Abstract: A replaceable liner assembly for a blast furnace tuyere comprises a tubular, metallic liner which fits within the tuyere and a plurality of layers of refractory fiber paper sandwiched between the tubular liner and the inside surface of the tuyere. There are gas-tight seals between the liner and the tuyere at opposite ends thereof to prevent gas from entering the space occupied by the refractory fiber paper. The liner is composed of a metal which has a good resistance to oxidation and a lower thermal conductance and higher melting point than the metal of which the tuyere is composed.

Abstract: A furnace bottom construction comprises refractory blocks resting atop a seal in turn resting on the top surface of a layer of ramming material in which are embedded cooling ducts resting on a concrete foundation. The seal is composed of thin, fluid-impervious, flexible, ductile sheet material deformed to follow the contours and indentations of the top surface of the ramming material. The bottom surface of the seal and the top surface of the ramming material are in intimate contact along substantially the entire area of said top surface, with substantially no air gaps between the two.

Abstract: A cooling system for a vessel, such as a blast furnace, containing hot gas. The cooling system comprises a large number of cooling circuits each having one or more cooling members extending inwardly into the blast furnace walls. At the downstream end of each cooling circuit is a device which indicates when a cooling member in that circuit has a leak. Each leak detecting device comprises a container normally filled with water which is displaced from the container by gas from the blast furnace when there is a leak in a cooling member. The displacement of the water by the gas is visually displayed or generates a signal to indicate the occurrence of a leak.