Air-Cooled Induction Heating Solution for Heat Treatment of P91 Grade Steel in Welding Applications

To have long operating life and to withstand high temperature and pressure of steam, now a days, the standard material used in power industry is the P91 Grade steel. It has high creep resistance. In a fabrication process when arc welding is used for joining this material the high energy density of arc heat makes strong influence on its microstructure. Moreover, the prospect of hydrogen cracking increases if pre-heating is not properly done. Therefore, for long term quality of P91 Grade steel, detailed heat treatment operation must be performed before and after the welding. For heat treatment operations, the induction heating method is ideally suitable. This article proposes to use air-cooled system to improve the efficiency of power delivery to the requisite area of pipe in high power applications.