1、Designation: D7688 18Standard Test Method forEvaluating Lubricity of Diesel Fuels by the High-FrequencyReciprocating Rig (HFRR) by Visual Observation1This standard is issued under the fixed designation D7688; the number immediately following the designation indicates the year oforiginal adoption or,
2、 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 evaluation of the lubricity ofdiesel fuels using a
3、high-frequency reciprocating rig (HFRR).1.2 This test method is applicable to middle distillate fuels,such as Grades No. 1-D S15, S500, and S5000, and Grades No.2-D S15, S500, and S5000 diesel fuels, in accordance withSpecification D975; and other similar petroleum-based fuelswhich can be used in di
4、esel engines. This test method also isapplicable to biodiesel blends. B5 was included in the roundrobin program that determined the precision statement.NOTE 1It is not known that this test method will predict theperformance of all additive/fuel combinations. Additional work is under-way to establish
5、 this correlation and future revisions of this test methodmay be necessary once this work is complete.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, i
6、f 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.Specific warning statements are given in Section 7.1.5 This international
7、 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
8、.2. Referenced Documents2.1 ASTM Standards:2D975 Specification for Diesel Fuel OilsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4306 Practice for Aviation Fuel Sample Containers forTests Affected by Trac
9、e ContaminationD6078 Test Method for Evaluating Lubricity of Diesel Fuelsby the Scuffing Load Ball-on-Cylinder Lubricity Evalua-tor (SLBOCLE)E18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE92 Test Methods for Vickers Hardness and Knoop Hard-ness of Metallic Materials2.2 SAE Standard:3S
10、AE-AMS 6440 Steel, Bars, Forgings, and Tubing, 1.45 Cr(0.93-1.05C) (SAE 52100), for Bearing Applications2.3 ISO Standard:4ISO 3290 Roller Bearings, Balls Dimensions and toler-ances3. Terminology3.1 Definitions:3.1.1 boundary lubrication, na condition in which thefriction and wear between two surface
11、s in relative motion aredetermined by the properties of the surfaces and the propertiesof the contacting fluid, other than bulk viscosity.3.1.1.1 DiscussionMetal to metal contact occurs and thechemistry of the system is involved. Physically adsorbed or1This test method is under the jurisdiction of A
12、STM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.E0 on Burner, Diesel, Non-Aviation Gas Turbine, and MarineFuels.Current edition approved Aug. 1, 2018. Published September 2018. Originallypublished in 2011. Last previous edition
13、 approved in 2016 as D7688 11 (2016).DOI: 10.1520/D7688-18.This test method was developed by ISO/TC22/SC7/WG6 and is a part of ISO12156.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume in
14、formation, refer to the standards Document Summary page onthe ASTM website.3Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale,PA 15096-0001, http:/www.sae.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.
15、ansi.org.*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 was developed in accordance with internationally recognized principles on standardiza
16、tion 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.1chemically reacted soft films (usually very thin) supportcontact loads. As a result, some wear
17、is inevitable.3.1.2 lubricity, na qualitative term describing the abilityof a fluid to affect friction between, and wear to, surfaces inrelative motion under load.3.1.2.1 DiscussionIn this test method, the lubricity of afluid is evaluated by the wear scar, in microns, produced on anoscillating ball
18、from contact with a stationary disk immersed inthe fluid operating under defined and controlled conditions.3.2 Abbreviations:3.2.1 HFRRhigh frequency reciprocating rig3.2.2 WSDwear scar diameter4. Summary of Test Method4.1 A 2-mL test specimen of fuel is placed in the testreservoir of an HFRR.4.2 A
19、vibrator arm holding a nonrotating steel ball andloaded with a 200 g mass is lowered until it contacts a test diskcompletely submerged in the fuel. When the fuel temperaturehas stabilized, the ball is caused to rub against the disk with a1 mm stroke at a frequency of 50 Hz for 75 min.4.3 The test fu
20、el temperature is maintained at 60 C and theambient relative humidity is maintained between 30 % and85 %.4.4 At the conclusion of the test, the upper specimen holderis removed from the vibrator arm and cleaned. The dimensionsof the major and minor axes of the wear scar are measuredunder 100 magnific
21、ation and recorded.5. Significance and Use5.1 Diesel fuel injection equipment has some reliance onlubricating properties of the diesel fuel. Shortened life ofengine components, such as diesel fuel injection pumps andinjectors, has sometimes been ascribed to lack of lubricity in adiesel fuel.5.2 The
