Fire clay refractory castable is a specific indicator of the clay requirements: AL2O3 is 29% to 35%, Fe2O3 less than 1.8%, K2O less than 1.1%, burning to 10% to 14%, refractor degree greater than 1670 ℃, Wide sintering temperature range, in the mineral composition should contain a small amount of montmorillonite and mica and other substances, so that it has a good combination and plasticity. Clay after grinding less than 0.088mm should account for more than 60%, the amount of 7% to 13%. Refractory aggregate application of clay clinker and high bauxite clinker, the largest size of 10mm, the general aggregate accounted for about 70%, fine powder selection stunt or a high bauxite clinker for grinding, and sometimes mixed Alumina powder or corundum powder, less than 0.088mm accounted for more than 85%, in the castables accounted for 17% to 25%. Addition of more varieties, according to the characteristics of clay and construction requirements, as a hardening agent, the general use of high alumina cement or calcium aluminate cement, the amount of 0.2 to 3.0%, in the clay colloid dispersion, add alkali metal ions As a dispersant, can form alkali ions - clay, because the alkali is positively positive, the potential difference between the clay particles between the repulsion, more than the van der Waals gravity, that is, more cations of the clay, the particle interval increases, thus Promote the gel colloid gel, release free water, and enhance the flowability of castable, is conducive to mixing molding. In order to improve the performance of castables, sometimes add ultrafine powder and kyanite and other admixtures. Clay with castable and cement combined with castable, with a high temperature strength, high thermal strength, high temperature stability and good resistance to stripping and so on.