Designation:D5638−18StandardTestMethodforChemicalResistanceofElectricalInsulatingVarnishes1ThisstandardisissuedunderthefixeddesignationD5638;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversthemechanicalperformanceofinsulatingvarnishesafterexposuretovariouschemicals.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.See7.1.NOTE1—ThereisnoIEC/ISOequivalent.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D2519TestMethodforBondStrengthofElectricalInsulat-ingVarnishesbytheHelicalCoilTest3.Terminology3.1SeeTestMethodD2519.4.SummaryofTestMethod4.1Flexuralstrengthtestsaremadeonvarnish-treatedhelicalcoilstodeterminetheforcerequiredtobreakthecoilunderspecifiedconditionsbothbeforeandafterexposuretoliquidchemicals.5.SignificanceandUse5.1Thistestmethodisusefulfortheevaluationofinsulat-ingvarnishperformanceinchemicalexposure.6.Apparatus6.1TensileTestingMachine—SeeTestMethodD2519.6.2TestFixture—SeeTestMethodD2519.6.3ChemicalContainers—Sealable1000-mLcontainersofsuitablematerialanddesignforcontainingthechemicalstobeused.7.SafetyPrecautions7.1Itisunsafetousevarnishattemperaturesabovetheflashpointwithoutadequateventilation,especiallyifthepossibilityexiststhatflameso...
