Preliminary Evaluation of Greases to 600 F and Solid Lubricants to 1500 F in Ball Bearings

Abstract

A special apparatus designed for the evaluation of high temperature lubricants in 20 mm bore ball bearings is described. The results of bearing runs at temperatures up to 1500 F in air are reported. Of the greases evaluated, a fluorocarbon grease, provided bearing lubrication for longer times at 450 and 600 F than either polyphenyl ether or silicone greases thickened with dyes and/or MoS₂. Cobalt alloy ball bearings, lubricated either with barium fluoride-calcium fluoride coatings bonded to the cages or with porous metal cages impregnated with these fluorides, ran successfully at 1200 and 1500 F under a thrust load of 30 pounds and at a shaft speed of 5000 rpm.