The role of lubricating oil vacuum dehydrator

Function of Lubricating Oil Vacuum Dehydrator: Lubricating oil vacuum dehydrator (also called vacuum oil filter) is mainly used to remove water, gas, and impurities in lubricating oil, restore the viscosity, oxidation resistance, cleanliness and other properties of lubricating oil, extend the service life of equipment, and ensure the stable operation of the mechanical system.

Main functions

(1) Removal of water (core function)

- Free water (large water droplets) → through gravity sedimentation or centrifugal separation.

- Emulsified water (oil and water mixed into an emulsion) → through vacuum demulsification + evaporation removal.

- Dissolved water (trace water dissolved in oil) → through high vacuum + heating evaporation removal.

Effect: Reduce the water content of lubricating oil to ≤50ppm (even below 10ppm), prevent oil emulsification and equipment corrosion.

(2) Removal of gas

- Remove air, oxygen, hydrogen, etc. dissolved in oil to prevent cavitation, oxidation, foam and other problems.

Effect: Improve the oil's antioxidant properties and reduce the interference of bubbles on the hydraulic system.

(3) Filter solid impurities

- Remove metal particles, dust, colloid and other pollutants through coarse filtration (20~50μm) + fine filtration (1~5μm).

Effect: Reduce equipment wear, improve lubrication effect, and meet ISO 4406 / NAS 1638 cleanliness standards.

(4) Restore lubricant performance

- Improve viscosity index (VI) and reduce the loss of lubrication performance caused by moisture and impurities.

- Reduce acid value (TAN), delay oil aging, and reduce equipment corrosion risk.

Differences from ordinary oil filters

| Comparison items | Vacuum dehydrator | Ordinary oil filter |

|-----------|--------------|--------------|

| Dehydration capacity | Can remove free water, emulsified water, dissolved water | Can only remove free water |

| Degassing capacity | Can remove dissolved gases (O₂, N₂, etc.) | No degassing function |

| Filtration accuracy | 1~5μm (fine filtration) | Usually above 10μm |

| Applicable oils | Oils with serious water and gas content | Oils with only slight contamination |

| Typical applications | Turbine oil, hydraulic oil, transformer oil | General industrial lubricants |

Precautions for use

1. Control temperature: Heat to 50~70℃ (too high will cause oil oxidation).

2. Vacuum adjustment: Generally -0.085 ~ -0.098 MPa, too low will affect the dehydration effect.

3. Filter element maintenance: Regularly ｒｅｐｌａｃｅ the fine filter element (if the pressure difference is greater than 0.3MPa, it needs to be replaced).

4. Explosion-proof requirements: When handling flammable oils, the equipment must comply with ATEX / IECEx explosion-proof standards.

Lubricating oil vacuum dehydrator can not only remove water, gas and impurities efficiently, but also restore oil performance. It is suitable for industries such as power, petrochemical, and machinery manufacturing. It is key equipment to extend equipment life and reduce maintenance costs.