METHOD FOR FIXING STEEL TUBE IN WHICH MOLTEN STEEL CLEANLINESS OF BOTTOM PART OF CAST SLAB IS IMPROVED IN REUSE IN HOT CONDITION

摘要

PROBLEM TO BE SOLVED: To improve the yield of a cast slab by enhancing cleanliness of a bottom part of the cast slab.;SOLUTION: When a tundish 1 is reused in a hot condition, sand 6 is sprayed on the outer circumferential side of a steel tube 5. Thus, melted portions m₁, m₃ of a refractory 11 are embedded with the sand 6, and the steel tube 5 is fixed to the bottom part of the tundish 1. Thus, the casting width W of the sand 6 is set to be larger than the maximum melting width w₁ of the refractory 11 by ≥10[mm]. Further, the height H of the sand 6 after it is charged is set to be ≥10[mm] and ≤30[mm]. The composition of the sand is set so that the content of Cr₂O₃ is ≥60 [mass%], the content of SiO is ≥20 [mass%], and the total content of Fe₂O₃, Al₂O₃, and Na₂O is ≤10 [mass%].;COPYRIGHT: (C)2013,JPO&INPIT