Mixed Lubrication Characteristics of Hydrostatic Spherical Bearings for Piston Pumps and Motors

Tribological characteristics of hydrostatic spherical bearings used in hydraulic piston pumps and motors are studied theoretically and experimentally in mixed and fluid film lubrication. The basic equations considering metallic contact are derived using the mixed lubrication model which is based on the asperity-contacting model and the mean flow model. The effects of surface roughness, supply pressure, load, rotational speed and the seat geometry on the eccentric ratio, fluid pressure distributions, asperity-contacting pressure, leakage flow rate and the power loss are examined. The theoretical results are compared with the experimental data and the good agreement is shown