Chittick, Martin B.
Manager, The Pure Oil Co., Chicago, Ill.
Pages: 8 Published: Jan 1940
The American Society for Testing Materials has denned petroleum grease in the Standard Definitions of Terms Relating to Petroleum (A.S.T.M. Designation: D 288-39) as follows: “A semisolid or solid combination of a petroleum product and a soap or a mixture of soaps, with or without fillers, suitable for certain types of lubrication.” The scope of this paper is primarily limited to products falling within the limits of this definition, the trend in research in the field of lubricating greases, and the various physical and chemical tests that have been developed for application to control the quality of greases, as well as predicting their service performance. Due to the fact that the term “lubricating grease” is a generic one, a sharp line of demarcation between certain classes of lubricants is impossible. It is for this reason that the above definition, while definitely a progressive step, leaves much to be desired. Take, for a typical example, the so-called extreme-pressure lubricants, which fall into two general classes. In the first class can be placed the lead soap—active sulfur type of extreme pressure lubricant, which falls within the definition of a petroleum lubricating grease. As against this type of lubricant, we have the extreme-pressure lubricant consisting of mineral oil with an organic additive agent, which, in general is commercially considered as a grease, yet does not fall within the scope of the definition.
Paper ID: STP47839S