Test Methods and Results of a Study of Greases for Use in Roto-Launch Valve Lubrication

摘要

The extended use of a MIL-G-23549 grease for lubrication of a roto-launch valve maintained at a temperature of 700 F caused a significant lubrication problem. This was brought about by decomposition of the grease into a solid mixture of molybdenum disulfide and clay which would clog grease lines in the vicinity of the valve. As an approach to this problem, several alternate grease formulations capable of providing lubrication under high load conditions were evaluated for their tendency to decompose at high temperatures. Testing was done by measuring the adhesion of grease residues to a steel surface and by measuring the amount of pressure required to force grease through a test rig maintained at 700 F. These studies indicated that the use of alkly-urea thickeners in place of clay thickeners decreases the tendency of a grease to clog grease lines under high temperature conditions. (Author)