MIL-STD-202-211-2020美国美军标准

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INCH-POUNDMIL-STD-202-211w/CHANGE1

15December2020

SUPERSEDINGMIL-STD-202-211

18April2015

DEPARTMENTOFDEFENSETESTMETHODSTANDARD

METHOD211,TERMINALSTRENGTH

AMSCN/A FSC59GP

MIL-STD-202-211w/CHANGE1

FOREWORD

ThisstandardisapprovedforusebyallDepartmentsandAgenciesoftheDepartmentofDefense.

Thisentirestandardhasbeenrevised.Thisrevisionhasresultedinmanychangestotheformat,butthemostsignificantoneisthesplittingthedocumentintotestmethods.SeeMIL-STD-202forthechangesummary.

Comments,suggestions,orquestionsonthisdocumentshouldbeemailedto

std202@

oraddressedto:Commander,DefenseLogisticsAgency,DLALandandMaritime,ATTN:VAT,P.O.Box3990,Columbus,OH43218–3990.Sincecontactinformationcanchange,youmaywanttoverifythecurrencyofthisaddressinformationusingtheASSISTOnlinedatabaseat

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SUMMARYOFCHANGE1MODIFICATIONS

1.ModifiedContentsFigure5TestConditionto“E”.

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CONTENTS

PARAGRAPH PAGE

FOREWORD…………. ii

SCOPE 1

1.1 Purpose………….……..…………. 1

APPLICABLEDOCUMENTS 1

DEFINITIONS 1

GENERALREQUIREMENTS 1

4.1 Testconditions..………………….…...………….1

4.1.1 Selection………….1

4.2. Procedure……..……………….….2

4.2.1 TestconditionA(pulltest)………..………….….2Methodofholding…..………….…………..…….2Appliedforce..….…………..…….2

Directionofappliedforce….………………….2

Durationofappliedforce.…….2

4.2.2 TestconditionB(flat-terminalbendtest)….2

Startingpositionofterminal……………….…………….………2

Bendingcycle…………….………2

Numberofbendingoperations……….…………2

4.2.3 TestconditionC(wire-leadbendtest)……………….…………2

Preparationofspecimen………….…………..…2

Bendingcycle…………….………2

Numberofbendingoperations……….…………2

4.2.4 TestconditionD(twisttest).………….…………2

Preparationofspecimen………….…………..…2

Applicationoftorsion……….…………..……..…3

4.2.5 TestconditionE(torquetest)………….……………..……..…3

Directionandapplicationoftorque….………………..……..…3

Durationofappliedforce.…….………..……..…3

Screw-threadterminals……………….………..……………..…3

Othernon-wire,rigid-typeterminals….…………..………….…3

DETAILEDREQUIREMENTS 7

5.1 Measurements……..…..…………. 7

5.2. Summary………. 7

NOTES 7

6.1 Supersessiondata………………. 7

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CONTENTS(continued)

FIGURE PAGE

1.TestconditionA…………..… 3

2.TestconditionB…………..… 4

3.TestconditionC…………..… 4

4.TestconditionD…………..… 5

5.TestconditionE…………..… 6

6.Methodofdeterminingequivalentdiameter….………..… 6

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SCOPE

METHOD211TERMINALSTRENGTH

1.1Purpose.Thistestisperformedtodeterminewhetherthedesignoftheterminalsandtheirmethodofattachmentcanwithstandoneormoreoftheapplicablemechanicalstressestowhichtheywillbesubjectedduringinstallationordisassemblyinequipment.Thesestressesmustbewithstoodbythecomponentpartwithoutsustainingdamagewhichwouldaffecteithertheutilityoftheterminalsortheoperationofthecomponentpartitself.Evidenceofdamagecausedbythistestmaynotbecomeevidentuntilsubsequentenvironmentaltestsareperformed,suchasseal,moistureresistance,orlife.Proceduresareestablishedinthismethodfortestingwire-leadterminals,flexible-flat-striportab-leadterminals,andrigid-typeterminalswhicharethreadedorhaveotherarrangementsforattachingconductors.Theforcesappliedconsistofdirectaxial,radialortensionpulls,twist,bendingtorsion,andthetorqueexertedbytheapplicationofnutsorscrewsonthreadedterminals.Theseappliedstresseswilldisclosepoorworkmanship,faultydesigns,andinadequatemethodsofattachingterminalstothebodyofthepart.Otherevidenceofdamagemaybedisclosedbymechanicaldistortionofthepart,breakingofseals,crackingofmaterialssurroundingtheterminals,orchangesinelectricalcharacteristics,suchasshortedorinterruptedcircuitsandchangesinresistancevalues.

