1、Designation: D 5621 01An American National StandardStandard Test Method forSonic Shear Stability of Hydraulic Fluids1This standard is issued under the fixed designation D 5621; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the evaluation of the shearstability of hydraulic fluids in terms of the final viscosit
3、y thatresults from irradiating a sample of the hydraulic fluid in asonic oscillator.1.2 Evidence has been presented that a good correlationexists between the shear degradation that results from sonicoscillation and that obtained in a vane pump test procedure.21.3 This standard does not purport to ad
4、dress 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.1.4 This test method uses millimetres squared per secon
5、d(mm2/s), an SI unit, as the unit of viscosity. For information,the equivalent unit, cSt, is shown in parentheses.2. Referenced Documents2.1 ASTM Standards:D 445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (the Calculation of Dynamic Viscos-ity)3D 2603 Test Method for Sonic
6、Shear Stability of Polymer-Containing Oils43. Summary of Test Method3.1 A convenient volume of hydraulic fluid is irradiated in asonic oscillator for a period of time and the change in viscosityis determined by Test Method D 445.Astandard reference fluidcontaining a readily sheared polymer is run fr
7、equently toensure that the equipment imparts a controlled amount of sonicenergy to the sample.3.2 The conditions to obtain the data for the precisionstatement were: 30 mL sample, 12.5 min calibration, and 40min sample irradiation at 0C jacket temperature.4. Significance and Use4.1 This test method w
8、as developed using Test MethodD 2603 91.4.2 This test method permits the evaluation of shear stabilitywith minimum interference from thermal and oxidative factorsthat may be present in some applications. It has been foundapplicable to fluids containing both readily sheared and shear-resistant polyme
9、rs. Correlation with performance in the case ofhydraulic applications has been established.5. Apparatus5.1 Sonic Shear Unit, fixed frequency oscillator and sonichorn.55.2 Auxiliary EquipmentTo facilitate uniform perfor-mance, the following auxiliary equipment is recommended:5.2.1 Cooling Bath or Ice
10、 Bath, to maintain a jackettemperature of 0C.5.2.2 Griffn 50mL Beaker, borosilicate glass.5.2.3 Sonic-Insulated Box, to enclose the sonic horn toreduce the ambient noise level produced by the sonic shearunit.5.3 Viscometer, any viscometer and bath meeting the re-quirements of Test Method D 445.6. Re
11、ference Fluids6.1 The reference fluid is ASTM Reference Fluid B,6apetroleum oil containing a polymer capable of being brokendown by turbulence at high rates of shear. This oil has a1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct
12、 responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved Aug. 10, 2001. Published September 2001. Originallypublished as D 5621-94. Last previous edition D 5621-94.2Stambaugh, R. L., Kopko, R. J., and Roland, T. F., “Hydraulic PumpPerformanceA Basis for Fluid Viscosity Class
13、ification”, SAE Paper No. 901633.Available from Society of Automotive Engineers, 400 Commonwealth Dr., Warren-dale, PA 15096.3Annual Book of ASTM Standards, Vol 05.01.4Annual Book of ASTM Standards, Vol 05.02.5In the round robin program, equipment from Sonic Systems, Inc., 109 PheasantRun, Newtown,
14、PA 18040 and Heat Systems Ultrasonic, Inc., 1938 New Highway,Farmingdale, NY 11735, were found to be satisfactory.6This fluid can be obtained from RohMax USA, 723 Electronic Drive, Horsham,PA 190442228.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-295
15、9, United States.viscosity of about 13.6 mm2/s (cSt) at 40C. The viscosity of aspecific lot is supplied by the provider of that lot.7. Calibration of Apparatus7.1 The reference fluid provides a practical way to definethe performance (severity level) of a sonic oscillator unit sothat satisfactory com
16、parison can be made between tests run ondifferent days in the same unit and between tests run withdifferent units.7.2 The decrease in viscosity observed for a given hydraulicfluid on irradiation in an oscillator unit depends on a number offactors; these include sample volume, irradiation time, andos
17、cillator power setting. Frequency of the generator is 23 6 2kHz. Typical power settings are in the range of 50 watts.Manual tuning of the oscillator-horn combination is alsorequired in some instruments in order to ensure efficiency ofenergy coupling between the two units. The procedure de-scribed in
18、 7.3 is recommended for establishing a reproducibleperformance level for a given unit.7.3 Confirm and record the 40C viscosity of the referencefluid. Introduce 30 mL (room temperature) of the referencefluid into the 50mL Griffin beaker. Immerse the beaker in icewater or a constant temperature bath a
19、t 0C until the samplefluid level is below the liquid level in the bath. The beakershould be maintained in a vertical position in the bath. Securebeaker in this position and condition the sample for 12.5 minbefore commencing irradiation. Immerse the sonic horn intothe sample fluid until the tip is at
20、 least 10 mm below the surfaceof fluid (see Fig. 1) in order to ensure that the tip remainssubmerged during the test. Exercise care to avoid contact of thetip with the bottom of the beaker as this will shorten tip life.The horn should be placed in a vertical position in the fluid andcentered in the
21、beaker (a weighted ring stand may be used tosupport the horn in this position). True vertical positioning isnot critical and is intended primarily to minimize liquidsplashing during irradiation. Irradiate the fluid for 12.5 min ata preselected power setting. Determine the decrease in refer-ence flui
22、d viscosity measured at 40C. Repeat as necessary todetermine the proper power setting to produce a viscositychange at 40C of 15.0 % (61 %). Use this power setting forsubsequent test runs. Daily recalibration of the apparatus isrequired because the power setting required to produce a statedviscosity
23、loss will probably vary from day to day. Experiencewith a given apparatus set will determine whether morefrequent calibration is required. Calibration in this manner willensure that repeatable severity levels are established.8. Procedure8.1 Clean the sonic horn using a lintless wiper and optionalsol
24、vent and calibrate the apparatus as described in 7.3. Intro-duce 30 mL of the hydraulic fluid sample to be tested into aclean 50mL Griffin beaker and immerse in the constanttemperature bath at 0C. The beaker should be in a verticalposition. Allow the sample to equilibrate for 12.5 min. Im-merse the
25、sonic horn in the fluid as described in 7.3. Irradiatethe sample for 40 min at exactly the same power settingdetermined in 7.3. Upon completion of irradiation, remove thesample and clean the sonic horn in preparation for the next run.8.2 Determine the viscosity of the sample by Test MethodD 445 befo
26、re and after irradiation.9. Report9.1 Report the initial and irradiated 40C viscosity of thehydraulic fluid.10. Precision and Bias710.1 RepeatabilityThe difference between two indepen-dent results obtained by the same operator with the sameapparatus under constant operating conditions on identical t
27、estmaterial would, in the long run, in the normal and correctoperation of the test method, differ from the mean by greaterthan 0.38 mm2/s (cSt) in only one case in twenty.10.2 ReproducibilityThe difference between two indepen-dent results obtained by different operators working in differentlaborator
28、ies on identical test material would, in the long run, in7Supporting data are available from ASTM Headquarters. Request RR: D02-1337.FIG. 1 Schematic of Sonic Probe Type Apparatus, SupportSystems, Cabinet, and Power SupplyD5621012the normal and correct operation of the test method, differ fromthe me
29、an by greater than 0.60 mm2/s (cSt) in only one case intwenty.10.3 BiasThe bias of this test method has not beendetermined because there is insufficient data on the relevantreference (test) standard.11. Keywords11.1 hydraulic fluid; shear stability; sonic shear test; viscos-ity stableASTM Internatio
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33、, 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 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).D5621013
