A device to remove particulate impurities in the air. When piston machinery (internal combustion engine, reciprocating compressor, etc.) is working, if the inhaled air contains dust and other impurities, it will aggravate the wear of the parts, so air filters must be installed.

The air filter consists of two parts: a filter element and a shell. The main requirements of an air filter are high filtration efficiency, low flow resistance, and continuous use for a long time.

main effect

The engine needs to suck in a large amount of air during the working process. If the air is not filtered, the dust suspended in the air is sucked into the cylinder, which will accelerate the wear of the piston assembly and the cylinder. Larger particles entering between the piston and the cylinder will cause serious cylinder pull phenomenon, which is especially serious in a dry and sandy working environment. The air filter is installed in the front of the intake pipe to filter out dust and sand particles in the air, ensuring that sufficient and clean air enters the cylinder.

Among the thousands of parts and components of the car, the air filter is an extremely inconspicuous component, because it is not directly related to the technical performance of the car, but in the actual use of the car, the air filter is (Especially the engine) has a great impact on the service life.

On the one hand, if there is no filtering effect of the air filter, the engine will inhale a large amount of air containing dust and particles, resulting in serious wear and tear of the engine cylinder; on the other hand, if it is not maintained for a long time during use, the air filter The filter element of the cleaner will be filled with dust in the air, which will not only reduce the filtering capacity, but also hinder the circulation of air, resulting in excessively thick air mixture and abnormal operation of the engine. Therefore, regular maintenance of the air filter is essential.

Air filters generally have two types: paper and oil bath. Because paper filters have the advantages of high filtration efficiency, light weight, low cost, and convenient maintenance, they have been widely used. The filtration efficiency of the paper filter element is as high as 99.5%, and the filtration efficiency of the oil bath filter is 95-96% under normal conditions.

The air filters widely used in cars are paper filters, which are divided into dry and wet types. For the dry filter element, once it is immersed in oil or moisture, the filtration resistance will increase sharply. Therefore, avoid contact with moisture or oil when cleaning, otherwise it must be replaced with a new one.

When the engine is running, the air intake is intermittent, which causes the air in the air filter housing to vibrate. If the air pressure fluctuates too much, it will sometimes affect the engine’s intake. In addition, the intake noise will be increased at this time. In order to suppress the intake noise, the volume of the air cleaner housing can be increased, and some partitions are arranged in it to reduce resonance.

The filter element of the air cleaner is divided into two types: dry filter element and wet filter element. The dry filter element material is filter paper or non-woven fabric. In order to increase the air passage area, most of the filter elements are processed with many small folds. When the filter element is slightly fouled, it can be blown with compressed air. When the filter element is seriously fouled, it should be replaced with a new one in time.

The wet filter element is made of sponge-like polyurethane material. When installing it, add some engine oil and knead it by hand to absorb foreign matter in the air. If the filter element is stained, it can be cleaned with cleaning oil, and the filter element should be replaced if it is overly stained.

If the filter element is severely blocked, the air intake resistance will increase and the engine power will decrease. At the same time, due to the increase in air resistance, the amount of gasoline sucked in will also increase, resulting in an excessively rich mixture ratio, which will deteriorate the engine’s operating state, increase fuel consumption, and easily produce carbon deposits. You should get into the habit of checking the air filter element frequently.