The filter element separates solid particles in liquid or gas, or makes different substances fully contact, speeds up the reaction time, and can protect the normal operation of the equipment or the cleanliness of the air. When the fluid enters the filter element with a certain specification of the filter mesh, its impurities are blocked, and the clean flow flows out through the filter element. The liquid filter element cleans the contaminated liquid (including oil, water, etc.) to the state required for production and life, that is, to achieve a certain degree of cleanliness.