Oil-Immersed Transformers

Home / Products / Oil-Immersed Transformers

S11/S13/S20 series distribution and power transformers from 30 kVA to 31.5 MVA, up to 35 kV, with ONAN cooling and fully sealed corrugated tanks.

Oil-Immersed Transformer Manufacturer in China

Our oil-immersed transformers use high-permeability cold-rolled silicon steel cores and oxygen-free copper windings to cut no-load losses by up to 30% compared with older S9 designs. The fully sealed corrugated tank eliminates the oil conservator, preventing moisture ingress and making the transformer maintenance-free for its 25-year design life.

Every unit is routine-tested to IEC 60076 — ratio, winding resistance, applied and induced voltage, no-load and load loss, and insulation oil BDV — with a signed test report shipped alongside the goods. Hermetically sealed, conservator-type and on-load tap changer (OLTC) versions are all available, and we regularly build for 50 °C ambient, 1000 m+ altitude and coastal anti-corrosion environments.

Need a oil-immersed transformers for your project?

Send your specs — we reply with pricing and lead time within 12 hours.