Abstract: In a paper making machine, a strip of paper is caused to pass around part of the periphery of a rotary device comprising a plurality of cylindrical bodies arranged side-by-side across the width of the strip and each body has means for producing a signal representing the tension in the portion of the strip which controls the body, the thickness of the portions is also measured. From this data, control signals are produced representing the stress per unit of cross-sectional area of the portions of the strip and the paper making machine is controlled to keep the control signals constant across the width of the strip.

Abstract: A rotary cutter for sheet or strip material, comprises a roller with an air-pervious surface to which negative air pressure can be applied and an axially disposed knife in the roller which intermittently projects radially from the roller to cut the material when held thereon by negative pressure. Such a cutter can conveniently form part of a belt wrapper for starting a coil of material, where unwanted material can be cut and discarded.

Abstract: To operate a rolling mill to roll metal strip with a satisfactory degree of flatness, signals from tension detecting means located downstream of the mill rolls are used continuously to determine the best symmetrical parabola which fits the shape of the strip and a parameter of the parabola is used to bring about an adjustment of the bending of the mill rolls in such a sense as to change the parameter substantially to zero. Signals from the detecting means may be used in addition to control the steer of the mill and adjust the temperature of the roll assemblies along their length.

Abstract: For detecting the temperature profile of a moving strip, strip is caused to pass in contact with a series of hollow rotors which are spaced across the strip width, and each of which is supported by a gas bearing. A thermal detector is located within each rotor to respond to the temperature of that part of the strip in contact with the rotor.The rotors may also be used to detect the variation in tension across the strip width. In that case, the thermal detectors can modify the tension measurements to compensate for thermal errors.