Foam ceramic filter is the most obvious in rectification, mechanical filter, filter cake filtration, adsorption and so on. Comparison of technology and economy: structure of ceramic foam filter complex, high strength, complete specifications, high porosity, using the best effect; straight hole filter has high strength, the use effect is secondary; fiber filter has the advantages of simple structure, convenient use, strength and filtering effect is far less than the former two. 

 Fiber filter screen for casting according to different scope, can be divided into molten steel, molten iron, aluminum liquid with glass fiber filter; according to different shapes can be divided into sheet, circular, spherical, and cylindrical cap type filter screen; according to the use of different materials can be divided into non alkali cloth, high silicon oxygen mesh. Aluminum borate silicate glass composition, the content of alkali metal oxide (mass fraction) is less than 0.8%. High silica cloth with high silica glass fiber woven mesh, prepared by a series of postprocessing, with excellent characteristics of high temperature resistance, high tensile strength, good adsorption properties, widely used in the production of casting filter mesh, filter net shaped casting. The product standard of high silica glass fiber filter cloth is more than or equal to 96%. Aluminum fiber filter screen for selecting non alkali cloth; cast iron, cast steel is commonly used in fiber filters with high silica glass fiber cloth. 

 The liquid steel fiber filters suitable for small and medium sized steel castings and large cast iron filter, liquid iron fiber filter is suitable for gray iron castings, ductile iron and copper and aluminum and other non-ferrous alloy filter. Aluminum liquid fiber filtering net is suitable for the filtration of aluminum alloy casting. Fiber filter can be cut into any size, placed in the pouring cup and runner lap, cross section and ingate lap surface of the press box, generally placed closer to the ingate, filtration and purification effect is better. The section area of the casting system on the filter screen is generally 2-4 times of the section area of the casting system of the filter net. In addition, the casting time of fiber filter for cast steel is controlled within 20s, and the 7-15s is recommended.