... ceramic parts include, tube, rod, plate, disc, wafer, ring, seal, bearing, valves, pump plunger, beam, roller, shaft, screw, washer, sleeve, hunger, ... are used in a wide range of semiconductor, electronic, electrical, mechanical, chemical, automotive, textile and the other industrial engineering applications, ... .005Roughness 0.05Fit clearance0.005 99 alumina ceramic piston pump &alumina ceramic part