35KV Oil-Immersed Transformer
Your Leading 35KV Oil-Immersed Transformer Supplier
Trust In Grid Co., Ltd. is a professional transformer manufacturer, specializing in the design and production of power transformer, high-voltage switchgear, power distribution equipment, energy storage systems (ESS), magnetic wire, bushing and machining parts. Our power transformers are available in 500KV, 330KV, 220KV, and 110KV models, and are widely used in power utilities, renewable energy systems (solar and wind), industrial facilities, data centers, transportation infrastructure, and OEM applications.
Why Choose Us?
Production Capacity
With 6 factories covering 240,000 m², over 2,000 employees, and 200+ engineers, we support large-scale projects and long-term global supply with more than 30 years of export experience.
Advanced Equipment
We operate a complete set of in-house production equipment, including cutting, winding, CNC machining, vacuum drying, and testing systems, with over 450 machines ensuring stable quality and efficient output.
Quality Control
All products are manufactured and tested in compliance with IEC, IEEE, ANSI, CSA, UL/cUL, CE, and ISO 9001:2015 standards, ensuring reliable performance and smooth international approval.
OEM & ODM Capability
Our engineering team provides OEM/ODM support, including customized design and technical optimization, delivering tailored solutions for utility, industrial, and renewable energy projects.
Specifications of 35KV Oil-Immersed Transformer
|
Parameter |
Typical Range |
|
Rated Voltage |
35kV (HV) / 3.3kV – 10kV (LV) |
|
Rated Capacity |
5 MVA – 50 MVA |
|
Frequency |
50Hz / 60Hz |
|
Phase |
Three-phase |
|
Cooling Method |
ONAN / ONAF |
|
Insulation Medium |
Mineral insulating oil |
|
Insulation System |
Oil-paper insulation |
|
Tap Changer |
Off-circuit or OLTC |
|
Tapping Range |
±5% or ±2×2.5% |
|
Vector Group |
Dyn11 / YNd11 / Yyn0 |
|
Impedance |
Typically 6% – 10% |
|
Core Material |
CRGO silicon steel |
|
Losses |
Low no-load & load loss design |
|
Installation |
Outdoor / substation |
|
Protection Devices |
Buchholz relay, oil level indicator, temperature sensors |
|
Standards |
IEC 60076 / IEEE / ANSI |
Superior Thermal Performance
Oil has a higher heat capacity and thermal conductivity compared to air or resin, allowing for efficient cooling even under heavy loads.
Long Service Life
With proper maintenance and oil monitoring, these transformers often operate reliably for 30 years or more.
High Insulation Strength
Oil provides strong dielectric insulation, preventing flashovers and maintaining stable voltage levels under varying operating conditions.
Cost-Effectiveness
Oil immersed designs offer lower upfront and lifecycle costs compared to equivalent dry-type units.
Flexibility in Power Ratings
They are suitable for small distribution units (100 kVA) up to high-voltage grid transformers exceeding 250 MVA.
Power Generation and Transmission: Essential in power plants and high-voltage substations.
Industrial Facilities: Ideal for factories and plants with high load demand.
Distribution Networks: Common in both urban and rural substations.
Renewable Energy Projects: Used in solar farms and wind turbine applications.
Transportation Infrastructure: Employed in railway systems and traction substations.
Manufacturing Process
Core Lamination Process
The transformer core is manufactured using high-grade CRGO silicon steel to minimize core loss and improve efficiency.
01
Winding Process (Copper / Aluminum)
Windings are produced using high-conductivity copper or aluminum, depending on project requirements.
02
Vacuum Drying & Oil Filling
This process ensures optimal insulation performance and long-term reliability.
03
Testing & Quality Control
Each transformer undergoes strict testing procedures in accordance with international standards.
04
Final Assembly & Packaging
Final assembly ensures mechanical integrity and readiness for transportation and installation.
05
Customization Options
Voltage: Optional
Capacity: Optional
Impedance: Optional
Cooling: Optional
OLTC: Optional
MOQ: Customizable
Comparison of 35KV Oil-Immersed Transformer and Dry-Type
Transformer
|
Feature |
Oil Immersed Transformers |
Dry-Type Transformers |
|
Cooling System |
Mineral Oil |
Air |
|
Fire Risk |
Higher |
Lower |
|
Environmental Considerations |
Requires Spill Management |
Minimal |
|
Ideal Installation |
Outdoor, Industrial |
Indoor, Sensitive Locations |
Maintenance and Safety Considerations for Oil-Immersed Transformers
Oil-immersed transformers have maintenance and safety considerations. Keeping your transformer well-maintained can lengthen its lifespan and reduce the risk of safety issues.
You should perform regular visual inspections and cleanings. Check the transformer to ensure that all parts are in good condition and that there is no threat of leaks. Make sure that all fittings are tight. Clean the exterior and interior of the transformer to remove dust, dirt, and other debris.
It's also essential to check the oil frequently. Make sure that the oil is at its proper level. You should also take samples of the oil and have it tested. You don't want to use contaminated oil. Finally, keep an eye on the temperature and air pressure. You want to be sure that the transformer is within the suggested levels.
As with any electrical equipment, there is always a risk of fire. In the event of a fire, it's important to ensure that the oil doesn't leak out from the transformer. Oil can cause the fire to spread, making a hazardous situation even more dangerous.
Payment Terms
T.T with 30% downpayment, 70%before shipment.
Paypal or West Union also accept.
Our Service Highlights
Pre-Sales Consultation & Design Support
Early technical engagement to define requirements and deliver optimized solutions.
During Sales & Project Execution
Transparent project management with controlled production, quality tracking, and on-time delivery.
Warranty Advantage
Minimum 2-year warranty on all products, ensuring reliable and risk-free operation.
After-Sales Support
24/7 technical support with fast response, spare parts availability, and training services.
Long-Term Partnership
Lifelong technical support and upgrade guidance for sustained performance.
Packaging & Shipping
Packaging details:
Shockproof foam/moisture-proof film, professional export cartons/wooden crates/pallets.
Final assembly ensures mechanical integrity and readiness for transportation and installation.
Certificates
We're well-known as one of the leading 35kv oil-immersed transformer manufacturers and suppliers in China, also support customized service. Please feel free to buy high quality 35kv oil-immersed transformer made in China here from our factory. Contact us for more details.
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