The Use and Types of Anhui Lightweight Refractory Bricks - Produced by Chongde Refractory Manufacturers
The Use and Types of Anhui Lightweight Refractory Bricks - Produced by Chongde Refractory Manufacturers
Lightweight refractory bricks belong to a type of refractory bricks, mainly used for lining various thermal kilns such as electric furnace roofs, blast furnaces, hot blast furnaces, steel ladles, steel drums, hot metal carts, cement kilns, glass kilns, boilers, etc. due to their low density, high porosity, low thermal conductivity, and good insulation performance. Widely used in industries such as ironmaking, steelmaking, chemical engineering, cement, etc., lightweight insulation bricks have high strength, good rigidity, lightweight seismic resistance, wind pressure resistance, creep resistance, superior performance, reduced building load, and are more economical and durable.
Lightweight refractory bricks can be divided into the following types according to their types:
1. Clay insulation bricks. It is a thermal insulation refractory product with an Al2O3 content of 30%~48%, mainly made from refractory clay. Its production process adopts burn out addition method and foam method. Lightweight clay insulation bricks have a wide range of applications, mainly used as refractory materials for insulation layers in various industrial kilns that do not come into contact with molten materials or have no corrosive effects. The operating temperature is between 1200~1400 ℃.
2. Diatomaceous earth bricks: Compared with other lightweight insulation bricks, diatomaceous earth bricks have lower thermal conductivity. Its usage temperature varies with purity. It is generally below 1100 ℃ because the shrinkage deformation of the product is relatively large at high temperatures. When using pure diatomaceous earth raw materials, it needs to be fired at a higher temperature, and silicon dioxide can be converted into quartz. Lime can also be added as a binder and mineralizer to promote the conversion of quartz during firing, which is beneficial for improving the heat resistance of the product and reducing impact shrinkage at high temperatures.
3. Aluminum oxide insulation bricks. The product has high fire resistance and good heat shock resistance, and is commonly used as a high-temperature insulation layer for kilns. The operating temperature is 1350-1500 ℃. Thermal insulation and refractory products mainly made from fused corundum, sintered alumina, and industrial alumina as raw materials.
4. Lightweight mullite bricks. Thermal insulation and refractory products made from mullite as the main raw material. Mullite thermal insulation bricks have high temperature resistance, high strength, low thermal conductivity, and can directly come into contact with flames, making them suitable for lining various industrial kilns.
5. Aluminum oxide hollow ball bricks. Aluminum oxide hollow ball bricks are mainly used for long-term use below 1800 ℃. It also has good chemical stability and corrosion resistance at high temperatures. Compared with other lightweight insulation bricks, alumina hollow ball bricks have higher safe use temperature, greater strength, and lower thermal conductivity. The volume density is also 50%~60% lower than that of dense products of the same composition, and can withstand the impact of high-temperature flames.
6. Lightweight silica bricks. Lightweight siliceous thermal insulation bricks are thermal insulation refractory products with a SiO2 content of no less than 91%, mainly made from silica. The volume of lightweight silica thermal insulation bricks is 0.9~1.1g/cm3, and the thermal conductivity is only half of that of ordinary silica bricks. It has good thermal shock resistance, and its starting temperature for load softening can reach 1600 ℃, which is much higher than that of clay thermal insulation bricks. Therefore, the use temperature of siliceous insulation bricks can reach 1550 ℃. It does not shrink at high temperatures, and even has slight expansion. Lightweight silica bricks generally use crystalline quartzite as the raw material, and flammable substances such as coke, anthracite, sawdust, etc. are added to the mix, or porous structures are formed by gas foaming method