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About Us
Jiangsu Dingxin Electric Co., Ltd.
Jiangsu Dingxin Electric Co., Ltd. is located in the Industrial Park of Haian Development Zone, a development zone in Jiangsu Province. It is a high-tech enterprise in Jiangsu Province specializing in the production of power equipment, with an annual production capacity of 50 million KVA. It mainly produces 110KV, 220KV and 500KV ultra-high voltage transformers, various dry-type transformers, oil-immersed transformers, amorphous alloy transformers, wind and solar energy storage transformers, prefabricated substations and reactors of various specifications with voltage levels of 35KV and below. , electric furnace transformer, rectifier transformer, mining transformer, split transformer, phase shift transformer and other special transformer. As China OEM/ODM Oil Immersed Transformer Manufacturers and Custom Oil Immersed Transformer Factory, companies have successively passed IS09001, ISO14001, ISO45001, ISO19011 system certification. Among the customers we cooperate with are many urban and rural power grids, as well as petrochemical, metallurgical, textile enterprises, mines, ports, residential communities, etc. We have long-term cooperation with many well-known companies, and we are also qualified suppliers for many listed companies in the electrical industry. Product sales cover the national market and are exported to Europe, the United States, Australia, Indonesia, Russia, Africa, Vietnam and other countries.
Certificate Of Honor
  • Business Licence
  • S22-M-250/10-Nx1 And Energy Efficiency Report
  • SCB18-800/10-NX1 And Energy Efficiency Report
  • SCB18-500/10-NX1 And Energy Efficiency Report
  • SCB18-2500/10-NX1 And Energy Efficiency Report
  • S13-M-1000/10KV Type Test Report
  • S13-M-1000/20KV Type Test Report
  • S13-M.RL-630/10KV Type Test Report
Industry knowledge
What are the main components of an oil-immersed transformer?
The main components of an oil-immersed transformer are as follows:
The core is typically made of laminated steel and provides a path for the magnetic flux. It enhances the efficiency of energy transfer between the primary and secondary windings.
Transformers have two sets of windings: primary and secondary. The primary winding is connected to the input voltage, while the secondary winding is connected to the output circuit. These windings are usually made of copper or aluminum.
Insulating Material:
Insulation materials are used to separate and insulate the conductive components, such as the windings and core. This is crucial for preventing electrical breakdown and ensuring the safe operation of the transformer.
Oil serves as both a cooling medium and an insulating material in oil-immersed transformer  . It helps dissipate heat generated during operation and provides additional insulation. The oil also acts as a medium for extinguishing arcs in case of a fault.
The tank houses the core, windings, and oil. Typically made of steel, it is sealed to prevent the entry of moisture and contaminants. The tank provides mechanical support and protection for the transformer components.
Buchholz Relay:
The Buchholz relay is a protection device installed in the oil circuit. It detects and responds to internal faults, such as overheating or the presence of gas generated by a fault. The relay can initiate an alarm or trip the transformer to prevent further damage.
Conservator Tank:
The conservator tank is an expansion tank connected to the main tank. It accommodates changes in oil volume due to temperature variations, helping to maintain a stable internal pressure and preventing the entry of moisture.
Tap Changer:
Some transformers are equipped with tap changers, allowing the adjustment of the turns ratio. This feature enables voltage regulation, ensuring a consistent voltage level in the secondary winding under varying load conditions.
The breather is a device attached to the conservator tank, preventing moisture from entering the transformer. It typically contains desiccants to absorb moisture from the air drawn into the transformer during oil expansion and contraction.
Pressure Relief Device:
This device is designed to release excess pressure that may build up inside the transformer during abnormal conditions. It helps prevent damage to the transformer and the tank.

How does the oil serve as a cooling medium in the oil-immersed transformer?
Oil serves as a cooling medium in oil-immersed transformer   through a combination of conduction, convection, and radiation. Here's a breakdown of how this cooling process occurs:
Heat Generation:
During the normal operation of a transformer, electrical energy losses occur due to the resistance of the conductors in the windings and the magnetic properties of the core. These losses manifest as heat.
The heat generated in the windings and the core is conducted to the surrounding insulating oil. Transformers are designed with materials that have good thermal conductivity to facilitate efficient heat transfer.
Natural convection is a significant mechanism for cooling in oil-immersed transformers. As the oil absorbs heat, it becomes less dense and rises, creating a natural circulation. The heated oil moves upward, and cooler, denser oil from the upper portions of the transformer flows downward to replace it. This convective flow helps distribute heat within the transformer.
Forced Convection:
In larger transformers or those subjected to heavy loads, natural convection may not be sufficient. Forced convection is achieved by using cooling fans. These fans are strategically placed within the transformer to enhance the circulation of oil. They are often controlled by temperature sensors to activate when needed.
Cooling Surfaces:
The exterior surfaces of the transformer tank act as cooling surfaces. Heat is transferred from the oil to the tank, and from there, it is radiated into the surrounding environment. Some transformers have additional cooling structures, such as radiators or fins, attached to the tank to increase the surface area for better heat dissipation.
Conservator Tank:
Many oil-immersed transformer   include a conservator tank connected to the main tank. The conservator tank provides space for the expansion and contraction of the oil as its temperature changes. This feature helps maintain a stable internal pressure and prevents the entry of moisture and air into the transformer, ensuring efficient cooling.
Heat is also dissipated through radiation from the external surfaces of the transformer tank. This is particularly relevant when the transformer operates at elevated temperatures, and radiation becomes a more significant factor in the overall cooling process.