| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a butt-welded steel pipe by which the top collapse of a steel pipe is prevented when performing the rotary straightening of the butt-welded steel pipe. SOLUTION: In the method of manufacturing the butt-welded steel pipe by which the rotary straightening of the bend, outside size and shape of the steel pipe 1 obtained by cutting is performed with a straightening machine after performing press contact and forge welding by heating the end parts of the steel strip up to a temperature less than the melting point while feeding a steel strip into a heating furnace continuously and forming it into a cylindrical shape, a pair of vertical rolls 5 which are nearly vertical to straightening rollers are installed between the inlet side guide 3 of the straightening machine and the straightening roller 2 and the steel pipe is passed between the rolls of the pair of the vertical rolls. COPYRIGHT: (C)2011,JPO&INPIT |
