公开(公告)号：JPH09239451A

公开(公告)日：1997-09-16

申请号：JP5311196

申请日：1996-03-11

Applicant: SUMITOMO METAL IND

Inventor： AISAKA SHINICHIRO ,  KUBOKI TAKASHI ,  TAKAI TAKASHI

IPC: B21D7/025

Abstract: PROBLEM TO BE SOLVED: To provide a device capable of bending a tube having a same outside diameter and different radius of curvature with a same tool and the cold bending method capable of obtaining a U tube having the least possible variance in a radius of curvature of bent part. SOLUTION: A tube clamp means 7 to fix/hold a tube P to be worked is mounted on a drive turning table 2 at a variable position, further, a tube support means 12 consisting of paired grooved roll group 125 to hold the tube P to be worked movable in the longitudinal direction and to control a tube feed out speed is arranged on fixed frame 3 arranged in row on the drive turning table 2. By coinciding a tube feed out speed by the tube support means 12 with a turning speed of the tube clamp means 7, bending is executed. By this method, the U tube having reduced variance in a radius of curvature of bent part is produced.