1、 SURFACE VEHICLE RECOMMENDED PRACTICE Heavy Duty Vehicle Lubricating Greases SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitabil
2、ity for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyrigh
3、t 2005 SAE International All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER
4、: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA) Fax: 724-776-0790 Email: custsvcsae.org SAE WEB ADDRESS: http:/www.sae.org Issued 2005-08 J2695 ISSUED AUG20051. Scope This SAE Recommended Practice was developed by SAE, and the section “Standard Classification and Specific
5、ation for Service Greases” cooperatively with ASTM, and NLGI. It is intended to assist those concerned with the design of heavy duty vehicle components, and with the selection and marketing of greases for the lubrication of certain of those components on heavy duty vehicles like trucks and buses. Th
6、e information contained herein will be helpful in understanding the terms related to properties, designations, and service applications of heavy duty vehicle greases. 1.1 Rationale Not applicable. 2. References 2.1 Applicable Publications The following publications form a part of this specification
7、to the extent specified herein. Unless otherwise specified, the latest issue of SAE publications shall apply. 2.1.1 SAE PUBLICATIONS Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001, USA. SAE AMS 3217AStandard Elastomer StockTest Slabs SAE AMS 3217/2ATest Slabs, Acrylonitrile Bu
8、tadiene (NBR-L)Low Acrylonitrile, 65-75 SAE AMS 3217/3BTest Slabs, Chloroprene (CR)67-75 SAE J310Automotive Greases SAE J2695 Issued AUG2005 - 2 - 2.1.2 ASTM PUBLICATIONS Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, USA. ASTM D 128Analysis of Lubricating Grease ASTM
9、D 217Cone Penetration of Lubricating Grease ASTM D 566Dropping Point of Lubricating Grease ASTM D 942Oxidation Stability of Lubricating Greases by the Oxygen Bomb Method ASTM D 972Evaporation Loss of Lubricating Greases and Oils ASTM D 1092Apparent Viscosity of Lubricating Greases ASTM D 1263Leakage
10、 Tendencies of Automotive Wheel Bearing Greases ASTM D 1264Water Washout Characteristics of Lubricating Greases ASTM D 1403Cone Penetration of Lubricating Grease Using One-Quarter and One-Half Scale Cone Equipment ASTM D 1404Test Method for Estimation of Deleterious Particles in Lubricating Grease A
11、STM D 1478Low-Temperature Torque of Ball Bearing Greases ASTM D 1742Oil Separation from Lubricating Grease During Storage ASTM D 1743Corrosion Preventive Properties of Lubricating Greases ASTM D 1831Roll Stability of Lubricating Grease ASTM D 2265Dropping Point of Lubricating Grease Over Wide-Temper
12、ature Range ASTM D 2266Wear Preventive Characteristics of Lubricating Grease (Four-Ball Method) ASTM D 2509Measurement of Load-Carrying Capacity of Lubricating Grease (Timken Method) ASTM D 2595Evaporation Loss of Lubricating Greases Over Wide-Temperature Range ASTM D 2596Measurement of Extreme-Pres
13、sure Properties of Lubricating Grease (Four-Ball Method) ASTMD 3336Test Method for Life of Lubricating Greases in Ball Bearings at Elevated Temperatures ASTM D 3337Test Method for Life and Torque of Lubricating Greases in Small Ball Bearings ASTM D 3527Life Performance of Automotive Wheel Bearing Gr
14、ease ASTM D 3704Test Method for Wear Preventive Properties of Lubricating Greases Using the (Falex) Block on Ring Test Machine in Oscillating Motion ASTM D 4048Test Method for Detection of Copper Corrosion from Lubricating Grease ASTM D 4049Test Method for Determining the Resistance of Lubricating G
15、rease to Water Spray ASTM D 4170Fretting Wear Protection by Lubricating Greases ASTM D 4289Compatibility of Lubricating Grease with Elastomers ASTM D 4290Leakage Tendencies of Automotive Wheel Bearing Grease Under Accelerated Conditions ASTM D 4425Standard Test Method for Oil Separation from Lubrica
16、ting Grease by Centrifuging (Koppers Method) ASTM D 4693Low-Temperature Torque of Greased-Lubricated Wheel Bearings ASTM D 4950Standard Classification and Specification for Automotive Service Greases ASTM D 5483Test Method for Oxidation Induction Time of Lubricating Greases by Pressure Differential
17、Scanning Calorimetry ASTM D 5706Test Method for Determining Extreme Pressure Properties of Lubricating Greases Using a High-Frequency, Linear-Oscillation (SRV) Test Machine ASTM D 5707Test Method for Measuring Friction and Wear Properties of Lubricating Grease Using a High-Frequency, Linear-Oscillat
18、ion (SRV) Test Machine ASTM D 5969Test Method for Corrosion-Preventive Properties of Lubricating Greases in Presence of Dilute Synthetic Sea Water Environments ASTM D 6138Test Method for Determination of Corrosion Preventive Properties under Dynamic Wet Conditions (Emcor Test) SAE J2695 Issued AUG20
