| 摘要 |
PURPOSE:To perform the efficient unoxidizing heat-treatment of a steel strip, in direct flame-type unoxidizing heat-treatment in an apparatus for continuously annealing the steel strip or the like, by making a nozzle for gas fuel movable in a radiant burner and setting the injection angle of air at a specified value. CONSTITUTION:When a steel strip is heated under an unoxidized condition in a continuous annealing oven, a continuous hot-dip zinc-coating apparatus or the like for the steel strip, it is heated by a radiant burner. At the side wall 11a of a burner tile forming the combustion chamber C for a cylindrical burner 11, a plurality of openings 13 for ejecting air A are provided with an angle theta of 60 deg. at most to he connection of the side wall 11a of the tile. Burner nozzles 12 provided with a plurality of openings 14 for ejecting gas fuel F are slidable provided along the axial line, and their top ends are set close to the rear wall 11b of the titled. Combustion is performed by controlling the flow ratio of the air A to the fuel F above 1.5 and the ratio of air below 1.0, to heat the entire inner surface of the combustion chamber C. Consequently, the steel strip is heated under an unoxidized condition with excellent thermal efficiency without the need to previously mix air and fuel. |
