1、Designation: F 2489 06Standard Guide forInstrument and Precision Bearing LubricantsPart 2Greases1This standard is issued under the fixed designation F 2489; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 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 guide is a tool to aid in the choice of lubricatinggrease for precision rolling element bearing applications. Therecommendatio
3、ns in this guide are not intended for generalpurpose bearing applications There are two areas where thisguide should have the greatest impact: (1) when lubricatinggrease is being chosen for a new bearing application and (2)when grease for a bearing has to be replaced because theoriginal grease speci
4、fied for the bearing can no longer beobtained. The Report (see Section 5) contains a series of testson a wide variety of greases commonly used in bearingapplications to allow comparisons of those properties of thegrease that the committee thought to be most important whenmaking a choice of lubricati
5、ng grease. Each test was performedby the same laboratory. This guide contains a listing of theproperties of greases by base oil type, that is, ester, perfluo-ropolyether (PFPE), polyalphaolefin (PAO), and so forth. Thisorganization is necessary since the operational requirements ina particular beari
6、ng application may limit the choice of greaseto a particular base oil type and thickener due to its temperaturestability, viscosity index or temperature-vapor pressure char-acteristics, etc. The guide provides data to assist the user inselecting replacement greases for those greases tested that aren
7、o longer available. The guide also includes a glossary of termsused in describing/discussing the lubrication of precision andinstrument bearings.1.2 The lubricating greases presented in this guide arecommonly used in precision rolling element bearings (PREB).These greases were selected for the testi
8、ng based on the greasesurvey obtained from DoD, OEM and grease manufactures andevaluated according to the test protocol that was designed bySubcommittee F34 on Tribology. This test protocol covers theessential requirements identified for precision bearing greases.The performance requirements of thes
9、e greases are veryunique. They are dictated by the performance expectations ofprecision bearings including high speed, low noise, extendedlife, and no contamination of surrounding components by thebearings lubricant system. To increase the reliability of testdata, all tests were performed by a DoD l
10、aboratory and threeindependent testing laboratories. There were no grease manu-facturers data imported except for base oil viscosity. Most oftests were performed by U.S. Army TankAutomotive Re-search, Development and Engineering Center (TARDEC) andthree independent laboratories, and the results were
11、 monitoredby the Naval Research Laboratory (NRL). This continuity oftesting should form a solid basis for comparing the propertiesof the multitude of lubricating greases tested by avoiding someof the variability introduced when greases are tested bydifferent laboratories using different or even the
12、“same” pro-cedures. Additional test data will be considered for inclusion,provided the defined protocol is followed and the tests areperformed by independent laboratories.1.3 This study was a part of DoD Aging Aircraft Replace-ment Program and supported by Defense Logistic Agent(DLA) and Defense Sup
13、ply Center Richmond (DSCR).21.4 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
14、prior to use.2. Referenced Documents2.1 ASTM Standards:3D 217 Test Methods for Cone Penetration of LubricatingGreaseD 972 Test Method for Evaporation Loss of LubricatingGreases and OilsD 1264 Test Method for Determining the Water WashoutCharacteristics of Lubricating GreasesD 1742 Test Method for Oi
15、l Separation from LubricatingGrease During StorageD 1743 Test Method for Determining Corrosion Preventive1This guide is under the jurisdiction of ASTM Committee F34 on RollingElement Bearings and is the direct responsibility of Subcommittee F34.02 onTribology.Current edition approved May 1, 2006. Pu
16、blished May 2006.2Rhee, In-Sik, “Precision Bearing Grease Selection Guide,” U.S. Army TARDECTechnical Report No. 15688, Defense Technical Information Center, 8725 John. J.Kingman Rd., Suite 0944, Ft. Belvoir, VA 220606218.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontac
17、t ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Properties of Lubricatin
18、g GreasesD 1831 Test Method for Roll Stability of LubricatingGreaseD 2265 Test Method for Dropping Point of LubricatingGrease Over Wide Temperature RangeD 2266 Test Method for Wear Preventive Characteristics ofLubricating Grease (Four-Ball Method)D 2596 Test Method for Measurement of Extreme-Pressur
