Light weight heat resistant refractory bricks have high porosity, small volume, and low thermal conductivity, but have good heat insulation performance. Some high end light weight heat insulated bricks can also be used directly as working layers.
Then there are many types of thermal insulation refractory bricks:
1. Alumina insulation refractory bricks: Alumina insulation refractory bricks are made of fused corundum and sintered alumina as the main raw materials. It has the characteristics of resistance to acid, alkali, gas, oxygen and reduction, and good thermal shock resistance. It can be used for a long time at 1650-1800℃.
2. High alumina heat resistant refractory bricks: high alumina heat resistant refractory bricks are heat resistant refractory bricks with an aluminum content of 48%. The raw materials are heat-resistant refractory bricks made of bauxite raw materials, clay, and a binder. General heat-insulating high-alumina bricks can be used in areas where the temperature is not higher than 1350℃ without material erosion.
3. Mullite insulation refractory bricks: Mullite insulation refractory bricks can directly contact the flame, and have the characteristics of high temperature resistance, good strength and remarkable energy saving effect, and are suitable for heating furnaces, hot air furnaces and ceramic roller kilns. Used in furnace lining not exceeding 1550℃.
4. Insulating clay refractory bricks: Insulating clay bricks are made of clay and floating beads with aluminum content of 30-48% as the main raw materials, and are formed by sintering. The volume density of heat-insulating clay brick is between 0.3-1.5, generally 1.0 is used more, and the amount of heat-insulating clay brick is more than half of the heat-insulating refractory brick. The temperature range is between 1000-1200℃.
5. Silica thermal insulation refractory bricks: The silicon content of the silica thermal insulation refractory bricks is more than 90%, and the load softening temperature is high, but the volume will expand slightly during the heating process. Silica thermal insulation refractory bricks are used at temperatures below 1550℃. In comparison, the amount of silica thermal insulation refractory bricks is smaller than that of clay thermal insulation refractory bricks.
6.Diatomite insulation refractory bricks: diatomite insulation refractory bricks are mainly made of diatomite, the advantage is good insulation performance, but afraid of moisture. Use heat insulation layer with temperature below 900℃.
7. Expanded perlite heat-resistant refractory bricks: Expanded perlite heat-resistant refractory products are made of perlite as raw material, and the refractoriness is not high. The maximum use temperature is below 1000℃.
