Upper blowing lance for blowing converter and blowing method for converter

摘要

PROBLEM TO BE SOLVED: To provide an up-blowing lance 1 for converter blowing capable of reducing the generation of base metal loss not only by dust reduction but also by suppressing the generation of spitting in converter refining using an up-blowing lance 1 for converter blowing having a 4-hole nozzle 3 around a lance center axis 5.SOLUTION: In an up-blowing lance 1 for converter blowing, let intersection points of a lance tip plane 4 perpendicular to a lance center axis 5 with the lance center axis 5 and a nozzle center axis 6 be a lance center point 7 and a nozzle center point 8 respectively, in the lance tip plane 4, let a direction toward the nozzle center point 8 from the lance center point 7 be a radial direction 9, and let an angle between nozzles 3 adjacent each other around the lance center point 7 in the radial direction 9 be a spread angle β, as for tow spread angles β facing to the lance center point 7, the spread angle β is not less than 95° and not greater than 120°, thereby the generation of spitting is suppressed to reduce the generation of base metal loss.SELECTED DRAWING: Figure 1