Lubrication and scuffing failure of rib/roller end contacts in cylindrical roller bearings

Asperity temperatures of inclined rib/crowned roller end contacts in cylindrical roller bearings are studied for the scuffing failure using the partial-EHL method and a newly developed rough contact model.First, a simple model is formulated for the analysis of both asperity contact pressure and the temperature on purely longitudinal rough surfaces. The problems encountered by conventional asperity models are tackled here. Three roughness parameters are used in the model: r.m.s. roughness, autocorrelation length, and bearing area. Good agreement is found between present statistical model and deterministic analysis. Asperity contact and temperature model is then coupled with partial-EHL program to take into account lubricant hydrodynamic action on rough surfaces. Asperity temperatures calculated from the scuffing data obtained from a specially designed simulation machine are consistently in the range of 150-200...