RESISTANCE WELDED TUBE EXCELLENT IN GROOVING CORROSION RESISTANCE, AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To manufacture a resistance welded tube capable of preventing the occurrence of grooving corrosion with certainly at a low cost while obviating the necessity of special component regulation and heat treatment. SOLUTION: This resistance welded tube excellent in grooving corrosion resistance has <=0.0010 wt.% solid-solution S content in a weld heat-affected zone. The resistance welded tube excellent in grooving corrosion resistance can be manufactured by using, at the time of manufacturing the resistance welded tube, a hot rolled steel plate containing <=0.010 wt.% S and >=0.01 wt.% Cu and applying cooling to the weld heat-affected zone after after resistance welding at <=100 deg.C/sec cooling rate from 1000 deg.C down to 700 deg.C.