METHOD FOR HEATING STEEL SHEET COIL IN ROTARY HEAT-TREATING FURNACE

摘要

PURPOSE:To uniformly heat steel sheet coils by allowing exhaust gases injected form the burners provided on both side walls of an annular protective cover to collide with each other, and adjusting the position of the collision point in the widthwise direction of a furnace. CONSTITUTION:The steel sheet coils 2 are placed in one stage and two rows on the pedestal 6 of a hearth 4 traveling in the annular protective cover 5, an inner cover 1 is coated, and the steel sheet coils 2 are heated by direct flame burners 3 provided on both side walls of the annular protective cover 5. In this case, the burners 3 are opposed to each other so that the exhaust gases 7 injected from the burners 3 provided on both side walls are allowed to collide with each other. Consequently, the combustion exhaust gases 7 injected from the burners 3 collide with each other to form the secondary current 8, and the collision point of the exhaust gases an be appropriately adjusted by regulating the combustion load of the opposed burners 3. As a result, the temp. distribution in the widthwise direction of the furnace can be uniformized, and the steel sheet coils 2 can be uniformly heated.