Optimisation of edging amount for high accuracy plan view control in platemill

Algorithm to optimise the edging amount for high accuracy plan view control has been developed to improve plate yield. To produce rectangular shape of rolled plate, the edging amount that can minimise the crop length and widt h deviation must be determined from the operational analysis of plate mill. For the plan view control, new mathematical models to predict crop length at the top and bottom ends and width deviation at side ends are developed o n the basis of statistics and back propagation learning algorithm of neural network. Using new mathematical models, under given rolling conditions of broadside and finishing pass and the permissible tolerance in width deviati on, optimised algorithm which can achieve high accuracy plan view pattern i s proposed. The application of newly developed algorithm in actual plate mi ll for plan view pattern control reduced width deviation by 20%, and crop l ength by 30% on average with a suitable fishtail crop shape.