Transformer Air-Cooler

Product Overview

Transformer forced oil-air coolers (hereinafter referred to as “air coolers”) are critical auxiliary cooling devices for large oil-immersed power transformers, reactors, and other power equipment. When the top oil temperature of the transformer reaches a set value, the air cooler automatically activates. Through forced oil circulation, the hot oil inside the transformer is directed into the cooler body, where forced air blowing rapidly dissipates heat to the surrounding atmosphere. The cooled oil returns to the transformer tank, forming a closed-loop cooling circuit that effectively controls transformer temperature rise and ensures safe, stable equipment operation.

Kaiyang air coolers are widely used in oil-immersed transformer cooling systems for power plants, substations, renewable energy stations (PV and wind), industrial and mining enterprises, and rail transit. The company initiated R&D in 2023 and achieved mass production of transformer forced oil-air coolers in 2024, delivering efficient, constant-temperature air-cooling solutions for global power systems with solid manufacturing expertise and innovative technology.

 Production & Manufacturing Capabilities

The production center is equipped with over 300 advanced processing and inspection systems, adhering to full-lifecycle quality control to meet stringent global customer demands for high-precision fabrication and scalable delivery of core components.

 Core Equipment Overview

Process	Equipment
Precision Cutting	6kW large-format laser plate cutters ×2
CNC Forming	4m 250-ton CNC linkage press brakes ×2, CNC tube end cutting machine ×1
Welding Cluster	Plate-and-tube welding machines ×6, spot welders ×2, Panasonic inverter MIG welders ×10, Panasonic inverter TIG welders ×8
Fluid Purification	Vacuum and particulate oil filters ×4, flushing units ×2
Performance Testing	Industrial leak test tanks ×3, winding machines ×2
Sealing Inspection	Gantry-type spray leak test station ×1

 Integrated Manufacturing System

Kaiyang Electric operates automated shot blasting and coating lines, with a complete production chain from raw material cutting, precision welding, systematic flushing, to final pressure testing – ensuring high-standard turnkey delivery.

 Core Technical Advantages

 1. Large-Scale CNC Linkage Bending Machine

Performs high-precision bending of extra-long and thick plates used for cooler main frames and fan housings. Bending angles are precisely controlled, and long edges can be formed in a single pass without welding, effectively ensuring overall structural strength and stability.

 2. Plate-and-Tube Welding Machine

Used for precision welding between cooler plates and heat exchange tubes. Welds are sealed firmly without leakage, ensuring reliable heat exchange performance and stable media flow.

 3. High-Precision CNC Camless Wire Winding Machine

Employs servo motors to precisely control robotic arm trajectories, offering easy operation and accurate positioning. Ensures perfect fit between turbulence wires and the inner walls of steel-aluminum composite tubes, significantly enhancing heat dissipation efficiency and ensuring transformer stable operation.

 4. Oil Filtration and Flushing Equipment

– Two-Stage Vacuum Oil Purifier: Deep purification of transformer oil, efficiently removing impurities and harmful gases, achieving oil quality indicators superior to industry standards.

– Particulate Oil Filter: Specially reduces oil particle counts, ensuring particulate levels meet and exceed specification requirements.

– High-Flow Flushing System: Equipped with a 400m³/h high-flow oil pump for comprehensive internal cavity flushing, ensuring critical parameters (dielectric loss, dissolved gas analysis, particle count, moisture content) meet and exceed specification requirements.

 Product Advantages

High-Efficiency Heat Dissipation

Dual heat exchange mechanism – forced oil circulation combined with forced air cooling – delivers high thermal efficiency and significant temperature reduction, precisely controlling transformer operating temperature.

Robust Construction

Main frames are formed in a single pass using large-scale CNC linkage bending machines, minimizing weld seams and enhancing overall structural strength and deformation resistance for various demanding operating conditions.

Reliable Quality

Strictly manufactured in compliance with ISO9001, ISO14001, ISO45001, and ISO3834 international standards. Each unit undergoes rigorous leak testing and oil circulation flushing before shipment, ensuring stable media flow without leakage.

