In addition, the multi-tap inductor is very much effective for the surface treatment of the special quenched product, such as the traveling wheel of the gantry crane.

For this reason, special inductor and fixture have been designed and the heat treatment problem of the reverse fork has been successfully solved by double high frequency quenching.

Based on main chain spocket of shearers, the paper describes special requirement of reasonable high frequency quench, quench technology, structure and technology parameter of the inductor.