Abstract: A refractory assembly for use in a roof in an ore reduction furnace is provided having a pair of refractory blocks with matchable corrugated surfaces. A corrugated plate is provided, with its corrugations having the same wavelength as and a different amplitude than the block corrugations. The plate is bound between the corrugated surfaces of the blocks so that the blocks are spaced apart by and supported on the plate. In the preferred embodiment, the corrugations are sine waves with the plate sine wave having an amplitude greater than the sine wave of the blocks. The entire assembly may be suspending as part of a furnace roof.

Abstract: A conventional glass tank furnace used in the manufacture of glass is provided with a system for recovering heat which inevitably escapes from the furnace roof or crown above the melting and refining tanks of the furnace. A heat recovery plenum means is mounted on top of the furnace roof or crown, and an air blower supplies cool air to the plenum means through a first duct means. The cool air directed to the plenum means cools the furnace crown and in the case of a suspended flat arch crown, the supporting steel work. The cool air in the plenum means is heated by heat escaping from the furnace crown, and thereafter is directed through second duct means to a main combustion air blower where the heated air from the plenum means is mixed with primary combustion air and directed to the furnace and to the furnace burners. Control means are provided to maintain the air in the plenum means at positive pressure so as to prevent air in the furnace from escaping through the furnace crown.

Abstract: The brick lining of a furnace or other high temperature enclosure is veneered by adhesively securing to the brick lining 10 blocks 11 of ceramic fiber material that have been made by a vacuum casting process and have been pre-fired prior to installation. An undercut rabbet 13 may be provided along the periphery of the cold face of the blocks to provide an additional key between the adhesive and the blocks. A jointing layer 14 of a resilient ceramic fiber felt is disposed between the side faces of adjoining blocks.