The Wear of a Piston–Sleeve Friction Pair in Axial-Piston Pumps under the Conditions of Water-Contaminated Lubricating Oil

Workbench testing results are presented for axial piston pumps at a water content in oil up to 3%. It is shown that the wear rate of the pump pistons depends on the water content mainly according to a logarithmic law and retains a tendency to increase with an increase in the water content over 3%. The friction surface roughness of the piston depends on the water content in oil according to a power law, reaching a constant value at a water content over 2.5%. It has been found that the wear rate of the pistons decreases with increasing pressure in the hydraulic system.