HEAT TREATMENT METHOD FOR RING-SHAPED MEMBER AND HEAT TREATMENT EQUIPMENT FOR RING-SHAPED MEMBER

摘要

In a heating step (S1) of inductively heating a steel ring-shaped member (R) to a target temperature, a plurality of ring-shaped members (R) retained by a retaining unit (3) coaxially with each other are caused to sequentially pass through an opposing region of a first heating coil (21) having a constant output, and through an opposing region of a second heating coil (22) having a variable output and being arranged coaxially with the first heating coil (21) on an exit side of the first heating coil (21). Thus, the plurality of ring-shaped members (R) are sequentially and inductively heated to the target temperature.