Abstract: There is provided hydraulically-operated work roll gap control cylinders forming a closed-circuit hydraulic system during rolling, and there are also provided hydraulically-operated backup roll control cylinders to which is connected a rolled product thickness gauge in order to keep constant the work roll gap depending on the pressure existing in the closed-circuit hydraulic system. The apparatus is provided with a hydraulic volume compensator operating in conjunction with the closed-circuit hydraulic system of work roll gap control and is also provided with a logic module connected to said compensator. The volume of fluid contained in the closed-circuit system changes in response to the corrective signal characteristic of a deviation of the strip thickness from the specified gauge. The passage of the signal to the hydraulic volume compensator is cleared or blocked by a special transportation lag unit.

Abstract: Disclosure is made of a position sensor comprising a plurality of inductance coils with open magnetic circuits. One of the coils has two pairs of poles. The position sensor further includes a shunting element designed for movement along the axis of the coils and connected to a moving body whose position is to be found. The shunting element has groups of holes arranged along its axis. In each group, the holes are arranged along the perimeter of the shunting element. The interpole distance of the coil with the two pairs of poles is specially selected with due regard for the diameter of the holes and the interhole spacing to ensure a high accuracy of the measurements.