Patent ID: 6864199

Claim:
A dry refractory composition, comprising: a dry refractory mixture including a matrix material having a particle size less than 100 mesh in an amount from 20 to 100 weight percent, the matrix material being selected from calcined alumina, fused alumina, sintered magnesia, fused magnesia, silica fume, fused silica, silicon carbide, boron carbide, titanium diboride, zirconium boride, boron nitride, aluminum nitride, silicon nitride, ferro silicon nitride, Sialon, titanium oxide, barium sulfate, zircon, a sillimanite group mineral, pyrophyllite, fireclay, carbon, wollastonite, calcium fluoride, spinel, chromium oxide, olivine, a calcium aluminate aggregate, an alumina-zirconia silicate, chromite, calcium oxide, dolomite, and mixtures thereof, and a dense refractory aggregate having a particle size greater than or equal to 100 mesh in an amount from 0 to 80 weight percent, the dense refractory aggregate being selected from calcined fireclay, calcined Chamotte, a sillimanite group mineral, calcined bauxite, pyrophyllite, silica, zircon, baddeleyite, chromite, dolomite, olivine, cordierite, silicon carbide, sintered alumina, fused alumina, fused silica, sintered mullite, fused mullite, fused zirconia, sintered zirconia mullite, fused zirconia mullite, sintered magnesia, fused magnesia, sintered spinel, fused spinel, dense refractory grog, a chrome-alumina aggregate, a calcium aluminate aggregate, an alumina-zirconia silicate, and mixtures thereof, the matrix material and dense refractory aggregate being selected so that when the dry refractory composition is installed in powder form without addition of water or liquid chemical binders in a void adjacent to a heat source, at least a first portion of the composition near the heat source forms strong thermal bonds; and metal fibers in an amount of 0.5 to 15 weight percent of the dry refractory mixture.