Edge drop and high spot control of hot-rolled non-oriented electrical steel strip by taper roll shifting strategy

Abstract

A hot rolling schedule of non-oriented electrical steel of the same strip width suffers from severe uneven roll wear, which leads to high spots and excessive edge drop. To eliminate these shape defects, a ‘keep-smooth’ shifting strategy of the taper roll was proposed: the strategy aimed at a smooth roll wear contour and was achieved by a varying-rate shifting mode. A roll wear model was developed to predict the evolution of the wear contour under different shifting parameters, and the optimal parameters were obtained by the adaptive particle swarm optimisation algorithm. The effect of the new shifting strategy on the strip profile was studied based on a 3D finite element rolling model. The industrial application verified the new taper roll shifting strategy, as both the edge drop and high spots were alleviated and the rolling length of a schedule was extended by about 10 km.