... ,4~5L/min6. duty circle: 80%7. TX-15A auto-control function of the timing: heating time, holding time, ... adjustable heating, insulating power and time, will help provide high quality of the repetitive heating and simplify workers to operate; ... small crank shaft pins, rocker, and other accessories high frequency hardening machine.hardware tools high-frequency hardening heat treatment, for example: vice, ...