Core cutting and winding processes (laminated core / wound core) Coil winding:
horizontal winding, vertical winding; continuous winding, helical winding, CTC interleaved winding Insulation assembly and lead assembly Vacuum drying (variable pressure drying, vapor phase drying) Vacuum oil filling (for oil-immersed transformers) Factory acceptance tests:
no-load loss, load loss, partial discharge test, withstand voltage test, induced voltage withstand test