What is the maximum temperature of the transformer oil purifier?

Temperature control of transformer oil during filtration is crucial. Excessive temperature may cause oil oxidation, aging or additive decomposition. Specific requirements are as follows:

1. Temperature upper limit requirements

- General standards:

- The maximum temperature does not exceed 65℃ (common range: 50~60℃).

- Some high-precision vacuum oil filters allow a short-term temperature rise to 70℃ (time must be strictly controlled).

- Based on standards:

- IEC 60422: It is recommended that the oil filtration temperature should not exceed 60℃ to avoid thermal degradation of oil quality.

- GB/T 14542-2017 (Transformer Oil Maintenance Guide): Requires that the oil temperature should be ≤65℃ during oil filtration.

2. Risk of excessive temperature

- Oil oxidation: At high temperatures, oil reacts with oxygen to generate acid and sludge, which reduces insulation performance.

- Additive decomposition: Some antioxidants (such as DBPC) may fail at >70℃.

- Uneven evaporation of water: Local overheating may lead to incomplete evaporation of water, affecting the vacuum dehydration effect.

3. Temperature recommendations for different processes

| Filtration process | Recommended temperature range | Description |

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

| Vacuum oil filtration (dehydration and degassing) | 50~60℃ | Optimal balance point: fast evaporation of water, low oxidation risk |

| Pressure oil filtration (particle filtration) | 40~55℃ | Avoid high temperature causing filter element blockage or damage |

| Centrifugal oil filtration | ≤60℃ | High temperature may affect the sealing performance of the centrifuge |

4. Precautions

- Real-time monitoring: The oil filtration equipment should be equipped with a temperature sensor and an over-temperature automatic alarm or shutdown.

- Preheating control: When starting with cold oil, it needs to be heated slowly (heating rate ≤5℃/hour) to avoid local overheating.

- Ambient temperature: In winter, in a low temperature environment, the oil needs to be preheated to ≥20℃ before filtering to prevent viscosity from affecting the flow rate.

5. Special situation handling

- High water content oil: If the water content is seriously exceeded (>50 ppm), the temperature can be temporarily raised to 65℃ to improve dehydration efficiency, but the processing time needs to be shortened.

- Regeneration of old oil: The temperature needs to be carefully controlled (≤60℃) to avoid further polymerization of oxidation products.

The transformer oil filtration temperature should be strictly controlled below 65℃, and the ideal range is 50~60℃. In actual operation, it is necessary to combine the equipment type, oil quality status and standard requirements, and give priority to ensuring the chemical stability of the oil.