Cleaning a transformer tank primarily involves a combination of mechanical and chemical cleaning methods. The core objective is to remove sludge, rust, and dirt while ensuring operational safety. The following are the specific steps and precautions:
Basic Cleaning Methods
Preliminary Cleaning: Use a scraper and wire brush to remove sludge and rust from the tank surface, especially areas prone to dirt accumulation such as the bottom and heat sinks.
Alkaline Washing Treatment: Immerse the tank in a heated 2%~5% sodium hydroxide solution for several hours to saponify and decompose the oil. Then rinse thoroughly with clean water.
Alternatively, use a heated trisodium phosphate solution for scrubbing, followed by rinsing with clean water.
Deep Cleaning (During Overhaul):After removing the transformer, flush the inside of the tank with qualified transformer oil to ensure no residual impurities remain.
For stubborn oil stains, soak in a mixed solution of sodium carbonate and sodium hydroxide (80~100℃) for about 1 hour. The solution can be reused dozens of times after cleaning.
Cleaning of Accessories and Special Parts
Transformer Bushings: Clean oil stains with alcohol, then wipe clean with a white cloth.
Core Oil Channels: Gently wipe with a lint-free soft brush, then flush each channel with qualified transformer oil at a pressure ≤0.2MPa to ensure unobstructed flow.
Winding Sludge: First, manually peel it off, then flush with a strong oil flow to avoid damaging the insulation layer.
