Pultruded Strip for Dry Transformer
I. Product Introduction
Pultruded strips for dry transformer, also known as I-shaped insulating spacer, are insulating support profiles integrally formed through a continuous pultrusion process. The core is made of alkali-free glass fiber impregnated with thermosetting resin. The I-shaped structure is adapted to the internal installation space and stress requirements of dry-type transformers. The surface is smooth and free of defects such as bubbles and cracks.
II. Performances
High strength: Flexural/compressive strength ≥200MPa, tensile strength ≤900MPa, impact strength ≥90kJ/m², resistant to electrodynamic forces and coil self-weight.
High insulation: Insulation resistance ≥1.0×10¹²Ω under normal conditions (≥1.0×10¹¹Ω after 24h water immersion), dielectric strength ≥10kV/mm in transformer oil at 90°C, arc resistance ≥180s, comparative tracking index ≥600V.
High temperature resistance: Thermal class F/H (155–180°C), heat deflection temperature ≥240°C, resistant to aging.
Moisture resistance: Water absorption ≤20mg, no additional moisture protection required, stable performance in complex environments.
Easy processing: Smooth surface allows fast cutting and assembly, suitable for automated production.
Safe and reliable: Meets flame retardant standards, metal-free, does not interfere with electromagnetic performance.
III. Applications
Interlayer ventilation cooling: The I-shaped structure creates uniform ventilation gaps in dry-type transformers, accelerating heat dissipation, reducing coil temperature rise, and preventing overheating damage.
Insulation structural support: Used for coil to core and coil to enclosure support in dry-type transformers, as well as in reactors and line traps, dispersing electric field stress and reducing partial discharge risk.
High-voltage electrical equipment: Can be used as an insulation structural component in high-voltage frequency converter power modules, power capacitors, disconnectors, on-load tap changers, and other high-voltage electrical products.
IV. Technical Specifications
A full range of specifications is available. Common I-beam cross-section sizes include:
6×8 mm
8×8 mm
10×10 mm
16×20 mm
Custom sizes can also be manufactured according to customer requirements to accommodate the production of dry-type transformers with various power ratings and specifications.
