Fibrous insulation material has many advantages such as light weight, low thermal conductivity, low heat capacity, good temperature resistance and convenient structure, and has excellent energy saving effect. Fiber insulation materials mainly include inorganic fiber materials and composite fiber materials, and widely used mainly include asbestos, mineral wool, glass fiber and fireproof fiber.
Asbestos is a general term for natural fibrous hydrosilicate minerals that are widely used in industrial raw materials such as thermal insulation, heat preservation, fire protection, insulation and sealing.
Mineral wool is a synthetic mineral fiber insulation material made from naturally occurring minerals such as blast furnace slag, basalt and diabase.
Fiberglass is a fibrous thermal insulation material obtained by passing molten glass through steam injection, flame injection, centrifugation and other methods. According to the shape, it can be divided into continuous long fiber, short fiber, etc. According to the composition, it can be divided into alkali-free glass fiber, alkali-containing glass fiber, and zirconium-containing glass fiber. Long fibers are used for insulation materials, and short fibers are used for plastic reinforcement materials for energy-saving insulation materials.
Aluminosilicate fiber is usually understood as refractory fiber. Use kaolin, fired gemstone or bauxite as raw material and add B2O3 to increase melt viscosity and reduce slag balls. Melt the prepared material in an electric arc furnace or a resistance furnace. At the bottom of the electric furnace, there is a constant temperature working channel, which is heated by electricity to ensure the temperature and viscosity of the molten material.
Formed by injection method, the injection pressure depends on the properties of the raw material and the melting point, usually around 0.6Mpa. The short blown fibers are deposited in the cotton receiving room, bonded and pressed with a binder to form a felt product with a certain strength, and then sewn on a needle-punched machine. Needle-punched felt has a high structural strength. The use temperature of aluminosilicate fiber is less than 1200°C, depending on the content of A1203. For example, add AI203 to the ingredients to make the content of A1203 reach 95% to obtain alumina fibers, or add C2O3, ZO2, etc. to the ingredients to decrease in use temperature Raise to 1400°C. It can also be centrifugally shaped, and a high-speed centrifuge will spin the molten liquid stream into short fibers.
The common ones are alumina fiber, zirconium fiber, etc., which are commonly used as high temperature thermal insulation materials.