Abstract: In the control of the tension of a workpiece which is rolled by a tandem rolling mill, a tension control method for a rolling mill wherein the tension of a workpiece is controlled by a looperless tension control method employing no looper at the threading stage of the top end and at the tail-out stage, and it is controlled by a tension control method employing a looper during the steady rolling.

Abstract: The rolling force, rolling torque, incoming workpiece thickness and roll gap at a first rolling stand are detected when a workpiece is fed into the nip between the rolls of the first rolling stand to provide their reference values P.sub.10, G.sub.10, H.sub.10 and S.sub.10 which are stored in a memory, and the reference torque arm l.sub.10 is computed on the basis of the reference values G.sub.10 and P.sub.10 of rolling torque and rolling force. The rolling force, rolling torque, incoming workpiece thickness and roll gap at a second rolling stand are detected when the workpiece is fed into the nip between the rolls of the second rolling stand to provide their reference values P.sub.20, G.sub.20, H.sub.20 and S.sub.20 which are stored in a memory, and the reference torque arm l.sub.20 for the second rolling stand is computed on the basis of the reference values G.sub.20 and P.sub.20 of rolling torque and rolling force. The torque arms l.sub.1 and l.sub.

Abstract: This invention relates generically to an automatic strip width control method in a hot rolling mill. More specifically, the present invention relates to a method for controlling a strip width to a predetermined width in a rolling mill equipped with edging rolls which seeks the deviation of strip width by estimating the temperature of a roll material under the edging rolls and controls the roll gap of the edging mill by means of the deviation of strip width thus estimated in order to control the width of the strip to a predetermined level on the basis of the technical conception that there is a certain relation between the temperature of the roll material and the deviation of strip width.

Abstract: Gage control apparatus and methods for tandem rolling mills are disclosed which are based on the low of constancy of mass flow. The apparatus and methods are attained by the discovery of the fact that the forward slip ratio of a mill stand varies as a linear function of the reduction ratio particularly when a plate material is rolled under relatively low tension. A ratio between thicknesses of the plate at the output and input sides of a particular stand of the tandem rolling mill and a ratio between circumferential speeds of rolls of the adjacent stands are used to calculate a thickness of the plate at the ouput or input side of each of the stands other than the particular stand. Each of the stands other than the particular stand is adjusted in its roll gap in accordance with a deviation of the calculated thickness from a desired thickness so as to cancel the deviation.

Abstract: A tension control system for use with a universal mill such as an H beam mill, in which a tension force in a billet, to be rolled, between roll stands is controlled so as to be maintained at zero. Providing that effective loads (Pu) are obtained by linearly summing horizontal and vertical rolling loads, the tension control system controls roll driving motors so as to maintain the respective ratios T/Pu of rolling torques T to effective loads (Pu) constant, thereby performing a non-tension control.

Abstract: In a tandem rolling mill consisting of at least a first rolling stand and a second rolling stand, the interstand tension is controlled by the steps of detecting the rolling force P.sub.10 and rolling torque G.sub.10 at the first rolling stand after a workpiece is fed into the nip between the rolls of the first rolling stand but before the workpiece is fed into the nip between the rolls of the second rolling stand, storing in a memory the ratio G.sub.10 /P.sub.10 representative of the reference torque arm value for the first rolling stand in a tension-free state, detecting the rolling forces P.sub.1B, P.sub.2B and rolling torques G.sub.1B, G.sub.2B at the respective rolling stands immediately after the workpiece is fed into the nip between the rolls of the second rolling stand, computing the reference torque arm value G.sub.20 /P.sub.20 for the second rolling stand in a tension-free state on the basis of these detected values, and controlling the rolling speed of the first or second rolling stand so that (G.