| High-pressure axial piston pump works under the conditions of high speed and pressure.When the oil film lose efficacy on the surface of contact appears,condition turns to dry friction,which causes serious wear.Material Matching of the components and opening surface texture have important effects on the abrasion resistance of slipper pair.This thesis focuses on the effect of material matching to the performance of dry friction of the slipper pair in axial piston pump under high pressure and the effect of surface micro-pits to oil film performance as well as the performance of dry friction of slipper pair in axial piston pump under high pressure.The research is mainly undertook from the following aspects:(1)The stress and temperature of contact surface of the slipper pair for 35 MPa high pressure axial piston pump with different material matching and the same operating condition are analyzed by the finite element analysis method.The following facts are revealed: favorable contact stress distribution can be acquired if selecting sliding shoes with appropriate elasticity modulus,low poisson ratio and density to match swash plate material with low poison ratio and high elasticity modulus;Choosing swash plate material with higher density,specific heat and thermal conductivity as well as sliding shoes with higher thermal conductivity and lower density,specific heat can signally improve the temperature rise on the bottom of sliding shoes.(2)Slippers of three different materials(1Cr18Ni9Ti?ZQSn10-1?ZQAl10-4-4)and swash plates of two different materials(38Cr Mo Al A?45# steel)are selected to conduct orthogonal test.An Independent development and improvement FAIAX6 friction-abrasion testing machine is used to experiment.The following facts are revealed: the match of ZQSn10-1 and 38 Cr Mo Al A provides the lowest Contact stress;the match of ZQSn10-1and 45# steel provides the smallest temperature rise.(3)In order to grasp the change law of the carry capacity of oil film and the temperature rise when the parameters of surface texture on the sliding shoe vary,three different surface textures are chosen to establish at the bottom of the sliding shoe.Based on the hydrostatic lubrication technique of slipper pair,the Fluent toolbox of ANSYS software is used to study the influence of different surface texture,area rate,and depth-diameter 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 following facts are revealed: Inverted triangular section provides the best carrying capacity of oil film.The average interface pressure increases 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 depth-diameter ratio.Excellent oil film performance can be acquired if inclining the underside of texture,optimizing the surface shape and choosing the larger depth-diameter ratio.(4)Four different surface textures are chosen to establish at the bottom of the sliding shoe.Control the parameters of surface texture on the sliding shoe,and use the Workbench finite analysis software to study the influence of different texture,area rate,and depth-diameter ratio to the pressure and temperature changes of the performance of dry friction for the slipper pair for 35 MPa high pressure axial piston pump under the same working condition.The following facts are revealed: The surface maximum contact stress is the smallest when the area ratio of the cylindrical texture is around 24% and the depth ratio is around 0.2.When the area rate continues to increase,its value does not obviously increase with the area ratio,but it increases obviously with the increase of the depth ratio.Triangle texture can effectively control the temperature rise,and it reaches the minimum when the depth ratio is around 0.2.Different shape of texture has the optimum solution of area rate and depth-diameter ratio for temperature control and reduction of pressure on the surface. |
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