Mathematical Modelling of Roll Cooling and Roll Surface Stress

In a hot strip mill, the quality of the rolled products and the productivity of the mill depend on the efficiency of roll cooling to a great extent. To study the influence of the cooling system on roll performance, a good understanding of the thermal aspects of roll cooling is essential. Mathematical models to predict temperature development in the work roll and compute thermal strain induced at the roll surface during rolling were developed and applied to the upper work roll of the 1st stand of the finishing mill of HSM at Tata Steel. The models were used to predict temperatures and thermal stresses/strains in the roll under various cooling conditions, thus examining the efficiency of the existing roll cooling system and exploring the scope of optimizing it.