Continuous Casting Tundish Weir and Porous Bottom for Inclusion Flotation

A gas-permeable plate is introduced as an intermediary component between the perforated weir and the molten steel. Inert gas bubbles rise through this plate, creating an upward flow that counteracts the downward short-circuit flow of inclusions while still allowing residual steel to be removed through the perforated weir. The gas bubbles act as a mediator that separates the harmful inclusion flow from the useful residual steel removal function.

Inert gas is blown through the gas-permeable plate to generate upward gas flow and bubbles in the molten steel. This pneumatic action creates a counter-current flow that opposes the downward short-circuit flow of inclusions, preventing them from reaching the perforated weir while still allowing residual steel to be effectively removed.

Gas blowing is localized to specific regions through strategically positioned gas inlet ports and gas-permeable plates rather than uniform distribution. The gas flow is concentrated in areas where inclusion flotation is most needed, while avoiding excessive surface agitation in regions where slag entrapment risk is high. This localized approach optimizes flotation efficiency while minimizing harmful surface fluctuations.

The gas flow rate, bubble size distribution, and gas injection timing are carefully controlled and optimized. By adjusting these parameters, the system achieves effective inclusion flotation while maintaining sufficient surface stability to prevent slag entrapment. The gas flow parameters are tuned to create gentle upward currents that carry inclusions to the surface without causing violent surface波动.