Clean air or clean transformer oil – no need to choose only one
To extract air solved in transformer oil during operation, special vacuum degassing plants are used.
As a rule, a standard degassing unit consists of two metal tanks. Vacuum pump evacuates air from the tanks. Sprayers are installed in the top of the tanks to spread the oil uniformly across the internal space of the tanks. The process continues until volumetric gas content is below 0.04%. From the degasser the oil flows to the transformer tank, where the same vacuum pressure is maintained.
In recent years comprehensive oil regeneration plants have been coming into use. They include dehydration, degassing, filtration and lightening of transformer used transformer oil.
The reason for this is not only the savings of buying one plant instead of three, but also increased transformer efficiency and extended lifetime.
Transformer oil is almost constantly subjected to high temperatures, serving as a coolant; the amount of gases in the oil increases over time. Besides, transformer oil adsorbs air which may enter the transformer from the outside.
The use of complete oil regeneration systems of CMM type reduces the costs of equipment servicing and repairs. One mobile degassing, purification and regeneration system can serve multiple transformers; it can be transported around the site and from site to site. No additional adjustment is required when switching treated transformers.
With the help of these degassers and regeneration plants, it is also possible to remove sediment and other contaminants from solid insulation, which are difficult to remove and which continue to adversely affect the oil even if new oil is filled into an old transformer. The method increases both oil and transformer service life.
Oil, circulated from the transformer into the regeneration plant, passes several stages. Unlike regular degassing or filtration plants, in this case the oil goes back to the transformer completely restored. The differences from new oil are slight.
CMM complete oil regeneration systems are a reasonable replacement for regular degassing machines. The demands and capacities of industrial facilities ever increase. Therefore rational investment into one plant instead of three or more, and servicing several transformers to the degree where the oil in the transformers becomes as good as new, is a sound economical choice.