Hydraulic oil filter filter accuracy selection

The selection of the filtration accuracy of the hydraulic oil filter is crucial and directly affects the cleanliness of the hydraulic system and the operating efficiency of the equipment. The following are key factors and suggestions to consider when selecting the filtration accuracy:

1. Cleanliness requirements of the hydraulic system

The cleanliness of the hydraulic system is usually defined by the ISO 4406 standard, and the selection of the filtration accuracy should meet the system's requirements for oil cleanliness. For example:

- High-precision systems (such as servo valves, proportional valve systems): cleanliness is required to reach ISO 14/12 or higher, and the filtration accuracy is usually 1-5 microns (μm).

- Medium-precision systems (such as ordinary hydraulic systems): cleanliness is required to reach ISO 16/14 or higher, and the filtration accuracy is usually 5-10 microns (μm).

- Low-precision systems (such as coarse filtration systems): filtration accuracy can be 10-25 microns (μm).

2. Sensitivity of hydraulic components

Different hydraulic components have different requirements for oil cleanliness:

- Servo valves, proportional valves: very sensitive to contamination, it is recommended to choose a filtration accuracy of 1-3 microns (μm).

- Ordinary hydraulic valves, pumps, motors: It is recommended to choose a filtration accuracy of 5-10 microns (μm).

- Hydraulic cylinders, piping systems: It is recommended to choose a filtration accuracy of 10-25 microns (μm).

3. Degree of contamination of hydraulic oil

- New oil or slightly contaminated oil: You can choose a higher filtration accuracy (such as 5-10 microns).

- Severely contaminated oil: It is recommended to perform coarse filtration (such as 25 microns) first, and then fine filtration (such as 5 microns) to extend the life of the filter element.

4. Types of oil filters

- Plate and frame oil filter: The filtration accuracy is low, usually 10-25 microns, suitable for coarse filtration.

- Vacuum oil filter: The filtration accuracy is high, usually 1-5 microns, suitable for fine filtration.

- Centrifugal oil filter: The filtration accuracy is low, usually 10-20 microns, suitable for removing moisture and larger particles.

5. Operating environment

- Highly polluted environments: such as mines, construction sites, etc., it is recommended to choose a higher filtration accuracy (such as 5-10 microns) and ｒｅｐｌａｃｅ the filter element regularly.

- Clean environment: such as laboratories and precision equipment workshops, you can choose a filtration accuracy of 1-5 microns.

6. Economy

- The higher the filtration accuracy, the higher the filter element cost and the higher the replacement frequency. Therefore, it is necessary to find a balance between cleanliness requirements and economy.

7. Filter element type

- Surface filter element (such as filter paper, filter cloth): suitable for lower accuracy (10-25 microns).

- Depth filter element (such as glass fiber, sintered metal): suitable for high accuracy (1-10 microns).

Recommended selection

 Precautions

1. Regularly check the cleanliness of the oil: Use a particle counter to detect the degree of oil contamination to ensure that the filtration accuracy meets the requirements.

2. Filter element replacement cycle: Regularly ｒｅｐｌａｃｅ the filter element according to the degree of contamination and the life of the filter element.

3. Multi-stage filtration: For severely contaminated oil, multi-stage filtration can be used (such as coarse filtration first and then fine filtration).

By reasonably selecting the filtration accuracy, the service life of hydraulic system components can be effectively extended and the system operation efficiency can be improved.