Development of Castables for Tundish with Enhanced Spalling Resistance

摘要

Wear mechanisms of the tundish castable lining were studied by analyzing used tundish linings, and the results of the study was used to improve the lining material. (1) Considering that the suppression of slag penetration was effective in suppressing spalling, we attempted to improve our castable by increasing the silica fine powder content. (2) Analysis of used linings confirmed that increased silica fine powder addition markedly helped suppress slag penetration as had been expected. We argued that the suppression of slag penetration was due to increase in the viscosity of the slag penetrating into pores, and therefore our reasoning and approach we had taken in our material development was correct. (3) Field tests confirmed less spalling and longer service lives of cast tundish linings that contained increased amounts of silica fine powder. They also confirmed a 35 percent reduction in the refractory cost index. This resulted not only from longer service lives but also from reduction in the repair amount because of less spalling while the tundish was in service.