In today's rapidly developing economy, insulation materials are of great significance for improving people's work and living environment, and saving energy.
The ability to achieve insulation mainly depends on its heat transfer characteristics. Non gases (excluding hydrogen) with low thermal conductivity in nature are substances with low thermal conductivity and low thermal capacity under static conditions. The thermal conductivity of ceramic fibers is basically close to that of gas, because ceramic fibers are interwoven with solid fibers, filled with gas, and the porosity reaches 90%.
The heat transfer of materials such as ceramic fiber boards is influenced by the following factors:
1. Effect of porosity
Insulation materials have better porosity or bulk density at each temperature of use, and have good insulation effects within this range. Therefore, ceramic fiber boards are divided into several levels based on their usage temperature, and the density is adjusted accordingly in the range of 260 to 350 according to the usage situation.
2. Atmospheric impact
The low thermal conductivity of ceramic fiber boards is based on the premise of most gases, but if there are high heat gases such as hydrogen or helium in the usage environment, ceramic fiber products are not suitable.
3. The impact of packing density
For ceramic fibers, in order to maintain low thermal conductivity, the preferred density of ceramic fiber products is below 250kg/m3, and the porosity is above 90%.
4. Directional impact
In the forming process of ceramic fiber board, the length and width directions of the area are the main directions. Moreover, the thermal conductivity of the front side of the fiber product is much smaller than that of the side. Therefore, during the application process, the back side of the fiber product is close to the furnace wall, and the front side is a high-temperature contact surface. Therefore, the fiber product cannot be installed perpendicular to the furnace wall.