| 摘要 |
<p>A shroud apparatus for the continuous casting of steel comprising a fused silica or like refractory oxide nozzle having the outer surface thereof which is normally contacted by the layer of fused slag on the surface of the molten metal in the continuous casting mold when the nozzle is in normal operating position enclosed by a ring or sleeve formed of a slag resistant material, such as silicon nitride, boron nitride or zirconium diboride. In one embodiment the nozzle has a ring member slidable axially along the length thereof with the ring floating in the molten metal and having one end immersed in the molten metal and the other end extending above the slag layer. In another embodiment the nozzle has a protective ring member formed of the slag-resistant material mounted fixedly on the outer surface of the nozzle with the ring being of such length and positioned axially on the nozzle so that only the protective ring will be contacted by the slag layer during the continuous casting operation. The method of continuous casting using such a shroud apparatus greatly increases the continuity and efficacy of the continuous casting operation and improves the quality of the continuous casting.</p> |
