Classification and Standards
Jointly developed by ASTM International, the National Lubricating Grease Institute (NLGI) and SAE International, standard ASTM D4950 “standard classification and specification for automotive service greases” was first published in 1989 by ASTM International. It categorizes greases suitable for the lubrication of chassis components and wheel bearings of vehicles, based on performance requirements, using codes adopted from the NLGI's “chassis and wheel bearing service classification system”:
- LA and LB: chassis lubricants (suitability up to mild and severe duty respectively)
- GA, GB and GC: wheel-bearings (suitability up to mild, moderate and severe duty respectively)
A given performance category may include greases of different consistencies.
The measure of the consistency of grease is commonly expressed by its NLGI consistency number.
The main elements of standard ATSM D4950 and NLGI's consistency classification are reproduced and described in standard SAE J310 “automotive lubricating greases” published by SAE International.
Standard ISO 6743-9 “lubricants, industrial oils and related products (class L) — classification — part 9: family X (greases)”, first released in 1987 by the International Organization for Standardization, establishes a detailed classification of greases used for the lubrication of equipment, components of machines, vehicles, etc. It assigns a single multi-part code to each grease based on its operational properties (including temperature range, effects of water, load, etc.) and its NLGI consistency number.
Read more about this topic: Grease (lubricant)
Famous quotes containing the word standards:
“A generation which has passed through the shop has absorbed standards and ambitions which are not of those of spaciousness, and cannot get away from them. Everything with them is done as though for sale, and they naturally have in view the greatest possible benefit, profit and that end of the stuff that will make the best show.”
—Alexander Herzen (1812–1870)