19、05 - 3 - ASTM D 6184Test Method for Oil Separation from Lubricating Grease (Conical Sieve Method) ASTM D 6185Practice for Evaluating Compatibility of Binary Mixtures of Lubricating Greases ASTM MNL-1Manual on Significant Petroleum Tests (Sixth Edition) 2.1.3 NLGI PUBLICATIONS Available from NLGI, 46
20、35 Wyandotte Street, Kansas City, MO 64112, USA. NLGI Recommended Practice for Grease Lubricated Truck Wheel Bearings NLGI Lubricating Grease Guide 2.1.4 ELGI PUBLICATIONS Available from the European Lubricating Grease Institute, Hemonylaan 26, 1074 BJ Amsterdam, The Netherlands. “The Oil Separation
21、 Handbook,” Miller, D., 2003 “The Rheology of Lubricating Grease,” Balan, C. ed., 2000 2.1.5 TECHNOLOGY AND MAINTENANCE COUNCIL PUBLICATIONS Available from the American Trucking Association, 2200 Mill Road, Alexandria, VA 22314-4677, USA. TMC Recommended Practice 618Wheel Bearing Adjustment TMC Reco
22、mmended Practice 622Wheel Seal and Bearing Removal, Installation and Maintenance TMC Recommended Practice 631ARecommendations for Wheel End Lubrication 3. Definition of Lubricating Grease A lubricating grease is a solid to semifluid mixture of a liquid lubricant and a thickening agent. Additives to
23、impart special properties or performance characteristics may be incorporated. The liquid component may be a mineral (petroleum) oil or a synthetic fluid; the thickener may be a metallic soap or soaps or a nonsoap substance such as an organophilic modified clay, a urea compound, carbon black, or othe
24、r material. The viscosity of the fluid, the thickener concentration, and the chemical nature of the thickener can vary widely. The properties of the finished grease are influenced by the manufacturing process as well as by the materials used. 4. Basic Performance Requirements Greases are most often
25、used instead of fluids where a lubricant is required to maintain its original position in a mechanism, especially where opportunities for frequent relubrication may be limited or economically unjustifiable. This requirement may be due to the physical configuration of the mechanism, the type of motio
26、n, the type of sealing, or to the need for the lubricant to perform all or part of any sealing function in the prevention of lubricant loss or the entrance of contaminants. Because of their essentially solid nature, greases do not perform the cooling and cleaning functions associated with the use of
27、 a fluid lubricant. With these exceptions, greases are expected to accomplish all other functions of fluid lubricants. A satisfactory grease for a given application is expected to: SAE J2695 Issued AUG2005 - 4 - a. Provide adequate lubrication to reduce friction and to prevent harmful wear of mating
28、 components b. Protect against corrosion. c. Act as a seal to prevent entry of dirt and water. d. Resist leakage, dripping, or undesirable throw off from the lubricated surfaces. e. Resist objectionable change in structure or consistency with mechanical working (in the mechanism) during prolonged se
29、rvice. f. Not stiffen excessively to cause undue resistance to motion in cold weather. g. Have physical characteristics suitable for the method of application. h. Be compatible with elastomer seals and other materials of construction in the lubricated portion of the mechanism. i. Tolerate some degre
30、e of contamination, such as moisture, without loss of significant characteristics. j. Have suitable oxidation and thermal stability for the intended application. k. Prevent the premature initiation of rolling contact fatigue (allow extended life). 5. Properties of Greases 5.1 Consistency A measure o
31、f relative hardness. This property is commonly expressed in terms of the ASTM penetration or NLGI consistency number. The ASTM penetration is a numerical statement of the actual penetration of the grease sample, in tenths of a millimeter, by a standard test cone under stated conditions. The higher t
32、he penetration value: the softer the grease. The NLGI, formerly known as the National Lubricating Grease Institute, classifies greases according to their ASTM penetration as shown in Table 1. The consistency of a grease is an important factor in its ability to lubricate, seal, remain in place, and t
33、o the methods and ease by which it can be dispensed and applied. Most truck greases are in the NLGI No. 1, 2, or 3 range, that is, ranging from soft to medium consistency. Greases recommended for use in wheel end bearings and automatic or central lubricating systems will likely be one of the softer
34、NLGI grades such as 00 or 0. The NLGI grade is an indication of consistency only and should not be interpreted as level of performance. 5.2 Texture and Structure The appearance and feel of greases. A grease may be described as smooth, buttery, fibrous, long- or short-fibered, stringy, tacky, etc. Th