19、eProperties of Lubricating Grease (Four-Ball Method)D 3527 Test Method for Life Performance of AutomotiveWheel Bearing GreaseD 4048 Test Method for Detection of Copper Corrosionfrom Lubricating GreaseD 4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD 4289 Test Method for El
20、astomer Compatibility of Lubri-cating Greases and FluidsD 4425 Test Method for Oil Separation from LubricatingGrease by Centrifuging (Koppers Method)D 4693 Test Method for Low-Temperature Torque ofGrease-Lubricated Wheel BearingsD 5483 Test Method for Oxidation Induction Time of Lu-bricating Greases
21、 by Pressure Differential Scanning Calo-rimetryE 1131 Test Method for Compositional Analysis by Ther-mogravimetryF 2161 Guide for Instrument and Precision BearingLubricantsPart 1 OilsF 2488 Terminology for Rolling Element Bearings2.2 Government Documents:4Federal Standard Test Method 791C, 3005.4 Di
22、rt Content ofGreaseMIL-G-25537 Aircraft Helicopter Bearing GreaseMIL-PRF-23827 Aircraft and instrument GreaseMIL-PRF-81322 Aircraft Wide Temperature Range GreaseMIL-PRF-83261 Aircraft Extreme PressureMIL-PRF-10924 Grease, Automotive and ArtilleryMIL-G-27617 Grease, Aircraft and Instrument, Fuel andO
23、xidizer ResistantMIL-G-21164 Molybdenum Disulfide GreaseMIL-G-25760 Grease, Aircraft, Ball and Roller Bearing,Wide Temperature RangeMIL-L-15719 High Temperature Electrical Bearing GreaseDoD-G-24508 Multipurpose Grease2.3 Industrial Standards:SKF Be-Quite Noise Test Method5TA Rheometry Procedure for
24、Steady Shear Flow Curve6Wet Shell Roll Test Method72.4 SAE Standard:8SAE-AMS-G-81937 Grease, Instrument, Ultra-Clean, Met-ric3. Terminology3.1 Definitions of Terms Specific to This Standard: Fordefinition of standard terms used in this guide, see TerminologyD 4175 and F 2488 or Compilation of ASTM S
25、tandard Defi-nitions.3.1.1 esters, nesters are formed from the reaction of acidsand alcohols. Esters form a class of synthetic lubricants. Estersof higher alcohols with divalent fatty acids form diesterlubricants while esters of polyhydric alcohols are called thepolyol ester lubricants. These latter
26、 esters have higher viscosityand are more heat-resistant than diesters.3.1.2 mineral oil, noils based on petroleum stocks. Theseoils come in two types, naphthenic and paraffinic. The naph-thenic oils contain unsaturated hydrocarbons, usually in theform of aromatic species. The paraffinic oils are pr
27、imarilysaturated hydrocarbons with only low levels of unsaturation.3.1.3 perfluoropolyethers (PFPE or PFAE), nfully flu-orinated long-chain aliphatic ethers. The perfluoropolyethersshow some extraordinary properties like chemical inertness,nonflammability, high thermal and oxidative resistance, very
28、good viscosity-temperature characteristics, and compatibilitywith a wide range of materials, including metals and plastics.The perfluoropolyethers, however, are not always suitable formetal alloys at elevated temperatures (contact temperatureshigher than about 550F). The perfluoropolyethers are notm
29、iscible with other types of synthetic fluids and mineral oilsand cannot dissolve common lubricant additives.3.1.4 silicone oils, nsynthetic fluids composed of organicesters of long chain complex silicic acids. Silicone oils havebetter physical properties than mineral oils. However, siliconeoils have
30、 poorer lubrication properties, lower load-carryingcapacity, and a strong tendency to spread on surfaces (seesurface tension).3.1.5 synthetic fluids, nlubricating fluids produced bychemical synthesis. The synthetic route to formulate theselubricants allows the manufacturer to introduce those chemica
31、lstructures into the lubricant molecule that will impart specificproperties into the resultant fluid such as very low pour point,good viscosity-temperature relationship, low evaporation loss,long lubricating lifetime, and so forth.3.1.6 lubricating grease, na semi-fluid to solid product ofa dispersi
32、on of a thickener in a liquid lubricant.4. Significance and Use4.1 The purpose of this guide is to report on the testing of,to discuss and compare the properties of, and to provideguidelines for the choice of lubricating greases for precisionrolling element bearings (PREB). The PREB are, for thepurp
33、oses of this guide, meant to include bearings of AnnularBearing Engineers Committee (ABEC) 5 quality and above.This guide limits its scope to lubricating greases used in PREB.4.2 The number of lubricating greases used in PREB in-creased dramatically from the early 1940s to the mid 1990s. Inthe begin
34、ning of this period, petroleum products were the onlywidely available base stocks. Later, synthetic base oils became4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-50985Available from SKF North American Technical Center, 46815
