Abstract:The curvature radius of gear was calculated according to the basic theory of differential geometry,and the entrainment velocity was calculated during facegear meshing process by the relative movement of the tooth surface.The isothermal elastohydrodynamic lubrication model of the facegear was established.The oil film thickness of the tooth surface was calculated through the FORTRAN language programming,and the influence of the pit diameter and depth on the film thickness was analyzed.The accuracy of theoretical calculation was verified by experiments.The results show that from the beginning of the facegear meshing process to disengagement,the film thickness is increased gradually along the meshing track.When the pit diameter of the tooth surface is from 50 μm to 200 μm,the oil film thickness is increased,and the optimum pit diameter is 100 μm.When the pit depth of the tooth surface is from 5 μm to 20 μm,the oil film thickness is increased,and the optimum depth is 10 μm.