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Can the vacuum oil filter filter impurities?

Time:2025-04-02 11:26:41  Reading volume:

A vacuum oil filter can not only remove water and gas efficiently, but also filter solid impurities in oil simultaneously, but the specific impurity removal effect depends on its design configuration (such as whether it integrates a precision filtration system). The following is a detailed description:

Impurity filtration capability of the vacuum oil filter

1. Basic impurity removal function


- Most vacuum oil filters will be equipped with mechanical filters (such as filter elements, filter bags, filter screens) at the oil inlet or outlet to intercept solid particles.


- Typical filtration accuracy: 1~30μm (depending on the filter element grade), which can remove pollutants such as metal chips, dust, and oil sludge.


- Impurity removal rate: up to 99% or more (β value ≥ 200, that is, the number of oil particles after filtration is reduced by 200 times).


2. Multi-stage filtration design


- Primary filtration (coarse filtration): metal mesh or filter bag (20~50μm), to protect the oil pump and heater.


- Fine filtration (main filtration): high-precision filter elements (1~10μm) such as glass fiber and sintered metal, deep purification.

- Optional magnetic filtration: adsorption of ferromagnetic particles (such as iron filings generated by bearing wear).


The coordinated process of impurity filtration and vacuum dehydration

Take a typical vacuum oil filter as an example:

1. Pretreatment (coarse filtration): The oil first passes through the coarse filter to remove large particles (≥50μm) to prevent clogging of subsequent components.

2. Heating and dehydration: After the oil is heated, it enters the vacuum separation chamber, and the water and gas are evaporated and separated.

3. Fine filtration and purification: The dehydrated oil passes through the fine filter element to intercept the residual tiny particles.

4. Output clean oil: The final oil can meet the requirements of low moisture (≤50ppm) and high cleanliness (such as NAS level 6~8) at the same time.

Applicable impurity types and restrictions

| Impurity types | Treatment effects | Precautions |

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

| Metal particles | Efficient removal (especially magnetic particles) | Magnetic filters need to be cleaned regularly |

| Dust/sand | Depends on filter element accuracy (such as 5μm filter element) | High-concentration impurities require pre-coarse filtration |

| Sludge/colloid | Some colloids can be filtered out | Severely oxidized sludge requires adsorption treatment |

| Fiber impurities | Filter screen or filter bag interception | Avoid using fiber filter materials that are easy to shed |

Vacuum oil filter vs. pure mechanical oil filter

| Comparison items | Vacuum oil filter | Pure mechanical oil filter |

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

| Water removal capacity | Can handle free water and dissolved water | Can only remove free water (requires coalescing filter element) |

| Impurity removal capacity | Depends on additional filter element, flexible precision | Focus on particle filtration, higher precision (optional) |

| Operating cost | Higher (energy consumption + vacuum maintenance) | Lower (only filter element replacement) |

| Typical applications | Transformer oil, turbine oil deep purification | Hydraulic oil, gear oil particle control |

User FAQs

Q1: Can the vacuum oil filter remove all impurities?

- No. For submicron particles (<1μm) or colloidal substances, electrostatic adsorption or centrifugal separation is required; for acidic substances, additional adsorbent treatment is required.


Q2: What should I do if the filter element is clogged?

- Monitor the pressure difference before and after the filter element (replacement is required if it exceeds 0.3MPa);

- Pre-filtration or staged treatment is recommended for highly polluted oil.


Q3: Can impurities in fuel be filtered?

- Yes, but you need to use an explosion-proof vacuum oil filter (low fuel flash point) and confirm that the filter material is compatible with the fuel (such as fluororubber seals).

Maintenance recommendations

1. Regularly replace the filter element: replace it every 50~500 hours according to the degree of contamination.


2. Clean the vacuum system: prevent condensed water from corroding the components.


3. Oil sample testing: Regularly test the particle count (ISO 4406) and water content to verify the performance of the equipment.


The vacuum oil filter is an integrated "dehydration + impurity removal" device. By properly configuring the filter element precision, it can simultaneously solve the problems of water, gas and solid pollutants in the oil. It is an ideal choice for scenarios where water purification is the main focus and impurities are supplementary (such as the power industry); if particle control is the core (such as precision hydraulic systems), high-precision mechanical oil filters can be given priority or the combination of the two.

vacuum oil filter filter