An Investigation of the Impact of Micro Surface on the Cylinder Block/Valve Plate Interface Performance

Lubricating gaps are the primary source of energy dissipation in axial piston machines of swash plate-type. One of these lubricating gaps is designated as the cylinder block/valve plate interface, and is one of the most critical design elements for this type of positive displacement machine. In the past, extensive work has been done at Maha Fluid Power Research Center both to model this interface and to study the effects of micro-surface shaping on the valve plate. This paper presents a more in-depth investigation into optimizing valve plate micro-surface shaping (both by altering the number and amplitude of waves) in order to achieve a fluid film thickness that compromises between leakage and torque loss, minimizes power loss in the cylinder block/valve plate interface, and maximizes machine efficiency.