| 摘要 |
<p>A method for heat treatment of an electric resistance welded steel pipe, which can improve hydrogen induced cracking resistance and low temperature toughness by performing a simple heat treatment process of heating the preheated welded portion of the welded steel pipe after preheating a welded portion of a welded steel pipe manufactured by a high frequency electric resistance welding method, is provided. A method for heat treatment of an electric resistance welded steel pipe comprises the steps of: continuously forming hot rolled steel sheets into steel pipes(10); manufacturing an electric resistance welded steel pipe(13) by welding the formed steel pipes by a high frequency electric resistance welding method; preheating a welded portion of the electric resistance welded steel pipe; and heating the preheated welded portion of the electric resistance welded steel pipe at a temperature higher than the preheating temperature. The preheating step and the heating step of the welded portion of the electric resistance welded steel pipe are continuously performed by post seam annealers(14,15). The method further comprises the step of air-cooling the heated welded portion after performing the step of heating the preheated welded portion of the electric resistance welded steel pipe.</p> |
