ASTMD323-99a

Designation:D 323-99aAn American Nafional StandardNTERNATIONALStandard Test Method forVapor Pressure of Petroleum Products (Reid Method)1This standard is issued under the fixed designation D323;the number immediately following the designation indicates the year oforiginal adoption or,in the caseof revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon (e)indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scopeleum (LP)Gases (LP-Gas Method)21.1 This test method covers procedures for the determina-D 4057 Practice for Manual Sampling of Petroleum andtion of vapor pressure (see Note 1)of gasoline,volatile crudePetroleum Products3oil,and other volatile petroleum products.Procedure A isD 4953 Test Method for Vapor Pressure of Gasoline andapplicable to gasoline and other petroleum products with aGasoline-Oxygenate Blends(Dry Method)3vapor pressure of less than 180 kPa(26 psi).Procedure B mayE 1 Specifi cation for ASTM Thermometersalso be applicable to these other materials,but only gasolinewas included in the interlaboratory test program to determine3.Summary of Test Methodthe precision of this test method.Neither procedure is appli-3.1 The liquid chamber of the vapor pressure apparatus iscable to liquefi ed petroleum gases or fuels containing oxygen-filled with the chilled sample and connected to the vaporated compounds other than methyl -butyl ether (MTBE)(seechamber that has been heated to 37.8C(100F)in a bath.TheNote 2).Procedure C is for materials with a vapor pressure ofassembled apparatus is immersed in a bath at 37.8C(100F)greater than 180 kPa (26 psi)and Procedure D for aviationuntil a constant pressure is observed.The reading,suitablygasoline with a vapor pressure of approximately 50 kPa(7 psi).corrected,is reported as the Reid vapor pressure.3.2 All four procedures utilize liquid and vapor chambers ofNorE 1-Because the external atmospheric pressure is counteracted bythe same intemal volume.Procedure B utilizes a semi-the atmospheric pressure initially present in the vapor chamber,the Reidvapor pressure is an absolute pressure at 37.8C(100F)in kilopascalsautomatic apparatus immersed in a horizontal bath and rotated(pounds-force per square inch).The Reid vapor pressure differs from thewhile attaining equilibrium.Either a Bourdon gage or pressuretrue vapor pressure of the sample due to some small sample vaporizationtransducer may be used with this procedure.Procedure Cand the presence of water vapor and air in the confi ned space.utilizes a liquid chamber with two valved openings.ProcedureNoTE 2-For determination ofthe vapor pressure ofliquifi ed petroleumD requires more stringent limits on the ratio of the liquid andgases refer to Test Method D 1267.For determination of the vaporvapor chambers.pressure of gasoline-oxygenate blends refer to Test Method D 4953.1.2 The values stated in S