Oil Immersed Distribution Transformer Manufacturers – 6-132 kV Range
Subian Electric manufactures oil immersed distribution transformers from 6 kV to 132 kV class at its 50,000-square-metre factory in Xuzhou, Jiangsu, China. Since 2019, Subian’s 350+ employees have supplied utilities and distributors in more than 50 countries.
As a factory-direct manufacturer and supplier, Subian provides factory pricing, custom voltage and capacity configurations and complete test documentation.
Send your specification and target market. Subian’s export team will respond with a quotation, lead time and technical proposal.
Oil Immersed Distribution Transformers Manufactured by Subian
Oil immersed distribution transformers from 6 kV to 132 kV class – including 66 kV and 110-132 kV units, single-phase pole-mounted and three-phase designs – with routine testing on every unit.
What Is an Oil Immersed Distribution Transformer? Types & Buyer Guide
An oil immersed distribution transformer cools and insulates its windings with transformer oil, enabling economical, high-capacity distribution at voltages from 6 kV up to 132 kV class. It is the backbone of power distribution worldwide.
From rural pole-mounted units to large substation transformers, oil-immersed designs deliver proven reliability, excellent overload capability and easy maintenance – the reasons utilities continue to specify them.
What Buyers Check Before Ordering
- 6-132 kV class – complete oil-immersed range including 66 kV and 110-132 kV.
- Pole & pad designs – single-phase pole-mounted and three-phase ground units.
- 50,000m² factory – in-house winding, vacuum drying, oil filling and testing.
- 350+ employees – engineering, production and export teams.
- Type test evidence – reports to 110 kV class for project approval.
- OEM / ODM & wholesale – custom branding, packaging and volume supply.
Main Types of Oil Immersed Distribution Transformers
Subian manufactures three configurations:
Three-phase distribution
Configuration
Standard units from 30 kVA for grid and industrial distribution.
IEC / project specification
Single-phase pole-mounted
Pole-mounted
Compact units for rural and single-phase networks.
CSP or conventional tank / 5-500 kVA
High voltage 66-132 kV
Configuration
Larger units for regional distribution substations.
IEC / project specification
Oil Immersed Distribution Transformer Specifications
| Parameter | Specification |
|---|---|
| Rated voltage | 6 kV – 132 kV class |
| Rated capacity | 30 kVA – 63000 kVA |
| Frequency | 50/60 Hz |
| Cooling | ONAN / ONAF |
| Vector group | Yyn0 / Dyn11 / YNd11 |
| Standard | IEC 60076 / GB 1094 |
How to Compare Oil Immersed Distribution Transformer Suppliers
Quotations for this equipment often look identical on the first page. The difference sits in what is attached behind the number, and in the three or four lines that decide the installed cost rather than the purchase price.
| What to compare | What a thin quotation leaves out | What to ask for |
|---|---|---|
| Efficiency at 50 and 100% load | Nameplate kVA only | Measured efficiency points, or the loss figures needed to calculate them |
| Temperature rise | Silent on ambient | Design ambient, temperature-rise class and the derating above it |
| Noise level | No figure | Sound pressure in dB at 1 m, measured to IEC 60076-10 |
| Altitude and climate | Sea level assumed | Site altitude, humidity, and whether anti-condensation heaters are fitted |
| Vector group | Dyn11 assumed | The group the network uses, and whether the unit must parallel an existing one |
| Spares and service | Nothing beyond the unit | Fuse, gasket and tap-link availability, and the response time on a claim |
Buyers who compare on price alone usually discover the gap at commissioning. The six lines above are the ones that decide whether the unit or the panel can be energised without site work. OEM and ODM supply is available where the nameplate, manual and packing have to carry a different brand.
Recent Orders and Delivery Models
Equipment of this class is usually bought in small batches, tested at the factory and shipped as one consignment. Three references show how buyers in different markets specify it.
| Project | Location | Application | Supply model |
|---|---|---|---|
| 33kV main transformer ODM project | Zimbabwe | Mining | ODM supply |
| Oil-immersed transformer ODM supply | Libya | Building and construction | ODM, customer nameplate |
| Dry-type transformers, dual power supply | Pakistan | Dual-power distribution | Direct export |
Scope, packing and delivery notes for each project are in the project case library. Send the single-line diagram and the destination port and the reply follows the same structure.
How Manufactured by Subian Oil Immersed Distribution Transformers
Material preparation, winding, vacuum drying, oil filling, assembly, inspection and packing follow controlled procedures at Subian’s Xuzhou facility.
Production Workshop
Controlled winding, core processing and vacuum drying with quality checkpoints between every stage, so quality is built in from the start.
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Quality & Testing Center
Routine inspection on every unit before delivery, with type test reports supporting project approval and market certification.
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Materials & Components
Core materials, windings and components are checked against the approved bill of materials on every production run.
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OEM / ODM / Agency Supply
Custom branding, packaging and configurations for global partners – from nameplate to complete product design – supported by a dedicated export team.
Learn More →OEM/ODM & Wholesale Oil Immersed Transformer Supply for Distributors
Brand or resell oil-type units with custom nameplates, packaging and documentation from Subian’s factory.
OEM / ODM
Factory-DirectCustom branding, packaging and product variants built on Subian’s standard platforms – from a nameplate to full product design.
Custom nameplate · Custom packaging · Full test docs
Wholesale Supply
Volume PricingFactory pricing with flexible container quantities, mixed models per container and reliable global shipping for volume buyers and importers.
Container MOQ · Mixed models · Global shipping
Distributor Support
Channel PartnersDedicated account management, technical documentation and priority production for distributors and project clients.
Account manager · Sales material · Priority lead times
Pole-Mounted vs Pad-Mounted Oil Immersed Transformers
Pole-mounted units serve overhead rural networks and are economical per kVA. Pad-mounted units sit at ground level in enclosures, suiting urban and commercial sites where overhead lines are not permitted.
Both are built on Subian’s oil-immersed platforms – the choice follows your network configuration and site requirements.
Oil Immersed Distribution Transformer Manufacturers: How to Choose
Evaluate manufacturers on vacuum drying quality, type test evidence and utility reference deliveries. These are the real predictors of transformer life.
Subian Electric offers a 50,000m² factory, 350+ employees, ISO9001, CE and UL certification and export to 50+ countries with a complete 6-132 kV range.
Request a quotation with your voltage, capacity and standard – Subian confirms the design before production.
Certifications & Quality Assurance
Subian’s oil-immersed transformers are produced under ISO9001, ISO14001 and ISO45001 management systems, with CE and UL certification and type test reports.
Product Certifications
10 kV Dry-Type Transformer Certificate
35 kV Transformer CB Certificate
35 kV Transformer CE Verification
Transformer CE Certificate
Dry-Type Transformer Test Verification
ISO 14001 Environmental Management
ISO 45001 Health & Safety
ISO 9001 Quality Management
110 kV Transformer Type Test Report
UL Certificate of Compliance
Oil Immersed Distribution Transformer FAQ
Answers to the questions utilities and distributors ask most about oil immersed transformers.
What voltages do you manufacture?
What is the difference between distribution and power transformers?
Can you build single-phase pole-mounted transformers?
What cooling systems are available?
What is the minimum order quantity?
Why is transformer oil used in distribution transformers?
How is Oil Immersed Distribution Transformer tested before shipment?
What documents come with Oil Immersed Distribution Transformer?
Contact Subian
Need the Right Specification?
Tell Subian your target market, product type, quantity and technical requirements. Subian’s team will help you identify a suitable configuration for your project.