| 摘要 |
PURPOSE:To obtain a submerged nozzle having excellent thermal shock resis tance, corrosion resistance and mechanical strength by kneading mixed powders composing of powders of refractory, graphite and sulfur by a binder to form and burn at the time of producing the submerged nozzle for continuous casting of molten steel fitting to a ladle, tundish etc. CONSTITUTION:At the time of producing the submerged nozzle fitted to the ladle and tundish for the molten steel in the continuous casting apparatus for the molten metal, 10-50 pts. wt. of the binders of phenol resin, tar, pitch, etc., are added to 100 pts. wt. of granules having <=3 mm grain size of refractories, such as alumina, mullite, chamotte, zirconia, magnesia, silicon nitride, silicon carbide, etc., 30-100 pts. wt. of carbonic powders having <=1 mm grain size, such as natural graphite, artificial graphite, coke, etc., and 0.01-2 pts. wt. of fine powders of sulfur having >=99% purity and <=5 mum grain size to knead. Then, after forming it to the nozzle-shape under pressurizing, it is burnt at 900-1500 deg.C under reducing atmosphere, to obtain the submerged nozzle without developing any crack caused by the thermal shock, etc. |
