THICK, LARGE-SIZED STRAIGHT UOE STEEL PIPE SATISFYING REQUEST FOR STRICT TOUGHNESS, AND PRODUCTION METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a thick, large-sized straight UOE steel pipe which satisfies request for strict inside-outside toughness, and to provide a production method therefor, with respect to a both side one layer submerged arc welding method for a thick, high toughness UOE steel pipe having a plate thickness of ≥30 mm, by establishing an effective submerged arc welding technique for preventing the reheat embrittlement of an inside weld metal caused by outside welding.;SOLUTION: The composition of a base metal 1 is limited to a specified range. Further, the compositions (particularly, the contents of Mo and B) in an inside weld metal 2 subjected to reheat by outside welding and in an outside weld metal 3 subjected to no reheat, and Pcm are limited to respective specified ranges.;COPYRIGHT: (C)2004,JPO