... and gear rings.2. Surface hardening of spline shafts, bent axles, camshafts, drive shafts, semiaxes, fork shafts and optical axes, maximally quench to ... , crank pins, chain wheels, valves, rocker arms, rockshafts, small shafts and shifting forks.5. High frequency hardening of various gears ... 7. Quenching of rotors of plunger and rotor pumps, reversing shafts of valves, gears of gear pumps, and so on. ...