METHOD FOR CONTROLLING SPEED OF TANDEM MILL

PURPOSE:To hold speed equalizing property of each stand even when a high response stand and low response stands coexist. CONSTITUTION:This method is for controlling speed of a tandem mill in which the rolling stands (1STD, 3-6 STD) whose speed control systems have low speed responsiveness and the rolling stand 2STD having high responsiveness coexist by providing the speed control systems for controlling motors 18 with which the rolls of rolling stands are driven on every rolling stands (1 STD-6STD). The actual speed of the low response stand 3STD is estimated/calculated with a speed simulator 30 from speed command values D3 outputted from a multiplier 16B, actual speed correcting value Vc is calculated by correcting the drooping characteristic of the same stand to the actual speed and the speed command value D2 of the high response stand 2STD is calculated by multiplying the ratio R (2/3) of the set speed of the high response stand to the set speed of the low response stand to the Vc with the multiplier 16A.