1、Designation:D739710Standard Test Method forCloud Point of Petroleum Products(Miniaturized OpticalMethod)1This standard is issued under the fixed designation D7397;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revis
2、ion.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 cloudpoint of petroleum products and biodiesel fuels that aretransparent in layers
3、40 mm in thickness by an automaticinstrument.1.2 This test method covers the range of temperatures from60 to+20C with temperature resolution of 0.1C;however,the range of temperatures included in the 2006 interlaboratorycooperative test program only covered the temperature range of35 to+12C.See Secti
4、on 13.1.3 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 ap
5、pro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D2500 Test Method for Cloud Point of Petroleum ProductsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Auto
6、matic Sampling of Petroleum andPetroleum ProductsD5773 Test Method for Cloud Point of Petroleum Products(Constant Cooling Rate Method)2.2 Energy Institute Standards:3IP 219 Test Method for Cloud Point of Petroleum ProductsIP 446 Test Method for Cloud Point of Petroleum Products3.Terminology3.1 Defin
7、itions:3.1.1 biodiesel,nfuel comprising mono-alkyl esters oflong-chain fatty acids derived from vegetable oils or animalfats,designated B100.3.1.1.1 DiscussionBiodiesel is typically produced by areaction of vegetable oil or animal fat with an alcohol such asmethanol or ethanol in the presence of a c
8、atalyst to yieldmono-esters and glycerin.The fuel typically may contain up to14 different types of fatty acids that are chemically transformedinto fatty acid methyl esters(FAME).3.1.2 biodiesel blend(BXX),nblend of biodiesel fuel withpetroleum-based diesel fuel designated BXX,where XX is thevolume p
9、ercentage(as a whole number without the percentagesign)of biodiesel.3.1.3 cloud point,nin petroleum products and biodieselfuels,the temperature of a liquid specimen when the smallestobservable cluster of hydrocarbon crystals first occurs uponcooling under prescribed conditions.3.1.3.1 DiscussionThe
10、cloud point occurs when the tem-perature of the specimen is low enough to cause hydrocarboncrystals to precipitate.In a homogeneous liquid,the cloud isalways noted first at the location in the specimen where thespecimen temperature is the lowest.The cloud point is thetemperature at which the crystal
11、s first occur,regardless of theirlocation in the specimen,and not after extensive crystallizationhas taken place.The hydrocarbon crystals that precipitate atlower temperatures are typically,but not excluded to,straightchain hydrocarbons commonly called“wax crystals.”3.2 Definitions of Terms Specific
12、 to This Standard:3.2.1 D2500/IP 219 equivalent cloud point,ntemperatureof a specimen,in integers,calculated by applying a bias androunding the result to the next lower integer(see 12.2).3.2.1.1 DiscussionThis test method produces results with0.1C resolution.Should the user wish to provide results w
13、itha similar format to Test Method D2500,then this calculationcan be performed(see 12.2).Some apparatus can perform thiscalculation automatically.3.2.2 automatic cloud point,ntemperature of a specimen,when the appearance of the cloud is determined under theconditions of this test method.1This test m
14、ethod 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 May 1,2010.Published August 2010.Originallyapproved in 2007.Last previous edition approved in 2008
15、 as D739708.DOI:10.1520/D7397-10.2For 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.3Available from Energy Institute,
16、61 New Cavendish St.,London,WIG 7AR,U.K.,http:/www.energyinst.org.uk.*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 3.2.2.1 DiscussionThe cloud point in this test method isdetermined by an automatic instrument using a miniaturizedtest receptacle equipped with two optical fibers,one to bringlight into the test receptacle and the other to receive lightscattered from the s
