Thermally Activated Seizure of Angular Contact Bearings

Abstract

Equations have been developed relating friction-power to bearing element temperatures for the particular case of prelubricated or lightly lubricated ball bearings. An expression is derived for the change in relative dimensions of an angular contact bearing, as determined by the temperature gradient across the bearing. A second expression is found for the accommodation of the bearing to expansion, this accommodation resulting from elastic deformation and changes in contact angles. A comparison of these relationships reveals that unstable operating conditions may occur and lead to sudden uncontrollable increases in contact loads. These regions of unstable operation may occur as a result of lubricant degradation or bearing wear, as well as combinations of operating speed and housing dimensions.