SECONDARY COOLING METHOD AND COOLING NOZZLE FOR CONTINUOUSLY CAST SLAB

摘要

PURPOSE:To provide an effective secondary cooling method and cooling nozzle, by which uniform cooling to a cast slab can be executed at the secondary cooling zone and the cast slab having no surface defect, etc., is continuously cast. CONSTITUTION:Tip part of the spray type nozzle 3 for secondary cooling set at between guide rolls 2 below a continuous casting mold 1, has structure, which forms curved surface or polyhedron and sets discharging holes 4 having =40 deg. in drawing direction and =120 deg. in width direction of the cast slab to widening angles for cooling spray at =3 lines in the drawing direction and =2 lines in the width direction of cast slab, and the secondary cooling is executed to the continuously cast slab. By this method, the cast slab having no surface defect, etc., can be stably produced.