Power Transformer Oil Tank – Corrugated Oil Tank for Oil-Immersed Transformers

The power transformer oil tank is the main enclosure of an oil-immersed transformer, designed to house the magnetic core and windings while being filled with insulating transformer oil. The oil provides both electrical insulation and effective heat dissipation, ensuring stable transformer performance and long service life. High-quality transformer oil tanks are essential for maintaining operational reliability in power distribution and transmission systems.

Function of Power Transformer Oil Tank

The transformer oil tank serves as a protective casing that immerses the transformer core and coils in insulating oil. This oil acts as both a dielectric medium and a cooling agent. During operation, heat generated by the windings is transferred to the oil and dissipated through the tank walls. For large-capacity transformers, separate oil tanks are typically used for the main body and the on-load tap changer. This separation prevents contamination caused by arc generation during tap changer operation, preserving insulation quality and improving system safety.

Corrugated Transformer Oil Tank Structure

The corrugated oil tank for oil-immersed transformers consists of a main tank body and corrugated cooling panels installed on the outer surface. These corrugated plates are manufactured using specialized forming equipment and welded using gas-shielded welding technology to ensure structural integrity and minimize leakage. The long and short corrugated plates are designed with right-angle edges to facilitate welding, improve manufacturing efficiency, and enhance sealing performance.

This structural design offers compact dimensions, improved heat dissipation, reduced oil leakage risk, and an aesthetically clean appearance. The corrugated walls also function as cooling fins, eliminating the need for additional radiators in many applications.

Transformer Oil Tank Types

Corrugated oil tank for distribution transformers such as S9, S11, ZS11, and SHB11 models.

Finned oil tank for power transformers including S11, SZ11, SFZ11 and similar models.

Applicable Transformer Range

Voltage levels: 10kV and 35kV power distribution systems.

Capacity range: 50kVA to 1600kVA oil-immersed transformers.

Cooling and Oil Circulation Principle

The transformer oil tank is connected to an oil conservator through piping. When oil volume decreases, oil flows from the conservator into the tank to maintain proper oil level. When temperature rises during load operation, the oil expands and flows back into the conservator. This circulation maintains stable internal pressure and prevents air ingress.

The corrugated structure enables natural oil convection. As oil temperature increases, heated oil rises while cooler oil descends, forming a continuous circulation loop. This natural convection improves cooling efficiency and enhances transformer reliability without requiring additional cooling equipment.

Transformer Oil Tank Structure Components

Tank rim for structural reinforcement and cover mounting.

Corrugated wall panels for cooling and expansion compensation.

Tank bottom for mechanical support and oil containment.

Power Transformer Oil Tank Features

High mechanical strength steel plate construction.

Excellent sealing performance with low leakage rate.

Corrugated cooling design for improved heat dissipation.

Compact structure with reduced installation space.

Natural oil circulation without external radiators.

Long service life and corrosion resistance.

Customizable design based on transformer rating.

Customization and Ordering Information

Transformer oil tanks can be custom manufactured according to customer drawings. Design optimization is available based on transformer capacity, voltage level, and cooling requirements. Various corrugation depths, steel thicknesses, and anti-corrosion coatings can be selected to meet specific operating environments.

Applications

Oil-immersed distribution transformers.

Power transformers for substations.

Industrial power transformers.

Renewable energy transformer systems.

Utility grid distribution equipment.

The power transformer oil tank plays a critical role in transformer insulation and cooling performance. With corrugated structure design, efficient heat dissipation, and reliable sealing, it ensures stable transformer operation across various voltage levels and capacities. Custom manufacturing options make it suitable for distribution and power transformer applications worldwide.