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.

A molten metal processing apparatus selected from a pump, a degasser, a flux injector, and a scrap submergence device constructed to include at least one element comprised of C/C composite.

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 molten metal pump assembly and method to fill complex molds with molten metal, such as aluminum. The pump assembly includes an elongated shaft connecting a motor to an impeller. The impeller is housed within a chamber of a base member such that rotation of the impeller draws molten metal into the chamber at an inlet and forces molten aluminum through an outlet. A first bearing is adapted to support the rotation of the impeller at a first radial edge and a second bearing adapted to support the rotation of the impeller at a second radial edge. A bypass gap is interposed between the second bearing and the second radial edge. Molten metal leaks through the bypass gap at a predetermined rate to manipulate a flow rate and a head pressure of the molten metal such that precise control of the flow rate is achieved.

A vertical member, which is preferably a support post used in a molten metal pump, includes a ceramic tube and tensioning structures to add a compressive load to the tube along its longitudinal axis. This makes the tube less prone to breakage. A device, such as a pump, used in a molten metal bath includes one or more of such vertical members.

A vertical member, which is preferably a support post used in a molten metal pump, includes a ceramic tube and tensioning structures to add a compressive load to the tube along its longitudinal axis. This makes the tube less prone to breakage. A device, such as a pump, used in a molten metal bath includes one or more of such vertical members.