Abstract: A metallurgical furnace has an annular conduit or hot blast plenum encircling and formed as a part of the shell of the furnace, and such plenum has a variable venturi throat or passageway through which the wind or hot blast enters the furnace proper. The furnace shell above the plenum is supported by fluid-actuated cylinder-piston means connected to conventional shell supporting legs anchored to a fixed support.

Abstract: In a hot blast stove, a shell structure comprises a checker brick chamber and a common upper portion of the shell embraces a combustion chamber having a length substantially less than the shell structure that is mounted contiguously alongside of and externally to the shell. A refractory lined dome or envelope covers both the checker brick chamber and combustion chamber. Means is provided that supports the combustion chamber and that acts responsively to thermal movement of the combustion chamber; such means existing independently of said shell. In another instance the shell and combustion chamber are self-supporting.