DEVELOPMENT OF GAS-ENTRAINED POWDER LUBRICANTS FOR HIGH SPEED-AND HIGH-TEMPERATURE OPERATION OF SPUR GEARS

The feasibility of adapting powder lubricants to the operation of gears during relatively long periods of time under extreme environmental conditions was established. In addition to the lubricant study, parallel investigations were conducted on gear materials and methods of dispensing powder lubricants. Significant achievements of this program are listed below. 1 A pair of 5 DP spur gears, manufactured from M-50 tool steel, had operated for 98- 12 hours at a speed of 7400 rpm, load of 1000 pounds per linear inch of tooth face, and temperature cycled from room temperature to 900 degrees F. 2 Evaluations of fine-pitch 1214 DP superalloy and tool-alloy steel gears were conducted at speeds to 15,500 rpm, temperatures in excess of 1000 degrees F, and loads to 1000 pounds per linear inch of tooth face. 3 All high-temperature evaluations performed during this program used a graphite plus cadmium oxide powder mixture as the gear lubricant. An air carrier was used to deliver the powder to the gear set.