The oil filter is divided into full-flow type and split-flow type. Filtr pełnoprzepływowy jest podłączony szeregowo pomiędzy pompą oleju a głównym kanałem olejowym, so it can filter all the lubricating oil that enters the main oil passage. The split-flow filter 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 wear debris, pył, carbon deposits and colloidal deposits oxidized at high temperature, water, itp. are constantly mixed into the lubricating oil. The function of the oil filter is to filter out these mechanical impurities and colloids, keep the lubricating oil clean, and extend its service life.

 

 

The oil filter should have strong filtering capacity, niski opór przepływu, i długą żywotność. Ogólnie, several filters with different filter capabilities are installed in the lubrication system—collecting filter, coarse filter and fine filter, which are respectively connected in parallel or in series in the main oil passage. (The one connected in series with the main oil passage is called a full-flow filter. When the engine is working, all lubricating oil is filtered through the filter; the one connected in parallel is called a split-flow filter). The coarse filter 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 with a particle size of 0.05mm or more in the oil, and the fine filter is used to filter out fine impurities with a particle size of 0.001mm or more.

Technical characteristics of oil filter:
• Filter paper: Filtry oleju mają wyższe wymagania dotyczące bibuły filtracyjnej niż filtry powietrza, głównie dlatego, że temperatura oleju jest różna 0 do 300 stopni. Under severe temperature changes, stężenie oleju również się odpowiednio zmienia. It will affect the filtering 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 sealing ring: The filter sealing ring of high-quality engine oil is made of special rubber to ensure 100% oil-free leakage.
• Backflow suppression valve: dostępne wyłącznie w wysokiej jakości filtrach oleju. When the engine is turned off, może to zapobiec wysychaniu filtra oleju; when the engine is re-ignited, it immediately generates pressure to supply oil to lubricate the engine. (Also called check valve)
• Relief valve: dostępne wyłącznie w wysokiej jakości filtrach oleju. When the external temperature drops to a certain value or when the oil filter exceeds the normal service life, zawór przelewowy otworzy się pod specjalnym ciśnieniem, umożliwiając przepływ niefiltrowanego oleju bezpośrednio do silnika. Even so, the impurities in the oil will enter the engine together, but the damage is much smaller than the damage caused by the absence of oil in the engine. W związku z tym, the overflow valve is the key to protect the engine in an emergency. (Also known as bypass valve)