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1、Designation:D5170?98(Reapproved2015)StardTestMethodfPeelStrength(“T”Method)ofHookLoopTouchFasteners1ThisstardisissuedunderthefixeddesignationD5170thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptio

2、ninthecaseofrevisiontheyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thistestmethodcoversthemeasurementofthepeelst

3、rengthofhooklooptouchfastenersusingarecdingconstantrateofextensiontensiletestingmachine(CRE).1.2Thevaluesstatedininchpoundunitsaretoberegardedasstard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatarep

4、rovidedfinfmationonlyarenotconsideredstard.1.3Thisstarddoesnotpurpttoaddressallofthesafetyproblemsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminethe

5、applicabilityofregulatylimitationspritouse.2.ReferencedDocuments2.1ASTMStards:2D618PracticefConditioningPlasticsfTesting3.SignificanceUse3.1Thistestmethodgivesameasureofakeypropertyofhooklooptouchfastenerswhichisofintere

6、sttousersofsuchdevices.Thisisameansofdeterminingtheresistancetoseparationwhenfcesareappliednmaltothelineofseparationofthefastener.3.2Thefceregisteredinapeeltestisirregularasaconsequenceempiricalmethodshavehadtobedevelope

7、dtoobtainusablevaluesrelatedtopeelstrength.Inspiteoftheempiricalnatureofthereptedvaluesitisbelievedtheyreflectcomparativeperfmanceofsimilartouchfastenerstestedmeasuredinthesameway.3.3Twooptionalmethodsofcalculationarepro

8、vided:integrataverageaverageoffivehighestpeaks.Thesetestmethodsarenotequivalent.Generallytheintegrataveragewillbelowerthantheaverageofthefivehighestpeaks.3.4Thehighestpeakswhichreflectthefcerequiredtoseparateahookloopclo

9、surebearnosimplerelationshiptotheaveragefce(integrataverage).Theaverageofthefivehighestpeaksbetterreflectperfmancebuttheintegratresultsmaybeusedtoacterizeaclosurefqualitycontrolpurposes.Theintegrataverageisrelativelyeasy

10、tocalculategiventheproperequipment.3.5Inthecaseofadisputearisingfromdifferencesinreptedtestresultswhenusingthistestmethodfacceptancetestingofcommercialshipmentsthepurchaserthesuppliershouldconductcomparativeteststodeterm

11、ineifthereisastatisticalbiasbetweentheirlabaties.Competentstatisticalassistanceisrecommendedftheinvestigationofbias.Asaminimumthetwopartiesshouldtakeagroupoftestspecimenswhichareashomogenousaspossiblewhicharefromalotofho

12、okloopofthetypeinquestion.Thetestspecimensshouldthenberomlyassignedinequalnumberstoeachlabatyftesting.TheaverageresultsfromthetwolabatiesshouldbecomparedusingStudent’sttestanacceptableprobabilitylevelchosenbythetwopartie

13、sbefethetestingbegan.Ifabiasisfoundeitheritscausemustbefoundcrectedthepurchaserthesuppliermustagreetointerpretfuturetestresultsinthelightoftheknownbias.4.Apparatus4.1Roller—consistingofasmoothsteelsurfaceapproximately43?

14、4in.(121mm)indiameter21?4in.(57mm)wideequippedwithahlelength41?8in.(105mm)fpropellingtherollerbackfthwithoutaddingadditionalweighttothespecimenbeingrolled(SeeFig.1).Theweightoftheroller(includingthehle)is1161?4lbs.(4994g

15、6114g).4.2TestingMachine—Aconstantrateofextension(CRE)tensiletestershallbeused.Thetestershallhavetwoclampswithcentersinthesameplaneparalleltothedirectionofthemotionofthestressingclampsoalignedthattheywillholdthespecimene

16、ndswhollyinthesameplaneameansofmovingthestressingclampataunifmrateof12.060.51ThistestmethodisunderthejurisdictionofASTMCommitteeD13onTextilesisthedirectresponsibilityofSubcommitteeD13.54onSubassemblies.Currenteditionappr

17、ovedFeb.12015.PublishedApril2015.iginallyapprovedin1991.Lastpreviouseditionapprovedin2010asD517098(2010).DOI:10.1520D517098R15.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookof

18、ASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.Copyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.UnitedStates18.2fromthefourspecimensofhookloopthefirstclosuret

19、obetestedreferringtoFig.2preparethefirstclosurespecimenwiththemarkedarrowsasshowninSequence1.NOTE1—Thereasonftestingallfourpossibleclosureconfigurationsisthatthehookloopmaterialbothmayhavedirectionality(thatisthehooksloo

20、psmaynotbeperpendiculartothebasefabricofwhichtheyareacomponent)affectthepeelfce.8.2.1CarefullyalignsuperimposethehookstripovertheloopstripsothatthehookstripcoverstheloopstripthemarkedendsarematchedasshowninFig.2Sequence1

21、.8.2.2Placeaflatsteelplate8in.(20cm)long11?2in.(4cm)wideweighing4pounds(1814gm)(approximatelyequivalentto1?2lbsperin2ofclosure)ontotheclosurecompletelycoveringitslowlywithoutaddinganyhpressure.After2sremovetheplate.Thisi

