ASTM_D_5621_-_07_2013.pdf

Designation:D562107(Reapproved 2013)Standard Test Method forSonic Shear Stability of Hydraulic Fluids1This standard is issued under the fixed designation D5621;the number immediately following the designation indicates the year oforiginal 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 shearstability of hydraulic fluids in terms of the final viscosity 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 test method uses millimetres squared per second(mm2/s),an SI unit,as the unit of viscosity.For information,the equivalent unit,cSt,is shown in parentheses.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 and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids(and Calculation of Dynamic Viscos-ity)D2603 Test Method for Sonic Shear Stability of Polymer-Containing OilsD6022 Practice for Calculation of Permanent Shear StabilityIndex3.Summary of Test Method3.1 Aconvenient volume of hydraulic fluid is irradiated in asonic oscillator for a period of time and the viscosities beforeand after irradiation are determined by Test Method D445.Astandard reference fluid containing a readily sheared polymer isrun frequently to ensure that the equipment imparts a con-trolled amount of sonic energy 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 was developed using Test MethodD260391.4.2 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 polymers.Correlation with performance in the case ofhydraulic applications has been established.5.Apparatus5.1 Sonic Shear Unit,fixed frequency oscillator and sonichorn.5.2 AuxiliaryEquipmentTofacilitateuniformperformance,the following auxiliary equipment is recom-mended:5.2.1 Cooling Bath or Ice 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 D445.6.Reference Fluids6.1 The reference fluid is ASTM Reference Fluid B,4apetroleum 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,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.07 on Flow Properties.Current edition approved Oct.1,2013.Published October 2013.Originallyapproved in 1994.Last previous edition approved in 2007 as D5621 07.DOI:10.1520/D5621-07R13.2Stambaugh,R.L.,Kopko,R.J.,and Roland,T.F.,“Hydraulic PumpPerformanceA Basis for Fluid Viscosity Classification”,SAE Paper No.901633.Available from Society of Automotive Engineers,400 Commonwealth Dr.,Warrendale,PA 15096.3For 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.4The sole source of supply of the fluid known to the committee at this time isEvonik OilAdditives USA,723 Electronic Drive,Horsham,PA190442228.If youare aware of alternative suppliers,please provide this information to ASTMInternational Headquarters.Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 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 comparison 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