For reliable power grid and industrial power distribution projects, our oil immersed transformer delivers stable performance. Covering 30kVA to 2500kVA at 10kV / 20kV / 35kV, the S11, S13, S20 and S22-M series rely on premium Baosteel Hi-B grain-oriented silicon steel. Furthermore, patented technology supports every unit, and we complete full routine tests following IEC 60076 international standard.
Oil Immersed Transformer Main Features
Our oil immersed transformer combines high-grade silicon-steel cores, precision winding, patented damping technology, and strict factory testing. Each unit delivers low no-load loss, low noise, and long service life for commercial, industrial, and power-grid applications.
Our Transformer Portfolio
✅ Oil immersed distribution transformer: S11, S13, S20, S22-M series
✅ Dry type transformer: SCB11, SCB13, SCB14, SCB18
✅ Amorphous core transformer: SH15 series
✅ Pole mounted transformer: single & three-phase, sealed tank design
✅ Capacity: 30kVA-2500kVA | Voltage: 10kV / 20kV / 35kV
Beyond the oil immersed line above, we also supply pole mounted substations and full EPC packages tailored to site requirements.
Raw Material
✅ Baosteel Hi-B grain-oriented silicon-steel
Standard S11/S13/S20 units use 0.27-0.30mm grade sheets. For high-efficiency S22 models, premium thin-gauge 0.23mm sheets serve as the core material. In fact, 0.20mm ultra-thin material is available for special custom requests.
✅ 100% oxygen-free copper winding conductor. High conductivity brings stable short-circuit resistance performance.
✅ High-grade insulating paper & mineral transformer oil. This raw material features excellent ageing-resistant dielectric property.
Production Technology
Core processing: CNC precision shearing cuts silicon-steel laminations, keeping burrs strictly controlled ≤0.03mm. 45° miter step-lap stacking technology helps disperse air-gap flux; this design reduces no-load core loss and running noise at the same time.
Winding process: Computer-controlled winding machines use adjustable tension-restraint devices. Uniform wire tension prevents winding dislocation or wire insulation damage. After winding, coils go through vapour-phase drying to reduce residual insulation moisture. Pressing and shaping then lock in stable mechanical strength for the finished coils.
Vacuum oil-filling: Vacuum degassing and automatic sealing happen right after oil injection. Dust and moisture stay isolated from insulation oil. Therefore, the service life of the whole insulation system gets extended greatly.
Patented Technology Adopted
① Patented Vibration-Damping & Noise-Reduction Device: A multi-layer spring-elastic buffer structure absorbs core vibration at the source. Built-in vacuum sound-insulating cavity and sound-absorbing cotton further weaken noise transmission. As a result, you will see a 5-8dB noise drop, making the unit suitable for installations near residential areas.
② Automatic Oil-Filling & Sealing Device: This integrated oil injection & self-sealing mechanism completes oil filling and sealing within one station. For example, it avoids dust contamination to insulating oil between separated oil-fill and manual-seal steps and lifts overall production consistency.
③ Adjustable Winding Restraint Device: Tension adjustment during coil winding stops conductor breakage caused by excessive pulling. Adaptive limit brackets maintain neat winding layers even when coil diameter expands.
④ Multi-direction Adjustable Quick-Mount Base & Spring-Lock Structure: A 360-degree rotation base and retractable mounting bracket come as standard. For pole mounted transformer projects, our spring-lock hook simplifies field installation & adjustment under complex site conditions.
Factory Routine Tests (Per IEC 60076-1)
- Winding DC resistance measurement
- Voltage ratio & vector-group verification
- No-load loss & no-load current test
- Load loss & short-circuit impedance measurement
- Power-frequency applied withstand voltage test
- Induced over-voltage withstand test
- Insulation resistance test; insulating-oil dielectric strength test
Every single unit goes through the full set of routine tests before delivery. Besides, type-test reports are ready for tender review whenever you require them.
About Us
Our oil immersed transformer and complete substation equipment are produced in our 40,000㎡ production plant. More than 100 sets of production and testing equipment fill the workshop, supported by experienced professional engineering and technical personnel. Meanwhile, we strictly follow GB and IEC standards, verify full type test documents, and track the whole production process for every single order.
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Email: info@yujinmech.com
WhatsApp/WeChat: +86 13871337862
Website: yujinmech.com