22、trend of HFRR test results to diesel injection systempump component distress due to wear has been demonstratedin pump rig tests for some fuel/hardware combinations whereboundary lubrication is believed to be a factor in the operationof the component.55.3 The wear scar generated in the HFRR test is s
23、ensitive tocontamination of the fluids and test materials, the temperatureof the test fuel, and the ambient relative humidity. Lubricityevaluations are also sensitive to trace contaminants acquiredduring test fuel sampling and storage.5.4 The HFRR and Scuffing Load Ball on Cylinder Lubric-ity Evalua
24、tor (SLBOCLE, Test Method D6078) are two meth-ods for evaluating diesel fuel lubricity. No absolute correlationhas been developed between the two test methods.5.5 The HFRR may be used to evaluate the relative effec-tiveness of diesel fuels for preventing wear under the pre-scribed test conditions. C
25、orrelation of HFRR test results withfield performance of diesel fuel injection systems has not yetbeen determined.5.6 This test method is designed to evaluate boundarylubrication properties. While viscosity effects on lubricity inthis test method are not totally eliminated, they are minimized.6. App
26、aratus6.1 High-Frequency Reciprocating Rig (HFRR),6,7(seeFig. 1) capable of rubbing a steel ball loaded with a 200 g massagainst a stationary steel disk completely submerged in a testfuel. The apparatus uses a 1 mm stroke length at a frequency of50 Hz for 75 min. Complete operating conditions are li
27、sted inTable 1.6.2 Test Reservoir, capable of holding a test disk in a rigidmanner beneath the test fuel. The temperature of this reservoir,and consequently the test fuel contained in it, is maintained bymeans of a closely attached electrically controlled heater pad.6.3 Control Unit6,7for controllin
28、g stroke length, frequency,test reservoir temperature, friction force, electrical contactpotential, and test duration, with an electronic data acquisitionand control system.6.4 Microscope, capable of 100 magnification in gradua-tions of 0.1 mm and incremented in divisions of 0.01 mm.6.4.1 Glass Slid
29、e Micrometer7,8with a scale ruled in0.01 mm divisions.6.5 Cleaning Bath, ultrasonic seamless stainless steel tankwith adequate capacity and a cleaning power of 40 W orgreater.6.6 Desiccator, capable of storing test disks, balls, andhardware.5Nikanjam, M., Crosby, T., Henderson, P., Gray, C., Meyer,
30、K, and Davenport,N., “ISO Diesel Fuel Lubricity Round Robin Program,” SAE, Paper No. 952372,SAE Fuels and Lubricants Meeting, Oct. 16-19, 1995, Toronto, Canada.6The sole source of supply of the apparatus known to the committee at this timeis PCS Instruments, 78 Stanley Gardens, London W3 7SZ, Englan
31、d.7If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.8The sole source of supply of the apparatus known to the commit
32、tee at this timeis Catalog No. 31-16-99 from Bausch diesel fuel; friction; HFRR; lu-bricity; wear11Nikanjam, M., Rutherford, J., “Improving the Precision of the HFRR LubricityTest,” SAE Paper No. 2006-01-3363.12Supporting data have been filed at ASTM International Headquarters and maybe obtained by
33、requesting Research Report RR:D02-1718.D7688 184ANNEX(Mandatory Information)A1. MEASUREMENT OF HFRR WEAR SCARSINTRODUCTIONAnnex A of ISO 12156-1:2006 (E) Measurement of HFRR wear scars, used by permission fromISO/CS.A1.1 The appearance of the wear scar on the ball can varywith fuel type, particularl
34、y when lubricity additives are present.In general, the wear scar appears to be a series of scratches inthe direction of motion of the ball, somewhat larger in the xdirection than in the y direction.A1.2 In some cases, for example when low-lubricity refer-ence fluids are tested, the boundary between
35、the scar and thediscolored (but unworn) area of the ball is distinct, and it iseasy to measure the scar size. In other cases, the centralscratched part of the scar is surrounded by a less distinct wornarea, and there is no sharp boundary between the worn andunworn areas of the ball. In these cases,
36、it can be more difficultto see or measure the true scar shape; as shown in Fig. A1.1,the overall wear scar comprises the distinct and the less distinctareas.A1.3 Photographic examples of various wear scar shapesare shown in Fig. A1.2, together with an assessment of theoverall scar boundary.D7688 185
37、FIG. A1.1 Example of a Wear Scar with an Indistinct BoundaryD7688 186FIG. A1.2 Examples of Wear ScarsD7688 187SUMMARY OF CHANGESSubcommittee D02.E0 has identified the location of selected changes to this standard since the last issue(D7688 11 (2016) that may impact the use of this standard. (Approve
38、d Aug. 1, 2018.)(1) Revised subsections 7.8 and 7.9, adding new subsections7.8.1 and 7.9.1.(2) Added new Note 2.FIG. A1.2 Examples of Wear Scars (continued)D7688 188ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this
39、 standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be
40、reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of therespo
41、nsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, Wes
42、t Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 189
