... , hardware tools, rigging, the hot upsetting of hot-rolled twist drill and so on, The longer of the workpieces diameter, the ... applicable UHF 100-250 KHz, high-frequency 1.0-1.5mm applicable 40-50 Khz high-frequency, super-audio1.5-2 ... IF 3, Welding, Welding head, lathe tool, reamer, milling cutter, drill bits, and stainless steel bottom of the pot, such as the ...