BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present application generally relates to refractory lining structures used in metallurgical vessels.

(2) Description of the Related Art

The information described in this background section is not admitted to be prior art.

In metallurgical processes, such as casting, molten metal is transported between unit operations in metallurgical vessels. For example, in continuous casting processes, molten steel is tapped from a steelmaking furnace into a ladle. The ladle functions as a transporting vessel within which the molten steel moves from the steelmaking furnace to a casting platform. At the casting platform, the molten steel transfers from the ladle to a tundish. The tundish functions as a metering device that distributes the molten steel through one or more nozzles into molds in a continuous flow.

Metallurgical vessels, such as, for example, ladles and tundishes, must physically contain molten metal at relatively high temperatures, for example, in steelmaking processes, at temperatures greater than 1400° C. (2552° F.). Additionally, the molten metal-contacting surfaces of metallurgical vessels should be as chemically inert as possible with respect to the molten metal contained within the vessels. Accordingly, metallurgical vessels are lined with refractory materials to provide physically-stable and chemically-stable molten metal-contacting surfaces and insulation between the molten metal and the vessel shells, which are typically made of solid steel and therefore susceptible to overheating and loss of mechanical integrity if contacted by molten metal.

A variety of refractory products have been developed for metallurgical vessel linings. Nevertheless, enhanced refractory lining structures for metallurgical vessels, which provide improved mechanical stability and structural integrity during use, would be advantageous.

BRIEF SUMMARY OF THE INVENTION

The invention described in this specification is directed to refractory lining structures for metallurgical vessels. The invention described in this specification is also directed to metallurgical vessels comprising the refractory lining structures, methods for making the refractory lining structures and for making metallurgical vessels comprising the refractory lining structures, and methods of using metallurgical vessels comprising the refractory lining structures in metallurgical processes. The refractory lining structures provide improved mechanical stability and structural integrity, characterized by, for example, decreased cracking, delamination, and spalling of working linings from underlying back-up 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 comprises a first layer and a second layer underlying at least a portion of the first layer. The first layer and the second layer both have a first surface facing away from a sidewall of a metallurgical vessel and a second surface located opposite the first surface and facing toward the sidewall of the metallurgical vessel. The second surface of the first layer contacts the first surface of the second layer. The first layer comprises a first refractory material, and the second layer comprises a second refractory material. At least one elongated expansion joint is formed in the first surface of the first layer and extends through the first surface of the first layer in a substantially vertical direction.

