On-Site Purification Treatment Plan for Transformer Vacuum Oil Filtration

1. Project Overview

This on-site purification process targets oil-immersed transformers during operation or maintenance, as prolonged operation often leads to issues such as insulation oil moisture absorption, contamination, aging acidification, and reduced breakdown voltage. To remove moisture, gases, and solid particles from the oil, enhance insulation strength, and ensure the transformer's insulation performance meets standards, a high-vacuum oil purifier is employed for on-site filtration and purification, safeguarding the safe operation of the equipment.

2. Purpose of Processing

Remove free water, dissolved water, air, carbonized impurities, and metal dust from transformer oil; reduce oil acidity, enhance dielectric strength; improve the physicochemical properties of the oil, delay insulation aging; eliminate hidden hazards such as partial discharge, overheating, and insulation degradation caused by oil quality deterioration, ensuring the oil meets the standards for power handover and preventive testing.

3. Preliminary Preparations

Before starting the work, disconnect the high and low voltage power supplies of the transformer, and implement safety measures such as grounding, tagging, and locking. Collect initial oil samples, and record original data including breakdown voltage, water content, particle size, and acid value. Inspect the filter oil machine's pipelines, seals, heating system, and vacuum pump status. Clean up oil stains and debris on-site, arrange fire prevention and dust control measures, and confirm that the ambient temperature and humidity meet the requirements for oil filtration operations.

4. On-site Purification Process Flow

The closed-loop circulating filtration method is employed by connecting the transformer's inlet and outlet ports, activating the vacuum system, and maintaining a vacuum negative pressure state. Initially, low-temperature circulation removes impurities, filtering solid contaminants from the oil. Subsequently, heating is applied to reduce oil viscosity and accelerate water vaporization. The vacuum separator tank is then used to extract moisture and harmful gases. The oil undergoes multi-stage filtration through precision filters, with repeated cycles for purification. The entire process is monitored in real-time for oil temperature, vacuum level, and pressure to prevent localized overheating and oil spraying.

5. Key Points for Operation Control

Strictly control the heating temperature to ensure the oil temperature does not exceed the specified limit, preventing accelerated oil aging. Maintain stable vacuum levels and eliminate air leakage and moisture absorption. Prohibit disassembly or installation of pipelines during filtration, and regularly inspect for filter clogging. Conduct timed sampling and testing during the circulation process until dielectric strength, moisture, and impurity levels meet standards. Outdoor oil filtration operations are prohibited in rainy, high-humidity, or dust-laden weather conditions.

6. Completion Acceptance Standards

After purification, let it stand to degas and take oil samples for testing. The breakdown voltage, moisture content, particle size, and acid value of the insulating oil must all meet national standard requirements; the oil should be clear and transparent, free of suspended matter, moisture, and bubbles. Organize the equipment pipelines, seal the transformer oil ports, and clean the site. Retain pre- and post-contrast test reports for archiving and future reference. Power supply can only be restored after passing the acceptance inspection.

7. Safety Assurance Measures

Workers must be certified and equipped with insulated protective gear. Fire extinguishers and fire blankets should be available on-site, and open flames are strictly prohibited. Equipment must be reliably grounded to prevent static electricity buildup. A dedicated supervisor should monitor the entire operation, and live electrical work is forbidden. Upon completion, inspect the pipelines for leaks or residual debris to ensure the transformer is free of safety hazards.

High Vacuum Transformer Oil Filtration Machine