Measurement and Prediction of Lubricatio

In conventional continuous casting of steel, lubricating the mold with either mold powder or oil is crucial for preventing the solidifying steel shell from sticking. This paper discusses the role of mold powder in forming a molten slag layer that protects the molten steel from oxidation, regulates heat transfer, absorbs inclusions, and minimizes surface defects. The interfacial layer created by the slag significantly influences both lubrication and heat transfer, with a thicker layer facilitating better lubrication and reducing friction. However, challenges arise with increasing casting speeds, as lower slag consumption leads to a thinner molten layer, resulting in potential defects and breakouts. A methodology involving the measurement of mold powder consumption over time provides insights into lubrication performance. Notably, the study emphasizes that normalized consumption per unit area of strand serves as an effective measure of lubrication. Understanding the dynamics of liquid layer thickness and velocity gradients across the liquid flux layer is crucial for optimizing casting operations, ultimately aiming for a stable continuous casting process with minimal defects. The findings underscore the importance of adequate slag infiltration in maintaining the required lubrication and heat management during high-speed casting operations.