Abstract:The bottom pivot of a hinged gate,as a hemispherical friction pair,operates underwater for a long time under low-speed and heavy-load conditions,which is prone to failure due to wear and tear.Traditional grease lubrication is prone to environmental pollution,while solid embedded lubrication is a more suitable lubrication method.In order to investigate the influence of different materials and bushing embedded structures on the tribological performance of the pivot friction pair,the experiments were experiments to obtain the mechanical properties of graphite-filled lubricating materials,as well as friction coefficients under varying conditions.Focusing on the bottom pivot of the Three Gorges hinged gate,two different bushing embedded structures with identical and variable aperture sizes were designed from both engineering and theoretical analysis perspectives.The contact stress of the spherical static contact and rotational operation states was calculated using finite element software,and the theoretical friction coefficients of smooth bushings,the bushings with uniform apertures,and the bushings with variable apertures were compared.The results show that from a stress perspective,graphite lubrication is superior to Thordon material lubrication under the same embedded structure.Under identical filling area conditions,the maximum equivalent stress of the three structures is in descending order of variable aperture structure, uniform aperture pore structure,and smooth structure.However,from both lubrication and theoretical friction coefficient perspectives,the performance of the variable aperture structure is the best,followed by the uniform aperture structure and smooth structure in order.Compared with the path with embedded holes,the bushing equivalent stress on the path without embedded holes is lower.Therefore,in practical applications,it is necessary to ensure that the mechanical bias direction aligns with the non-embedded hole region of the bushing to reduce stress concentration and improve lubrication performance.