HEATING METHOD OF STEEL SLAB BY HEATING FURNACE

PURPOSE:To easily and exactly apply slant heating to a steel slab by heating furnace, by specially varying heat sheltering efficiency due to a heat shelter plate above the steel slab, in heating the steel slab by the heating furnace prior to hot rolling. CONSTITUTION:The steel slab 3 charged from a charging port 1A of the continuous steel slab heating furnace 1 is heated to a prescribed temp. by plural burners 2 provided at both side walls of the furnace at intervals in the moving direction, then extracted to the outside of the furnace. Hereat, the heat shelter plate 4 made of refractory brick, heat resisting alloy, ceramic, etc., is provided above the slab 3 at a part in the furnace 1. For instance, the plate 4 is slanted as shown in the figure. As a result, difference is caused in heat sheltering effect due to the plate 4, the wider the interval between the plate 4 and the slab 3, the higher the heated temp. of the part, and slant heating of the slab 3 is extremely easily and exactly carried out. The plate 4 is attached between beams 6 fixed to lower ends of vertical arms 5 hung down from upper part of furnace body, and the arms 5 are freely raised and lowered by an elevator 7 provided above the furnace body.