Calculation Methods For Spherical Plain Bearings

Spherical plain bearings (SBPs) have two "fitting" spherical contact surfaces, a type of contact known as coordinated contact. Calculation methods for the mechanical properties of SBPs are crucial for their structural design and wear analysis. Calculating contact pressure on coordinated surfaces is a complex problem. The existing Hertz model, limited to elastic half-spaces, cannot be used to calculate the pressure distribution on spherical coordinated contacts. A unified spherical contact model, the Fang model, effectively addresses the issue of contact pressure distribution on spherical surfaces with small deformations. This model is applicable to both non-conforming and coordinated contacts. However, the contact area of a SBP is not a perfect sphere, so the calculation of its contact pressure distribution requires further calculation based on the perfect spherical coordinated contact model. Furthermore, free boundary effects can occur during the operation of SBPs, impacting their application. This free boundary effect results in concentrated contact pressure and a large pressure gradient at the edge of the SBP outer ring.