Oil filter, also known as oil grid. It is used to remove impurities such as dust, metal particles, carbon deposits and soot particles in the oil to protect the engine.
An oil filter is a filter designed to remove contaminants from engine oil, transmission oil, lubricating oil, or hydraulic oil. Oil filters are used in many different types of hydraulic machinery. A chief use of the oil filter is in internal-combustion engines in on- and off-road motor vehicles, light aircraft, and various naval vessels. Other vehicle hydraulic systems, such as those in automatic transmissions and power steering, are often equipped with an oil filter. Gas turbine engines, such as those on jet aircraft, also require the use of oil filters. Aside from these uses, oil production, transport, and recycling facilities also employ filters in the manufacturing process.
Oil filters are available in full flow and split flow. The full-flow filter is connected in series between the oil pump and the main oil passage, so that all the oil entering the main oil passage can be filtered. The split type cleaner is connected in parallel with the main oil passage to filter only part of the lubricating oil sent by the oil pump.
During the working process of the engine, metal grinding debris, dust, oxidized carbon deposits and colloidal deposits at high temperatures, water, etc. are constantly mixed into the lubricating oil. The function of the oil filter is to filter out these mechanical impurities and colloids, to keep the lubricating oil clean and to extend its service life. The oil filter should have strong filtration capacity, low flow resistance and long service life. In general lubrication systems, filters with several different filtration capacities – collectors, strainers and fine filters – are connected in parallel or in series in the main oil gallery. (The full-flow filter is connected in series with the main oil passage. When the engine is working, the lubricating oil is completely filtered by the filter; the shunt filter is connected in parallel with it). The strainer is connected in series in the main oil passage, which is a full flow type; the fine filter is connected in parallel in the main oil passage, which is a split flow type. Modern car engines generally only have a filter and a full-flow oil filter. The coarse filter filters out impurities having a particle diameter of 0.05 mm or more, and the fine filter filters out fine impurities having a particle diameter of 0.001 mm or more.
● Filter paper: The oil filter requires higher filter paper than the air filter, mainly because the temperature change of the oil varies from 0 to 300 degrees. Under severe temperature changes, the oil concentration also changes accordingly. Will affect the filtration flow of the oil. The filter paper of a high-quality oil filter should be able to filter impurities under severe temperature changes while ensuring sufficient flow.
●Rubber seal: The filter seal of high-quality oil is made of special rubber to ensure 100% oil leakage.
● Reflow suppression valve: only available in high quality oil filters. When the engine is turned off, it prevents the oil filter from drying out; when the engine is re-ignited, it immediately generates pressure and supplies oil to the engine. (also known as check valve)
● Overflow valve: Only available in high quality oil filters. When the external temperature drops to a certain value or when the oil filter exceeds the normal service life, the relief valve will open under special pressure, allowing unfiltered oil to flow directly into the engine. Despite this, the impurities in the oil will enter the engine together, but the damage is much smaller than the damage caused by the lack of oil in the engine. The relief valve is therefore the key to protecting the engine in an emergency. (also known as bypass valve)