ASTM_D_1267_-_12.pdf

Designation:D126712Standard Test Method forGage Vapor Pressure of Liquefied Petroleum(LP)Gases(LP-Gas Method)1This standard is issued under the fixed designation D1267;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the determination of the gagevaporpressuresofliquefiedpetroleumgasproducts(WarningFlammable gas.Harmful when inhaled.)at tem-peratures of 37.8C(100F)up to and including a testtemperature of 70C(158F).1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specificwarning statements,see 1.1 and Annex A2.2.Referenced Documents2.1 ASTM Standards:2D323 Test Method for Vapor Pressure of Petroleum Products(Reid Method)D1265 Practice for Sampling Liquefied Petroleum(LP)Gases,Manual Method3.Terminology3.1 Definitions:3.1.1 liquefied petroleum gases,nnarrow boiling rangehydrocarbon mixtures consisting mainly of propane orpropylene,or both,and butanes or butylenes,or both,pluslimited amounts of other hydrocarbons and naturally occurringnon-hydrocarbons.3.1.2 vapor pressure,nthe pressure exerted by the vaporof a liquid when in equilibrium with the liquid.4.Summary of Test Method4.1 The test apparatus,consisting of two interconnectedchambers and equipped with a suitable pressure gage,is purgedwith a portion of the sample which is then discarded.Theapparatus is then filled completely with the portion of thesample to be tested.Thirty-three and one-third to forty volumepercent of the sample content of the apparatus is immediatelywithdrawn to provide adequate free space for product expan-sion.The apparatus is then immersed in a water bath main-tained at the standard test temperature of 37.8C(100F)or,optionally,at some higher test temperature up to and includinga test temperature of 70C(158F).4.2 The observed gage pressure at equilibrium,after cor-recting for gage error and correcting to a standard barometricpressure,is reported as the LPG Vapor Pressure at the selectedtest temperature.5.Significance and Use5.1 Information on the vapor pressures of liquefied petro-leum gas products under temperature conditions from 37.8 to70C(100 to 158F)is pertinent to selection of properlydesigned storage vessels,shipping containers,and customerutilization equipment to ensure safe handling of these products.5.2 Determination of the vapor pressure of liquefied petro-leum gas is important for safety reasons to ensure that themaximum operating design pressures of storage,handling,andfuel systems will not be exceeded under normal operatingtemperature conditions.5.3 For liquefied petroleum gases,vapor pressure is anindirect measure of the most extreme low temperature condi-tions under which initial vaporization can be expected to occur.It can be considered a semi-quantitative measure of the amountof the most volatile material present in the product.6.Apparatus6.1 Vapor Pressure Apparatus,constructed as illustrated inFig.A1.1,and the various items of auxiliary equipment,arecompletely described in Annex A1.6.2 The vapor chamber of Test Method D323,can beinterchangeable with the upper chamber of this method.Similarly,the liquid chamber(two-opening type)of Test1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.H0 on Liquefied Petroleum Gas.Current edition approved Nov.1,2012.Published February 2013.Originallyapproved in 1953.Last previous edition approved in 2007 as D126702(2007).DOI:10.1520/D1267-12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Method D323 is interchangeable with the B,20%lowerchamberA1.1.4ofthismethod.Becauseofthisinterchangeability,the apparatus assembly of Test MethodD323 shall pass,as a safety precaution,the hydrostatic testspecified in A1.1.6 before using it in testing liquefied petro-leum gas.6.3 Water Bath,temperature controlled,of a size suitable forthe vapor pressure apparatus.See A1.3.6.4 Temperature Measuring Device,of verified accuracyand capable of monitoring the desired test temperature in thewater bath in the range of 35 to