The structure of the diesel filter is roughly the same as that of the oil filter, and there are two types: replaceable type and spin-on type.
However, its working pressure and oil temperature resistance requirements are much lower than that of oil filter, while its filtering efficiency requirements are much higher than that of oil filter. The filter element of the diesel filter is mostly made of filter paper, and some are made of felt or polymer materials. Diesel filter can also be divided into diesel water separator and diesel fine filter. The important function of the oil-water separator is to separate the water in the diesel oil. The presence of water is extremely harmful to the fuel supply system of diesel engines. Rust, wear, seizure and even deterioration of the combustion process of diesel fuel will occur. Due to the high sulfur content in Chinese diesel fuel, when combustion occurs, it will even react with water to form sulfuric acid to corrode engine parts. The traditional way of water removal is mainly sedimentation, through funnel structure. More than three engines with emissions put forward higher requirements for water separation, which requires the use of high-performance filter media. The diesel fine filter is used to filter the fine particles in the diesel fuel. The diesel engine with more than three emissions in the country is mainly aimed at the filtration efficiency of 3-5 micron particles.