| 摘要 |
The invention relates to a roll stand for rolling metal strips, having a hydraulic adjusting device (10) and a hydraulic counterbalancing device (8, 9). Both the adjusting device and the counterbalancing device are controlled as regards pressure. Whereas, during rolling with normal force, the control device (R2) assigned to the counterbalancing device (8, 9) is controlled in such a way that only the weight of the upper rolls is compensated, during re-rolling with a rolling force which is only a fraction of the normal rolling force the adjusting device exerts a constant rolling force somewhat greater than the rolling force required for re-rolling, while the counterbalancing device produces a counterforce which compensates both the weight of the upper rolls and that portion of the force exerted by the adjusting device (10) which exceeds the rolling force. By virtue of the sensitivity of the control device for the counterbalancing device and of the small hydraulic control elements of the counterbalancing device, it is possible in such a roll stand to execute significantly smaller adjusting steps in the elimination of a deviation than is the case with the adjusting device and the control device assigned to it. <IMAGE>
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