1、Designation: D613 10aDesignation: 41/2000Standard Test Method forCetane Number of Diesel Fuel Oil1This standard is issued under the fixed designation D613; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method covers the determination of the ra
3、tingof diesel fuel oil in terms of an arbitrary scale of cetanenumbers using a standard single cylinder, four-stroke cycle,variable compression ratio, indirect injected diesel engine.1.2 The cetane number scale covers the range from zero (0)to 100, but typical testing is in the range of 30 to 65 cet
4、anenumber.1.3 The values for operating conditions are stated in SI unitsand are to be regarded as the standard. The values given inparentheses are the historical inch-pound units for informationonly. In addition, the engine measurements continue to be ininch-pound units because of the extensive and
5、expensivetooling that has been created for these units.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 determine the applica-bility
6、 of regulatory limitations prior to use. For more specificwarning statements, see Annex A1.2. Referenced Documents2.1 ASTM Standards:2D975 Specification for Diesel Fuel OilsD1193 Specification for Reagent WaterD2500 Test Method for Cloud Point of Petroleum ProductsD4057 Practice for Manual Sampling
7、of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsE456 Terminology Relating to Quality and StatisticsE542 Practice for Calibration of Laboratory VolumetricApparatusE832 S
8、pecification for Laboratory Filter Papers3. Terminology3.1 Definitions:3.1.1 accepted reference value (ARV), na value thatserves as an agreed-upon reference for comparison, and whichis derived as: (1) a theoretical or established value, based onscientific principles, or (2) an assigned or certified
9、value, basedon experimental work of some national or international orga-nization, or (3) a consensus or certified value, based oncollaborative experimental work under the auspices of ascientific or engineering group. E4563.1.1.1 DiscussionIn the context of this test method,accepted reference value i
10、s understood to apply to the cetanenumber of specific reference materials determined empiricallyunder reproducibility conditions by the National ExchangeGroup or another recognized exchange testing organization.3.1.2 cetane number (CN), na measure of the ignitionperformance of a diesel fuel oil obta
11、ined by comparing it toreference fuels in a standardized engine test. D41753.1.2.1 DiscussionIn the context of this test method,ignition performance is understood to mean the ignition delayof the fuel as determined in a standard test engine undercontrolled conditions of fuel flow rate, injection tim
12、ing andcompression ratio.3.1.3 compression ratio (CR), nthe ratio of the volume ofthe combustion chamber including the precombustion chamberwith the piston at bottom dead center to the comparable volumewith the piston at top dead center.1This test method is under the jurisdiction of ASTM Committee D
13、02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.01 on Combustion Characteristics.Current edition approved Oct. 1, 2010. Published November 2010. Originallyapproved in 1941. Last previous edition approved in 2010 as D61310. DOI:10.1520/D0613-10A.2For referen
14、ced 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.1*A Summary of Changes section appears at the end of this standard.Copyri
15、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.4 ignition delay, nthat period of time, expressed indegrees of crank angle rotation, between the start of fuelinjection and the start of combustion.3.1.5 injection timing (injection advanc
16、e), nthat time inthe combustion cycle, measured in degrees of crank angle, atwhich fuel injection into the combustion chamber is initiated.3.1.6 repeatability conditions, nconditions where inde-pendent test results are obtained with the same method onidentical test items in the same laboratory by th
17、e same operatorusing the same equipment within short intervals of time.E4563.1.6.1 DiscussionIn the context of this test method, ashort time interval between two ratings on a sample fuel isunderstood to be not less than the time to obtain at least onerating on another sample fuel between them but no
18、t so long asto permit any significant change in the sample fuel, testequipment, or environment.3.1.7 reproducibility conditions, nconditions where testresults are obtained with the same method on identical testitems in different laboratories with different operators usingdifferent equipment. E4563.2
19、 Definitions of Terms Specific to This Standard:3.2.1 cetane meter (ignition delay meter), nthe electronicinstrument which displays injection advance and ignition delayderived from input pulses of multiple transducers (pickups).3.2.2 Check Fuels, nfor quality control testing, a dieselfuel oil of sel
