Lance for treating crude iron or steel

摘要

The lance consists of a lance pipe which is provided with an inner pipe and is surrounded by a refractory sheath. In addition, the lance pipe is surrounded at a distance by an interposed pipe fixed thereto, the annular gap thus formed being filled with a refractory inner lining. The anchorage holding the refractory sheath in position is fitted to the outer surface of the interposed pipe.