MSAIntroductionTechnicalItemsIntroductionMSABackgroundGaugeR&RMeasurementSystemAnalysis1MSAIntroduction•MSAisabbreviationofMeasurementSystemAnalysis•MSAisoneof5toolswhenapplyTS16949qualitysystem•NormallyMSAisonlytoberequiredfromautoindustries,however,moreandmoredifferenttypeofindustriesapplytheMSAsystem.•Theapplicationpurpose:–TS16949qualitysystemrequired–Betterevaluationandcontrolforinternalmeasurementsystem–Betterevaluationandcontrolforexternalmeasurementsysteminvendorplants.2MSAIntroduction•WhatismeasurementsystemMeasurementsystemisthecollectionofinstrumentsorgauges,standards,operations,methods,fixtures,software,personnel,environmentandassumptionsusedtoquantifyaunitofmeasureorfixassessmenttothefeaturecharacteristicbeingmeasured,thecompleteprocessusedtoobtainmeasurement.•WhattodoisinmeasurementsystemanalysisStudyingmeasurementsystemisaccordingtotopicsofhowvariancebecreated,whichvariancecanbecorrected,whichcan’t,howtokeepmeasurementsystemincapableandreliableusing;andGR&R.3CustomerCustomerManagementResponsibilityResourceManagementInputProductRealizationOutputMeasurementinQualityManagementSystemMeasure,Analyze,ImproveContinuousimprovementQualityManagementSystemSatisfactionRequirementProductMSAinQualitySystem4•Ifmeasurementsystemisn’tgood,goodoutputmaybemeasurednotgood,andbadoutputmaybemeasuredgood.ProcessMaterialOperatorMeasureOutputGoodNotGoodMeasureMSAinProcessMachineMethodEnvironmentMeasure5Generalconcepts:•Everyprocessproducesa‘product’•Everyproductpossesses‘Qualities’(Feathers)•Everyqualityfeathercanbemeasured•Totalvariation=productvariation+measurementvariation•Somevariationinherentinsystemdesign•SomevariationisduetoafaultyperformanceofthesystemGeneralconceptionsofMSA6ComponentsofMeasurementSystem:•EquipmentorGageTypeofGage:-Attribute:go-nogo,visionsystems-Variable:calipers,probe,coordinatemeasurementmachines•UnitofMeasurement-discrimination-Atleast1/10of6*processstandarddeviation(6s)-Otherrules:atleast1/10oftolerance•Operator&OperatingInstructions•Partlocatingororientationscheme-Agagemustbeabletoconsistentlylocatethepartbeingmeasured.TechnicalItemsIntroduction7Measurementsystem:•Thecollectionofoperations,procedures,gaugesandpersonnelusetoobtainmeasurementofworkpiececharacteristics.TechnicalItemsIntroductionGauge:•Adeviceusestoobtainmeasurements.8Accuracy:•Differencebetweenthetrueaverageandtheobservedaverage(trueaveragemaybeobtainedusingamoreprecisemeasuringtool)TechnicalItemsIntroductionHowtomakesureyourmeasurementsystemisenoughaccuracy?9Repeatability:•Repeatability(Precision).Thevariationinmeasurementobtainedwithonemeasurementwhenusedbyoneoperatortomeasureanidenticalcharacteristiconthesamepart.(EV:EquipmentVariation)TechnicalItemsIntroductionHowtovalidaterepeatability?10Reproducibility:•Thevariationintheaverageofmeasurementsmadebydifferentoperatorsusingthesamemeasurementinstrumentwhenmeasuringidenticalcharacteristiconthesamepart.(AV:AppraiserVariation)TechnicalItemsIntroductionHowtovalidatereproducibility?11Bias:•Thedifferencebetweentheobservedaverageofmeasurementsandthereferencevalue.•Whenreferencevalueisgettingfrommeasurementbybetterresolutioninstrument,biasrespectsaccuracy.•Itispartofmeasurementsystemerror.TechnicalItemsIntroductionHowtodecreasebiasbyappraiser,fixtureandmeasurementinstrument?12Stability:•Thetotalvariationinthemeasurementsobtainedwithameasurementsystemonthesamemasterorpartswhenmeasuringsinglecharacteristicsoveranextendedtimeperiod.•Thestabilityshowedhowbiasvalueischangingperextendedtimeperiod.TechnicalItemsIntroductionHowtokeepthemeasurementsystemstableenough?13TimeREFvalueLinearity:•Thedifferenceinthebiasvaluesthroughtheexpectedoperatingrangeofthegauge.•Theinterrelationsbetweenmultipleandindependentbiasvaluesinfulloperatingrangeofthegauge.•Itispartofmeasurementsystemerror.TechnicalItemsIntroductionHowtokeepmeasurementinstrumentworkingunderlinearitythroughrightoperatingrange?14MeasurementvalueReferencevalueGoodlinearityBadlinearityDifferencebetweenPrecisionandAccuracy:TechnicalItemsIntroductionDoyourealizewhyimprecisioncan’tbecorrected?15DifferencebetweenAccuracyandStability:TechnicalItemsIntroduction16Twotypeoferrorstowardsdecisionofproductquality:TechnicalItemsIntroduction17LowerlimitUpperlimitORTypeIerror:makejudgmentofgoodproductstobebad.TypeIIerror:makejudgmentofbadproductstobegood.LowerlimitUpperlimitORMSABackgroundBasedonQS-90004.11.4,•Itisnecessarytodoproperanalysis,inordertostudyvarianceproducedfrommeasurementsystem.Therequirementmustbeusedonwhatcontrolplanmentionsmeasurementsystem.•Therequirementistostudywhatcontrolplanmentionedproductcharacteristicsandprocesscharacteristics.18MSABackgroundMeasurementsystemerror•Thecumulativeeffectofallthesourcesofvariationinthemeasurementsystemisofoftencalledmeasurementsystemerror,orsometimesjust‘error’.•Y=X+εYreferstomeasuredvalue;Xreferstotruthvalue;εreferstomeasurementsystemerror.•Theerrorεisinteractionofbias,reproducibility,repeatability,linearityandstability.19MSABackgroundCompositionofmeasurementsystemerrorBasicanalysismodelofsourc