20、ected characteristics having a cetane numberaccepted reference value determined by round-robin testingunder reproducibility conditions.3.2.3 combustion pickup, npressure transducer exposed tocylinder pressure to indicate the start of combustion.3.2.4 handwheel reading, nan arbitrary numerical value,
21、related to compression ratio, obtained from a micrometer scalethat indicates the position of the variable compression plug inthe precombustion chamber of the engine.3.2.5 injector opening pressure, nthe fuel pressure thatovercomes the resistance of the spring which normally holdsthe nozzle pintle cl
22、osed, and thus forces the pintle to lift andrelease an injection spray from the nozzle.3.2.6 injector pickup, ntransducer to detect motion of theinjector pintle, thereby indicating the beginning of injection.3.2.7 primary reference fuels (PRF), nn-cetane, heptam-ethyl nonane (HMN) and volumetrically
23、 proportioned mixturesof these materials which now define the cetane number scale bythe relationship:Cetane Number 5 % n2cetane 1 0.15 % HMN! (1)3.2.7.1 DiscussionIn the context of this test method, thearbitrary cetane number scale was originally defined as thevolume percent of n-cetane in a blend w
24、ith alpha-methylnaphthalene (AMN) where n-cetane had an assignedvalue of 100 and AMN an assigned value of zero (0). A changefrom alpha-methylnaphthalene to heptamethylnonane as thelow cetane ingredient was made in 1962 to utilize a material ofbetter storage stability and availability. Heptamethylnon
25、anewas determined to have a cetane number accepted referencevalue (CNARV) of 15 based on engine testing by the ASTMDiesel National Exchange Group, using blends of n-cetane andAMN as primary reference fuels.3.2.7.2 DiscussionIn the context of this test method, theDiesel National Exchange Group of Sub
26、committee D02.013iscomposed of petroleum industry, governmental, and indepen-dent laboratories. It conducts regular monthly exchange sampleanalyses to generate precision data for this engine test standardand determines the CNARVof reference materials used by alllaboratories.3.2.8 reference pickups,
27、ntransducer(s) mounted over theflywheel of the engine, triggered by a flywheel indicator, usedto establish a top-dead-center (tdc) reference and a time basefor calibration of the ignition delay meter.3.2.9 secondary reference fuels (SRF), nvolumetricallyproportioned blends of two selected, numbered,
28、 and pairedhydrocarbon mixtures designated T Fuel (high cetane) and UFuel (low cetane) that have been rated by the ASTM DieselNational Exchange Group using primary reference fuels todetermine a cetane number accepted reference value for eachindividually and for various combinations of the two.3.3 Ab
29、breviations:3.3.1 ABDCafter bottom dead center3.3.2 AMNalpha-methylnaphthalene3.3.3 ARVaccepted reference value3.3.4 ATDCafter top dead center3.3.5 BBDCbefore bottom dead center3.3.6 BTDCbefore top dead center3.3.7 CNcetane number3.3.8 CRcompression ratio3.3.9 HMNheptamethyl nonane3.3.10 HRFhigh ref
30、erence fuel3.3.11 HWhand wheel3.3.12 IATintake air temperature3.3.13 LRFlow reference fuel3.3.14 NEGNational Exchange Group3.3.15 PRFprimary reference fuels3.3.16 SRFsecondary reference fuels3.3.17 TDCtop dead center3.3.18 UVultraviolet4. Summary of Test Method4.1 The cetane number of a diesel fuel
31、oil is determined bycomparing its combustion characteristics in a test engine withthose for blends of reference fuels of known cetane numberunder standard operating conditions. This is accomplishedusing the bracketing handwheel procedure which varies thecompression ratio (handwheel reading) for the
32、sample and eachof two bracketing reference fuels to obtain a specific ignitiondelay permitting interpolation of cetane number in terms ofhandwheel reading.5. Significance and Use5.1 The cetane number provides a measure of the ignitioncharacteristics of diesel fuel oil in compression ignition en-gine
33、s.3Bylaws governing ASTM Subcommittee D02.01 on Combustion Characteris-tics are available from the subcommittee or from ASTM International.D613 10a25.2 This test method is used by engine manufacturers,petroleum refiners and marketers, and in commerce as aprimary specification measurement related to
34、matching of fuelsand engines.5.3 Cetane number is determined at constant speed in aprecombustion chamber type compression ignition test engine.The relationship of test engine performance to full scale,variable speed, variable load engines is not completely under-stood.5.4 This test method may be use
