1、Designation: D2714 94 (Reapproved 2009)Standard Test Method forCalibration and Operation of the Falex Block-on-RingFriction and Wear Testing Machine1This standard is issued under the fixed designation D2714; 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1
3、This test method covers the calibration and operation ofa block-on-ring friction and wear testing machine.1.2 The values in SI units are to be regarded as standard.The values given in parentheses are mathematical conversionsto SI units that are provided for information only.1.3 This standard does no
4、t 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. Terminology2.1 Definitions:2.1.1 coef
5、fcient of friction, or fin tribology, the dimen-sionless ratio of the friction force (F) between two bodies to thenormal force (N) pressing these two bodies together.orf 5 F/N! (1)2.1.1.1 DiscussionA distinction is often made betweenstatic coeffcient of friction and kinetic coeffcient of friction.2.
6、1.2 friction forcethe resisting force tangential to theinterface between two bodies when, under the action of anexternal force, one body moves or tends to move relative to theother.2.1.3 kinetic coeffcient of frictionthe coefficient of fric-tion under conditions of macroscopic relative motion betwee
7、ntwo bodies.2.1.4 weardamage to a solid surface, generally involvingprogressive loss of material, due to relative motion betweenthat surface and a contacting substance or substances.3. Summary of Test Method3.1 The test machine is operated using a steel test ringrotating against a steel test block,
8、the specimen assembly beingpartially immersed in the lubricant sample. The velocity of thetest ring is 7.9 6 0.16 m/min (26 6 0.52 ft/min) which isequivalent to a spindle speed of 72 6 1 rpm. The specimens aresubjected to 68 kg (150 lb) normal load applied by 6.8 kg(15 lb) of dead weight on the 10:1
9、 ratio lever system. Testduration is 5000 cycles.3.2 Three determinations are made: (1) The friction forceafter a certain number of revolutions, (2) the average width ofthe wear scar on the stationary block at the end of the test, and(3) the weight loss for the stationary block at the end of the tes
10、t.4. Significance and Use4.1 This test method is used for the calibration of ablock-on-ring testing machine by measuring the friction andwear properties of a calibration fluid under the prescribed testconditions.4.2 The user of this test method should determine to his orher own satisfaction whether
11、results of this test procedurecorrelate with field performance or other bench test machines.If the test conditions are changed, wear values can change andrelative ratings of fluids can be different.5. Apparatus5.1 Falex Block-on-Ring Test Machine,2shown in Fig. 1and Fig. 2 and described in detail in
12、 Annex A1.NOTE 1Consult the instruction manual for each machine to determinerespective capabilities and limitations.5.2 Analytical Balance, capable of weighing to the nearest0.1 mg.5.3 Measuring Magnifier Glass, with SI or inch-poundcalibration so that the scar width can be measured with aprecision
13、of 0.01 mm, or equivalent.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.L0.05 on Solid Lubricants.This test method was prepared under the joint sponsorship of the AmericanSociety of Lubricatio
14、n Engineers with the cooperation of the Coordinating ResearchCouncil, Inc. (CRC) Aviation Committee on Bonded Solid-Film Lubricants.Accepted by ASLE September 1968.Current edition approved Oct. 1, 2009. Published November 2009. Originallyapproved in 1968. Last previous edition approved in 2003 as D2
15、71494(2003).DOI: 10.1520/D2714-94R09.2Trademarked and manufactured by Falex Corp., 1020 Airpark Dr., SugarGrove, IL 60554.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Reagents and Materials6.1 Test Rings, Falex Type S-10,2SAE 4
16、620 carburizedsteel, having a hardness of 58 to 63 HRC. The test ring has awidth of 8.15 mm (0.321 in.), a diameter of 35 mm (1.3775 in.)and a maximum radial run out of 0.013 mm (0.0005 in.). Thesurface roughness shall be 0.15 to 0.30 m (6 to 12 in.) rms.6.2 Test Blocks, Falex Type H-30,2SAE 013tool
17、 steelhaving two ground test surfaces of 0.10 to 0.20 m (4 to 8 in.)rms. The test block has a test surface width of 6.35 mm (0.250in.) and a length of 15.76 mm (0.620 in.). The test block has ahardness of 27 to 33 HRC.6.3 Solvents, safe, nonfilming, nonchlorinated.NOTE 2Each user should select a sol
