Rotary metering valve assembly and method of modifying contact surface for reducing gauge wringing

摘要

A rotary metering valve assembly includes a stationary body plate having a first contact surface. Also included is a valve plate having a second contact surface disposed in contact with the first contact surface of the stationary body plate, wherein the valve plate is configured to rotate relative to the stationary body plate. At least one of the first contact surface and the second contact surface comprises a surface flatness of less than about 2.4 μm (about 93 μin) and a surface roughness of at least about 0.2 μm (about 8 μin).