Disclosed are components covered with a protective coating for use in a molten metal bath (or comparable environment) and devices including such components. The protective coating is preferably a ceramic sleeve adhered to a non-coated component by cement. A component with the protective coating is more resistant to degradation in molten metal than is the component without the coating, and may be manufactured by the process of (a) placing the protective coating over the non-coated component, and (b) injecting cement into the space between the non-coated component and protective coating, wherein at least some of the cement is injected through a passage in either the non-coated component or the protective coating.

Protective coatings for molten metal devices

Improved components for a molten metal pump include a coupling for connecting a rotor shaft to a motor shaft, a rotor shaft and a rotor. The rotor shaft has a first end and a second end wherein the first end optionally has a vertical keyway formed in the outer surface of the shaft. The second end optionally has flat, shallow threads. The coupling can be one-piece or multi-piece, includes a cavity for receiving the first end of the rotor shaft and, if the first end of the rotor shaft has a keyway, the coupling includes a projection in the cavity for being received at least partially in the keyway. The rotor includes a connective portion that connects to the second end of the rotor shaft. If the second end of the rotor shaft includes flat, shallow threads, the connective portion is essentially a bore having flat, shallow threads configured to receive the second end of the rotor shaft. Optionally, the first end of the rotor shaft may have flat, shallow threads in which case the coupling would have a cavity that receives the first end of the rotor shaft, wherein the cavity has flat, shallow threads.

Molten metal pump components

A device for releasing gas into molten metal includes a base having a discharge. The discharge has a first section including a first cross-sectional area and a second section including a second cross-sectional area, wherein the first section is upstream of the second section and the first cross-sectional area is smaller than the second cross-sectional area. A gas-release opening is positioned so that it can release gas into one or more of the first section or the second section. As the molten metal moves from the first cross-sectional area to the second cross-sectional area gas is released into the molten metal and the molten metal flow helps to draw the gas into the flow, thereby lowering the pressure required to release gas into the molten metal. Metal-transfer conduits other than a discharge incorporated in a pump base are also disclosed, as are pumps including either a discharge or other metal-transfer conduit according to the invention.

System for releasing gas into molten metal

The present invention includes a molten metal pump and associated components that enable gas to be released into a stream of molten metal. The gas may be released into the molten metal stream (preferably into the bottom of the stream) flowing through a passage. Such a stream may be within the pump discharge and/or within a metal-transfer conduit extending from the pump discharge. The gas is released by using a gas-transfer foot that is positioned next to and is preferably attachable to the pump base or to the metal-transfer conduit. Preferably, the conduit (and/or discharge) in which the gas is released comprises two sections: a first section having a first cross-sectional area and a second section downstream of the first section and having a second cross-sectional area, wherein the second cross sectional area is larger than the first cross-sectional area. Preferably, the gas is released into or near the second section so that the gas is released into an area of relatively lower pressure.

Gas-transfer foot

A system for adding gas to and transferring molten metal from a vessel and into one or more of a ladle, ingot mold, launder, feed die cast machine or other structure is disclosed. The system includes at least a vessel for containing molten metal, an overflow (or dividing) wall, a device or structure, such as a molten metal pump, for generating a stream of molten metal, and one or more gas-release devices.

System and method for degassing molten metal

Immersion pump having slight bulk, for liquid metals, operating by conduction, consisting of one or two magnetic circuits, a conduction loop made of liquid metal and of two electrodes limiting the liquid metal duct in the active zone. A refractory material is cast round the components of the pump, and protects them against the corrosive action of the liquid metal. The part which is not immersed comprising the induction windings of the magnetic circuits is protected by a cast aluminum steel housing.

Immersion pump for pumping corrosive liquid metals

Conduction pump having slight bulk, in which a section of the liquid metal flow subjected to magnetic induction is crossed at the same time by a current, characterized in that the said section of liquid metal flow is limited on two opposite sides by electrodes connected to a current generator circuit, whereas the other sides are made of refractory material. The electrodes are made of a metal of the VIth group of the periodic classification of elements, protected on the corrosive liquid metal side by a boride or an aluminide, or else the electrodes are made of a refractory material soaked with liquid metal.

Carbonnel H

Papers

Immersion pump for pumping corrosive liquid metals

Conduction pump for conveying corrosive metals