Improving Melting Efficiency through the Application of New Refractory Materials

Ladle design and ladle practices have a significant effect on a foundry operation and product quality. Large steel temperature losses or instabilities in the pouring temperature are frequently compensated by tapping at higher temperatures dramatically increasing furnace and ladle lining wear, oxidation of the steel, alloying element losses, and energy consumption in steel melting. Ladle lining materials need to satisfy a complex array of often conflicting requirements. For example, ceramic materials for linings must possess a high strength at liquid steel temperatures to prevent erosion and crack formation. However, linings need to also have a low thermal conductivity which typically increases as the strength improves. Temperature problems became more severe with decreasing ladle size. This paper summarizes test work of new lining materials in a 100 lb liquid metal capacity ladle in the UMR foundry designed with a temperature measurement system installed in the lining. Several different working linings materials were tested under similar conditions. Results from these foundry experiments were compared with thermal conductivity measurements in the laboratory and computation fluid dynamic modeling results. From this work, UMR\u27s newly developed porous alumina linings were shown to have properties that could result in significantly lowering energy requirements in steel foundries