GB1098649A - Workpiece tension and shape control method and apparatus - Google Patents

Abstract

1,098,649. Rolling. WESTINGHOUSE ELECTRIC CORPORATION. Dec. 22, 1964 [Jan. 9, 1964], No. 52030/64. Heading B3M. [Also in Division G3] In a system for automatically controlling the thickness of rolled material at points across its width, a plurality of tension detectors arranged across the width control a plurality of tension adjusters which are also arranged across the width and are each responsive to signals from more than one detector. In one arrangement described, tension in rolled material is detected by five rollers pressing on the material across its width. Signals from, for example, strain gauges associated with these detectors are separately compared with signals representing desired tension and any errors, which may be in digital form, are applied to integrators. The output of each integrator, besides being applied to an indicator, periodically controls, through a limiter, an electric screwdown motor or hydraulic actuator applying force to the rolls at a position corresponding to that of the detector involved. In addition, a proportion of the signal applied to each screwdown device is also applied to adjacent sorewdown devices in such sense as to cancel the effect of the adjustment of the first mentioned screwdown device in adjacent zones. The average of all the error signals is also applied to adjust the speed of the motor driving the rolls in a sense tending to correct the tensions. The overall effect of the controls is to produce a flat sheet of uniform thickness. The error signals are also arranged to control the forces applied at the next roll stand in a multi-stand rolling mill. In another arrangement the signals from different pairs of tension detectors are compared and any differences control the forces and torques applied at appropriate points on the rolls to obtain constant tension across the width of the material. A single tension detector moved in succession to a number of positions across the material may be used instead of a plurality of detectors.