1、Designation:D734615(Reapproved 2021)Standard Test Method forNo Flow Point and Pour Point of Petroleum Products andLiquid Fuels1This standard is issued under the fixed designation D7346;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,
2、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.Scope1.1 This test method covers the determination of the no flowpoint and pour point of petroleum products,liquid fuels
3、,biodiesel,and biodiesel blends using an automatic instrument.1.2 The measuring range of the apparatus is from 95 C to45 C,however the precision statements were derived onlyfrom samples with no flow point temperatures from 77 C to+2 C and samples with pour point in the temperature range of58 C to+12
4、 C.1.3 Pour point results from this test method can be reportedat 1 C or 3 C intervals.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated
5、with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized p
6、rinciples on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D97 Test Method for Pour Point o
7、f Petroleum ProductsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products,Liquid Fuels,and LubricantsD6708
8、Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a Material3.Terminology3.1 Definitions:3.1.1 pour point,nin petroleum products,the lowesttemperature at which movement of the test specimen isobserved under t
9、he prescribed conditions of the test.3.2 Definitions of Terms Specific to This Standard:3.2.1 no-flow point,nin petroleum products,the tempera-ture of the test specimen at which a wax crystal structureformation or viscosity increase,or both,is sufficient to impedemovement of the surface of the test
10、specimen under theconditions of the test.3.2.1.1 DiscussionThe no-flow point occurs when,uponcooling,the formation of wax crystal structures or viscosityincrease,or both,have progressed to the point where theapplied observation device no longer detects movement underthe conditions of the test.4.Summ
11、ary of Test Method4.1 After inserting the test specimen into the automatic noflow point apparatus and initiating the program,the testspecimen is heated,if necessary,to a starting temperature andthen cooled by prescribed rates.The test specimen is continu-ously tested for flow characteristics by cont
12、inuously monitor-ing the air pressure variation inside the test specimen vial.When the specimen is still fluid,its movement will partiallycompensate for the reduction in air pressure in the test chamberabove the test specimen surface.At some temperature thepressure measuring system detects a pressur
13、e decrease due toincapability of the test specimen to flow caused by a crystalstructure formation in the specimen or its viscosity increase,orboth.This temperature is recorded as no flow point with aresolution of 0.1 C.The pour point is recorded by roundingthe no flow point temperature to either the
14、 next warmer 1 C1This 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 1,2021.Published May 2021.Originallyapproved in 2007.Last previo
15、us edition approved in 2015 as D7346 15.DOI:10.1520/D7346-15R21.2For 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.Co
16、pyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1interval or 3 C interval.The test specimen is then reheated toallow for removal