Insulating Oil Filtration: Equipment Types and Uses

Insulating Oil Filtration Equipment: Quick Selection Guide

Insulating oil filtration is crucial for maintaining the dielectric strength and safe operation of transformers and high-voltage equipment. Equipment selection depends on the type of contamination, treatment objectives, and site conditions.

Main Types of Insulating Oil Filtration Equipment

Vacuum Oil Purifier

Removes moisture, dissolved gases, and particulate matter under vacuum conditions through heating and fine filtration (1-5 μm).

Best suited for comprehensive purification and on-site transformer oil treatment.

Plate and Frame Filter Press

Uses filter paper to remove coarse solid particles and free water.

Low cost, only suitable for preliminary filtration.

Centrifugal Oil Purifier

Separates free water and heavy particles using centrifugal force; no consumables required.

It can be used as a pre-treatment device, but it is not suitable for removing dissolved moisture.

Adsorption Oil Purifier

Uses silica gel or molecular sieves to remove acids and oxidation products.

Used in conjunction with a vacuum system for oil regeneration.

How to Choose Insulating Oil Filtration Equipment

Water and gas contamination: Vacuum oil purifier

High solid particle or free water content: Centrifugal or plate and frame pre-filter

Aged oil (high acid value): Vacuum + adsorption system

Large transformers: High-flow equipment (≥6000 liters/hour)

Emergency or on-site use: Mobile vacuum oil purifier

The treated oil should comply with GB/T 7595 and IEC 60422 standards.

Recommended Configurations

Routine maintenance: Plate and frame + vacuum oil purifier

Severe contamination: High-efficiency vacuum oil purifier

Oil regeneration: Vacuum oil purifier + adsorption system

On-site emergencies: Mobile integrated system

Key Takeaway

For most applications, a vacuum insulating oil purifier (optionally combined with an adsorption system) provides the most effective and compliant solution.