Study of the deskulling problem of tundishes in continuous casting

This paper reports an investigation carried out on the deskulling problem of tundishes at the Mobarakeh Steel Plant in Iran. Bad deskulling of tundishes is a major problem in continuous casting of steel, and can occur due to the chemical reactions between the refractory lining and the slag carry over from ladle to tundish. Post-mortem analysis of the slag/commercial magnesia-olivine mix refractory interface by XRF, XRD, OM, TEM, SEM and EDS techniques showed that the volume of slag carry over from ladle to tundish has a direct effect on refractory wear in the tundish. The percentage of tundishes where the skull was locked into the safety lining was dependent on the slag basicity and amount of Al2O3 in the slag inside the tundish. It has been shown that a direct corrosion mechanism occurs in basic slag and also in acidic slag containing low alumina, but an indirect corrosion mechanism occurs in acidic slag containing high alumina.