Method of controlling continuous reheating furnace

A method of controlling a continuous reheating furnace, comprising the steps of sensing the flow rates, at a plurality of time points, of fuel and air introduced into each of a plurality of control zones into which a continuous heating furnace is divided;

• determining the temperature profile within the furnace up to the present time point by using means for determining a change in the temperature profile within the furnace with respect to time from the sensed flow rates of the thus-introduced fuel and air;
• finding the temperature of each slab introduced into the furnace at the present time point by using said temperature profile within the furnace determined at the present time point;
• predicting a future change in the temperature of the furnace on the basis of the thus-determined present temperatures of the slabs and the flow rate of said fuel introduced into each of said control zones, said flow rate set, according to said temperature change determining means;
• determining the predicted slab temperatures by using said predicted change of said furnace temperature;
• determining the flow rate of said fuel introduced into each of said control zones so as to render the differences between said predicted slab temperatures and the corresponding objective slab temperatures so as to be not greater than a predetermined value, and controlling the flow rate of said introduced fuel following an objective value based on the flow rate of said fuel so determined.