What are the insulating oil purification equipment?

Insulating oil (such as transformer oil, switch oil, etc.) purification equipment is mainly used to remove moisture, gas, particulate matter and oxidation products in the oil to restore its insulation performance and extend its service life. The following are the classifications and characteristics of common insulating oil purification equipment:

Core equipment classified by function

1. Vacuum oil filter

- Core function:

- Deep dehydration (can be processed to ≤10ppm moisture)

- Degassing (gas content ≤0.1%)

- Filter particles (1-5μm accuracy)

- Applicable oil products: transformer oil, capacitor oil

- Representative models:

- Two-stage vacuum oil filter (ultimate vacuum -0.099MPa)

- Online vacuum oil filter system (with transformer real-time purification)

2. Centrifugal oil filter

- Core function:

- Rapid separation of free water and large particles (≥5μm)

- No need to ｒｅｐｌａｃｅ the filter element, suitable for high-pollution oil pretreatment

- Limitation: Unable to remove dissolved water and tiny particles

3. Coagulation separation oil filter

- Core function:

- Specializes in water removal (50-100ppm)

- Significant effect in treating emulsified oil

- Typical application: Substation maintenance in humid areas

4. Electrostatic adsorption oil filter

- Core functions:

- Remove colloids and oxides (improve dielectric loss factor tanδ)

- Applicable scenarios: regeneration of aged oil

Classification by usage scenario

| Equipment type | Applicable scenarios | Advantages |

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

| Portable | On-site emergency treatment, small substation | Lightweight (<100kg), diesel drive optional |

| Fixed | Large converter station, centralized treatment of oil depot | Large flow (5000L/h), fully automated control |

| Online | Real-time protection of UHV transformers | 24-hour monitoring, automatic start and stop |

Comparison of key performance parameters

| Parameters | Vacuum oil filter | Centrifugal | Coalescing |

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

| Moisture treatment (ppm) | ≤10 | ≥50 | ≤50 |

| Filtration accuracy (μm) | 1-5 | 5-10 | 3-5 |

| Gas content (%) | ≤0.1 | No treatment | No treatment |

| Energy consumption (kW) | 15-30 | 5-10 | 10-20 |

Selection recommendations

1. Pre-treatment of new oil injection → ｓｅｌｅｃｔ vacuum oil filter (to ensure initial cleanliness)

2. Emergency repair of damp oil → Portable coalescing + vacuum combination machine

3. Regeneration of aged oil → Electrostatic adsorption + vacuum multi-stage treatment

4. UHV substation → Online monitoring + automatic filtration system

Reference of international mainstream brands

- Europe: Pall (Germany), C.C.Jensen (Denmark)

- USA: Hy-Pro, Eaton

- China: Chongqing Tongrui, Chongqing SINO-NSH (high cost performance, fast service response)

Maintenance points

- Filter replacement: ｒｅｐｌａｃｅ immediately when pressure difference > 0.15MPa

- Vacuum pump oil: ｒｅｐｌａｃｅ every 500 hours

- Annual calibration: vacuum gauge, moisture sensor accuracy check

Through reasonable selection, insulating oil purification equipment can extend the oil life by 3-5 times and reduce the transformer failure rate by more than 60%. The equipment function needs to be matched according to the oil inspection report (such as dielectric strength, moisture content).