MAKING METHOD OF REMELTING-HARDENING TREATMENT AND DEVICE

摘要

The method and appts. relate to remelt-hardening of the valve drive surface of a cam. A heating torch is directing onto the surface of the cam which is axially reciprocated relative to the torch and is simultaneously rotated about its axis. Control devices are provided which allow the conditions of the hardening process to be altered for a predetermined region of the cam surface. Pref. the rotational speed is reduced approx. by 25 per cent when the predetermined part of the surface passes the heating jet. This part corresponds to a central angle from 20-60 degrees measured from the cam vertex in clockwise and anti-clockwise directions. USE/ADVANTAGE - Used e.g. in the motor industry. It allows a hardened layer of desired thickness to be uniformly produced over the entire cam circumference.