18、vent that can meet the applicablesafety standards and still thoroughly clean the parts.6.4 Calibration Fluid, consisting of white mineral oil con-forming to U. S. Pharmacopeia XVII, p. 399, and with aviscosity at 37.8C (100F) of 63 to 65 cSt.7. Preparation of Apparatus7.1 Before each test, thoroughl
19、y clean the specimen holderand chamber as well as the tapered section, threaded section,lock nut, lock washer, a new test ring and block using solventsselected in 6.3.7.2 Weigh each test ring and test block to the nearest 0.1 mgon the analytical balance. Then store the specimens in adesiccator until
20、 ready for use.7.3 Place the block holder on the block and carefully placeblock and holder in upper specimen holder in test chamber.Mount the test ring on the test shaft, taking care not to touchthe test area. Tighten the test ring on the shaft with 440 N (100lbf) as measured on the friction force m
21、eter on the digitalinstrument unit.7.4 Place the heater door in position and fill the chamberwith test fluid to about halfway on the spindle (half of the testring is immersed). This volume must be measured (approxi-mately 100 mL) and the same amount used for each test. Setthe temperature control of
22、the oil reservoir to 43.3C (110F).It is preferable to control the temperature of the liquid beingtested, but if the machine is not equipped with a temperaturecontroller indicator, then record the liquid temperature.8. Calibration8.1 A machine shall be judged to be in acceptable conditionwhen the res
23、ults obtained on the calibration fluid fall within thefollowing limits:8.1.1 Wear measurement is between 1.70 and 2.90 mm.8.1.2 Friction force after 4500 revolutions is between 66and 97 N (15.0 and 22.0 lbf).9. Procedure9.1 With the revolution counter set at zero, gently place a6.78-kg (15-lb) load
24、on the bale rod, being very careful toavoid shock-loading. When the fluid reaches temperature of43.3C (110F) start the machine and bring the speed to 72rpm. Record the friction force and the temperature of the liquidat 200, 400, 600, and 4500 revolutions and check the speed ateach of these times. St
25、op the machine at 5000 revolutions.Remove the test block and test ring and clean them thoroughlyusing solvents selected in 6.3. Remove any excess wearparticles that have accumulated on the side of the scar bybrushing with a camels hair brush; weigh the test ring and testblock to the nearest 0.1 mg a
26、nd measure the width of the wearscar of the test block at three points: in the center and 1 mmaway from each edge as shown in Fig. 3. Four tests are requiredto establish a satisfactory average.10. Calculation and Report10.1 Report the friction force at 200, 400, 600, and 4500revolutions, the weight
27、loss for the test block and test ring, andthe average wear scar width. Fig. 3.3SAE 01 is also known as Starrett 496 or Marshall Oil-crat.FIG. 1 Falex Block-On-Ring Variable Drive Testing MachineFIG. 2 Falex Block-On-Ring Test Machine with MicroprocessorData Acquisition and Control SystemFIG. 3 Test
28、Specimen Wear Scar MeasurementD2714 94 (2009)210.2 Calculate the coefficient of friction values from thefriction force value as follows:f 5 F/W (2)where:f = coefficient of friction,F = measured friction force, kg (lb), andW = normal load, kg (lb).11. Precision and Bias11.1 The following criteria sho
29、uld be used for judging theacceptability of results (95 % confidence):11.1.1 Wear Measurement:11.1.1.1 RepeatabilityThe difference between successivetest results, obtained by the same operator with the sameapparatus under constant operating conditions on identical testmaterial would, in the long run
30、, and in the normal and correctoperation of the test method, exceed the following value onlyin one case in twenty:Repeatability 5 0.73 mm (3)11.1.1.2 ReproducibilityThe difference between two,single and independent results, obtained by different operatorsworking in different laboratories on identica
31、l test materialwould, in the long run, and in the normal and correct operationof the test method, exceed the following values only in onecase in twenty:Reproducibility 5 1.20 mm (4)11.1.2 Friction Force after 4500 Revolutions:11.1.2.1 RepeatabilityThe difference between successivetest results, obtai
