The Design of In-Line Temperature Control Systems for Bar Mills

This study presents a workable, cost-effective proposal for eliminating the thermal distortions observed during production of rolled steel bars in billet mills. Manipulation of the temperature distributions in the workpiece to produce the desired shape of the final product was achieved through control of the heat supplied to a thermal housing designed for installation on the cooling bed to enhance homogenization of the heat flow across the dimensions of the product as it cools down from the final rolling temperature of about 900 C. The control system matches the changes in the operation of the rolls by introducing the concept of residence time the effect of which was the ultimate homogenization of the product temperature and elimination of the internal stresses.