STRESS-RELIEF HEAT TREATMENT APPARATUS

A stress-relief heat treatment apparatus according to the present invention for stress-relief heat-treating a rail which is welded includes an induction heating coil, and the induction heating coil is arranged at a lateral lace of a web of the rail while being separated from a welding center of the rail by 20 mm to 300 mm in a longitudinal direction of the rail. The stress-relief heat treatment apparatus may include a plurality of the induction heating coils, and the induction heating coils may be arranged at both sides of the welding center. The stress-relief heat treatment apparatus may include a plurality of the induction heating coils, an axial direction of the induction heating coil may be vertical to a lateral surface of the rail and a plurality of the induction heating coils, of which distances from the welding center along the longitudinal direction of the rail are the same, may be arranged to cover a whole circumference of the rail while being separated from each other.