METHOD FOR ELECTROMAGNETIC STIRRING IN CASTING MOLD OF CONTINUOUS CASTING MACHINE FOR SLAB

摘要

PURPOSE:To prevent the crack and breakout of an ingot and to improve the effect of degassing and removing inclusions and the quality of the ingot by stirring the molten metal in a casting mold while changing the stirring directions to two upper and lower stages. CONSTITUTION:An outside wall 2 encloses the outside periphery of mold copper plates 1 enclosing the mold cavity around an ingot axis 9. A cooling chamber 8 is formed of such outside wall 2. Electromagnetic stirring coils 3, 4 are disposed in two upper and lower stages so as to enclose the cooling chamber 8. The molten metal in the upper part of the mold is continuously and vertically subjected to swirling stirring 6 in the direction perpendicular to the axis 9. On the other hand, the molten metal in the lower part of the mold is continuously and laterally subjected to the swirling stirring in the direction parallel with the axis 9. The degassing effect is improved and the floating of the inclusions is accelerated by the parallel stirring flow in the lower region of the casting mold in the above-mentioned manner. The contact surface of the powder and the molten metal in the casting mold is renewed and the absorption of the floating inclusions is accelerated by the vertical stirring flow in the upper part of the mold. The ingot defects are thereby decreased.