Method of heat-treatment of welded pipe and apparatus therefor

摘要

In the method of heat-treatment of welded pipe having a reinforcement weld bead therealong by heating the pipe by using an induction heating device and then by cooling it, the bead which has just been heated by the induction heating device, is further heated by a bead heater to a temperature such that the temperature difference between the metal of the pipe and the bead is smaller than a temperature difference which will produce a bad influence on the quality of the pipe.