Molten metal dosing furnace with metal treatment and level control and method

A dosing furnace for delivering molten metal to a downstream process, comprising:

• a holding chamber configured to contain a supply of the molten metal;
• a variable speed pump in fluid communication with the holding chamber, with the pump having a pump inlet connected to the holding chamber and having a pump outlet, and with the pump configured to pump the molten metal through the dosing furnace during operation;
• a degassing chamber in fluid communication with the pump through the pump outlet and including a degassing mechanism for removing gas and impurities from the molten metal flowing through the degassing chamber under the influence of the pump;
• a filter chamber located downstream and in fluid communication with the degassing chamber and including a molten metal filter for filtering the molten metal flowing through the filter chamber under the influence of the pump;
• a dosing chamber located downstream and in fluid communication with the filter chamber;
• and
• a molten metal level sensor located in the dosing chamber and connected to the pump for providing a pump speed control signal to the pump, with the level sensor configured to monitor the level of the molten metal in the dosing chamber and maintain a preset level of the molten metal in the dosing treatment chamber by controlling the speed of the pump with the pump speed control signal.

A method of controlling the level of molten metal in a molten metal dosing furnace, with the dosing furnace comprising:

• a holding chamber configured to contain a supply of the molten metal;
• a variable speed pump in fluid communication with the holding chamber, with the pump having a pump inlet connected to the holding chamber and having a pump outlet, and with the pump configured to pump the molten metal through the dosing furnace during operation;
• a molten metal treatment chamber in fluid communication with the pump through the pump outlet;
• a dosing chamber located downstream and in fluid communication with the molten metal treatment chamber;
• and
• a molten metal level sensor located in the dosing chamber and connected to the pump for providing a pump speed control signal to the pump,
• the method comprising the steps of:
• pumping the molten metal from the holding chamber to the molten metal treatment chamber;
• treating the molten metal in the molten metal treatment chamber;
• pumping the molten metal to the dosing chamber;
• monitoring the level of the molten metal in the dosing chamber with the level sensor;
• providing the pump speed control signal to the pump to control the speed of the pump and maintain a preset level of the molten metal in the dosing chamber;
• and
• dosing the molten metal from the dosing chamber to a downstream process.