This kind of nonwoven filter felt possess high porosity, good permeability, high effective dust collecting, long service life etc. Common character as ordinary filter felt have. Besides, owing to its medial temperature resistance (can reach to 150°C in short time), medial anti-acid and anti-alkali, especially its excellent anti-abrasion, polyester needle punched filter felt have the largest quantity of turnouts grams are from 350g/m² to 800g/m², thickness are from 1mm to 3mm, The surface treatment can be divided into singeing, calendaring or coated etc., according to different working conditions.