ASTM_D_7153_-_15.pdf

Designation:D715315IP 52915Standard Test Method forFreezing Point of Aviation Fuels(Automatic Laser Method)1This standard is issued under the fixed designation D7153;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 tem-perature below which solid hydrocarbon crystals may form inaviation turbine fuels.1.2 This test method is designed to cover the temperaturerange of 80 C to 20 C;however,the interlaboratory studymentioned in 12.4 has only demonstrated the test method withfuels having freezing points in the range of 60 C to 42 C.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 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 to determine theapplicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D2386 Test Method for Freezing Point of Aviation FuelsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum Products2.2Energy Institute Standard:IP 16 Determination Freezing Point of Aviation Fuels33.Terminology3.1 Definitions:3.1.1 freezing point,nin aviation fuels,the fuel tempera-ture at which solid hydrocarbon crystals,formed on cooling,disappear when the temperature of the fuel is allowed to riseunder specified conditions of test.3.2 Definitions of Terms Specific to This Standard:3.2.1 automatic laser method,nthe procedures of auto-matically cooling a liquid aviation fuel specimen until solidhydrocarbon crystals appear,followed by controlled warmingand recording of temperature at which hydrocarbon crystalscompletely redissolve into the liquid phase.3.3 Symbols:Cd=the specimen temperature at which the appearance ofthe first crystals are detected in the specimen by anoptical crystal detector under specified conditions oftest.Co=the specimen temperature at which the appearance ofopacity in the specimen is detected by an opticalopacity detector under specified conditions of test.Do=the specimen temperature at which the disappearanceof opacity in the specimen is detected by an opticalopacity detector under specified conditions of test.4.Summary of Test Method4.1 Aspecimen is cooled at a rate of 10 C min 6 5 C minwhile continuously being illuminated by a laser light source.The specimen is continuously monitored by optical crystal andopacity detectors for the first formation of solid hydrocarboncrystals.Once the hydrocarbon crystals are detected by bothsets of optical detectors,the specimen is then warmed at a rateof 3 C min 6 0.5 C min.When initial opacity in thespecimen disappears,the specimen is then warmed at a rate of12 C min 6 l C min.The specimen temperature at whichthe last hydrocarbon crystals return to the liquid phase,asdetected by the crystal detector,is recorded as the freezingpoint.4.2 In certain circumstances,as measured by the apparatus,the specimen is reheated to approximately 10 C,then cooledat the rate in 4.1 until hydrocarbon crystals are detected by thecrystal detector.The specimen is then warmed at a rate of12 C min 6 l C min,until the last hydrocarbon crystalsreturn to the liquid phase.The specimen temperature at which1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.07 on Flow Properties.Current edition approved April 1,2015.Published April 2015.Originallyapproved in 2005.Last previous edition approved in 2010 as D7153 05(2010).DOI:10.1520/D7153-15.2For 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.3Annual Book of IP Standards Methods,Vol 1.Available from Energy Institute,61 New Cavendish St.,London,WIG 7AR,U.K.*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 the last hydrocarbon crystals return to the liquid phase,asdetected by the crystal detector,is recorded as the freezingpoint.5.Significance and Use5.1 The freezing point of an aviation fuel is the lowesttemperature at which the fuel remains free of solid hydrocar-bon crystals which,if present in the fuel system of the aircraft,can restrict the flow of fuel through filters.The temperature ofthe fuel in the aircraft tank normally decreases during flightdepending on aircraft spee