Theoretical and experimental research on the formation of lubrication film for slipper bearings of axial piston pumps

In order to improve the friction properties, the slipper bearings need to operate in the condition of full film lubrication. A friction dynamic model of slipper bearing was presented by coupling the hydrodynamic lubrication equation, oil film thickness equation, velocity equation of arbitrary point, flow quantity balance equations, force and moment equilibrium equations. An experiment modelling the slipper bearing device was designed and tested to provide experimental study. The two methods developed were used to investigate influences of rotating speed and pressure on the characteristics of the film including central film thickness, minimum film thickness and tilt directional angle. Both of the simulation results and test results show that, the film thickness increases with the rotating speed, but the increasing tendency turns smooth, at the same time, the film thickness decreases as the pressure increase. The slipper bearing often operates in the state of mixing lubrication at low rotating speed and high pressure condition.