ASTMD51ö971=07595100500864.59([ThDesignation:D5189-91AMERICANSOCIETYMRTESTINGANDMATERIALS1916RaceSt.Philadelphia,Pa19103ReprintedfromtheAnnualBookofASTh4Standards.CopyrightASTMIfnotlistedinthecurrentcombinedIndex,willappearinthenextedition.StandardTestMethodforTemperatureCorrespondingtoVapor-LiquidRatioof20forGasolineandGasoline-OxygenateBlends(BombMethod)’ThisstandardisissuedunderthefixeddesignationD5189;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethod(seeNote1)coversaproceduretodeterminethetemperatureatwhichthevaporformedfromagasolineoragasoline-oxygenateblend,saturatedwithairatOto1°C(32to34”F),producesacalculatedpartialpressureequaltoIO1.3kPa(1atm).Thistestmethodisperformedwithametalfuelchamber,originallyfilledwiththechilledliquidfuel,connectedtoavaporchamber20.0timesthevolumeoftheliquidchamber.Thistemperatureisconsid-eredtobecomparabletothetemperatureatwhichthevapor-liquidratioofthefuel(seeNote2)isequalto20asdeterminedbyTestMethodD2533.Thistestmethodisnotapplicabletosampleshavingavaporpressureabove180kPa(26psi)asdeterminedbyTestMethodD323orbyTestMethodD4953.NOTEI-Thistestmethodisalsoknownasthe“BombV/LTestMethod.”KOTE2-TestMethodD2533isapplicabletogasoline-oxygenateblendsonlywhenmercuryisusedastheconfiningmedium.Subcom-mitteeD02.08iscurrentlyevaluatingthesuitabilityofD2533usingglycerolastheconfiningmediumforcertaingasoline-oxygenateblends.I.2Theactualvapor-liquidratioundertheseconditionsisnotexactly20.0sincenocorrectionsaremadefortheexpansionoftheliquidsamplewithincreasingtemperature,thedecreaseinliquidsamplevolumebecauseofpartialvaporization,thedissolvedairintheliquidsample,andtheeffectoftheairoriginallypresentinthevaporchamber.1.3Inthistestmethodthepartialpressureofthefuelisobservedasagagepressureinthepresenceofair.InTestMet...
