NEW BOTTOM-INJECTION TUYERES IN LADLES

摘要

PDF tuyeres made at the Magnezit Joint Stock Company are used for inert-gas injection in steel-casting ladles at the Chelyabinsk Metallurgical Works. They last 2-3 melts; around 30 percent of the tuyeres are not used with the first melt. Given the poor quality of Russian tuyeres and the high cost of imported tuyeres, Mechel Joint Stock Company has undertaken research to create new tuyeres. Since 1997, tuyeres with porous structure, in which the porosity is created by materials of the fraction 0.5-2.0 mm have been replaced by tuyeres with directed porosity; manufacture by pressing and vibrational tamping has been replaced by vibrational compaction; and masses based on phosphate binders have been replaced by low-cement thixotropic refractory concretes.