ASTM_D_7668_-_14a.pdf

Designation:D766814aStandard Test Method forDetermination of Derived Cetane Number(DCN)of DieselFuel OilsIgnition Delay and Combustion Delay Using aConstant Volume Combustion Chamber Method1This standard is issued under the fixed designation D7668;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 quantitative determinationof the derived cetane number of conventional diesel fuel oils,diesel fuel oils containing cetane number improver additives,and is applicable to products typical of Specification D975,Grades No.1-D and 2-D regular,low and ultra-low-sulfurdiesel fuel oils,European standard EN590,and Canadianstandards CAN/CGSB-3.517 and CAN/CGSB3.6.The testmethod may be applied to the quantitative determination of thederived cetane number of biodiesel,blends of diesel fuel oilscontaining biodiesel material(for example,SpecificationsD975,D6751,and D7467),and diesel fuel oil blendingcomponents.1.2 This test method utilizes a constant volume combustionchamber with direct fuel injection into heated,compressedsynthetic air.A dynamic pressure wave is produced from thecombustion of the sample.An equation converts the ignitiondelay and the combustion delay determined from the dynamicpressure curve to a derived cetane number(DCN).1.3 This test method covers the ignition delay ranging from1.9 to 25 ms and combustion delay ranging from 2.5 to 160 ms(30 to 70 DCN).However,the precision stated only covers therange of DCN from 39 to 67.1.4 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 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.2.Referenced Documents2.1 ASTM Standards:2D613 Test Method for Cetane Number of Diesel Fuel OilD975 Specification for Diesel Fuel OilsD1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum,PetroleumProducts,and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD5854 Practice for Mixing and Handling of Liquid Samplesof Petroleum and Petroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a MaterialD6751 Specification for Biodiesel Fuel Blend Stock(B100)for Middle Distillate FuelsD7467 Specification for Diesel Fuel Oil,Biodiesel Blend(B6 to B20)E456 Terminology Relating to Quality and Statistics2.2 EN Standards:3EN590 Automotive FuelsDieselRequirements and TestMethods2.3 Energy Institute Standards:4IP41 Ignition Quality of Diesel FuelsCetane Engine TestMethod1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.01.0C on Test Equipment,Procedures,and Instrumentation.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 2010.Last previous edition approved in 2014 as D7668 14.DOI:10.1520/D7668-14A.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 European Committee for Standardization.Central Secretariat:rue de Stassart,36,B-1050 Brussels,Belgium.4Available from Energy Institute,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 2.4 Canadian Standards:5CAN/CGSB-3.517 RegularSulphurDieselFuelSpecificationCAN/CGSB 3.6 Automotive Low-Sulphur Diesel FuelSpecification2.5 DIN Standards:6DIN 73372 Einspritzdsen Grsse T und U3.Terminology3.1 Definitions:3.1.1 accepted reference value(ARV),na value that servesas an agreed-upon reference for comparison and that is derivedas(1)a theoretical or established value,based on scientificprinciples,(2)an assigned value,based on experimental workof some national or international organization,such as the U.S.National Institute of Standards and Technology(NIST),or(3)a consensus value,based o