdescription.Example:BicyclehandbrakesubsystemThisillustrationisfromthebookEffectiveFMEAs,byCarlS.Carlson,publishedbyJohnWiley&Sons,©2012Function2A“function”iswhattheitemorprocessisintendedtodo,usuallytoagivenstandardofperformanceorrequirement.yForDesignFMEAs,thisistheprimarypurposeordesignintentoftheitem.yForProcessFMEAs,thisistheprimarypurposeofthemanufacturingorassemblyoperation.yFunctionsaretypicallydescribedinaverb-nounformat.yTherecanbemanyfunctionsforeachitemoroperation.Example:Providesthecorrectleveloffrictionbetweenbrakepadassemblyandwheelrimtosafelystopbicycleintherequireddistance,underalloperatingconditions.ThisillustrationisfromthebookEffectiveFMEAs,byCarlS.Carlson,publishedbyJoh