| 摘要 |
PURPOSE:To eliminate a degreasing stage and to enable manufacturing the thin walled metallic pipe free from flaws, by performing a plastic bending work through a floating roll having small diameter put on a gap between two cylindrical rolls rotating in the same direction. CONSTITUTION:An inlet side cylindrical roll 1 and outlet side cylindrical roll 2 are rotating in the same direction provided with the gap G. Floating on this gap G, the small diameter bending roll 3 performs the plastic bending of a metallic plate 4. A deflector roll 5 performs bending to return the curvature of the metallic plate 4 in the longitudinal direction to be zero. The metallic plate 4 is bent to be tubular by the cross directional residual stress generated through the plastic bending and return bending. A seam guide roll 6 performs the position controlling of the end edge of the metallic plate 4, after passing through the squeeze roll 7, the abutting part of the metallic plate 4 is welded by the welding toach 8 to be the metallic pipe. Since no lubricating is operated, the degreasing stage is eliminated. |
