TestMethodMaterials
GMW3405
SeamFatigueforAutomobileTextiles
1Scope
Thisprocedureisusedtodeterminetheabilityofauto-motivetextilematerialstoresistseamfatiguefailureswhenusedinsewnassemblies.
Note:Nothinginthistestmethodsupersedesappli-cablelawsandregulationsunlessaspecificexemp-tionhasbeenobtained.
Note:IntheeventofaconflictbetweentheEng-lishandthedomesticlanguage,theEnglishlanguageshalltakeprecedence.
4TestMaterial
4.1SewingThread.Sizeof(1022±111)decitexNy-lonorPolyesterthreadortheproductionintentsewingthread.
5TestMethod
5.1SummaryofTestMethod.Thismethodeval-uatesseamfatigueusingaseriesofloadingandun-loadingcyclesappliedtoaseamsewninatextilematerialtestspecimen.Theseamappearanceandneedleholeelongationisevaluateduponcompletionofthecycles.
5.2TestSamplePreparation.
5.2.1Unlessotherwisespecifiedintherelevantmate-rialspecification,conditioningshallbeperformedac-cordingtoGMW3221CodeA.
5.2.2Cutsixspecimenseach100x100mmwitheachcutedgeeitherparallelorperpendiculartothemachinedirectionofthematerial.
5.2.3Placetwospecimensfacetoface(showsurfacetoshowsurface)withthematerialmachinedirectionofeachtestspecimensparallel.Usingalockstitch,jointhetwospecimenswithaseamperpendiculartothematerialmachinedirectionatadistanceof(10±1)mmfromoneedgewithastitchlengthof(5±0.5)mm.Theendsofthesewnassemblycanbebackstitchedforapproximately10mmoraknotcanbetiedwiththethreads.Cuteachendofthesewnassembly(25±1)mmfromtheedgeandperpendiculartotheseamlineforalengthofapproximately90mmbeingcarefulnottocuttheseamthreads.ThistestspecimentobereferredtoasWarp/Warp.
5.2.4Repeat5.2.3butsewtheseamparalleltothematerialmachinedirection.ThistestspecimentobereferredtoasWeft/Weft.
5.2.5Repeat5.2.3butplacethematerialmachinedi-rectionofthetwospecimensperpendiculartoeachotherandsewtheseamonanyside.Thistestspeci-mentobereferredtoasWarp/Weft.5.3TestProcedure.
5.3.1Placeaclamponeachendofthetestspeci-men.Thedistancebetweentheclampsclampedon
2References
Note:Onlythelatestapprovedstandardsareappli-cableunlessotherwisespecified.2.1Normative.None.2.2GM.
GMW3221GM9129P
ISC-C93-001TM8
3TestEquipment
3.1SeamFatigueTester.OgawaSeikiModelATD-2orequivalent.
Note:OgawaSeikiCo.Ltd.;TokyoCentralP.O.Box1618;Tokyo,Japan;Tel.Tokyo03-3367-8211;Fax.Tokyo03-3367-8581.8592.3.1.150mmwideclamps.
3.2SewingMachine.Capableofproducingalockstitchedseamwithastitchlengthof5mmperstitch(10stitches/50mm).
3.3SewingNeedle.Number23roundunlessother-wisespecifiedbyaspecificGMregionandrecordedontheconstructionspecificationandtestdatareport.3.4Metricrulerorcalipers.
3.5ApparatusforconditioningtotheappropriaterequirementsasdescribedinGMW3221CodeA,unlessotherwisespecifiedintherelevantmaterialsspecification.
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GMW3405GMWORLDWIDEENGINEERINGSTANDARDS
7.3DeviationsfromthisTestMethod.Deviationsfromtheconditionsofthistestmethodshallhavebeenagreeduponbetweensupplierandvehiclemanufac-turer.Alldeviationsshallbespecifiedonthecompo-nentdrawings,materialspecifications,etc.andshallbeindicatedontestcertificates,reports,etc.
thetestspecimenshouldbe(120±1)mm.Theseamshouldbecenteredbetweentheclamps.
Note:Ifthetestspecimenelongatestomorethan140mmbetweentheclampsduringthetest,itshouldbere-clampedtothe(120±1)mmoriginalspacing.5.3.2Setthecounterfortherequirednumberofcy-clesasspecifiedintherelevantmaterialspecificationandrunthetest.Testshouldberunataspeedof(30±1)cycles/minutewiththeloadweightof(3±0.1)kg.
8Safety
Thismethodmayinvolvehazardousmaterials,opera-tionsandequipment.Thismethoddoesnotproposetoaddressallthesafetyproblemsassociatedwithitsuse.Itistheresponsibilityoftheuserofthismethodtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimita-tionspriortouse.
6EvaluationandRating
6.1Evaluatethetestspecimensforneedleholeelon-gationwhilethetestspecimenisstillonthemachinewiththe(3±0.1)kgweightappliedoronadevicethatseparatelyappliesthe(3±0.1)gload.Withcalipersorametricruler,measurethemaximumlengthoftheholescreatedoneachsideoftheseamduetoneedleholeelongation.Themeasurementforneedleholeelongationisfromthecenterofthestitchlinetotheothersideoftheelongatedhole.
6.2Evaluatetheappearanceoftheseamaftertest-ing.Makenoteofanyseamfractures,yarnslippage,yarnbreaksoranyotherobjectionableappearancechanges.
7Report
7.1Reportthelargestneedleholeelongation,inmm,foreachtestspecimen.
7.2Reportanynotedobjectionableappearancechanges.
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9CodingSystem
Thistestmethodshallbereferencedinotherdocu-ments,drawings,VTS,CTS,etc.asfollows:TesttoGMW3405
10ReleaseandRevisions
10.1Release.ThistestmethodwasapprovedandpublishedinOctober2000.
ThistestmethoddevelopedbytheWWFabricSpecificationTeamtomakecommonthecurrenttestmethodsusedforSeamFatigue.ThesetestmethodsareGM9129P(NA&GMB)andISC-C93-001TM8(Isuzu).
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October2000
