When you hear the word "drying", you might think of clothes or food. But can you imagine that the core power equipment - transformers, which weigh hundreds or even thousands of tons and are of considerable value, also need to undergo a thorough "drying"?
This is no joke. For transformers, internal moisture is the "number one killer" of their insulation performance. Once exposed to moisture, it may not only affect efficiency but also cause internal short circuits, breakdowns, and even lead to serious accidents such as explosions. Therefore, the drying treatment of transformers is a crucial lifeline in their installation, inspection and maintenance processes.
Why are transformers afraid of "moisture"?
The "heart" of a transformer is its internal insulation system, which includes insulating paper and insulating oil. They jointly shoulder the important responsibility of isolating high voltages. However, these insulating materials are inherently hygroscopic.
Decreased insulation strength: Moisture can significantly reduce the dielectric strength of insulating materials, making them prone to breakdown under high voltage.
Accelerated aging: The combined effect of moisture and heat will accelerate the aging and decomposition of insulating paper fibers, shortening the service life of transformers.
Gas generation: After getting damp, under the influence of an electric field, hydrogen and other fault characteristic gases will be produced, which affect the oil chromatographic analysis and judgment and mask the true fault.
Therefore, "drying" a transformer is essentially a "battle to expel" moisture and a necessary measure to restore its healthy condition.
A Comprehensive Reveal of the entire Process of Transformer "drying"
Our professional drying process is not merely about roasting with fire; it is a scientific and rigorous systematic project. It is mainly divided into two major sections: body drying and insulating oil drying.
1. Body drying: Giving the transformer core and coils a "sauna"
When the transformer hoist cover is exposed to the air during maintenance or transportation, the body of the transformer must be dried. At present, the most mainstream and efficient method is the "hot oil spray + vacuum drying" method, which can be regarded as a luxurious "hot oil sauna".
Preparations: Place the main body of the transformer into a dedicated vacuum tank and connect all the heating, vacuuming and measurement pipelines.
Preheating stage: Start the heating system to gently heat the transformer body, making the internal moisture become active and evaporate.
Hot oil spray (sauna core) : Dry and clean hot transformer oil (usually controlled at 80-90℃) is evenly sprayed on all parts of the transformer body through carefully designed nozzles. This is like giving a transformer a refreshing "hot bath" with hot oil, with heat being transferred from the outside to the inside and from shallow to deep.
High vacuum dehydration (deep dehumidification) : While the spray heating is in progress, start a high-power vacuum pump to create a high vacuum state inside the tank. According to physical principles, the boiling point of water in a vacuum environment will drop sharply. At this point, the moisture deeply hidden in the gaps of the insulating material will rapidly boil and vaporize even at relatively low temperatures, and be forcefully extracted by the vacuum pump.
Cycle monitoring and endpoint determination: Throughout the entire process, the vacuum degree of the environment, the temperature of the vessel body, and the moisture content discharged will be continuously monitored. Only when the amount of water discharged per unit time is lower than the strict standard and the vacuum degree remains stable can it be marked that the drying process has been successfully completed.
Ii. Insulating Oil Purification: Rejuvenating the "blood" of transformers
Transformer oil is also afraid of moisture. We use advanced vacuum oil purifiers to synchronously process insulating oil.
When the oil passes through the oil filter, it will undergo high-precision filtration to remove solid particle impurities.
Subsequently, it enters the vacuum degassing tank. Under high-temperature and high-vacuum conditions, the dissolved water and gases in the oil are rapidly extracted and removed.
The treated oil is clean and dry, and all indicators (such as pressure resistance, slight moisture content, and dielectric loss) have been restored to the standards of new oil.
Finally, the dried and qualified transformer body is recombined with the purified insulating oil in a vacuum environment, and a "fully revived" transformer is ready to go.
Choose us and we will safeguard your transformer
The drying treatment of transformers is a technology-intensive task that demands extremely high standards from equipment, processes and experience. Improper operation not only fails to remove moisture but may also cause secondary damage to the equipment.
We have:
Advanced drying equipment: large vacuum tanks, high-speed vacuum pumps, and high-efficiency hot oil spray systems.
Professional technical team: Experienced engineers monitor the entire process and precisely control every drying step.
Strict quality standards: Strictly adhere to international and national standards to ensure that the drying effect is 100% up to standard.
Don't let dampness become a "time bomb" for your power system. Whether it is the installation of a new transformer or the maintenance and repair of an old one, professional drying treatment is an indispensable and crucial step.