A refractory ring structure for forming a section of an inner wall or liner of a metallurgical vessel is provided. The refractory ring structure comprises a continuous top surface; a continuous bottom surface; a continuous arcuate inner surface extending from the top surface to the bottom surface and defining a cavity; a continuous arcuate outer surface opposite the inner surface and extending between the top surface and the bottom surface; and a continuous protrusion or a plurality of protrusions extending from the inner surface for lifting the ring structure. The refractory ring structure comprises a heat resistant, refractory material suitable for use in the inner wall of a metallurgical vessel. Also provided herein are a metallurgical vessel comprising a refractory ring structure as disclosed herein, and a method for providing or replacing all or a section of a refractory inner wall or liner of a metallurgical vessel.

A refractory lining structure for a metallurgical vessel is characterized by at least one elongated expansion joint formed in and extending through the surface of the working lining in a substantially vertical direction. The elongated expansion joint accommodates thermal expansion of the working lining in a metallurgical vessel such as, for example, a tundish during preheating for a continuous casting operation. The elongated expansion joint decreases crack formation, delamination, and spalling of the working lining from underlying back-up linings and/or safety linings in metallurgical vessels during preheating and use, while still facilitating metal skull removal after the completion of metallurgical operations.

A refractory lining structure for a metallurgical vessel is characterized by at least one elongated expansion joint formed in and extending through the surface of the working lining in a substantially vertical direction. The elongated expansion joint accommodates thermal expansion of the working lining in a metallurgical vessel such as, for example, a tundish during preheating for a continuous casting operation. The elongated expansion joint decreases crack formation, delamination, and spalling of the working lining from underlying back-up linings and/or safety linings in metallurgical vessels during preheating and use, while still facilitating metal skull removal after the completion of metallurgical operations.

A melting and holding furnace includes a main body and a material input mechanism supplying a molten metal to the body which includes a melting chamber; a molten metal receiving chamber; a pumping-out chamber; and a molten metal heating mechanism. The input mechanism includes a molten-metal surface level sensor to detect that the surface height position of the metal in the pumping-out chamber has reached a lower limit that is set to be above the lower surface height position of a lid of the melting chamber, and is set to supply the receiving chamber with the metal and/or the metal block when the sensor detects that the surface height position of the metal in the pumping-out chamber has reached the lower limit so that the surface height position of the metal in the pumping-out chamber is always kept above the lower surface height position of the lid.

The present invention provides a crucible for melting and casting a metal fuel, which includes a reaction preventing layer including: LaYO.sub.3; or ZrO.sub.2 containing a Y.sub.2O.sub.3 stabilizer at 5 to 10 wt %, and a method of melting and casting a metal fuel using the same.

The present invention provides a crucible for melting and casting a metal fuel, which includes a reaction preventing layer including: LaYO.sub.3; or ZrO.sub.2 containing a Y.sub.2O.sub.3 stabilizer at 5 to 10 wt %, and a method of melting and casting a metal fuel using the same.

A lightweight polymer-based composite product may include a polymer material body and a lightweight filler material that is embedded in the polymer. The polymer material body may be an in-situ polymerized polymer formed via casting of a reactive resin in a mold. The polymer may have a density of at least 1.0 g/cm.sup.3. The lightweight filler material may be concentrated on at least a portion of a first surface of the polymer material body. The lightweight filler material may have a density of between 0.1 and 1.0 g/cm.sup.3. The lightweight polymer-based composite product may have a density that is less than a comparable product that consists mainly of the polymer.

A lightweight polymer-based composite product may include a polymer material body and a lightweight filler material that is embedded in the polymer. The polymer material body may be an in-situ polymerized polymer formed via casting of a reactive resin in a mold. The polymer may have a density of at least 1.0 g/cm.sup.3. The lightweight filler material may be concentrated on at least a portion of a first surface of the polymer material body. The lightweight filler material may have a density of between 0.1 and 1.0 g/cm.sup.3. The lightweight polymer-based composite product may have a density that is less than a comparable product that consists mainly of the polymer.

The invention relates to systems for transferring molten metal from one structure to another. Aspects of the invention include a transfer chamber constructed inside of or next to a vessel used to retain molten metal. The transfer chamber is in fluid communication with the vessel so molten metal from the vessel can enter the transfer chamber. A powered device, which may be inside of the transfer chamber, moves molten metal upward and out of the transfer chamber and preferably into a structure outside of the vessel, such as another vessel or a launder.

The invention relates to systems for transferring molten metal from one structure to another. Aspects of the invention include a transfer chamber constructed inside of or next to a vessel used to retain molten metal. The transfer chamber is in fluid communication with the vessel so molten metal from the vessel can enter the transfer chamber. A powered device, which may be inside of the transfer chamber, moves molten metal upward and out of the transfer chamber and preferably into a structure outside of the vessel, such as another vessel or a launder.