22、nitialmatingoftheclosureisdonetocreatejustenoughhookloopengagementsoastobeabletocontinuewiththetestprocedure.8.2.3Securelyfastenthetwoendsofthematedhooklooptoahardflatsurfacesuchasametalplatetabletopetc.usingmaskingtapes

23、taplesclampshookloopstrapsthelike.8.2.4Pushtherollerwithoutaddingweight(fromtheendoftheclosuretobeseparatedbythetensiletester)overtheentirelengthofthejoinedstripsthenpullitbackovertheentirelength.Thisconstitutesonecyclea

24、continuousuninterruptedbackfthmotionoftherollerwithoutliftingitfromthematerial.Eachcycleshouldtakeabout2s.8.2.4.1Perfmfive(5)cycleswiththerollerwithoutliftingitfromthematerial.Removethespecimenfromtheholderthenhseparatet

25、hisinitialclosurefromtheendindicatedtobejoinedinthetesterclampsasindicatedinFig.2Sequence1.8.2.5Thenagaincarefullyalignsuperimposethehookstripovertheloopstripsothatthehookstripcoverstheloopstripthemarkedendsasdescribedin

26、6.1.2arematched.Thenagainmaketheclosureasdescribedin8.2.1–8.2.4above.Thiswillresultina“ReadyfPeelTest”specimen.8.3Preparethesecondclosurespecimenasdescribedin8.2.1–8.2.4exceptwiththemarkedendsasshowninSequence2ofFig.2.8.

27、4Preparethethirdclosurespecimenasdescribedin8.2.1–8.2.4exceptwiththemarkedendsasshowninSequence3ofFig.2.8.5Preparethefourthclosurespecimenasdescribedin8.2.1–8.2.4exceptwiththemarkedendsasshowninSequence4ofFig.2.8.6Inthes

28、equenceinwhichtheclosurespecimenswerepreparedthemftestinginthetensiletester.GentlyseparateapproximatelyoneinchofclosureattheendtobeplacedintotheclampsasindicatedinFig.2inthesequenceshown.Thiswillcreatetwofreeendstobeedin

29、tothetensiletester.8.7Positiontheclampsofthetensiletestersotheyare161?8in.(25.463mm)apart.Placethefreeendsofthespecimentobetestedintheclampsofthetesterwiththehookstripinthemovingclamp.Thepointofseparationshouldbeapproxim

30、atelycenteredalignedapproximatelyparalleltotheclamps.Useaclampseparationspeedof12.060.5in.min(305613mmmin).Ifanintegratisusedsetitsuchthatthefirstlastinchesofseparationarenotincludedintheresults.8.8Observethetpaperproduc

31、edbytheautographicrecder.Ajaggedlinehavingmultiplepeakswillbeproduced.MakenoteontherecdingtofthetestspecimennumbersequencenumberfromFig.2.9.Calculation9.1Calculatetheaveragepeelfceofthesampleusingthe“averageoffivehighest

32、peaks”method.9.1.1Markfivesuccessiveequalptionsonthetexcludingthefirstlastinchofseparation.9.1.2Determinethehighestpeakvalueineachption.9.1.3Calculatetheaverageofthesefivehighestvaluesfeachofthefourspecimens.9.1.4Calcula

33、tetheaverageofthevaluesfromthefourclosuresrepresentingthefourconfigurations.9.2Calculatetheaveragepeelfceofthesampleusingthe“Integrat”method.9.2.1Calculatetheaverageoftheintegratvaluesfromthefourclosuresrepresentingthefo

34、urdirections.9.2.2Calculatetheaverageofthevaluesfromeachofthefivesamples.9.3Ifspecimenslessthan1in.(25.4mm)widearetestedrecdtheaveragepeelfcelisttheactualwidth.10.Rept10.1Reptthefollowinginfmation:10.1.1Statethatthespeci

35、mensweretestedasdirectedinASTMTestMethodD5170.10.1.2Describethematerialproductsampled(includingtypecolsourcemanufacturer’scodepartnumber)10.1.3Thewidthofthematerialtestedwhetherthewidthwasassuppliedslitdownto1in.(25.4mm)

36、asrequiredin8.110.1.4Thecalculationmethodused:thatisaverageoffivehighestpeaksintegrataverage10.1.5Averagepeelfceperwidthofeachsampletothenearest0.1lb(.445Newtons).11.PrecisionBias11.1Precision—Basedonlimitedtestingfromon

37、elabatyusingintegrataveragesthewithinlabatyrepeatabilitystarddeviationisabout0.24lbthecoefficientofvariationisabout0.18.Repeatabilityisdependentonthespecificmaterialbeingtestedsomematerialswouldbeexpectedtobehigherlowert

38、hanthis.Betweenlabatyreproducibilityisbeingdeterminedbythesubcommittee.11.2Bias—TheprocedureinTestMethodD5170fmeasuringthepeelstrengthofhooklooptouchfastenershasnobiasbecausethevalueofthepeelstrengthofhooklooptouchfasten

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