Coils need careful handling through the drying, pressing, and sizing operations. All coils are dried and oil sprayed using vapor phase drying (VPD) process under isostatic pressure. Isostatic compression stabilizes the actual height during the drying process. Windings are kept compressed until nesting to avoid axial spring-back.
To make sure this process is flawless, we use a home-grown, hi-tech device, winding mushroom. The mushroom ensures that isostatic compression is uniform, and continuous throughout the VPD process. This process is crucial in meeting the design parameters for short circuit.