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Explain the structure and principle of oil filter in detail


I believe that when most people buy a car, they try hard to choose the one with the best cost performance and the most suitable for themselves, but they rarely study the later maintenance parts carefully. Today, I will introduce the most basic vulnerable part during maintenance – oil filter, and explain its importance through its structure and working principle.

Now the automobile engine adopts full flow filtration system. What is full flow?

That is, all oil passes through the oil filter, leaving impurities before supply, that is, the engine is filtered from time to time, and every drop of oil is filtered.


There is a pressure difference in the filtration system: the oil inlet pressure is high and the oil outlet pressure is low, which is inevitable. If you wear a mask, it is also a filtering system. You will find the air resistance when breathing.

When the engine oil filter works, there is a pressure difference. The pressure from the oil pump is high and the pressure output to the main lubricating oil passage of the engine is slightly low. Through the filter paper with large filtering capacity or new filter paper, the pressure difference is very small, so it can ensure full flow filtration. If the pressure difference is very large, the oil is blocked at the oil inlet end, the flow at the oil outlet end is small, and the pressure of the main oil passage is also small, which is very dangerous. In order to ensure the pressure supply of the main oil passage, bypass valves are designed at the bottom of the oil filter. When the pressure difference is high to a certain extent, the bypass valve opens, so that the oil directly enters the main oil passage for circulation again without filtering by the filter paper. At this time, it is not full flow filtration, but partial filtration. If the oil sludge and gum cover the surface of the filter paper after the deep oxidation of the oil, it will enter the bypass valve circulation mode without filtration. Therefore, we should change the oil and oil filter regularly! At the same time, choose a good engine oil filter element. Don’t try to be cheap. Buy a filter element with low filter grade.

Several reasons and conditions for opening the bypass valve:
1. There are too many impurities and dirt on the filter paper. The flow can be filtered at small speed, and the flow bypass valve at large speed is opened for partial filtration.
2. After the passing capacity of the filter paper decreases, the oil flow increases sharply – for example, the speed suddenly increases to 4000-5000 rpm, and the bypass valve is opened for partial filtration.
3. If the engine oil is not changed for a long time, the drain hole of the engine oil filter paper is covered or blocked – in this way, the bypass valve of any speed can be opened, and the idle speed can also be opened.
Let’s take a look at the structure drawing and parts drawing of the oil filter so that you can understand it more clearly:

From the above, we can see the importance of oil filter element, so how important it is to choose a good oil filter element for your car. The filter paper with bad filter element has low filtering accuracy and can not achieve filtering effect. If the engine oil is not replaced for a long time, the bypass valve will be opened when the filter is blocked, and it will be directly supplied to the engine without filtering.

Chuangben engine oil filter adopts high-efficiency special filter materials, excellent corrosion resistance, the best fold design, greater pollution capacity and lasting protection of the engine. Effectively filter various polluting particles and impurities into the engine for recycling, and use advanced filtration technology to provide the best protection for engine parts.