博世汽车SPC资料资料下载.pdf
- 文档编号:5970128
- 上传时间:2023-05-05
- 格式:PDF
- 页数:38
- 大小:812.75KB
博世汽车SPC资料资料下载.pdf
《博世汽车SPC资料资料下载.pdf》由会员分享,可在线阅读,更多相关《博世汽车SPC资料资料下载.pdf(38页珍藏版)》请在冰点文库上搜索。
“Setofinterrelatedorinteractingactivitieswhichtrans-formsinputsintooutputs.”Thisbookletonlyreferstomanufacturingorassemblyprocesses.StableprocessAstableprocess(processinastateofstatisticalcontrol)isonlysubjecttorandominfluences(causes).Especiallythelocationandvariationoftheprocesscharacteristicarestableovertime(referto4)CapableprocessAprocessiscapablewhenitisabletocompletelyfulfillthespecifiedrequirements.Referto11fordeterminingcapabilityindices.ShewhartqualitycontrolchartQualitycontrolchartformonitoringaparameteroftheprobabilitydistributionofacharacteristic,inordertodeterminewhethertheparametervariesfromaspecifiedvalue.SPCSPCisastandardmethodforvisualizingandcontrolling(openorclosedloop)processes,basedonmeasurementsofrandomsamples.ThegoalofSPCistoensurethattheplannedprocessoutputisachievedandthatcorrespondingcustomerrequirementsarefulfilled.SPCisalwayslinkedto(manualorsoftwaresupported)useofaqualitycontrolchart(QCC).QCCsarefilledoutwiththegoalofachieving,maintainingandimprovingstableandcapableprocesses.Thisisdonebyrecordingprocessorproductdata,drawingconclusionsfromthisdataandreactingtoundesirabledatawithappropriateactions.-7-Thefollowingdefinitionsarethesameasoratleastequivalenttothosein6.LimitingvalueLowerorupperlimitingvalueLowerlimitingvalueLowestpermissiblevalueofacharacteristic(lowerspecificationlimitLSL)UpperlimitingvalueHighestpermissiblevalueofacharacteristic(upperspecificationlimitUSL)ToleranceUpperlimitingvalueminuslowerlimitingvalue:
LSLUSLT=TolerancerangeRangeofpermissiblecharacteristicvaluesbetweenthelowerandupperlimitingvaluesCenterpointCofthetolerancerangeTheaverageofthelowerandupperlimitingvalues:
2LSLUSLC+=Note:
Forcharacteristicswithone-sidedlimits(onlyUSLisspecified),suchasroughness(Rz),formandposition(e.g.roundness,perpen-dicularity),itisnotappropriatetoassume0=LSLandthustoset2/USLC=(alsorefertothefirstcommentinSection4.1.1.1).PopulationThetotalofallunitstakenintoconsiderationRandomsampleOneormoreunitstakenfromthepopulationorfromasub-population(partofapopulation)RandomsamplesizenThenumberofunitstakenfortherandomsampleMean(arithmetic)Thesumoftheixmeasurementsdividedbythenumberofmeasurementsn:
=niixnx11MedianofasampleForanoddnumberofsamplesputinorderfromthelowesttohighestvalue,thevalueofthesamplenumber(n+1)/2.Foranevennumberofsamplesputinorderfromthelowesttohighestvalue,normallytheaverageofthetwosamplesnumberedn/2and(n/2)+1.(alsoreferto13)Example:
Forasampleof5partsputinorderfromthelowesttothehighestvalue,themedianisthemiddlevalueofthe5values.VarianceofasampleThesumofthesquareddeviationsofthemeasurementsfromtheirarithmeticmean,dividedbythenumberofsamplesminus1:
()=niixxns12211StandarddeviationofasampleThesquarerootofthevariance:
2ss=RangeThelargestindividualvalueminusthesmallestindividualvalue:
minmaxxxR=-8-2.PlanningPlanningaccordingtothecurrenteditionofQSP0402“SPC”,whichdefinesresponsibilities.SPCcontrolofacharacteristicisonepossibilityforqualityassuranceduringmanufacturingandtestengineering.2.1SelectionofProductCharacteristicsSpecificationofSPCcharacteristicsandtheirprocessesshouldbedoneasearlyaspossible(e.g.bythesimultaneousengineeringteam).Theycanalso,forexample,beanoutputoftheFMEA.ThisshouldtakeFunction,Reliability,Safety,Consequentialcostsofdefects,Thedegreeofdifficultyoftheprocess,Customerrequests,andCustomerconnectioninterfaces,etc.intoaccount.The7W-questionscanbehelpfulinspecifyingSPCcharacteristics(referto“datacollection”in“ElementaryQualityAssuranceTools”8):
Exampleofasimpleprocedureforinspectionplanning:
WhydoIneedtoknowwhat,when,whereandhowexactly?
HowlargeistheriskifIdontknowthis?
Note:
ItmaybenecessarytoaddnewSPCcharacteristicstoaprocessalreadyinoperation.Ontheotherhand,therecanbereasons(e.g.changeofamanufacturingmethodorintro-ductionof100%testing)forreplacingexistingSPCcontrolwithotheractions.SPCcharacteristicscanbeproductorprocesscharacteristics.Why?
Whichorwhat?
Whichnumberorhowmany?
Where?
Who?
When?
Withwhatorhowexactly?
2.1.1TestVariableDefinitionofthe“SPCcharacteristic”,directorindirecttestvariable.Note:
Ifacharacteristiccannotbemeasureddirectly,thenasubstitutecharacteristicmustbefoundthathasaknownrelationshiptoit.-9-2.1.2ControllabilityTheprocessmustbeabletobeinfluenced(controlled)withrespecttothetestvariable.Normallymanufacturingequipmentcanbedirectlycontrolledinamannerthatchangesthetestvariableinthedesiredway(smallcontrolloop).Accordingto
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 汽车 SPC 资料