METHOD FOR MANUFACTURING ELECTRIC RESISTANCE WELDED TUBE HAVING EXCELLENT WELD CHARACTERISTIC

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electric resistance welded tube having excellent weld characteristic capable of maintaining excellent welding quality by adequately giving a tapered shape to an end of a plate (a strip) before the electric resistance welding when manufacturing the electric welded tube. SOLUTION: A strip 20 is rolled while restricting the thickness direction of the strip by a contour roll 3 before the roll forming, and a taper shape is given to an end on an upper surface side of the strip 20. At the same time, the taper shape is given to an end on a lower surface side of the strip 20 in a fin-pass rolling stand 4. COPYRIGHT: (C)2008,JPO&INPIT