供应商最低能力要求NCA1003GBED2070521

StandardCode:NCA-1-003Priorcode:Title:MeasurementsystemvariationstudyforgaugesEdition:2Language:GBSecurityclassification:UNCLASSIFIEDPage.:1of:5Date:21/05/2007Translationversion:0ÍNDEX1.0OBJECT2.0SCOPE3.0DEFINITIONS4.0OPERATIVEMETHOD4.1VariationStudy4.2.AnalysisofResults4.3.DeterminingAccuracy4.4.DeterminingStability5.0ANNEXES1.0OBJECTThisstandarddefinestheminimumrequirementsforgaugesapproval(newandrefurbishedgauges)intermsofcapabilitywithinGamesaandSuppliers.2.0SCOPEThisStandardisapplicableforgaugevariationstudiesofgaugesusedtovalidateproductionpartswithinGamesaanditssuppliers.3.0DEFINITIONSThefollowingdefinitionsdescribethetypesoferrororvariationassociatedwithmeasurementsystemsandequipment.3.1.Accuracy:Theaccuracyisthedifferencebetweentheobservedaverageofmeasurementsandthetrueaverageofthesamecharacteristiconthesamepart.3.2.Repeatability:Thevariationinmeasurementsobtainedwhenoneoperatormeasuresseveraltimesthesameunit,usingthesameinstrumentandtechniquesonthesameparts.3.3.Reproducibility:Thevariationintheaverageofmeasurementmadebydifferentusers,orthesameuserindifferentlocations,usingthesamegaugewhilemeasuringthesameidenticalcharacteristiconthesamepart.3.4.Stability:Thisvariationreferstothedifferenceintheaverageofatleasttwosetsofmeasurementsobtainedwiththesameequipmentonthesamepartstakenatdifferenttimes.4.0OPERATIVEMETHODThemainobjectivesofperformingmeasurementsystemandequipmentcapabilitystudiesare:StandardCode:NCA-1-003Priorcode:Title:MeasurementsystemvariationstudyforgaugesEdition:2Language:GBSecurityclassification:UNCLASSIFIEDPage.:2of:5Date:21/05/2007Translationversion:0-Toprovideabasisforacceptanceofnewmeasurementsystemsandequipment.-Toperformanongoingprocesscontrolsystemforexistingmeasurementequipment.-Toevaluatemeasurementequipmentwithsuspectedperformancedeficiencies.Thesewillalsoresultinbetterunderstandingofthemagnitudeofmeasurementerroranditscontributiontoprocessvariationandkeepsuchuncertaintieswithinreasonablelimits,consistentwiththespecificrequirementofthatmeasurementapplication.4.1VariationStudyRepeatability&Reproducibility(R&R)study:Themorecomprehensivemethodofdetermininggaugeerroristheprecisionandreproducibilitystudy.Unlikethevariationstudy,thismethodprovidesanindicationofthecausesofgaugeerror.Thisisdonebydeterminingseparatelytheerrorsofprecisionandreproducibility.Forinstance,iflackofreproducibilityislargeincomparisontoprecision,itwouldindicate:-Operatortrainingisrequired-Calibrationsonthedialshouldbemoreclearlydefined.Ifthelackofprecisionislargeincomparisontoreproducibility,itwouldindicateoneormoreofthefollowing:-Gaugemaintenancemayberequired.-Gaugemayhavetoberedesignedtoimproverigidity.-Clampingorlocationofthepartinrelationtothegaugemayhavetobeimproved.Thenumberoftrialsandpartsmaybevaried.Although3operators,2trials,10partsaretherecommendedprocedure,severalalternativeshavebeenagreedbyGamesa:StandardCode:NCA-1-003Priorcode:Title:MeasurementsystemvariationstudyforgaugesEdition:2Language:GBSecurityclassification:UNCLASSIFIEDPage.:3of:5Date:21/05/2007Translationversion:0-3operators-2or3trials-5or10partsRemark1:Thenumberofpartsrequiredwilldependuponthesignificanceofthecharacteristicbeingcheckedandtherequiredlevelofconfidenceintheestimateofmeasurementvariation.Thesamplepartschosenforthestudyshallrepresenttherangeofvariationofthemanufacturingprocess.Remark2:Inanautomaticprocess(i.e.noinfluencefromtheoperator)onlyarepeatabilitystudyisperformedbyusingthesameprocedurewithonly“1operator”.StudyProcedure:Thisprocedureshallbebasedon3operators,2trialsand10parts.Method1:1.RefertooperatorsasA,BandC.Numbertheparts,1through10,sothatthenumbersarenotvisibletotheoperators.2.Calibratethegauge(withthemaster,ifpossible)beforethefirsttrial.3.OperatorAshallmeasuretenpartsandentertheresultsincolumnone.OperatorBshallmeasurethesame10partswithoutseeingoperatorA’sreadings,andentertheresultsincolumn5.OperatorCshallmeasurethesame10partswithoutseeingoperatorA’sorB’sreadingsandentertheresultsincolumn9.4.Step3aboveshallberepeatedusingadifferentorderofmeasurementofthe10parts.Enterdataincolumns2,6and10.Ifthreetrialsareneeded,repeatthecycleandenterdataincolumns3,7and11.Method2:Whendealingwithlargepartsizesorwherepartsarenotavailableatthesametime,steps3and4abovemaybechangedtothefollowing:1.OperatorAshallmeasurethefirstpartandrecordthereadingincolumn1.OperatorBshallmeasurethefirstpartandrecordthereadingincolumn5.OperatorCshallmeasurethefirstpartandrecordthereadingincolumn9.2.OperatorAshallre-measurethefirstpartandrecordthereadingincolumn2.OperatorBshallre-measurethefirstpartandrecordthereadingincolumn6.OperatorCshallre-measurethefirstpartandrecordthereadingincolumn10.Ifthreetrialsaretobeused,repeatthecycleandenterresultsincolumns3,7and11.Method3:Thismethodshallbeusedwhereoperatorsareindifferentshifts.OperatorAshallmeasureall5partsonceandenterthereadingsincolumn1.OperatorAshallrepeatthemeasurementsinadifferentorderandentercolumn2.RepeatthisprocesswithoperatorsBandContheothershifts.4.2.AnalysisofResultsTheresultsshallbeevaluatedtodetermi