Abstract:Highpressure axial piston pump works under the condition of oil lubrication,the surface structure of the part has an important effect on the performance of oil film between the contact surfaces.Three different surface micropits,conical,cylindrical and square micro pits,were machined at the bottom of the sliding shoe,and the change law of the carry capacity of oil film and the temperature rise was investigated when the parameters of surface micro pit on the sliding shoe vary.Based on the hydrostatic lubrication technique of slipper pair,the finite element analysis method was used to study the influence of different micropit texture,area rate,and depthdiameter ratio to the pressure and temperature changes of oil film of the slipper pair for 35 MPa high pressure axial piston pump under the same working condition.The results show that the conical section at the bottom of the sliding shoe provides the best carrying capacity of oil film.The average interface pressure is increased evidently with the increase of the depth ratio within a certain range.Square surface has the minimum temperature rise under low area rate and high depthdiameter ratio.Excellent oil film performance can be acquired if inclining the underside of micropit,optimizing the surface shape and choosing the larger depthdiameter ratio.