Air filter is a kind of filter, also known as air filter cartridge, air filter and so on. It is mainly used for air filtration in engineering locomotives, automobiles, agricultural locomotives, laboratories, sterile operation rooms and various precision operation rooms. The engine in the process of work to suck in a large amount of air, if the air is not filtered, the dust suspended in the air is sucked into the cylinder, it will accelerate the wear of the piston group and the cylinder.