ASTM_D_4737_-_21.pdf

Designation:D473721Standard Test Method forCalculated Cetane Index by Four Variable Equation1This standard is issued under the fixed designation D4737;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 The calculated Cetane Index by Four Variable Equationprovides a means for estimating the ASTM cetane number(Test Method D613)of distillate fuels from density anddistillation recovery temperature measurements.The valuecomputed from the equation is termed the Calculated CetaneIndex by Four Variable Equation.1.2 The Calculated Cetane Index by Four Variable Equationis not an optional method for expressingASTM cetane number.It is a supplementary tool for estimating cetane number whena result by Test Method D613 is not available and if cetaneimprover is not used.As a supplementary tool,the CalculatedCetane Index by Four Variable equation must be used with dueregard for its limitations.1.3 Procedure A is to be used for Specification D975,Grades No.1D S15,No.1D S500,No.1D S5000,No.2DS15,No.2D S5000,and No.4D.This method for estimatingcetane number was developed by Chevron Research Co.2Procedure A is based on a data set including a relatively smallnumber of No.1D fuels.Test Method D4737 Procedure Amay be less applicable to No.1D S15,No.1D S500,and No.1D S5000 than to No.2D grade S5000 or to No.4D fuels.1.3.1 Procedure A has been verified as applicable to GradeNo.2D S15 diesel fuels.31.4 Procedure B is to be used for Specification D975,GradeNo.2D S500.1.5 The test method“Calculated Cetane Index by FourVariable Equation”is particularly applicable to Grade 1DS5000,Grade No.1D S500,Grade No.2D S5000 and GradeNo.2D S500 diesel fuel oils containing straight-run andcracked stocks,and their blends.It can also be used for heavierfuels with 90%recovery points less than 382 C and for fuelscontaining derivatives from oil sands and oil shale.NOTE1Sxx is the designation for maximum sulfur level specified forthe grade.For example,S500 grades are those with a maximum sulfurlimit of 500 ppm(g/g).1.6 Biodiesel blends are excluded from this test method,because they were not part of the datasets use to develop eitherProcedure A or B.1.7 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.8 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accor-dance with internationally recognized principles 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:4D86 Test Method for Distillation of Petroleum Products andLiquid Fuels at Atmospheric PressureD613 Test Method for Cetane Number of Diesel Fuel OilD975 Specification for Diesel FuelD1298 Test Method for Density,Relative Density,or APIGravity of Crude Petroleum and Liquid Petroleum Prod-ucts by Hydrometer MethodD2887 Test Method for Boiling Range Distribution of Pe-troleum Fractions by Gas ChromatographyD4052 Test Method for Density,Relative Density,and APIGravity of Liquids by Digital Density MeterD4175 Terminology Relating to Petroleum Products,Liquid1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.E0 on Burner,Diesel and Non-Aviation Gas Turbine Fuels.Current edition approved Nov.1,2021.Published November 2021.Originallyapproved in 1987.Last previous edition approved in 2016 as D4737 10(2016).DOI:10.1520/D4737-21.2Ingham,M.C.,et al.,“Improved Predictive Equations for Cetane Number,”SAE Paper No 860250,Society of Automotive Engineers(SAE),400 Common-wealth Dr.,Warrendale,PA 15096-0001.3Supporting data(the analysis leading to the use of ProcedureAfor No.2-D S15diesel fuels and to Procedure B)have been filed at ASTM International Headquar-ters and may be obtained by requesting Research Report RR:D02-1699.ContactASTM Customer Service at serviceastm.org.4For 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 StatesThis international standard w