Abstract:To improve the lubrication characteristic of slipper pair, the thermal clearance formula of slipper pair was proposed based on thermodynamic principles considering the heat conduction relationship between slipper pair and oil film. The laws of effect of different cylinder pressure, cylinder speed and inlet oil temperature on thermal clearance of slipper pair were discussed. The results show that the thermal clearance of slipper is inversely proportional to the linear expansion and thermal conductivity of material, which reduces the resistance capacity of material to deformation and matching performance of friction pair. Thermal expansion of slipper and swashplate are caused by surface temperature, which remarkably reduces the thermal clearance of slipper pair, and is positively proportional to cylinder pressure, speed and inlet oil temperature. Therefore, the high linear expansion and thermal conductivity of material is used as slipper in order to reduce surface wear, which is just the opposite to material selection of swashplate.