APPLICABLEDOCUMENTS

Thissectionisnotapplicabletothisstandard.

DEFINITIONS

Thissectionnotapplicabletothisstandard.

GENERALREQUIREMENTS

Testconditions.

Selection.Inthismethodtherearefivetestconditions,A,B,C,D,andE.Theselectionoftestconditionstoperformtheterminal-strengthtestdependsonthetypeofterminaltobetested.Theindividualspecificationshallspecifythetestconditionrequired.Thefollowingisincludedasaguidetobeused,asapplicable:

TestconditionA: Pulltest-alsoknownasatensionortensiletestforterminals.Itisusuallyapplicabletomosttypesofterminals.

TestconditionB: Flat-terminalbendtest-alsoknownasabendtest.Itisapplicabletoflexible-flat-striportab-leadterminalswhichcanbebentbyfingerpressure.

TestconditionC: Wire-leadbendtest-alsoknownasalead-fatigue,bend,orflexibilitytest.Itisapplicabletosolid-wire-leadterminalsoflimitedductility,suchasnickel-alloy-typeleadsandthoseusedinhermetically-sealedcomponentparts.

TestconditionD: Twisttest-alsoknownasatorsiontest.Itisusuallyapplicabletoductile,solid-wire-leadterminalsintendedforwraparoundconnections.

TestconditionE: Torquetest-Itisapplicabletorigid-typeterminalshavingeitherexternalscrewthreadsorthreadedinsertswhicharelocatedatthecenteroftheterminal,ortoothernon-wire,rigid-typeterminalswhichshouldwithstandtheturningmomentthatresultsfromaforceappliedfromanoff-centerpointontheterminal.

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Procedure.Oneormoreofthefollowingtestconditionlettersshallbespecifiedintheindividualspecification:

TestconditionA(pulltest).

Methodofholding.Ifthemethodofholdingorclampingispertinent,itshallbespecifiedintheindividualspecification.

Appliedforce.Theforceappliedtotheterminalshallbe1/2,1,2,3,5,10,or20pounds,asspecifiedintheindividualspecification.

Directionofappliedforce.Thepointofapplicationoftheforceandtheforceappliedshallbeinthedirectionoftheaxesoftheterminations,asshownonfigure1.

Durationofappliedforce.Theforceshallbeappliedgraduallytotheterminalandthenmaintainedforaperiodof5to10seconds.

TestconditionB(flat-terminalbendtest).

Startingpositionofterminal.Priortothetest,theterminalshallbeobservedtodetermineifitisorientedinitsnormalorunbentposition,orifitispermanentlybentoutofposition,ascouldoccurasaresultofpriortesting.

Bendingcycle.Ifthemethodofbendingisnotcritical,theterminalsmaybebentbyfingerpressurethroughabendingcycleofthreebends,asshownonfigure2.Thebendingcycleshallstartwitha45bendtoonesideofthenormalposition.Iftheterminalisalreadybenttoananglebetween0and45toonesideofthenormalpositionpriortotest,itshallbebentinthesamedirectionuntilanangleof45isachieved.Theterminalshallthenbebent90intheoppositedirectiontoapoint45ontheoppositesideofthenormalposition,andthenback45tonormal.Ifthemethodofbendingiscritical,theindividualspecificationshallspecifythemethodofbendingandanyfixturerequiredtocontrolthepointofapplication.Therateofbendingshallbeapproximately3secondsperbendineachdirection.

Numberofbendingoperations.Thenumberofbendingoperationsshallbetwoorfive,asspecifiedintheindividualspecification.

TestconditionC(wire-leadbendtest).

Preparationofspecimen.Aloadof1/4,1/2,1,5,or10pounds,asspecifiedintheindividualspecification,shallbesuspendedfromtheterminal.Theloadselectedshallbethatclosestinvaluetoone-halftheloadappliedduringthepulltest.Thebodyofthecomponentpartshallbeheldwithasuitableclampingorattachingdevice,sothattheterminalisinitsnormalpositionwithrespecttothecomponentpart.Theloadshallbesuspendedatapointwithin1/4inchfromthefreeendoftheterminal.

