BLEND FOR MANUFACTURING CHAMOTTE REFRACTORY MATERIALS Russian patent published in 2003 - IPC

FIELD: manufacture of building materials. SUBSTANCE: blend contains 65-80% chamotte, 19.5-34% refractory clay, and 0.5-1.0% of naturally occurring topaz as caking additive. Topaz rock finely divided to particle size below 0.063 mm, in order to be uniformly distributed throughout the bulk of blend, is added together with clay clinker required to moisten blend until moisture content attains 6-8%. Products are formed by dry-pressing technique at pressures 60-80% and then baked at 1320-1350 C. EFFECT: increased mechanical strength, heat resistance, and refractoriness of products at lower baking temperature due to intensified caking of clay-chamotte compositions and higher content of needled mullite. 3 tbl