| 摘要 |
1290162 Automatic control of rolling BETHLEHEM STEEL CORP 14 Nov 1969 [18 Nov 1968] 55836/69 Heading G3R In a rolling mill, roll speed is automatically controlled by a loop detector to correct the tension and a delayed signal representative of thickness, computed from roll load and screwdown position, is compared with a reference signal so that any difference automatically controls screwdown to correct the thickness. In Fig. 1, a signal dependent on the size of a loop formed in a strip 11 passing between rolling mill stands 13, 15 is compared at 27 with a reference signal from a source 26 so that tension errors are corrected by automatic control of the speed of a motor 29 driving the rolls of stand 15. A signal dependent on rolling load from a load cell 33, modified for mill characteristics at 35, and a signal dependent on the position of screwdown 21 are combined at 39 to produce a signal, representative of strip thickness, which is compared with a reference signal from a source 40 so that thickness errors are corrected by automatic control of a screwdown motor 41. To prevent false correction of thickness during periods when the slower acting tension control is operating, all or part of the signal from load cell 33 is delayed by an adjustable resistance - capacity network 37. |