Bendingcycle.Thebodyofthecomponentpartshallbeslowlyinclinedsoastobendtheterminalthrough90°andthenreturnittonormalposition,asshownonfigure3.Thisentireactionshallbelimitedtooneverticalplane.Abendthrough90°andreturntonormalpositionshallbedefinedasonebend.Consecutivebendsshallbeinthesamedirection.Theloadshallberestrictedsuchthatthebendstarts3/32±1/32inchfromthebodyofthecomponentpart.Therateofbendingshallbeapproximately3secondsperbendineachdirection.

Numberofbendingoperations.Thenumberofbendingoperationsshallbethree.

TestconditionD(twisttest).

Preparationofspecimen.Thesolid-wire-leadterminalshallbebent90°atapoint1/4inchfromitsjuncturewiththebodyofthecomponentpart,asshownonfigure4.Theradiusofcurvatureofthe90°bendshallbeapproximately1/32inch.Thefreeendoftheterminalshallbeclampedatapoint3/64±1/64inchawayfromthebend,asshownonfigure4.

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Applicationoftorsion.Thebodyofthecomponentpartortheclampedterminalshallberotatedthrough360°abouttheoriginalaxisofthebentterminal,inalternatingdirections,foratotalofthreerotations1080°,attherateofapproximately5secondsperrotation.

TestconditionE(torquetest).

Directionandapplicationoftorque.Thetorqueshallbeappliedclockwiseandthencounterclockwiseinaplaneperpendiculartotheaxisoftheterminal,asshownonfigure5.

Durationofappliedforce.Theforceshallbeappliedgraduallytotheterminalandthenmaintainedforaperiodof5to15seconds.

Screw-threadterminals.Whentestingscrew-threadterminals,thetorque,inaccordancewiththeterminalsize,shallbeappliedtothecenterlineoftheterminalassembly,asfollows:

Screw-thread Torqueterminals (pound-inches)

No.4 3.0

No.6 5.0

No.8 11.0

No.10 15.0

No.12 24.0

1/4inch 32.0

Othernon-wire,rigid-typeterminals.Whentestingothernon-wire,rigid-typeterminals,theappliedtorqueisdependentontheequivalentdiameteroftheexternalportionoftheterminalassembly.Theequivalentdiameterisdefinedasequaltotwicethedistancefromtheterminalaxistothepointofnormalwireconnection,asshownintheexamplesonfigure6.Thetorqueshallbeappliedinaccordancewiththeequivalentdiameter,asfollows:

Equivalentdiameter Torque(inch) (ounce-inches)

1/16orless 0

>1/16to1/8inclusive 8

>1/8to3/16inclusive 18

>3/16to5/16inclusive 40

>5/16to1/2inclusive 80

>1/2Asspecifiedintheindividualspecification

FIGURE1.TestconditionA.

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FIGURE2.TestconditionB.

FIGURE3.TestconditionC.

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STEP1.Bendleadwithfingers,overroundededgeofmetalplateasshownin(a).STEP2.Centercomponentpartinchuck;secureleadinclampasshownin(b).

STEP3.Rotatechuckpartthrough360°atarateofapproximately5secondsper360°rotation.Successiverotationsshallbeinalternatedirections.Atotalofthreesuch360°rotationsshallbeperformed.Duringthistest,thechuckshallrotatearoundanaxiswhichisfixedwithrespecttothepaddedclamp,orviceversa.Thechuckshallhavenoappreciableendplayduringrotation.

NOTES:

Dimensionsareininches.

Metricequivalentsareinparenthesesandaregivenforgeneralinformationonly.

FIGURE4.TestconditionD.

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FIGURE5.TestconditionE.

NOTE:Equivalentdiameteristwicethedistancebetweenthelinesindicatedbythearrows.

FIGURE6.Methodofdeterminingequivalentdiameter.

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DETAILEDREQUIREMENTS

Measurements.Measurementstobemadebeforeandafterthetest,asapplicable,shallbeasspecifiedintheindividualspecification.

Summary.Thefollowingdetailsaretobespecifiedintheindividualspecification:

Testconditionletter(s)(see4.2).

IftestconditionletterAisspecified:

Ifpertinent,themethodofholdingorclamping(see).

Whetherappliedforceshallbe1/2,1,2,3,5,10,or20pounds(see).

IftestconditionletterBisspecified:

Ifcritical,themethodofbendingandfixturerequired(see).

Whethernumberofbendsshallbe2or5(see