炉外铝热法生产金属铬的冶炼炉筒,一般都采用直井式园形铸铁筒。冶炼的金属锭在一吨以下时,可使用上口小,下口大的整体铸铁筒;冶炼的金属锭在一吨以上时,炉筒须由两半或四半所组成,即所谓可拆卸式的炉筒;下口置于衬有镁砖的镁砂盘上,炉筒的下部容纳金属部位衬以镁砖;炉筒的连接用螺栓紧固,缝隙用石棉耐火泥填塞。这种铸铁炉筒的最大缺陷是炉简直接受热,极易变形,使用寿命较短,一般只能使用30— Alumina furnace outside the production of metal chromium smelting furnace tube, generally used straight shaft type cast iron tube. When smelting metal ingot is less than one tonne, the whole cast iron tube with small upper mouth and large mouth can be used; when the smelting metal ingot is more than one ton, the furnace tube shall be composed of two halves or four halves, so-called detachable The lower mouth is placed on a magnesia plate lined with magnesia brick, the lower part of the hearth is lined with magnesia brick; the connection of the hearth is bolted and the gap is filled with asbestos refractory mud. The biggest drawback of this cast iron furnace tube stove simply heat, easily deformed, short life, the general can only use 30-