The Behaviour of Oil Lubricated Angular Contact Bearings Operating at Slow Speed

摘要

Vacuum tests were performed in order to determine the wear and torque of oil lubricated bearings operating at a speed corresponding to the boundary lubrication regime. The predominant form of damage on the races and balls is micropitting, partly caused by repeated identation of the steel surface by small, hard features. The scale of damage is small and has no significant effect on the torque characteristics. There should be no deterioration of the bearings in reaction wheels operating down to zero speed. The amount and type of damage changes very little with the type of oil used so that the choice of lubricant for variable speed bearings in spacecraft applications can be made on the basis of vapor pressure and viscosity, without regard to boundary lubricating properties.