... 380V 50-60HZ Oscillation frequency :12-25KHZ Induction heating machine,induction heating equipment,induction heating furnace.How to select the frequency of induction ... 2,heat treatment, shaft, gear, quenching and annealing stainless steel products and put quenching as an example, The shall lower ... the higher of the frequency. The deeper of the quenching layer. the lower of the frequency. Such as: ...