What are the transformer oil filtration devices?

The transformer oil filter is primarily used to remove moisture, gases, impurities, and particulate matter from oil, thereby restoring or maintaining the insulation performance and chemical stability of the oil. Common transformer oil filter devices include the following categories:

1. Vacuum oil filter (vacuum dehydration and degassing device)

- Principle: Heat the transformer oil in a vacuum environment, evaporate moisture and gas through negative pressure, and filter solid impurities at the same time.

- Function:

- Remove free water and dissolved water (the water content can be reduced to below 10ppm).

- Remove dissolved gases (such as oxygen, nitrogen, etc.).

- Filter mechanical impurities (such as metal particles, fibers, etc.).

- Applicable scenarios: new oil treatment, operating oil regeneration, and oil treatment after transformer maintenance.

2. Pressure oil filter (plate and frame oil filter)

- Principle: Pressurize the oil to pass through the filter paper or filter membrane to absorb moisture and intercept particulate matter.

- Function:

- Remove suspended impurities and a small amount of water.

- Improve the mechanical cleanliness of the oil (such as removing particles ≥5μm).

- Disadvantages: Unable to remove dissolved water and gas, and filter paper needs to be replaced frequently.

- Applicable scenarios: coarse filtration or use with a vacuum oil filter.

3. Centrifugal oil filter

- Principle: Use centrifugal force to separate dense water and impurities in the oil.

- Function:

- Quickly separate free water and solid particles.

- Disadvantages: Limited effect on dissolved water and tiny particles.

- Applicable scenarios: Preliminary treatment of oil with high water content.

4. Adsorption oil filter (such as silica gel, molecular sieve oil filter)

- Principle: Remove water and acidic substances through adsorbents (silica gel, activated alumina, molecular sieves, etc.).

- Function:

- Deep dehydration (can be reduced to below 5ppm).

Reduce the acid value in the oil to improve its quality.

- Applicable scenarios: Regeneration of aged oil.

5. Electrostatic oil filter

- Principle: Use an electrostatic field to adsorb tiny colloidal particles and carbides in oil.

- Function:

- Remove extremely fine particles (submicron level) and colloidal impurities.

- Applicable scenario: Precision filtration of ultra-high voltage transformer oil.

6. Coalescing and separation oil filter

- Principle: Use coalescing materials to merge tiny water droplets into large water droplets, and then discharge them through the separator.

- Function:

- Efficiently remove water (especially suitable for emulsified water).

- Applicable scenario: Oil with high water content and severe emulsification.

7. Online oil filter (transformer oil online monitoring and filtration system)

- Principle: Integrated sensors and filtration units, real-time monitoring and automatic filtration of water, gas and particles in oil.

- Function:

- Continuously maintain oil quality and extend transformer life.

- Applicable scenario: Long-term operation and maintenance of important transformers.

Selection basis

- Type of oil pollution: water, gas, particles or acidic substances.

- Treatment target: rapid dehydration, deep purification or regeneration.

- Oil volume requirement: small portable or large fixed equipment.

Notes

- Oil quality (such as pressure resistance, dielectric loss, water content, etc.) must be tested before filtration.

- The oil temperature must be controlled during filtration (usually 50~60℃) to avoid oxidation.

- After treatment, the oil quality must be re-checked to see if it meets the standards (such as IEC 60422 or GB/T 7595).

If you need more specific equipment models or technical parameters, please contact me and I will answer you attentively.