... of machine parts heattreating(quenching,anneal, temper,normalizing),braze welding,smelting,copper bar High frequency induction heating machine:frequency ... from20 to 80KHZ Application: all classes of machine parts heattreating(quenching,anneal, ... 9. copper bar annealing, wire annealing 10. machine tool guideways gear,chain wheel quenching 11.elbow ...