... ,welding,forging,annealing and melting Intermediate frequency induction chain wheel hardening machineInduction hardening equipment:frequency about 40KHZ,smaller ... machinery parts, such as: all kinds of gear wheel, chain wheel, kinds of axis, pin.3. hardening the industrial ... as : bed guide way of machine tool.4. heat treatment pliers, spanner, screwdriver, drill, axe5. hardening pin, piston ring, ...