1.The transformer core adopts a six-step joint structure with fully mitered, hole-free, oblique joints, and continuous upper and lower yokes for enhanced mechanical integrity. 

2. Coils are wound using vertical winding machines with pneumatic tensioning devices. The raw coils undergo kerosene vapor-phase drying for thorough moisture removal. After drying, they are pressed using a 200-ton hydraulic press to ensure consistent axial height. 

3.Coil assembly is carried out in a purified transformer body assembly area. Prior to installation, the vertical alignment of the core limbs is measured using an infrared level instrument to ensure concentric alignment between the coil and the core. 

4.The transformer tank adopts a flat-top design. Both the top and bottom plates are cut from whole steel sheets. The tank is preassembled as a complete unit, tested for leaks, and then subjected to overall sandblasting. The rust removal grade reaches Sa2.5 or higher. 

5.The conservator is designed using three-dimensional finite element strength analysis and 3D solid modeling in Pro/ENGINEER. Advanced domestic automatic submerged arc welding is applied during fabrication to ensure oil-tight weld seams without leakage.