Estimate of Surface Temperatures During Rolling Contact

Abstract

Temperature has been shown to be a key factor in the performance of rolling and sliding contacts. In normal bearing operation, contact areas on the bearing ball (or roller) and race are briefly heated due to ball or roller slip then cooled from convection to the surrounding medium. After numerous repetitive heating and cooling cycles, the bearing elements attain a steady state temperature that is dependent upon the heat input and the surrounding convective conditions. This paper examines the temperature profile in a rolling element using two approaches. The first approach involves a discrete step-by-step computation of the heating and cooling that occurs during a typical cycle under various conditions of heat input and convection conditions. Steady-state conditions are predicted by extending this repetitive process over many cycles. The second approach assumes that the heating and cooling occurs over the entire ball or roller track area after steady state is achieved. The results of both approaches are compared.