What types of silica alumina refractory bricks are included?
(1) Silica bricks: refer to refractory bricks containing more than 293% SiO, and are the main varieties of acid refractory bricks. It is mainly used for building coke ovens, and also used for the vaults and other load-bearing parts of thermal kilns for various glass, ceramics, carbon calciners, and refractory bricks. It is also used in the high-temperature load-bearing parts of hot blast stoves, but not Used in thermal equipment below 600°C and with large temperature fluctuations.
(2) Clay bricks: Clay bricks are mainly composed of mullite (25%-50%), glass phase (25%-60%), cristobalite and quartz (up to 30%). Usually hard clay is used as the raw material, the mature material is pre-calcined, and then mixed with soft clay, which is formed by semi-dry or plastic method, and the temperature is 1300～1400 C to burn clay brick products. You can also add a small amount of water glass, cement and other binders to make unburned products and amorphous materials. It is a refractory brick commonly used in blast furnaces, hot blast stoves, heating furnaces, power boilers, lime kilns, rotary kilns, ceramics and refractory brick firing kilns.
(3) High alumina refractory brick: The mineral composition of high alumina refractory brick is corundum, mullite and glass phase. Its content depends on the ratio of AL2O3/SiO2 and the type and quantity of impurities. The refractory bricks can be classified according to the content of AL2O3. The raw materials are high alumina bauxite and sillimanite natural ores, as well as those mixed with fused corundum, sintered alumina, synthetic mullite, and clinker calcined with alumina and clay in different proportions. It is mostly produced by sintering method. But the products also include fused cast bricks, fused grain bricks, unburned bricks and unshaped refractory bricks. High alumina refractory bricks are widely used in the steel industry, non-ferrous metal industry and other industries.
(4)Corundum refractory brick: Corundum brick refers to a kind of refractory brick with the content of AL2O3 not less than 90% and the main phase of corundum. It can be divided into sintered corundum brick and fused corundum brick.