Abstract: A method and apparatus for treating molten metal in a bottom pour vessel through a pouring opening controlled by a slidable gate closure member. A dual concentric tuyere having a central conduit and an outer annular conduit is positioned in the pouring opening of the vessel. Treating material is injected into the molten metal through the central conduit of the tuyere and a coolant is passed through the outer annular conduit of the tuyere. After completion of the treatment, oxygen is blown through both the central conduit and the annular conduit to burn back the tuyere, opening the nozzle well for pouring.

Abstract: A method and apparatus for treating molten metal in a bottom pour vessel through a pouring opening controlled by a slidable gate closure member. A dual concentric tuyere having a central conduit and an outer annular conduit is positioned in the pouring opening of the vessel. Treating material is injected into the molten metal through the central conduit of the tuyere and a coolant is passed through the outer annular conduit of the tuyere. After completion of the treatment, oxygen is blown through both the central conduit and the annular conduit to burn back the tuyere, opening the nozzle well for pouring.

Abstract: A process for protecting oxygen injection nozzles and the surrounding refractory lining of a molten metal refining vessel having such oxygen injection nozzles beneath the bath surface. The injection nozzle comprises at least three concentric pipes, the central conduit thereof being connected to a source of oxygen, the outer annular conduits thereof each being supplied with a protective fluid, said protective fluid containing at least one hydroxyl compound or water or a mixture thereof. The protective hydroxyl compounds are selected from the gaseous or liquid alcohol group and preferably from the aliphatic alcohol group. Methanol, ethanol, propanol and butanol are preferred alcohols.Apparatus for carrying out the process is also disclosed.

Abstract: Oxygen is blown into an open hearth furnace beneath the surface of the molten metal through a jacketed tuyere, each tuyere angled toward the center of the furnace. A high volume of jacketing coolant is injected through two separate annular passageways around the oxygen to form a large skull around the tuyere. Apparatus is also disclosed for carrying out the process.

Abstract: Oxygen is blown into an open hearth furnace beneath the surface of the molten metal through a jacketed tuyere, each tuyere angled toward the center of the furnace. A high volume of jacketing coolant is injected through two separate annular passageways around the oxygen to form a large skull around the tuyere. Apparatus is also disclosed for carrying out the process.

Abstract: A method for controlling the casting rate in the continuous casting of liquid metals by monitoring the casting temperature downstream from the continuous casting mold and opening or closing the bottom-pour nozzles on the hot metal vessels when the casting temperature at such point deviates from a preselected temperature range. The method includes switching of the control strand in multiple strand casters whenever the control strand has some difficulty.