Oil-Immersed Transformers — Direct China Manufacturer XinHuan

Oil-Immersed Series

Oil-Immersed Transformers

Distribution and power transformers built for industrial, utility, and export projects. Stable thermal performance in harsh conditions, from 30 kVA up to 40,000 kVA.

30 kVA – 40,000 kVA

Matched Products

198

Voltage Class
Rated Capacity
IEC 60076 & IEEE C57 Engineering Standard

IEC 60076 Oil-Immersed Distribution & Power Transformers (30 kVA – 40,000 kVA)

XinHuan oil-immersed transformers utilize high-permeability cold-rolled grain-oriented (CRGO) silicon steel cores, electrolytic copper or aluminum conductor windings, and hermetically sealed corrugated tanks to prevent oil oxidation, delivering 30+ years of maintenance-free service.

Hermetically Sealed Tank

Corrugated fin radiators flex under thermal expansion, keeping transformer oil completely isolated from atmospheric air and moisture.

Ultra-Low Loss Step-Lap Core

Multi-stage 45° step-lap miter joint core minimizes magnetic reluctance and excitation current, exceeding IEC EcoDesign Tier 2 mandates.

High BDV Dielectric Oil

High-grade mineral oil or natural ester FR3 with breakdown voltage (BDV) > 50 kV and flashpoint up to 300°C for elevated safety.

100% FAT Routine Testing

Every transformer undergoes full routine testing: winding resistance, ratio, impedance, load/no-load losses, and separate-source AC withstand.

Oil-Immersed Series Matrix

Series Capacity Voltage Key Benefit
S11 Series 30–2500 kVA 11kV, 33kV Proven baseline reliability
S13 Series 50–3150 kVA 11kV, 22kV, 33kV -15% No-load loss vs S11
S20 Series 100–2500 kVA 11kV, 33kV Ultra-low EcoDesign losses
Power Series 10–63 MVA 33kV to 220kV Substation OLTC / ONAF
IEC 60076 & CE Certified Request Oil Quote

Quality & Compliance

Certified B2B Manufacturing & Laboratory Performance

Every transformer, compact substation, and switchgear unit is engineered under audited ISO quality management systems and type-tested according to IEC 60076 and ANSI C57 international standards.

IAF / CNAS Accredited

ISO 9001:2015 Quality System

Certified Quality Management System covering design, coil winding, vacuum drying, oil filling, and routine testing of 10kV–35kV distribution transformers.

Environmental System

ISO 14001:2015 Environmental

Environmental Management System certifying low-loss eco-designed core assemblies, zero PCB insulation oil, and environmentally safe production controls.

Occupational Health

ISO 45001:2018 Safety System

Occupational Health and Safety Management System ensuring safety containment in high-voltage testing bays and factory assembly protocols.

CNAS Lab Type Tests

IEC 60076 & GB Type Tests

Complete routine and type test records (temperature rise, impulse voltage withstand, short-circuit withstand) conducted at CNAS-accredited national research institutes.

SGS Audited Supplier

SGS Verified Manufacturer Audit

On-site factory audit certificate by SGS / Made-in-China, verifying manufacturing premises, export capacity, assembly lines, and legal qualification.

≥180 Units/Yr Export

International Delivery Certificate

Verified annual supply performance and delivery certificate for overseas power grid EPC and industrial infrastructure projects (Mozambique, Nigeria, Kenya, SEA).

FACTORY & TESTING WALKTHROUGHS

See XinHuan in Action (Production & Testing)

Factory tours, high-voltage routine test procedures, and production walkthroughs straight from our Hefei manufacturing base.

Company Tour

Corporate & Factory Tour

Hefei manufacturing base, automated workshops, and high-voltage testing laboratory.

Oil-Immersed

Oil Transformer Routine Testing

100% IEC 60076 voltage ratio, winding resistance, and dielectric routine testing.

Dry-Type

Cast Resin Dry-Type Quality

Epoxy resin vacuum casting, partial discharge testing, and temperature monitoring.

Production Floor

Transformer Assembly Floor

Precision copper winding, silicon steel core stacking, and vacuum drying chambers.

Production Line

Transformer Production Floor

Automated coil winding, precision core stacking, and vacuum drying chambers.

Switchgear

High-Voltage Switchgear

Vacuum circuit breakers, copper busbar routing, and relay protection cabinets.

Compact Substation

European Compact Substation

Prefabricated kiosk substation panel wiring, RMU integration, and LV distribution.

Dry-Type Assembly

Dry-Type Production Line

Copper foil winding, vacuum resin casting molds, and core-coil assembly.

Production Archives & Virtual Tours: Watch routine testing procedures, FAT walkthroughs & workshops.
360° Virtual Tour · XinHuan Official YouTube Channel

Engineering Reference Silo

Transformer Category Pillars & International Standards

China Transformer Manufacturer Export Hub
11kV Distribution Transformers IEC 60076

50–3150 kVA · IEC 60076 S11/S13/S20 hermetically sealed oil-immersed units with P0/Pk loss tables.
33kV Power & Feeder Transformers 170kV BIL

100 kVA–31.5 MVA · 170 kVp BIL lightning impulse & ONAN/ONAF cooling for utility grids.
60Hz ANSI/IEEE C57 Transformers ANSI C57.12

75–3000 kVA · 13.2kV / 13.8kV / 34.5kV DOE 2016 compliant for North & Latin America.
Pad-Mounted Transformers (ANSI) Dead-Front

75–3000 kVA · IEEE C57.12.34 tamper-resistant dead-front loop & radial feed cabinets.
2500 kVA Substation Transformers 2.5 MVA

2.5 MVA heavy industrial oil & cast resin units with Uk=6% short-circuit impedance.
11kV Cast Resin Dry-Type (SCB14) E2/C2/F1

100–3150 kVA · IEC 60076-11 Class F/H epoxy cast resin, E2/C2/F1 fire-safe, <5 pC PD.
Turnkey Compact Substations IEC 62271

100–3150 kVA · IEC 62271-202 prefabricated YBM European kiosk with MV RMU & LV panels.
Medical IT Isolation Transformers <150μA IT

3.15–100 kVA · IEC 60601-1 & IEC 61558-2-15 <150μA leakage for hospital operating rooms.
Harmonic K-Factor Transformers K-13 / K-20

50–2500 kVA · UL 1562 K-4 / K-13 / K-20 with 200% double neutral for data centers & VFDs.
Engineering Link Magnets & CAD Resources:
DWG / CAD Outline Drawings 1MVA & 2MVA Dry-Type Spec Sheet 10kV SCB13 Low-Loss Guide Solar & Wind Step-Up Units Short-Circuit & CFM Calculator P0/Pk Loss & TCO Calculator