METHOD FOR CONTROLLING TENSION IN CONTINUOUS ROLLING MILL

摘要

PURPOSE:To easily control the tension between several stands on the down stream by calculating the torque arm of each stand from each rolling torque and rolling load stored in the passing-through stage of a tail end and using the same to calculate the tension of a steel product of the next pass. CONSTITUTION:The speeds of stands #3-#1 are locked and after a specified period, the rolling torque G and rolling load P of the stands #3-#1 are stored when the rear end of the steel product passes through the stand #4. The time until the rear end passes through the stand #3 after passing through the stand #4 is measured. The previous stand speeds are unlocked when the time is above the specified value. The tension between the stands #2 and #1 is then calculated in accordance with the torque arm and the speeds of the stands #2, #1 are corrected by which the tensionless control is executed. The torque G and the load P when the rear end passes through the stands #4-#2 are thus stored. The respective torque arms are determine by the prescribed equation from the torque G and load P stored when the rear end passes through the stands #4-#2 after the steel product passes through the entire stand. The tension of the next rolling is calculated therefrom and the tension is so controlled as to attain the target value.