32、ned by the same operator with the sameapparatus under constant operating conditions on identical testmaterial would, in the long run, and in the normal and correctoperation of the test method, exceed the following values onlyin one case in twenty:Repeatability 5 29 N 6.6 lbf! (5)11.1.2.2 Reproducibi
33、lityThe difference between two,single and independent results, obtained by different operatorsworking in different laboratories on identical test materialwould, in the long run, and in the normal and correct operationof the test method, exceed the following values only in onecase in twenty:Reproduci
34、bility 5 31 N 7.0 lbf! (6)11.2 BiasSince there is no accepted reference materialsuitable for determining the bias for the procedure in TestMethod D2714 for measuring friction and wear, no statementon bias is being made.12. Keywords12.1 block-on-ring; coefficient of friction; friction; wearANNEX(Mand
35、atory Information)A1. DESCRIPTION OF THE FALEX BLOCK-ON-RING FRICTION AND WEAR TESTING MACHINEA1.1 A stationary rectangular test block is pressed with apredetermined load, maximum 584 kg (1300 lb), against arotating ring (Fig. A1.1). The load is accurately maintainedthroughout the test. Bearing pres
36、sures (average Hertz pres-sures) in the line contact area between the rectangular speci-men and the rotating ring can range up to 758 MN/m2(110 000psi).A1.2 Resulting friction is indicated throughout the test by adigital indicator. A counter records the number of revolutionsof the test specimen. One
37、 criterion in the test is a preselectedmaximum for friction. For this purpose an automatic cutoff onthe friction indicator can be set for any preselected value offriction and the machine will shut off upon reaching it.A1.3 In a substitute method, a thermocouple is embeddedin the specimen and a tempe
38、rature recorder controller termi-nates the test when the temperature of the test block reaches apreviously set value.A1.4 The test shaft of the machine is supported by tworoller bearings, and the mandrel end of the shaft protrudesthrough the front panel of the machine where the test speci-mens are m
39、ounted. The test block, which is held stationaryagainst the revolving ring, is restrained from horizontal move-ment. The design of this block holder allows the test block toalign itself automatically in a manner prescribed by ASTMspecifications for compression-loaded specimens. This main-tains unifo
40、rm loading throughout the area of contact betweenthe specimens regardless of the force existing between them.A1.5 The normal force between the test specimens isproduced by hanging dead weights on the lower end of a leversystem that is designed in such a way as to allow the full valueof the friction
41、force to be transmitted to the frictional load pickup device.A1.6 Speed ranges with variable speed control are availablefrom 0.5 to 7200 rpm. Fluid lubricants can be tested up to amaximum of 204C (400F). With optional equipment, the testchamber can be pressurized to 1.03 MPa (150 psi) run inspecial
42、atmospheres or run in vacuum.A1.7 The friction force indicator is direct reading in poundsor kilograms and is fitted with an infinitely adjustable limitcontrol that allows the operator to preset the value of friction atwhich the machine will stop.A1.8 An electronic six-digit cycle counter is mounted
43、 onthe front of the digital instrumentation unit. It is equipped withan automatic cut-off.D2714 94 (2009)3A1.9 A completely automated version is available incorpo-rating a computer interface to automatically control load,speed, temperature, and duration.ASTM International takes no position respectin
44、g 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 the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standa
45、rd 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. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Internationa
46、l Headquarters. Your comments will receive careful consideration at a meeting of theresponsible 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.Th
47、is standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West 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).FIG. A1.1 Functional Diagram of the Falex Block-On-Ring Testing MachineD2714 94 (2009)4
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