... annealing,tempering,diathermy,metal smelting,welding of drill bits,saw blades,steel tubes and motor rotors... Energy saving high frequency ... like quenching, annealing, tempering, drill bit welding, saw blade welding, motor rotor welding, tungsten rod annealing as well as single ... tempering, diathermy, metal smelting, welding of drill bits, saw blades, steel tubes and motor rotors, as well as tungsten ...