New tools for estimating the fatigue life of rolling element bearing cages

Rolling element bearings (Or REB) are machine members that overtake loads through Hertzian stresses between their contacting components (e.g. the inner ring IR, rolling element WK and outer ring AR). To maintain the rolling elements WK at the right place, usually a separator, a cage or a spacer is used to allow the rolling element bearing to achieve its function adequately. The main load being overtaken by the rolling element themselves, the space does normally not see any heavy loads. Nevertheless, as the cage interact with its neightbours, some contact stresses, friction stresses and inertial stresses are acting on the cage during its motion leading to some given phenomenon. The current article intends to review the different stress situations, the phenomenon encountered and their mechanism, the potential failure modes (Volume fatigue, wear, cyclic deformation, ...) under which the cage or separator may damage itself and further fail. The evaluation of the stresses acting on the cage during its motion, even if of many less orders of magnitude as the Hertzian ones, request fine calculations methods and tools such as Caba3D, BearinX or FEA softwares. The article intends to show the modern computation methods and their uses in industry. A special focus is made on the fatigue resistance of the cage and the modern ways these stresses are apprehended and computed.