14/09/2026
What does a transformer radiator actually do?
When an oil-immersed transformer is operating, losses from the windings and core generate heat. The transformer oil absorbs this heat and carries it away from the active part.
Hot oil rises and enters the transformer radiator through the upper connection. It then flows through the radiator elements, where heat is transferred through the steel surfaces to the surrounding air. As the oil cools, it returns to the lower part of the transformer tank.
This circulation helps:
• Control top-oil and winding temperature rise
• Protect transformer oil and cellulose insulation
• Support stable transformer operation
• Extend the service life of temperature-sensitive components
In an ONAN cooling system, both oil and air circulate naturally. In an ONAF system, fans increase airflow across the radiator surfaces to improve heat dissipation.
A power transformer radiator may look simple, but its performance depends on accurate engineering and manufacturing. Radiator dimensions, heat-transfer area, panel spacing, fl**ge centre distance, weld integrity and internal cleanliness all matter.
At Nantong Zhihe Electric, transformer radiators are manufactured according to approved customer drawings. Our capabilities include:
• 7 automatic radiator welding lines
• 100% leakage testing
• Dimensional and fl**ge inspection
• C3–C5 coating systems
• Hot-dip galvanized radiator options
• OEM and ODM production
Need custom transformer radiators for a new transformer project or replacement requirement? Send us your drawing, quantity, coating specification and required delivery date for review.
