Synthetic setting technology of roll-bending force of five-frame four-roll cold continuous rolling device

The invention relates to a roller bending force comprehensive setting method for a five-stand four-roller cold tandem rolling mill, and belongs to the technical field of strip cold rolling. The method can improve plate shape quality of finished products and prolong the service life of a roller bending cylinder. The method is characterized by comprising the following operation steps: (a) acquiring parameters of equipment of the mill; (b) acquiring key technological parameters; (c) setting a roller bending force initial setting value X0={Swi0 i=1, 2, 3, 4 and 5}, an iteration precision epsilon, an allowable maximum roller bending force allowance difference eta 1, and the minimum roller bending allowance eta 2; (d) calculating roller bending allowance of (No.1 to No.5) stands Swi; (e) judging whether inequations that max(absolute [Swi-Swj ] i=1, 2, 3, 4 and 5; j=1, 2, 3, 4 and 5) is less than or equal to eta 1 and min(Swi i=1, 2, 3, 4 and 5) is more than or equal to eta 2 come into existence at the same time, if so, entering (f), otherwise, entering (c), and setting the initial value until the inequations are met; (f) calculating a front pull transverse distribution value of the No.5 stand sigma 15j; (g) calculating a plate shape control objective function F(x)=(max(sigma15j)-min(sigma15j)/T15; and (h) judging whether Powell conditions come into existence, otherwise, changing the setting value and repeating the steps from (c) to (g) until the Powell conditions come into existence, and obtaining the optimal roller bending comprehensive setting value.