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 engine oil to protect the engine.
The oil filter is divided into full-flow type and split-flow type. The full-flow filter is connected in series between the oil pump and the main oil passage, so it can filter all the lubricating oil that enters the main oil passage. The split-flow cleaner is connected in parallel with the main oil passage to filter only part of the lubricating oil sent by the oil pump.
Introduction
During the working process of the engine, metal wear debris, dust, carbon deposits and colloidal deposits oxidized at high temperature, water, etc. are constantly mixed into the lubricating oil. The function of the oil filter is to filter out these mechanical impurities and gums, to keep the lubricating oil clean, and to extend its service life. The oil filter should have strong filtering capacity, low flow resistance, and long service life. Generally, several filters with different filtering capacities are installed in the lubrication system-filter collector, 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). Among them, the coarse filter one 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
●Filter paper: Oil filters have higher requirements for filter paper than air filters, mainly because the temperature of the oil varies from 0 to 300 degrees. Under severe temperature changes, the concentration of the oil will also change accordingly. 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 leakage.
●Backflow suppression valve: only available in high-quality oil filters. When the engine is turned off, it can prevent the oil filter from drying out; when the engine is re-ignited, it immediately generates pressure to supply oil to lubricate the engine. (Also called check valve)
●Relief 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 overflow valve will open under special pressure, allowing unfiltered oil to flow directly into the engine. Nevertheless, 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. Therefore, the overflow valve is the key to protect the engine in an emergency. (Also known as bypass valve)
Replacement cycle
●Installation:
a) Drain or suck up old engine oil
b) Loosen the fixing screws and remove the old oil filter
c) Apply a layer of oil on the sealing ring of the new oil filter
d) Install the new oil filter and tighten the fixing screws
●Recommended replacement cycle: cars and commercial vehicles are replaced once every six months
Automotive requirements for oil filters
Filter precision, filter out all particles> 30 um,
Reduce particles that enter the lubrication gap and cause wear (< 3 um-30 um)
The oil flow rate corresponds to the engine oil demand.
Long replacement cycle, at least longer than the oil life (km, time)
The filtering accuracy meets the requirements of protecting the engine and reducing wear.
Large ash capacity, suitable for harsh environments.
It can adapt to higher oil temperature and corrosive environment.
When filtering the oil, the lower the pressure difference, the better, to ensure that the oil can pass smoothly.
Function
Under normal circumstances, all parts of the engine are lubricated by oil to achieve normal operation, but the metal chips, dust, carbon deposits that are oxidized at high temperature and some water vapor will be continuously mixed in when the parts are running. In the engine oil, the service life of the engine oil will be reduced over time, and the normal operation of the engine may be affected in severe cases.
Therefore, the role of the oil filter is reflected at this time. Simply put, the main function of the oil filter is to filter most of the impurities in the oil, keep the standby oil clean, and extend its normal service life. In addition, the oil filter should also have the performance of strong filtering capacity, low flow resistance, and long service life.
Post time: Nov-12-2021