Investigations into the influence of asymmetric factors and rolling parameters on strip curvature during hot rolling

Finite element (FE) techniques have been used to analyse the effect of asymmetrical factors and rolling parameters on the direction and severity of strip curvature. A plane strain FE model has been constructed to simulate the rolling of low carbon steel strip at high temperatures. The asymmetric factors considered were workpiece temperature differentials, roll speed mismatch and differential interface friction conditions. The rolling parameters include initial strip height, reduction, average roll speed, average workpiece temperature and average coefficient of friction. In addition to the FE model predictions, trials have been carried out on the reversing rougher of Corus, Port Talbot hot mill. Trials were conducted to investigate the effectiveness of roll speed mismatch as a means of controlling strip curvature.