| 摘要 |
PURPOSE:To produce a composite welding wire rod having good quality by supplying flux or metallic powder, interposing a shielding member which isolates the powder and a weld zone and welding the weld zone in the stage of bending a long-sized metallic strip in the transverse direction and forming the metallic pipe. CONSTITUTION:A metallic strip 20 wound on a spool 14 enters the spacing between forming rolls 28 through a guide roll 22 and a straightener roll 27. The strip 29 is bent at both ends with the rolls 28 and is further bent deeper with a forming roll 29, whereafter the strip is bent to a U shape with a forming roll 30. The flux or metallic powder 36 in a hopper 34 is supplied to the U shaped part through a valve 35. A belt-like shielding member 39 wound on a spool 15 is accepted in this state to the upper part of the powder, and the strip is bent to a circular shape with a forming roll 32. The clearance in both end parts is press-welded with a rolling roll 33, whereby said parts are welded. |
