| 摘要 |
PURPOSE:To prevent the cooling of molten metal in the inside and to prevent the thermal damaging of a top cover by mounting a middle cover of high fire resistance, corrosion resistance and heat resistance to a tundish. CONSTITUTION:A middle cover constituted of plural divided bodies consisting of bottom plates 22, side walls 23, and partition walls 26 and provided with cylinders 24, 25 corresponding to the molten metal charging port 14 and preheating flame blow port 15 of a top cover 11 of a tundish 1 is mounted to the lower part of said top cover 11. The middle cover is made of the plastic material prep. by compounding aluminum silicate, asbestos, rock wool, other inorg. fibrous materials, binders or a small amt. of org. fibrous materials with refractory aggregate of silica base, silica base and silicon carbide, magnesia base, etc. Heat insulating materials such as expanded vermiculite, expanded pearlite, smoked chaff or other grains are packed in the hollow spaces 27 enclosed by the plates 22, the walls 23, the walls 26 and the bodies 24, 25. The heat insulating effect of the molten metal in the tundish is improved, and the inside surface of the top cover is kept free from receiving thermal damages by the molten metal. |