35、d for unconventional fuelssuch as synthetics, vegetable oils, and the like. However, therelationship to the performance of such materials in full scaleengines is not completely understood.6. Interferences6.1 (WarningAvoid exposure of sample fuels and refer-ence fuels to sunlight or fluorescent lamp
36、UV emissions tominimize induced chemical reactions that can affect cetanenumber ratings.)46.1.1 Exposure of these fuels to UV wavelengths shorterthan 550 nm for a short period of time may significantly affectcetane number ratings.6.2 Certain gases and fumes present in the area where thecetane test e
37、ngine is located may have a measurable effect onthe cetane number test result.6.3 This test method is not suitable for rating diesel fuel oilswith fluid properties that interfere with unimpeded gravity flowof fuel to the fuel pump or delivery through the injector nozzle.7. Apparatus7.1 Engine Equipm
38、ent5,6This test method uses a singlecylinder engine which consists of a standard crankcase withfuel pump assembly, a cylinder with separate head assembly ofthe precombustion type, thermal syphon recirculating jacketcoolant system, multiple fuel tank system with selector valv-ing, injector assembly w
39、ith specific injector nozzle, electricalcontrols, and a suitable exhaust pipe. The engine is beltconnected to a special electric power-absorption motor whichacts as a motor driver to start the engine and as a means toabsorb power at constant speed when combustion is occurring(engine firing). See Fig
40、. 1 and Table 1.7.2 Instrumentation5,6This test method uses an electronicinstrument to measure injection and ignition delay timing aswell as conventional thermometry, gages and general purposemeters.7.2.1 Cetane Meter, (Ignition Delay Meter) is critical andshall be used for this test method.7.3 Refe
41、rence Fuel Dispensing EquipmentThis testmethod requires repeated blending of two secondary referencefuel materials in volumetric proportions on an as-needed basis.Measurement shall be performed accurately because ratingerror is proportional to blending error.7.3.1 Volumetric Blending of Reference Fu
42、elsVolumetricblending has historically been employed to prepare the re-quired blends of reference fuels. For volumetric blending, a setof two burets or accurate volumetric ware shall be used and thedesired batch quantity shall be collected in an appropriatecontainer and thoroughly mixed before being
43、 introduced to theengine fuel system.7.3.1.1 Calibrated burets or volumetric ware having a ca-pacity of 400 or 500 mL and a maximum volumetric toleranceof 60.2 % shall be used. Calibration shall be verified inaccordance with Practice E542.7.3.1.2 Calibrated burets shall be outfitted with a dispensin
44、gvalve and delivery tip to accurately control dispensed volume.The delivery tip shall be of such size and design that shutoff tipdischarge does not exceed 0.5 mL.7.3.1.3 The rate of delivery from the dispensing systemshall not exceed 500 mL per 60 s.7.3.1.4 The set of burets for the reference and st
45、andardiza-tion fuels shall be installed in such a manner and be suppliedwith fluids such that all components of each batch or blend aredispensed at the same temperature.7.3.1.5 See Appendix X1, Volumetric Reference FuelBlending Apparatus and Procedures, for typical dispensingsystem information.7.3.2
46、 Gravimetric Blending of Reference FuelsUse ofblending systems that allow preparation of the volumetrically-defined blends by gravimetric (mass) measurements based onthe density of the individual components is also permitted,provided the system meets the requirement for maximum0.2 % blending toleran
47、ce limits.7.3.2.1 Calculate the mass equivalents of thevolumetrically-defined blend components from the densities ofthe individual components at 15.56C (60F).7.4 Auxiliary Apparatus:7.4.1 Injector Nozzle TesterThe injector nozzle assemblyshall be checked whenever the injector nozzle is removed andre
48、assembled to ensure the initial pressure at which fuel isdischarged from the nozzle is properly set. It is also importantto inspect the type of spray pattern. Commercial injector nozzletesters which include a lever-operated pressure cylinder, fuelreservoir and pressure gauge are available from sever
49、al sourcesas common diesel engine maintenance equipment.7.4.2 Special Maintenance ToolsA number of specialtytools and measuring instruments should be utilized for easy,convenient and effective maintenance of the engine and testingequipment. Lists and descriptions of these tools and instru-ments are available from the manufacturers of the engineequipment and those organizations offering engineering andservice support for this test method.8. Reagents and Reference Materials8.1 Cylinder Jacket CoolantWater shall be used in thecylinder j
