What is a dry-type transformer?

I. Core Definition: Oil-Free Insulation Technology Innovation

Dry-Type Transformer is a power transformer that does not rely on liquid insulation medium. Its windings and core are directly exposed to air or encapsulated with solid insulating materials. Through high-grade insulation materials and special cooling technology, it achieves the same power conversion function as oil-immersed transformers, while offering higher safety and environmental friendliness.

Using natural air cooling or forced air cooling, it avoids the risks of oil leakage and fire associated with oil-immersed transformers, making it particularly suitable for safety-critical locations.

II. Structural Features: Triple Protection Insulation System

1. Winding Insulation:

   • Epoxy resin casting: Vacuum cast molding, insulation class F (155℃) or H (180℃)

   • Impregnation treatment: Multiple impregnations with high-temperature insulating varnish

2. Core Structure:

   • High-quality cold-rolled silicon steel sheets, 45° full mitered joints

   • Stepped lap construction, reducing no-load loss by 20-30%

3. Cooling System:

   • Natural air cooling (AN)

   • Forced air cooling (AF), capacity increase 40-50%

III. Performance Advantages: The Smart Choice for Safety and Environment

Additional advantages:

• Strong overload capacity: Short-term overload up to 150%

• Easy installation: No oil pit or fire wall needed

• Easy smart integration: Temperature monitoring systems

IV. Applications: Safety-First Critical Locations

1. Indoor distribution:

   • Commercial centers: Beijing CBD uses SCB13 dry-type transformers

   • Data centers: Alibaba Zhangbei data center with thousands of dry-type transformers

2. Special environments:

   • Subway tunnels: Guangzhou Metro Line 3 uses dry-type transformers throughout

   • Offshore platforms: Bohai oil field platforms with anti-salt spray type

3. Sensitive locations:

   • Hospital operating rooms: Ensuring no oil contamination risk

   • Chemical plants: Explosion-proof and corrosion-resistant requirements

V. Technical Parameters: Precision Engineered Performance

Electrical performance:

• Capacity range: 30kVA-20MVA

• Voltage level: 10kV-35kV

• No-load loss: 20-30% lower than national standard

• Load loss: 15-25% reduction through optimized design

Insulation performance:

• Insulation class: F or H

• Temperature rise limit: 100K (F), 125K (H)

• Protection level: IP00-IP23

Environmental performance:

• Noise level: ≤55dB (at 1m)

• Recycling rate: ≥95%

• Hazardous substances: RoHS compliant

VI. Selection Guide: Choosing the Right Model

1. By usage environment:

   • Ordinary indoor: IP20 protection

   • Humid environments: IP23 protection

   • Corrosive environments: Special coating treatment

2. By load characteristics:

   • Stable load: Standard models

   • Impact load: Enhanced insulation models

   • Nonlinear load: K-factor transformers

3. By efficiency requirements:

   • Level 1 efficiency: SCB13 and above

   • Super level 1 efficiency: SCB14, SCB18

   • Amorphous alloy: 70% lower no-load loss