| 摘要 |
<p>PROBLEM TO BE SOLVED: To smoothly control the elongation even when a line speed has become high by automatically operating tension between stands so that the measured elongation and a target elongation coincide, and gradually increasing the rolling down force of a rolling mill when the tension has increased to a prescribed value. SOLUTION: By installing circumferential speed sensors 11, 12 on bridle rolls 3, 4, and connecting them to an elongation percentage calculator 13, an actual elongation is obtained. The actual elongation and the target elongation are inputted in a subtracter 14. Its result is sent to an elongation controller 15, and proper tension between stands is determined. When detecting by limiters 22, 23 that a tension set value to be outputted from an adder 21 connected to the elongation percentage controller 15, does not exceed an upper limit, according to a tension set value to be determined from an initial set value and the output of the elongation percentage controller 15, a difference in circumferential speed necessary between rolling mills 1, 2 is determined by a tension controller 26. By adding the determined difference in circumferential speed to the circumferential speed of the rolling mill 2 by an adder 32, the circumferential speed command of the first rolling mill 1 is obtained.</p> |
