A system and method for filling a mold with molten aluminum includes a molten metal pump, a vessel configured to contain molten metal, a mold for receiving molten metal, and a conduit between the vessel and the mold. Molten metal is pumped in the vessel until it reaches a level at which it flows through the conduit and into the mold. The flow of molten metal into the mold is stabilized to maintain a level of molten metal in the mold. A skin of solid metal forms between the mold and the conduit, at which time the pumping of molten metal can cease. The mold with solid metal in it can be moved.

A smart molten metal pump system and method automatically controls the operating speed of the pump rather than requiring an operator to control the speed. The system includes a pump, a controller for controlling the speed of the pump, and one or more of a temperature sensor (such as a thermocouple), one or more of a device (such as a laser or float) to measure the depth of the molten metal, and one or more of a vibration sensor (such as an accelerometer) to measure vibration. The controller receives input about the temperature of the molten metal, and/or about the depth of the molten metal, and/or about the vibration of the pump or one or more pump components, and possibly other data. The controller analyzes the one or more inputs to vary the speed of the pump, turn the pump off, and/or send a communication to an operator.

A launder for use in moving molten metal includes at least one relatively narrow channel through which molten metal flows. Using a narrow, rather than broad, channel permits better control of the flow and helps prevent overflowing the launder or a structure adjacent the launder. A molten metal pumping or transfer system may utilize a launder as disclosed herein.

A system according to aspects of the invention includes a pump and a refractory casing that houses the pump or is in fluid communication with the pump. As the pump operates it moves molten metal upward through an uptake section of the casing until it reaches a rectangular outlet wherein it exits the vessel. The rectangular outlet is configured to be connected to, or may be attached to, a launder. Another system uses a wall to divide a cavity of the chamber into two portions. The wall has an opening and a pump pumps molten metal from a first portion into a second portion until the level in the second portion reaches an outlet and exits the vessel.

A scrap melting system and method includes a vessel that is configured to retain molten metal and a raised surface about the level of molten metal in the vessel. Solid metal is placed on the raised surface and molten metal from the vessel is moved upward from the vessel and across the raised surface to melt at least some of the solid metal. The molten metal is preferably raised from the vessel to the raised surface by a molten metal pumping device or system. The molten metal moves from the raised surface and into a vessel or launder.

A scrap melting system and method includes a vessel that is configured to retain molten metal and a raised surface about the level of molten metal in the vessel. Solid metal is placed on the raised surface and molten metal from the vessel is moved upward from the vessel and across the raised surface to melt at least some of the solid metal. The molten metal is preferably raised from the vessel to the raised surface by a molten metal pumping device or system. The molten metal moves from the raised surface and into a vessel or launder.

Embodiments of the invention are directed to a rotor for a molten metal pump and a molten metal pump including the rotor. The rotor has a main body and a top comprised of a material that is at least twice as hard as the main body. The top, among other things, may form a first portion of each rotor blade wherein the first portion directs molten metal into a pump chamber or other structure in which the rotor is mounted.

A furnace includes a tank having outer and inner walls defining a closed canal to be filled with molten metal continuously circulating along the canal. The canal includes at least one heating area having a heating component for transferring energy to the molten metal thus overheating it; at least one loading area for loading metal or metallic waste into the molten metal; a melting/treatment area for receiving the overheated molten metal and material dragged on its surface. The overheated molten metal transfers its exceeding energy to the material, causing its melting/treatment. The furnace has a central hollow delimited by the inner wall and a driving component within the hollow, having a rotor with at least one magnet body and coupled to a motor and configured to rotate upon activation of the motor, generating a magnetic field capable of causing circulation of the molten metal in a continuous and cyclical manner.

A bubble pump is provided. The bubble pump has an interior formed from a material that is resistant to attack by molten aluminum. The interior surface may be formed from a ceramic. The ceramic may be selected from the following: alumina, magnesia, silicate, silicon carbide, or graphite, and the mixtures thereof. The ceramic may be a carbon-free, 85% Al.sub.2O.sub.3 phosphate bonded castable refractory.

A device includes a molten metal pump and a metal-transfer conduit. A clamp may be used to attach the metal-transfer conduit to the pump. The pump has a pump base including an indentation configured to receive the metal-transfer conduit and align the pump outlet with the transfer inlet. The pump outlet may be formed in the indentation and preferably near the center of the indentation in order to better align with the transfer inlet. As the pump operates it moves molten metal through a pump outlet that is in communication with a transfer inlet in the metal-transfer conduit. The molten metal enters the transfer inlet, moves upwards in a passage in the metal-transfer conduit, and out of a transfer outlet.