1、Designation: D7688 11 (Reapproved 2016)Standard 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 ofori
2、ginal 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. Scope1.1 This test method covers the evaluation of the lubricity ofdies
3、el fuels using a 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
4、can be used in diesel 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
5、-way to establish 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 thes
6、afety 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 applicableregulatory limitations prior to use. Specific warning statementsare given in Section 7.2. Referenced Documents2.1 AS
7、TM 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 Trace ContaminationD6078 Test Meth
8、od 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:3SAE-AMS 6440 Steel, Bars, Forgi
9、ngs, 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 surfaces in relative motion aredeterm
10、ined 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 orchemically reacted soft films (usually very thin) supportcontact loads. As a r
11、esult, some wear 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 an
12、oscillating ball from contact with a stationary disk immersed inthe fluid operating under defined and controlled conditions.3.2 Abbreviations:3.2.1 HFRRhigh frequency reciprocating rig1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants
13、 and is the direct responsibility ofSubcommittee D02.E0 on Burner, Diesel, Non-Aviation Gas Turbine, and MarineFuels.Current edition approved April 1, 2016. Published May 2016. Originallypublished in 2011. Last previous edition approved in 2011 as D7688 11. DOI:10.1520/D7688-11R16.This test method w
14、as 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 information, refer to the standards Document Summary page onthe ASTM website.3A
15、vailable 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.ansi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, We
16、st Conshohocken, PA 19428-2959. United States13.2.2 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 vibrator arm holding a nonrotating steel ball andloaded with a 200 g mass is lowered until it contacts a test diskcomplet
17、ely 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 fuel temperature is maintained at 60 C and theambient relative humidity is maintained between 30 % and85 %.4.4 At the concl
18、usion 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 magnification and recorded.5. Significance and Use5.1 Diesel fuel injection equipment has some reliance onlubricating properties
19、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 trend of HFRR test results to diesel injection systempump component distress due to wear has been demonstratedin pump rig
20、 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 sensitive tocontamination of the fluids and test materials, the temperatureof the test fuel, and the ambient relative humi
21、dity. 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 Evaluator (SLBOCLE, Test Method D6078) are two meth-ods for evaluating diesel fuel lubricity. No absolute correlationhas been d
22、eveloped 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. Correlation of HFRR test results withfield performance of diesel fuel injection systems has not yetbeen determined.5.6 Thi
23、s test method is designed to evaluate boundarylubrication properties. While viscosity effects on lubricity inthis test method are not totally eliminated, they are minimized.6. Apparatus6.1 High-Frequency Reciprocating Rig (HFRR),6,7(seeFig. 1) capable of rubbing a steel ball loaded with a 200 g mass
24、against 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 listed inTable 1.6.2 Test Reservoir, capable of holding a test disk in a rigidmanner beneath the test fuel. The temperature
25、 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 controlling stroke length, frequency,test reservoir temperature, friction force, electrical contactpotential, and test duration, wi
26、th 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 Slide Micrometer7,8with a scale ruled in0.01 mm divisions.6.5 Cleaning Bath, ultrasonic seamless stainless steel tankwith ade
27、quate capacity and a cleaning power of 40 W orgreater.6.6 Desiccator, capable of storing test disks, balls, andhardware.7. Reagents and Materials7.1 Acetone, reagent grade (WarningExtremely flam-mable. Vapors may cause flash fire).7.2 Compressed Air, containing less than 0.1 ppmv hydro-carbons and 5
28、0 ppmv water. (WarningCompressed gasunder high pressure. Use with extreme caution in the presenceof combustible material.)7.3 Gloves, appropriate for the reagents used.7.4 Reference Fluids:5Nikanjam, M., Crosby, T., Henderson, P., Gray, C., Meyer, K, and Davenport,N., “ISO Diesel Fuel Lubricity Roun
29、d 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, England.7If you are aware of alternative suppliers, please
30、 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 committee at this timeis Catalog No. 31-16-99 from Bausch
31、diesel fuel; friction; HFRR; lu-bricity; wear10Nikanjam, M., Rutherford, J., “Improving the Precision of the HFRR LubricityTest,” SAE Paper No. 2006-01-3363.11Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1718.D7688 11 (201
32、6)4ANNEX(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, particularly when lubricity additives are present.In gen
33、eral, 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 the scar and thediscolored (but unworn) area
34、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, it can be more difficultto see or measure the
35、 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 11 (2016)5FIG. A1.1 Example of a Wear Scar with
36、an Indistinct BoundaryD7688 11 (2016)6FIG. A1.2 Examples of Wear ScarsD7688 11 (2016)7ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of t
37、he 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 reviewed every five years andif not revised, either reapproved or withdrawn. Yo
38、ur 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 theresponsible technical committee, which you may attend. If you feel that your comment
39、s 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, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or mul
40、tiple 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:/ A1.2 Examples of Wear Scars (continued)D7688 11 (2016)8
