Lubrication characteristics of the slipper–swash-plate interface in a swash-plate-type axial piston pump

An analytical approach based on a hydrodynamic lubrication model is presented to understand the bearing capacity, leakage, and friction moment of the slipper–swash-plate interface in a swash-plate-type axial piston pump. Furthermore, how the shaft speed, load pressure, and slipper attitude influence the lubrication performance of the interface is analyzed. The research shows that the slipper attitude has a significant effect on the pressure distribution. To improve the lubrication performance, a grooved sealing-land design is proposed, and the location and geometric parameters of the groove are analyzed. The results indicate that the optimal lubrication performance is achieved when the groove is 2.0–3.0 mm wide and 5–20 µm deep at its inner boundary.