ASTM_F_2161_-_10.pdf

Designation:F216110Standard Guide forInstrument and Precision Bearing LubricantsPart 1 Oils1This standard is issued under the fixed designation F2161;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 guide is a tool to aid in the choice of an oil forprecision rolling element bearing applications.There are twoareas where this guide should have the greatest impact:(1)when a lubricant is being chosen for a new bearing applicationand(2)when a lubricant for a bearing has to be replacedbecause the original lubricant specified for the bearing can nolonger be obtained.The Report(Section 5)contains a series oftests performed by the same laboratory on a wide variety of oilscommonly used in bearing applications to allow comparisonsof those properties of the oil that the committee thought to bemost important when making a choice of lubricant.This guidecontains a listing of the properties of oils by chemical type,thatis,ester,silicone,and so forth.This organization is necessarysince the operational requirements in a particular bearingapplication may limit the choice of lubricant to a particularchemical type due to its temperature stability,viscosity indexor temperature-vapor pressure characteristics,and so forth.TheReport includes the results of tests on the oils included in thisstudy.The Report recommends replacement lubricants forthose oils tested that are no longer available.The Report alsoincludes a glossary of terms used in describing/discussing thelubrication of precision and instrument bearings.The Reportpresents a discussion of elastohydrodynamic lubrication asapplied to rolling element bearings.1.2 Although other compendia of lubricant properties havebeen published,for example,the Barden Product Standard,Lubricants2and the NASA Lubricant Handbook for the SpaceIndustry3,none have centered their attention on lubricantscommonly used in precision rolling element bearings(PREB).The PREB put a host of unique requirements upon a lubricant.The lubricant must operate at both high and low temperatures.The lubricant must provide lubrication for months,if not years,without replenishment.The lubricant must be able to supporthigh loads but cannot be so viscous that it will interfere withthe operation of the bearing at very high speeds or lowtemperatures,or both.The lubricant must provide boundarylubrication during low-speed or intermittent operation of thebearing.And,in many applications,its vapor pressure must below enough under operating conditions that evaporative lossesdo not lead to lubricant depletion or contamination of nearbycomponents.These and other considerations dictated the seriesof tests that were performed on each lubricant included in thisstudy.1.3 Another important consideration was encompassed inthis study.Almost all of the testing was performed by the samelaboratory,The Petroleum Products Research Department ofthe Southwest Research Institute in San Antonio,Texas,usingASTM procedures.This continuity of testing should form asolid basis for comparing the properties of the multitude oflubricants tested by avoiding some of the variability introducedwhen lubricants are tested by different laboratories usingdifferent or even the“same”procedures.1.4 It should be noted that no functional tests(that is,bearing tests)were performed.The results of the four-ball weartest give some comparison,“a figure of merit,”of the lubrica-tion properties of the oils under the condition of this test.Butexperience has shown that testing the lubricant in runningbearings is the best means of determining lubricant perfor-mance.2.Referenced Documents2.1 ASTM Standards:4D92 Test Method for Flash and Fire Points by ClevelandOpen Cup TesterD97 Test Method for Pour Point of Petroleum ProductsD445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids(and Calculation of Dynamic Viscos-ity)D974 Test Method for Acid and Base Number by Color-Indicator Titration1This guide is under the jurisdiction of ASTM Committee F34 on RollingElement Bearings and is the direct responsibility of Subcommittee F34.02 onTribology and was developed by DoD Instrument Bearing Working Group(IBWG)former F34.Current edition approved Jan.1,2010.Published February 2010 originallyapproved in 2001.Last previous edition approved in 2001 as F216101.DOI:10.1520/F2161-10.2Product Standard,Lubricants,available from The Barden Corp.,Danbury,CT.3NASA Lubricant Handbook for the Space Industry,Ernest L.McMurtrey,NASA Technical Memorandum TM-86556,George C.Marshall Space Flight Center,National Aeronautics and Space Administration,December 1985.4For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,ref