35、 Port St.,Plymouth, MI 48170.6Available from TA Instruments Company, 109 Lukens Drive, New Castle, DE19720-2765.7Available from Southwest Petro-Chem Division, Witco Corp., P.O. Box 1974,Olathe, KS 66061.8Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-
36、0001.F2489062available. They included synthetic hydrocarbons, esters, sili-cones, multiply alkylated cyclopentanes (MAC) and fluori-nated materials, including perfluorinated ethers and the fluo-rosilicones. This broad spectrum of lubricant choices has led tothe use of a large number of different lub
37、ricants in PREBapplications. The U.S. Department of Defense, as a user ofmany PREB, has seen a significant increase in the logisticseffort required to support the procurement and distribution ofthese items. In addition, as time has passed, some of thegreases used in certain PREB are no longer availa
38、ble or requireimproved performances due to advanced bearing technology/requirements. This implies that replacement lubricating greasesmust be found, especially in this era of extending the lifetimeof DoD assets, with the consequent and unprojected demandfor sources of replacement parts.4.3 One of th
39、e primary goals of this study was to take abroad spectrum of the lubricating greases used in PREB and doa comprehensive series of tests on them in order that theirproperties could be compared and, if necessary, potentialreplacement greases be identified. This study is also meant tobe a design guide
40、for choosing lubricating greases for futurePREB applications. This guide represents a collective effort ofmany members of this community who span the spectrum frombearing manufacturers, original equipment manufactures(OEMs), grease manufacturers and suppliers, procurementspecialists, and quality ass
41、urance representatives (QARs) fromDoD and end users both inside and outside DoD.4.4 It is strongly recommend that, prior to replacing a greasein a PREB, all of the existing grease should be removed fromthe bearing. Reactions may occur between incompatiblegreases resulting in severely degraded perfor
42、mance. Whenusers have more than one type of grease in service, mainte-nance practices must be in place to avoid accidental mixing ofgreases. In addition, all fluids used specifically to prolongstorage life of PREBs (preservatives) should be removed priorto lubricating the bearings. Reactions may occ
43、ur which woulddegrade the grease.4.5 The base oils, thickeners, and additives dictates greaseperformances. The properties of many base oils can be found inthe previous study (Guide F 2161). This study included adiscussion of elastohydrodynamic lubrication theory.5. Report5.1 The test results are sum
44、marized in Tables 13. Table 1presents the classification of base oils, thickener types, andmilitary specification products evaluated in this program. Table2 lists the test protocol for this study and covers the testmethods, their test conditions, and the testing laboratories.Table 3 (A-C) provides t
45、he test results of the 38 precisionbearing greases tested. Each grease tested was assigned a codeto mask their source to mitigate any potential bias in the testingresults. The tradename of each grease is listed in ResearchReport F341000.9For the evaluation, each grease was testedfor dropping point,
46、consistency, water and work stability,oxidation stability, oil separation, evaporation loss, wear, EPproperties, corrosion prevention, low temperature characteris-tics, cleanliness, apparent viscosity, grease noise, and greaselife. Compatibility testing with elastomers incorporated intoPREB and thei
47、r environments were not done due to the largenumber of combinations that would require testing to span thepotential mixes of greases and elastomer components thatmight occur in bearing applications. It is recommended that theuser verify grease/elastomer compatibility when needed.5.2 In these tables,
48、 some of the data may not agree withthose of manufacturers due to the variation of the test methodsand their test apparatuses (that is, noise test). All tests wereperformed by a government laboratory and three independentlaboratories. No grease manufacturers performed any of thesetests except for th
49、e base oil viscosities of greases. To increasethe availability of precision bearing greases, these tables willbe revised periodically to include new greases as long as themanufacturer submits test results on their product followingprecisely the protocol defined in the document.6. Application Considerations6.1 This guide applies only to precision bearing greases.The other types of greases such as industrial greases orautomotive general purpose greases are not covered by thisguide.6.1.1 Precision bearing greases contain base oil to which athickener has been added to preven
