Classification of lightweight insulation bricks for glass ki

Lightweight thermal insulation bricks for glass kiln can be divided into 6 categories according to their raw materials. Among them, lightweight silica brick and diatomite brick are the most widely used. Lightweight thermal insulation bricks have the advantages of good thermal insulation performance, but have poor pressure resistance, slag resistance and thermal shock resistance, so they cannot be in direct contact with glass or flame.
 
Lightweight silica brick. The light-weight silicon heat-insulating brick is an insulating refractory product made of silica as a main raw material and having a SiO2 content of not less than 91%. The weight of the lightweight silicon heat-insulating brick is 0.9~1.1g/cm3, and the thermal conductivity is half of that of ordinary silica brick. It has good thermal shock resistance, and its load softening start temperature can reach 1600°C, which is much higher than clay heat-insulating brick. . Therefore, the maximum temperature of the silicon insulation brick can reach 1550 °C. Does not shrink at high temperatures, and even has a slight expansion. Lightweight silica bricks generally use crystalline quartzite as raw material, and flammable substances such as coke, anthracite, sawdust, etc. are added to the batch, or a porous structure is formed by a gas foaming method. Diatomite bricks: Diatomite bricks have a lower thermal conductivity than other lightweight insulation bricks. Its use temperature varies with purity. Generally, it is below 1100 ° C, because the shrinkage deformation of the product is large at high temperatures. When using pure diatomaceous earth raw materials, it needs to be fired at a higher temperature, silica is converted into tridymite, and lime can also be added as a binder and mineralizer to promote the conversion of squamous quartz during firing, which is beneficial to Improve the heat resistance of the product and reduce the heat shrinkage at high temperatures.
 
Clay insulation bricks. It is made of refractory clay as the main raw material and has an Al2O3 content of 30%~48%. The production process uses a burn-in addition method and a foam method. Lightweight clay heat-insulating bricks are widely used in various industrial furnaces without contact with molten materials and other non-erosion protective refractories. The service temperature is 1200~1400 °C.