1、Designation: D 613 08Designation: 41/2000An American National StandardStandard Test Method forCetane Number of Diesel Fuel Oil1This standard is issued under the fixed designation D 613; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method cove
3、rs the determination of the ratingof 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 i
4、s in the range of 30 to 65 cetanenumber.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
5、 because of the extensive and 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 an
6、d determine the applica-bility of regulatory limitations prior to use. For more specificwarning statements, see Annex A1.2. Referenced Documents2.1 ASTM Standards:2D 975 Specification for Diesel Fuel OilsD 1193 Specification for Reagent WaterD 2500 Test Method for Cloud Point of Petroleum ProductsD
7、4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD 4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsE 456 Terminology Relating to Quality and StatisticsE 542 Practice for Calibration o
8、f Laboratory VolumetricApparatusE 832 Specification 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 princ
9、iples, or (2) an assigned or certified 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. E 4563.1.1.1 DiscussionIn the context of thi
10、s test method,accepted reference value is 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 ignit
11、ionperformance of a diesel fuel oil obtained by comparing it toreference fuels in a standardized engine test. D 41753.1.2.1 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 co
12、nditions of fuel flow rate, injection timing 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.3.1.4 ignition delay,
13、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 advance), nthat time inthe combustion cycle, measured in degrees of crank angle, atwhich fuel injection into the combustion chamber is i
14、nitiated.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.01 on Combustion Characteristics.Current edition approved Sept. 1, 2008. Published October 2008. Originallyapproved in 1941. Last previou
15、s edition approved in 2005 as D 61305.2For 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.1*A Summary of Changes
16、section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.6 repeatability conditions, nconditions where inde-pendent test results are obtained with the same method onidentical test items in the sa
17、me laboratory by the same operatorusing the same equipment within short intervals of time.E 4563.1.6.1 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
18、 between them but not 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 usingdifferen
19、t equipment. E 4563.2 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
20、dieselfuel oil of selected 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 arbit
21、rary numerical value,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 hold
22、sthe nozzle pintle closed, 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 (HM
23、N) and volumetrically 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
24、n-cetane in a blend with 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 availab
25、ility. Heptamethylnonanewas 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
26、Exchange Group of Subcommittee 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.
27、8 reference pickups, 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 tw
28、o selected, numbered, 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 combinati
29、ons of the two.3.3 Abbreviations: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 non
30、ane3.3.10 HRFhigh reference 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 num
31、ber of a diesel fuel 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 (handwh
32、eel reading) for the 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 compres
33、sion ignition en-gines.5.2 This test method is used by engine manufacturers,petroleum refiners and marketers, and in commerce as aprimary specification measurement related to matching of fuelsand engines.3Bylaws governing ASTM Subcommittee D02.01 on Combustion Characteris-tics are available from the
34、 subcommittee or from ASTM International.D6130825.3 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 tes
35、t method may be used 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 o
36、r fluorescent lamp 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 whe
37、re thecetane test engine 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. Apparat
38、us7.1 Engine Equipment5,6This 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,
39、injector assembly with 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(engi
40、ne firing). See Fig. 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 t
41、est method.7.3 Reference 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 Blend
42、ing of Reference FuelsVolumetricblending 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
43、 mixed before being 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 E 542.7.3.1.2 Calibrated burets shall be outfit
44、ted with a dispensingvalve 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
45、the reference and standardiza-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 dispensingsyst
46、em information.7.3.2 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.
47、2 % blending tolerance 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 noz
48、zle is removed andreassembled 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
49、available from several 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 us
