METHOD FOR CONTROLLING COMBUSTION IN MULTIZONE CONTINUOUS HEATING FURNACE

摘要

PURPOSE:To hea billets to be rolled to a target rolling temp. with high thermal efficiency and to extract the same from a multizone continuous heating furnace in the stage of heating said billets in said furnace by adopting a combustion control system which adds a specific improvement to a standard heat pattern system. CONSTITUTION:The present temp. is determined from the past heating process for all the billets in a multizone type heating furnace such as a four-zone type continuous heating furnace consisting of the 1st-4th zones in the stage of heating the billets to be hot rolled to a target temp. in said heating furnace. The future combustion control to heat the billets to the heat pattern for each billet as a target is predicted on assumption that the extraction of the billets from the inside of the furnace is accomplished in accordance with the extraction schedule for the present billets from the heating furnace at the same instant as above. The degree of extraction soaking of all the billets in all the combustion zones and the future change in the furnace temp. and fuel flow rate in each zone with time are predicted and whether the values are above or below the target value at the extraction is evaluated in accordance with the prediction. The heat patterns are corrected in accordance with the result of said evaluation and the heating is controlled.