| 摘要 |
<p>The present invention discloses an alkali oxide free low density refractory material especially adapted for use as a disposable liner material for molten metal containing vessels. This material includes about 0.1 to about 2 weight percent of a stiffening agent, about 0.1 to about 2 weight percent of a set retarding agent, about 0.1 to 6 weight percent of density reducing materials, about 0.1 to about 5 weight percent of a plasticizer, up to about 2 weight percent of a secondary binder, and the balance of a refractory aggregate which is preferably MgO. The stiffening agent and set retarding agent are used in substantially the same amounts to provide the disclosed refractory material with increased resistance to slumping while, at the same time, allowing spraying apparatus residence times of up to 30-40 minutes without clogging. The composition includes less than about 0.1 weight percent of alkali oxides, so that reaction and fusion of the disposable liner with a permanent liner is avoided thereby allowing increased ease in mechanical removal of the disposable liner. Also, the invention relates to methods for applying the disposable lining by spraying and an apparatus for holding molten metal which includes a steel shell, a relatively permanent refractory lining disposed therein and a disposable lining disposed upon at least a portion of the permanent refractory lining.</p> |
