Fire resistance of ceramic fiber

In recent years, the application prospect of ceramic fiber in high-temperature firing kilns is expanding day by day. The highest service temperature of refractory felt and blanket products made of ceramic fiber can reach 1649 ℃. It is widely used in various kilns because of its good heat insulation effect, easy to use, especially its small heat storage, which greatly shows a high energy-saving efficiency.

(1) The most important indexes of varieties and ceramic refractory fibers are fiber diameter and thermal stability. Al2O3 SiO2 fiber is commonly used in the ceramic industry. It is divided into different application ranges according to the content of Al2O3. Cr2O3 material is also introduced to improve its fire resistance and oxidation resistance. Generally, the fiber products with high alumina content and low iron oxide and other impurities are pure white, and the fibers with chromium oxide are sold in a milky yellow tone. The average diameter of ceramic fiber is 22-33 microns. Those with fine fiber, low density and low thermal conductivity have high service temperature. If the fiber is thick and dense, the effect is not ideal. The thermal stability index of fiber is more important. The linear shrinkage range of Al2O3-SiO2 fiber products at 1260 ℃ is 35-88%. Shrinkage also directly affects thermal stability Sex.

Due to the low thermal conductivity, low density and light weight of the fiber, the lighter steel frame support structure is used in the design and construction of the kiln, which makes the development of the ceramic kiln enter the era of "kiln lightweight". The fiber has small heat storage, and is suitable for rapid heating and cooling firing. The fiber is flexible and can be processed into products with grooves or openings. It also has good resistance to mechanical vibration and impact, and good chemical stability. These advantages have played an important role in promoting the development of new kilns and the development of ceramic technology and industry.

At present, ceramic fiber products include: felt, blanket, block, bulk fiber, fiber paper and vacuum formed products. The working range is generally 871-1427 ℃, and can be used at high temperatures above the limit temperature for a short time under special circumstances.