Regarding the increasing demand in seal lifetime and energy efficiency, a detailed microscopic simulation is necessary—as an addition to experimental investigations—to better understand and improve radial shaft seals. For this purpose, typically thermoelastohydrodynamic lubrication (TEHL) simulations are used. The published models range from rather simple elastohydrodynamic lubrication (EHL) models to very sophisticated TEHL models. Only very few models take into account the roughness or microstructure of both contact surfaces, though, since this would require the consideration of transient effects. In this article, a transient TEHL model for the contact of radial shaft seals is presented. Studies of the sealing contact are conducted, and the possibility of investigating shaft microstructuring is shown.
Cage not only separates the rolling elements but play an essential role of lubricant supplier in solid lubricated rolling bearings, thereby lubricating the rolling contacts. In such bearings, whose service life can be significantly extended by targeted cage wear, a better understanding and a reliable prediction of the wear is necessary in order to achieve a further increase in the service life. In order to predict wear and eventually their life-time is a complex phenomenon as it involves several transfer processes taking place in the rolling and sliding contacts. The lifespan of such bearings can be determined by performing numerous lifetime experiments. Global lifetime model for solid-lubricated rolling bearings does not exist so far like a conventional bearing life model. Therefore, a dynamic simulation strategy based on Adams multibody simulation environment to predict and model wear at cage pocket interface have been proposed. An incremental wear simulation approach based on Fleischer wear law is introduced. Uniform global wear of the cage pocket depending on the recalculation of cage geometry and converted frictional energy for each wear increment is calculated. Simulation results show good accordance with the experimental results. The importance and suitability of such a wear simulation approach will be enunciated in this paper.