| 摘要 |
1. A casting nozzle for molten material and more particularly suitable for liquid steel, characterized in that it comprises at least one part of unburned uncompressed concrete consisting of (1) a granulate or aggregate of particules containing more than 99% by weight of alumina which has previously undergone heat treatment up to the temperature of fusion or fritting and (2) a binder consisting of from about 75 to 85% by weight of alumina, the rest of the binder substantially consisting of calcium oxide, this binder having previously undergone heat treatment up to the temperature of fusion, said part being covered with a layer of degradable refractory concrete which is likely to undergo gradual erosion due to contact with the molten materials as they are cast.
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