35、ese characteristics are influenced by the viscosity of the fluid, type of thickener, proportion of each of these components, presence of certain additives, and process of manufacture. There are no standard test methods for quantitative definitions of these properties. Texture and structure are facto
36、rs in the adhesiveness and ease of handling of a grease. 5.3 Structural Stability The ability of a grease to retain its as-manufactured consistency and texture despite age, temperature, mechanical working, and other influences, or its ability to return to its original state when a transient influenc
37、e is removed. SAE J2695 Issued AUG2005 - 5 - TABLE 1NLGI CONSISTENCY NUMBER NLGI Consistency No. ASTM Worked (60 Strokes) Penetration at 25 C (77 F) Tenths of a Millimeter(1)000 445 to 475 00 400 to 430 0 355 to 385 1 310 to 340 2 265 to 295 3 220 to 250 4 175 to 205 5 130 to 160 6 85 to 115 1. ASTM
38、 D 217 Cone Penetration of Lubricating Grease. 5.4 Mechanical Stability The resistance of a grease to permanent changes in consistency due to the continuous application of shearing forces. The stability of a grease is important to its ability to provide adequate lubrication and sealing and to remain
39、 properly in place during use. 5.5 Apparent Viscosity The ratio of shear stress to rate of shear at a stated temperature and shear rate. Grease is by nature a non-Newtonian material. Therefore, the usual concept of viscosity valid for simple fluids (that is, internal resistance to flow) is not entir
40、ely applicable. The ratio of shear stress to shear rate varies as the shear rate changes. The apparent viscosity of most greases decreases with increase of either temperature or shear rate. The applied shear rate or applied shear stress needs to be included when the apparent viscosity is reported. T
41、he apparent viscosity greatly influences the ease of handling, dispensing and flow characteristics of a grease. 5.6 Dropping Point The elevated temperature at which the grease generally passes from a solid to a liquid state or rapidly separates base fluid, and flows through an orifice under standard
42、 test conditions. The dropping point is incorrectly regarded by some as establishing the maximum temperature for acceptable use. Performance at high temperature also depends on other factors such as duration of exposure, evaporation and oxidation resistance, and the design of the lubricated mechanis
43、m. 5.7 Oxidation Resistance The resistance to chemical deterioration in storage and in service caused by exposure to air. It depends on the stability of the individual grease components, and can be improved by use of antioxidants. Oxidation resistance is important wherever long storage or service li
44、fe is required or where high temperatures prevail even for short periods. SAE J2695 Issued AUG2005 - 6 - 5.8 Protection Against Friction and Wear A protection greatly influenced by the viscosity and type of the fluid component and by grease structural and consistency characteristics. This performanc
45、e characteristic can be altered by use of additives. 5.9 Protection Against Corrosion A protection of ferrous components achieved primarily by the inclusion of suitable additives in the grease. The effectiveness of the protection is influenced also by the chemical and physical properties, such as in
46、teractions with other additives, consistency and base oil viscosity (both of which will determine how effectively the grease will seal out corrosive and other undesirable material), and the interaction with water. The effect of water on the grease can be significant. Some greases are water resistant
47、 or waterproof, which means that they resist the washing effect of water and do not absorb it to any significant extent. Other greases can absorb varying amounts of water without appreciable damage to their structure or consistency, and may provide better rust protection than waterproof greases whic
48、h can permit the accumulation of free water in bearings. 5.10 Bleeding or Oil Separation The separation of liquid lubricant from a grease. Slight bleeding is regarded as desirable by some as indicative of good lubricating ability in rolling element bearings. It also helps the grease to flow through
49、pipes in centralized systems by lubricating the pipe walls. 5.11 Color A superficial grease property without performance significance. 5.12 Flow There is, of course, the problem of getting grease to the bearings to be lubricated. Certain terms, by no means of strict, rigid interpretation, are used to describe the factors involved: feedability, pumpability, and dispensability. 5.12.1 FEEDABILITY OR SLUMPABILITY The ability to flow to the suction of the grease-dispensing equipment or mechanism to be lubricated. 5.12.2 PUMPABILITY T
