... .1.3 mining tools, welding, such as "one" bits, pillar gear drill bits, dovetail coal drill bits, drill rods riveting, all ... pin, wheel, camshaft, valves, all kinds of rocker arm, rocker shaft; transmission of various gears, spline shafts, drive axle, a variety ... pump rotor on a variety of valves for the shaft, the gear pump gear, etc. quenching.3.5 Heat treatment of metal parts ...