Prevention against clogging of nozzles during continuous casting of steel by modification of non-metallic inclusions with calcium

摘要

The reasons for clogging of nozzles on industrial steel heats in Huta Katowice were identified. The results of identification of deposits from tundish nozzles were presented. It was found that clogging of nozzles was mainly caused by form mg of CaS inclusion, as a result of too large additives of calcium at too high content of sulphur in steel and secondary bath oxidation (on the way between LHF and tundish) resulting in forming of Al_2O_3 inclusions and not completely modified calcium alum mates with high melting temperature that sedimented atnozzles when casting.