Taking standard, high-alumina nozzles of steel-making ladles with a typicall life of up to 10-24 heating cycles as an example, microstructural changes are presented. These were observed when comparing before and after-operation conditions of the nozzle refractory material, in the latter case with and without fire-piercing the nozzle bore with an oxygen lance. In order to design new process technology concepts, the cause of nozzle wear were determined and the mechanism of clogging the nozzle bore with deposits was elucidated. The practical outcome of the study are new high-alumina bodies which allow increasing the service life of nozzles up to 25-40 heating cycles and to alleviate the problem of nozzle clogging which was confirmed by, among others, microstructural examinations.
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