To obtain drawing force required to a tube making method using a forming die for drawing a metallic strip into a cylindrical shape by circling endless-shaped rubber belts which are pressed against a welded tube stock from both sides.
The metallic welded tube is manufactured by drawing the metallic strip P0 with the forming die 1 and butt-welding both end parts in the width direction of the metallic strip P1 into a cylindrical shape. A take-off device 7 provided with a pair of the endless-shaped rubber belts 13, 13 is arranged on the downstream side of a welder 2 and the endless-shaped rubber belts 13, 13 which are pressed against the outside surface of the welded tube stock P2 from both sides along caterpillars are circled so as to impart fixed drawing force to the welded tube stock P2. Before the tube stock is drawn with the take-off device 7, the diameter of the welded tube stock P2 may be reduced in a sizing stand 5.
INOUE SHOJI
KAMODA MATSUICHI
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