Research on roll contour and control strategy for edge drop control of high-strength steel in the cold rolling precision mill

In cold rolling of high-strength steels using precision multi-roll mills, significant edge drop issues compromise product quality and adversely affect subsequent processing stages. To enhance the edge drop control capabilities of an S6-High cold rolling mill, this study designs a roll contour for the working and side support rolls and develops an accompanying position control strategy. Initially, a reciprocating multi-pass rolling simulation finite element model is constructed using ABAQUS software, and its accuracy is validated by comparing actual and simulated section profiles. Based on the ridge regression algorithm, the evolution of section profiles under different roll contours calculated by the model is fitted. In conjunction with the differential evolution algorithm, the optimisation of roll contour parameters aims to improve roll adaptability and edge drop control. Specifically for the S6-High cold rolling mill, the transverse bending coefficient and horizontal stiffness of the working rolls are defined, and a side support roll position control strategy is developed, integrated with the side support roll variable crown length (VCL) roll contour to enhance edge drop control capabilities. Field applications demonstrate that the methodologies developed in this paper effectively reduce the average edge drop of cold-rolled high-strength steel by 56.82%, significantly enhancing the sectional profile quality during the precision rolling of high-strength steels.