Transformer Oil Dehydration Machine

This transformer oil dehydration machine is especially suitable for treating new and old transformer oil, which contains moisture, gas, particles, impurities, and acidic substances. The double-stage transformer oil dehydration plant serves to improve the properties of insulation oil. It eliminates the acid nature, over moisture, traces of water, dissolved gases, and particulate matter from the insulation il effectively and rapidly.

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The Danger of Moisture in Transformer Oil

Moisture in transformer oil leads to a number of undesirable consequences:

  • Intensive aging of insulating paper.
  • Decreases dielectric strength and partial discharge stability.
  • Accelerates the oxidation of transformer oil.
  • Increased carbon formation by electric arcing.
  • Increased corrosion of transformer metal parts.
  • The fluidity of the oil is reduced at higher temperatures.

The above problems can be solved by the transformer oil dehydration machine.

The Form of Moisture in Transformer Oil

In transformer oil, water mainly exists in three forms: dissolved water, suspended water, and sedimentary water.

Oil temperature has a great influence on the existence of moisture in transformer oil. When the oil temperature is high, the water in the oil is mainly dissolved water. If the water reaches the saturated solubility in the oil, it will become supersaturated due to the drop of the oil temperature and form extremely tiny water droplets suspended in the oil and become suspended water. When there is too much-suspended water, it will aggregate into large water droplets and separate from the oil, and deposit on the bottom of the oil to form sedimentary water.

Where does the Moisture in the Transformer Oil Come from?

  • Petroleum products themselves have a certain degree of water absorption and can absorb and dissolve a part of the water from the atmosphere.
  • During the process of packaging, transportation, and storage, transformer oil may enter moisture if it is not kept properly.

What are the Adverse Effects of Moisture on the Electrical Properties of Insulating Oil?

  • Moisture has great harm to the electrical properties and physical and chemical properties of the insulating medium. Moisture reduces the breakdown voltage of transformer oil. It is reported that when the water content in the oil is 0.01%, the breakdown voltage is about 15KV, and when the water content is increased to 0.03%, the breakdown voltage drops to about 6KV. At the same time, moisture also has a significant effect on the dielectric loss factor. When the water content in the oil is 0.03%, the dielectric loss factor is 1*10-2, and when the water content increases by 15 times, that is, 0.10%, the dielectric loss factor increases to 2.1*10-2.
  • Moisture will promote the corrosive effect of organic acids on metals such as copper and iron. The resulting saponification will deteriorate the oil’s dielectric loss factor, increase the oil’s moisture absorption, and accelerate the oxidation of the oil.

Machine Control of Transformer Oil Dehydration Plant

  1. This machine has temperature control, the temperature can be adjusted at request.
  2. This machine uses a photoelectric control device to automatically eliminate foam.
  3. This machine has a high oil level, and a middle oi level to automatically control the oil level.
  4. This machine adopts an over-pressure alarm device, it alarms when oil discharge pressure ≥0.5MPa
  5. This machine has a protection device for overheating, and the heater is not damaged when the oil supply is reduced or interrupted.
  6. Heaters can be divided into multiple groups
  7. This machine has a frequency converter, the flow rate can be adjusted by frequency converter or oil return valve

Technical data of Transformer Oil Dehydration Machine

Item ParameterModel / UnitZJA1.8ZJA3ZJA6ZJA9ZJA12ZJA18
Technical ParameterFlow rateL/H18003000600090001200018000
Temperature range45-65
50Hz    380V3-Phase
(or as requested)
Total powerKW163670100150200
Inlet/outlet diameterDN20/2025/2532/3240/4050/5065/65
Oil Treatment IndexBreakdown voltageKV≥70 
(Spherical electrodes)
Water contentppm≤5
Gas content%≤0.3
Filtering accuracymicron1

The machine size, the weight will change slightly due to different configurations.

Performance of Transformer Oil Dehydration Plant

PerformanceSpecification ( after 3 pass )Initial Oil index
Moisture4±2 ppm 50 ppm
Breakdown Voltage≥75 kV 30kV   
Gas Content≤ 0.10 %v/v12%
Particle filter efficiency99.5% of over 1um/

Customized Design of Transformer Oil Dehydration Machine

No.ComponentsOptions for your selectionEconomy designAdvanced designLuxury design
1Machine typeA.Mobile  B. Skid  C. Trailer mounted  D. Others, please specify______
Your choice:  B    
As you likeAs you likeAs you like
(door and roof)
A. Open style   B. Metal  C. Stainless steel   D. Other please specify__
Your choice: _____
As you likeAs you likeAs you like
3Vacuum pumpA.Chinese brand  B. European brand (LEYBOLD, BUSCH,ATLAS) C.Other please specify_____
Your choice: _____
4Roots pumpA. Chinese brand  B. European brand (LEYBOLD, BUSCH,ATLAS) 
C.Other please specify_____ 
Your choice: _____
5Oil inlet pumpA. Gear pump -Chinese brand  B. Gear pump-European brand
C. Centrifugal pump- European brand  D. None
Your choice:  _____
ADB or  C
6Oil outlet pumpA. Gear pump -Chinese brand  B. Gear pump-European brand
C. Centrifugal pump- European brand
Your choice: _____
AAB or C
7Electric elementsA. CHINT  B. Schneider or ABB  C. Other please specify _____
Your choice: _____       
8InstrumentsA. Digital vacuum meter + temperature controller ( Chinese brand )
B. SIMENS PLC + Digital vacuum meter and temperature controller (Chinese brand)
C. SIMENS PLC and touch screen + INFOCON vacuum sensor and JUMO  temperature sensor (International brand)
Your choice: _____
AA or BC
9Other optional componentsA. Flow meter  B. Inline Water sensor (European brand)  C. Inline gas analyzer  (European brand)  D. Inline particle counter (European brand)N/AAs you likeAs you like
  • All Chinese components are qualified from famous brands which we already used for many years.
  • YUNENG can add more functions or components according to the specific requirements of customers, and carry out product customization services.

In addition, YUNENG also manufactures and sells dry air generators, lubricating oil purifiers, transformer vacuuming systems and more.

Learn the Truth About Transformer Oil Dehydration

The Truth About Transformer Oil Dehydration Is About To Be Revealed

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Adverse effects of moisture on transformer oil 1. Moisture significantly impacts the physical, chemical, and electrical properties of transformer oil. Moisture will reduce the breakdown voltage of the oil. According to reports, the breakdown voltage is about 15kV when the water content in the oil is 0.01%. When the water content was increased to 0.03%, the breakdown voltage dropped to about 6kV. Moisture will affect the dielectric loss factor. As moisture increases, so does the dielectric loss factor. When the water content in the oil is 0.02%, the dielectric loss factor is 1×10-6. When the water content increases to 0.1%,…
Read More The Truth About Transformer Oil Dehydration Is About To Be Revealed