| 摘要 |
PURPOSE:To fix a pipe diameter and to reduce a deviation at a welded place by measuring the deviation in the amount of overlap of steel strip immediately before resistance welding and controlling the approach angle on the approch side to a forming stand of the steel strip in accordance with the deviation. CONSTITUTION:A steel sheet S is flattened by a leveler 3, passed through a side reamer 4, a groove shape is made by a beveling device 5 to send the steel sheet to a forming stand 6. A lap sensor 10 measures the amount of overlap of a welding part of the pipe P at a resistance welding point 7 and an approach angle to a forming stand 6 of the steel sheet S. In accordance with detected values of the lap sensor 10, difference between right and left rolling forces of a delivery roll 13, steering of a forming roll 11, an approach angle alpha to the forming stand 6, etc., are adjusted. The inner and outer surfaces are welded at an outer surface welding point 8 and the inner surface welding point 9 to obtain the pipe P. A welding gap can be adjusted easily and the amount of deviation on the pipe manufacturing side is small. |