Stable Operation

Plate-and-tube welds are firmly sealed; turbulence wires are closely fitted; oil passages are unobstructed and airflow evenly distributed, ensuring consistent heat exchange performance throughout long-term operation.

Flexible Customization

Cooling capacity, structural dimensions, fan configurations, mounting methods, and surface treatments can be customized to suit specific transformer cooling requirements.

 Quality Assurance & Industry Recognition

Kaiyang Electric has accumulated multiple core invention and utility model patents. Products are widely used in national power grid infrastructure, with deep cooperation with industry leaders including China XD Group, TBEA, Shandong Electric, Luneng Group, and Taikai Group. With over 200 power project track records, Kaiyang Electric supports the development of industry benchmark enterprises through core technology.

 Global Project Track Record

Kaiyang Electric’s primary markets span China, Central Asia, Southeast Asia, Africa, Europe, and the Americas. Core clients include members of China Electrical Equipment Group (Shandong Electric Engineering & Equipment Group Co., Ltd., China XD Electric Co., Ltd., Xuji Transformer Co., Ltd.), TBEA Co., Ltd., Taikai Group Co., Ltd., Zhongtian Technology Group Co., Ltd., Jiangsu Huachen Transformer Co., Ltd., and Shandong Luneng Taishan Power Equipment Co., Ltd.

 International Projects (Selected)

Europe

– Russia: Air cooling system for 35kV oil-immersed transformer in Moscow suburban distribution network

– Greece: Transformer air cooling system for Crete Interconnection Project

– Italy: Main transformer air cooler retrofit project for Terna grid substations

Central Asia & Middle East

– Saudi Arabia: Oil-air coolers for ultra-high voltage transformer projects of Saudi Electricity Company

– Uzbekistan: Main transformer oil-air cooling system for 300MW PV station at Navoi Integrated Energy Project

– Oman: Transformer air cooling system for Duqm 500MW PV Power Station

Africa

– Egypt: Forced oil-air coolers for 500kV transformers at South Helwan Power Plant

– South Africa: Air cooling systems for ESKOM energy storage projects and transformer framework agreements

– Ethiopia: 35kV off-grid PV transformer air cooling system for Addis Ababa “Light Up Africa” project

Americas

– Brazil: Large-scale cooling system for UHVDC converter transformers in Belo Monte Phase II project

– United States: Air cooling system for nitrogen-sealed oil-immersed transformer at Texas PV station

 Domestic Key Projects (Selected)

– Zhejiang Huakang Engineering Institute – Hexigten Banner 500kV Substation

– Gaoyou 500kV Substation renovation

– Qinglongshan 220kV switch station upgrade to 500kV substation

– Dangtu 500kV substation reactor renovation

– Ludao 500kV Substation expansion

– State Grid Inner Mongolia Taohemu 500kV Substation

– CRRC Qishuyan Locomotive & Rolling Stock Technology Research Institute – 330kV substation

– Fuzhuang 330kV substation new construction

– State Grid Sichuan Leshan Power Supply – 330kV Leshan Substation No.1 & No.2 main transformer energy efficiency improvement

– State Grid Chongqing Jiulongpo Chenjiaping 500kV substation main transformer expansion

– 2024 Ganzhou North 500kV transmission and transformation project

– Qinghai Haixi Dulan 330kV substation main transformer capacity expansion

– Dagang Oilfield Beidagang 500,000kW PV power generation project – 500kV booster station and transmission line PC general contracting

– Baiyin Jingtai Development New Energy – Jingtai Wufo Township 330kV collector station project

 Customization Services

Kaiyang Electric provides comprehensive customization services, offering flexible adjustments to cooling capacity, structural dimensions, fan configurations, mounting methods, surface treatments, and colors. Minimum Order Quantities (MOQs) vary by customization scope. Please contact our sales team for detailed solutions.

Kaiyang Air Coolers – Pure Cooling at the Core; Surging Power, Unchanging Coolness. Kaiyang Electric is committed to providing efficient, constant-temperature air-cooling solutions for global industrial power systems.