How to solve the problem of transformer leakage oil

[Students' Question] How to solve the transformer leakage problem?

[Solution] How to address transformer oil leakage effectively

Transformer oil leakage is a common issue that can lead to serious operational problems and safety hazards. To tackle this, it's important to identify the root cause and apply appropriate solutions. Here are some effective methods:

1. Choose high-quality sealing materials. When repairing or maintaining transformers, it’s essential to use seals that are resistant to high temperatures and oil. Nitrile rubber is widely used in the industry due to its good oil resistance. The performance of nitrile rubber depends on the acrylonitrile content — higher acrylonitrile means better oil resistance and hardness. A Shore hardness between 70 and 80 is typically recommended. Before installation, perform oil resistance tests by soaking the gasket in hot oil at 120°C for 168 hours. Check for weight, volume, and hardness changes. If minimal deformation occurs, it meets the standard.

2. Use a high-quality butterfly valve. Opt for a vacuum eccentric butterfly valve, such as the ZF80 model. This type of valve offers improved mechanical strength and surface finish compared to standard valves. It also features a double-seal design at the flange interface, significantly reducing the risk of leaks.

3. Apply welding for small holes and cracks. For pores, sand holes, or cracks in the casting, electric welding can be an effective solution. First, locate the leakage point. If it's small, directly weld it. For larger leaks, fill the area with asbestos rope or metal packing first, then apply a layer of surfacing material before using a small welding rod for fast arc welding under high current.

4. Follow a proper seal replacement process. Before replacing any seals, clean the flange surfaces thoroughly to remove dust, rust, and debris. Apply a suitable sealant, such as 609 polymer liquid sealant, on both sides of the gasket. After the solvent evaporates and the sealant dries, tighten the flange and screws evenly to ensure a secure fit.

5. Improve installation techniques. Improper installation can cause misalignment and leaks. If the flange is uneven or deformed, correct the alignment if possible. Otherwise, cut and reweld the flange. Ensure the mating surfaces are parallel. During installation, compress the gasket by about one-third of its thickness to maintain a tight seal.

6. Use rapid sealing glue sticks for minor leaks. For small leaks, especially in radiators where traditional plugging isn’t feasible, sealing glue sticks can be an efficient solution. Clean the area thoroughly, removing all oil, paint, and oxide. Adjust the glue ratio according to instructions and apply it until the leak stops completely.

These methods have been tested and applied by trainees during practical work. They are practical and effective for real-world scenarios. If you have any questions or need further clarification, feel free to discuss and improve upon them. Always prioritize safety and follow manufacturer guidelines when performing maintenance on electrical equipment.