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Strip material is fed to a reduction rolling mill by a steering device in the form of a pinch roll stand comprising pinch rolls to which strip gripping forces are applied by hydraulic cylinder units located at the ends of the pinch rolls. A reduction mill is similarly provided with a pair of hydraul

Strip material is fed to a reduction rolling mill by a steering device in the form of a pinch roll stand comprising pinch rolls to which strip gripping forces are applied by hydraulic cylinder units located at the ends of the pinch rolls. A reduction mill is similarly provided with a pair of hydraulic cylinder units which are independently operable to vary the pressure applied by the reduction rolls across the strip. Sensors sense the position of the strip at a first location in advance of the pinch rolls and a second location in advance of the rolling mill. This output of sensors is fed to a controller which controls operation of both sets of hydraulic cylinder units to steer the strip.

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1. A method of rolling strip material comprising passing the strip through a steering device into a rolling mill having a pair of strip reduction rolls extending laterally of the strip feed direction, the steering device being operable to steer the strip as it passes to the rolling mill, applying st

1. A method of rolling strip material comprising passing the strip through a steering device into a rolling mill having a pair of strip reduction rolls extending laterally of the strip feed direction, the steering device being operable to steer the strip as it passes to the rolling mill, applying strip reduction squeezing forces to the reduction rolls at positions spaced apart longitudinally across those rolls monitoring the position of the strip at a first location in the vicinity of the steering device and at a second location in the vicinity of the rolling mill, and operating the steeling device and varying the relative squeezing forces on the reduction rolls at the spaced positions in response to observed positions of the strip at said first and second locations. 2. The method as claimed in claim 1, wherein the steering device is operated in response to the observed position of the strip at said first location. 3. The method as claimed in claim 1, wherein variation of the relative squeezing forces applied to the reduction rolls is dependent on observed positions of the strips at both said first and second locations. 4. The method as claimed in claim 3, comprising generating a first control signal dependent on the observed strip position at said first location, generating a second control signal dependent on the observed strip position at said second location, operating the steeling device to steer the strip in response to the first control signal, applying a time lag to the first control signal corresponding to a function of the time of strip travel between said first and second locations, making a comparison between the lagged first control signal and the second control signal, and varying the relative squeezing forces on the reduction rolls at the spaced positions in response to the outcome of that comparison. 5. The method as claimed in claim 4, wherein the second control signal is generated from a comparison of the observed strip position at said second location with a desired or set position for that location. 6. The method as claimed in claim 1, wherein the steering device is operated in response to a control signal produced by comparing the observed position of the strip at said first location with a desired or set position. 7. The method as claimed in claim 6, wherein variation of the relative squeezing forces applied to the reduction rolls is controlled by a further control signal dependent on observed strip positions at both said first and second locations when compared with desired or set positions at those locations to effect a change in the strip position and/or skew of the strip at the mill. 8. The method as claimed in claim 1, wherein said first location is in advance of the steering device in relation to the snip feed direction and said second location is in advance of the reduction rolls. 9. The method as claimed in claim 1, wherein the steering device comprises a pair of pinch rolls extending laterally of the strip feed direction. 10. The method as claimed in claim 9, wherein the strip is passed between the pinch rolls and the steering device is operated by applying strip gripping forces to the pinch rolls at positions spaced apart along the pinch rolls and varying the relative strip gripping forces at those positions thereby to steer the strip. 11. An apparatus for rolling strip material, havinga pair of reduction rolls to receive the strip material;a roll thruster to apply squeezing forces to the reduction rolls at positions spaced apart along those rolls;a strip steering device to steer the strip to the reduction rolls and operable to vary the feed direction;a first strip position sensor to monitor the position of the strip at a first location in the vicinity of the strip steering device;a second strip position sensor to monitor the position of the strip at a second location in the vicinity of the reduction rolls; anda controller responsive to outputs of the first and second strip position sensors to operate the steering device to vary the direction of feed to the reduction rolls and also to vary the relative squeezing forces applied to the reduction rolls at the spaced apart positions. 12. The apparatus as claimed in claim 11, wherein the controller is operable to vary the relative squeezing forces applied to the reduction rolls at the spaced apart position so as to vary the position and skew of the strip entering the reduction rolls. 13. The apparatus as claimed in claim 11, wherein the controller operates the steering device in response to the instantaneous position of the strip at said first location. 14. The apparatus as claimed in claim 11, wherein the controller operates to vary the relative squeezing forces applied to the reduction rolls in response to the instantaneous positions of the strip at both said first and second locations. 15. The apparatus as claim 11, wherein the control means is effective to produce a strip steering device control signal by comparison of the position of the strip at said first location with a desired or set location. 16. The apparatus as claimed in claim 15, wherein the controller is operable to vary the relative squeezing forces applied to the reduction rolls by generating a further control signal dependent on the strip position at both said first and second locations when compared with desired or set positions for those locations. 17. The apparatus as claimed in claim 11, wherein said first location is in advance of the steering device in relation to the strip teed direction and said second location is in advance of the reduction rolls. 18. The apparatus claimed in claim 11, wherein the steering device comprises a pair of pinch rolls extending laterally of the strip feed direction. 19. The apparatus as claimed in claim 18, wherein the controller is effective to operate the steering device by application of strip gripping forces to the pinch rolls at positions spaced apart along the pinch rolls and variation of the relative strip gripping forces at those positions thereby to steer the strip.