Insulation Crepe Paper: The “Wrinkled Armor” of Power Equipment

Insulation Crepe Paper: The “Wrinkled Armor” of Power Equipment Inside the steel structures of transformers and inst...

Insulation Crepe Paper: The “Wrinkled Armor” of Power Equipment

Inside the steel structures of transformers and instrument transformers, a brown paper material covered with uniform creases quietly withstands high voltage and hot oil immersion environments—it is insulation crepe paper. Although seemingly simple, it serves as an invisible guardian that ensures the safe operation of power grids.

Product Breakdown: The Technology Behind the Creases

Structural Design

Manufactured from sulfate wood pulp through wet-forming and creping processes, insulation crepe paper features a unique corrugated structure that provides an elongation rate of ≥120%, allowing it to bend without breaking and perfectly conform to complex conductor shapes.

Outstanding Performance

Electrical Insulation Barrier

Breakdown voltage ≥10 kV/mm (0.46 mm thickness)

Forms an “oil-paper insulation system” together with transformer oil

Helps balance electric field distribution and prevents partial discharge

Environmental Resistance

High temperature resistance

Excellent salt spray corrosion resistance

Low sensitivity to moisture and humid environments

Strict Quality Control

The crepe pattern must be uniform and free from damage, with clean-cut edges and thickness tolerance controlled within ±0.05 mm. The surface must be free from pinholes, water stains, or pulp lumps.

Common specifications include:

Thickness: 0.35–0.80 mm

Width: 30 mm / 50 mm

Custom widths available up to 700 mm jumbo rolls

Application Overview:From Traditional Transformers to Ultra-High Voltage Equipment

Protecting the “Lifeline” of Transformers

Lead Wire Wrapping

Used for wrapping transformer conductors and lead wires, insulation crepe paper resists cracking during bending and protects leads from compression damage.

Breakthroughs in Localization of High-End Equipment

Dry-Type Bushings

Domestic insulation crepe paper has been successfully applied in 110kV resin-impregnated paper bushings, achieving dielectric and mechanical performance comparable to imported materials.

UHV DC Equipment

Combined with epoxy resin to form advanced insulation systems, crepe paper has become a key material for HVDC bushings and ultra-high-voltage applications.

Expansion into Emerging Applications

Semiconductor Shielding

Black semiconductor crepe paper is used in instrument transformers below 750kV to balance electric fields and control partial discharge.

Transposed Conductor Insulation

0.46 mm and 0.8 mm crepe paper is widely used as interlayer insulation in winding conductors due to its strong oil absorption capability and enhanced heat dissipation performance.