The transformer core is the main magnetic circuit of a transformer. Its material quality, cutting accuracy, lamination structure, and assembly precision directly affect no-load loss, excitation current, noise, temperature rise, and long-term operating stability.
Using high-grade CRGO electrical steel alone does not guarantee good transformer performance. Excessive burrs, coating damage, dimensional deviation, uneven stacking, or incorrect step-lap joints can still increase core loss and create local overheating.
At Chenfan Electric, transformer core burr height is controlled below 0.02 mm. Proper burr control helps protect the insulation coating between laminations and reduces the risk of interlaminar short circuits, circulating currents, and additional no-load loss.
The stacking factor is controlled above 97%, depending on the material grade, thickness, coating, and core design. A stable stacking factor improves magnetic circuit consistency and helps maintain accurate core dimensions.
Step-lap joint accuracy is another critical factor. Properly designed and manufactured step-lap joints improve magnetic flux distribution at the joint area and help reduce excitation current, vibration, noise, and local magnetic saturation.
Transformer core quality also depends on dimensional accuracy. Limb width, yoke width, window dimensions, stack thickness, joint alignment, diagonal dimensions, and total core weight must all comply with the approved drawing.
For large transformer cores, lifting, clamping, packing, and transportation must also be carefully controlled. Improper handling can create mechanical stress, restrict magnetic domain movement, and negatively affect final no-load performance.
Chenfan Electric manufactures CRGO transformer cores for oil-immersed and dry-type transformers according to customer drawings and technical requirements.
Our production focus includes:
- Burr height below 0.02 mm
- Stacking factor above 97%
- Accurate step-lap joints
- Stable dimensional tolerances
- Controlled lamination sequence
- Protection against deformation during transportation
A high-quality transformer core is not simply a steel component. It is the foundation of transformer efficiency, noise control, thermal performance, and long-term reliability.