Sliding Contact PM212 Bearings for Service to 700°C

Abstract

Cylindrical, sliding contact bearings made entirely of the self-lubricating powder metallurgy composite (PM212) or of superalloy shells lined with clad PM212 were tested in an oscillating mode at temperatures from 25° to 700°C. Tests of 100-hour duration or longer were conducted with the journal oscillating ± 15° at a frequency of 42 cycles/min and at a bearing unit load of 3.45 MPa (500 psi). Shorter duration tests at various unit loads up to 24.2 MPa (3500 psi) were also conducted. In comparison tests, bearings lubricated with PM212 had lower friction and superior antiwear characteristics compared to the baseline, unlubricated, superalloy bearings. No galling of PM212-lubricated bearings occurred, while severe surface damage including galling occurred, especially at high loads, during the baseline tests. A heat treatment procedure, which dimensionally stabilizes PM212 and thereby minimizes clearance changes during high temperature bearing operation, is described.

Presented at the 52nd Annual Meeting in Kansas City, Missouri May 18–22, 1997

KEY WORDS:

• Composite Bearing
• Self-Lubricating Bearings
• Solid Lubricated Bearings
• Journal Bearings
• High Temperatures

Notes

Presented at the 52nd Annual Meeting in Kansas City, Missouri May 18–22, 1997