P84 needle felt is made of P84 fiber (i.e. polyimide fiber) produced by LENZING Company of Austria through three-dimensional needle punching. It has good high temperature resistance, up to 280°C, and the cross section of P84 fiber is irregular leaf-shaped, which can greatly improve the filtering effect. The fiber itself has certain resistance to hydrolysis and oxidation. The product has good temperature resistance and good filtering effect, and is widely used in concrete mixing, cement, garbage incineration, coal-fired boilers and other complex working conditions.