NUMERICAL INVESTIGATION ON THE INFLUENCE OF THE SKID COOLANT TEMPERATURE ON THE REHEATING FURNACE PERFORMANCE

Steel making is one of the most energy intensive production process employed today. It involves different types of furnaces depending on the stage of the steel production process. Each of these furnaces operate at different temperatures that are used in the melting, reheating or annealing of the crude steel that is produced. This paper concerns the reheating process, where steel slabs are reheated for the subsequent hot rolling process. In this work a reheat furnace is studied using computational fluid dynamics with the objective of understanding the sensitivity of the skid coolant temperature on the performance of the reheat furnace. These skids transport the charge (slabs or billets) throughout the length of the furnace. Since these skids run through the entire length of the furnace, the influence of these is significant both for the furnace performance and product quality. The coolant temperature in these skids is varied and its influence on the furnace and charge quality is assessed. This is achieved by analysing the furnace temperatures and the heat fluxes both on the slab and at the skid slab contact points. This approach is experimentally validated and in this work, it is used to show the influence of skid coolant temperature on the temperature distribution inside the furnace and on the severity of the skid marks that arise due to the skid slab contact.