摘要 |
PROBLEM TO BE SOLVED: To provide a electric resistance welded tube for a low pressure container and its manufacturing method excellent in workability and productivity. SOLUTION: A steel tube stock is successively subjected to roll forming, an electric resistance welded tube for a low pressure container is constituted so as to be of a large diameter and to satisfy a condition of a specified value or lower for a ratio t/D of a thickness (t) and an outer diameter D. The steel tube stock subjected to rolling at a draft of 1-5% to shape correction, is successively roll formed with imparting a reduction of 2-4% in a forming initial stage, the electric resistance welded tube, which has a outer diameter of >=200 mm and a ratio t/D of a thickness (t) and an outer diameter of <=0.011, is manufactured.
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