There are five types firebrick which are widely used for high temperature furnace and kiln. They are as follows:
1.Fireclay brick: As weak acidic material, Its main content is Al2O3 and SiO2 and strong acidic resistance to acidic slag and gas. Refractoriness under high temperature and load could reach to 1350 degrees celsius. It has great stability against the rapid change of temperature. While, the working temperature is not more than 1000 degrees celsius. Fireclay brick is used at various oven, incinerator, cupola, etc.
2.High alumina brick: Made by high grade bauxite and other additives, Its refractoriness under load is normally above 1420-1550 degrees celsius, which is higher than fireclay brick and it increase along with the Al2O3 content enhances. High alumina brick is mainly used at EAF furnace, Glass melting furnace, Cement rotary kiln, Ladle, Hot blast stove, etc.
3.Silica brick: Dense shaped refractory brick and the SiO2 content is more than 93%, Characterize with high strength and acid resistance and good thermal shock, it widely used at coke furnace, hot stove, tunnel kiln, crucible furnace, electric furnace, etc.
4.Light weight fire brick: This kind of brick contains lots of bubble and has good ability of thermal insulation. Such as, clay and high alumina insulation brick, mullite brick, etc. It is mainly used as insulation layer, with the purpose of reducing the heat loss and energy waste. But due to the weak resistance to thermal shock, slag corrosion and lower strength, it can not directly touch flame or slag.
5.Magnesium fire brick: It mainly refers to magnesia brick and magnesia carbon brick, of which the MgO content is more than 85%. As neutral material, its refractoriness under load above 2000 degrees celsius. It mainly used as lining brick for Ladle, EAF, AOD, VOD, especially at slag zone.