IMMERSION NOZZLE FOR CONTINUOUSLY CASTING BILLET AND METHOD FOR TAPPING MELT

摘要

PROBLEM TO BE SOLVED: To prevent seizure in a mole caused by melting of powder and bad slagging, to promote the float-up and the separation of non-metallic inclusion and bubble and to reduce porosity. SOLUTION: In an immersion nozzle used for continuous casting of a billet, two spouting holes 1a extending from the bottom surface of the immersion nozzle 1 to the side surfaces are arranged so as to face to each other. Each of the upper inner walls 1aa and the lower inner walls 1ab in these spouting holes 1a has a downward gradient with respect to the horizontal direction and the mean gradientθ(degree) is made to satisfy 20<=L.cosθ<=90 (mm) to the horizontal distance L (mm) between the outlet of the spouting hole 1a and the inner surface 2a of a mold 2 in the case of disposing the immersion nozzle 1 to the center of the mold 2.