| 摘要 |
PURPOSE:To obtain the steel pipe having the weld zone without defects and no bends by setting in advance the allowable width widening quantity per unit length of a steel strip and by making a pipe with removing the width widening part exceeding the allowable width widening quantity. CONSTITUTION:A control device 19 sets in advance the allowable width widening quantity per unit length of a steel strip 12. The measurement results of a steel strip length measuring device 20 and steel strip width measuring device 21 are transmitted to the control device 19 as well. The control deice 19 detects the width profile in the longitudinal direction of the steel strip 12 according to the measurement result and detects the remarkable width widening part exceeding the allowable width widening quantity of the steel strip 12. The control device 19 further drives a trimming device 22 to control and removes the remarkable width widening part. In case of having the locally remarkable width widening part in the longitudinal direction of the steel strip 12, the excess width widening part in the butt part being formed by both edges of the steel strip 12 is removed in advance and the gap against the inner face welding 13A and outer face welding 13B is optimized without giving any bend to a steel pipe 14.
|
