| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a cast slab of high quality reduced in foaming defects, flux defects, etc. <P>SOLUTION: This method for continuously casting steel uses a continuous casting machine including a pair of upper magnetic poles and a pair of lower magnetic poles facing each other with a mold long side part held in between, and a submerged nozzle whose downward molten steel discharge angle from a horizontal direction of a molten steel discharge hole is at least 30° and less than 50°, to continuously cast steel while braking the flow of molten steel by a direct current magnetic field applied to each of the upper magnetic poles and lower magnetic poles. In the method, the opening area of each molten steel discharge hole of the submerged nozzle is set to 3,600-8,100 mm<SP POS="POST">2</SP>, the casting speed is set to at least 1.0 m/min, and the intensity of the direct current magnetic field applied to each of the upper magnetic poles and lower magnetic poles, and the intensity ratio of both direct current magnetic fields are optimized according to the width of the slab to be casted and the casting speed to obtain the cast slab of high quality reduced in defects caused by micro bubbles and mold flux as well as defects caused by a nonmetallic inclusion and mold flux which are conventional problems. <P>COPYRIGHT: (C)2013,JPO&INPIT |
