Crimped paper tubes

The primary functions of crimped paper tubes in oil-immersed transformers are as follows.

First, electrical insulation

Crimped paper tubes are made from electrical crimped paper with excellent dielectric strength. When fitted over leads or conductors, they effectively isolate different potentials, preventing inter-turn, inter-layer, or discharge to the core and tank, thereby enhancing overall insulation levels.

Second, Oil Resistance and Long-Term Stability

Crepe paper tubes exhibit excellent compatibility with transformer oil. They resist aging and cracking during prolonged oil immersion, maintaining stable insulation properties under high-temperature operating conditions. This makes them suitable for continuous, long-term transformer operation.

Third, Cushioning and Protection

The crepe structure possesses elasticity that absorbs vibrations and displacements during transportation and operation. This prevents direct contact between leads and hardware components like cores or clamps, reducing mechanical damage and insulation wear.

Fourth, Adaptation to Thermal Expansion and Contraction

Significant temperature fluctuations during transformer operation cause conductors to expand and contract. The expandable nature of corrugated paper tubes accommodates these changes, preventing insulation damage from stretching or compression.

Fifth, Enhanced Oil Flow and Heat Dissipation

The corrugated surface forms minute oil channels, facilitating transformer oil circulation around leads. This aids heat dissipation and improves localized cooling efficiency.

In summary, corrugated paper tubes serve multiple functions in oil-immersed transformers—providing insulation, protection, cushioning, and auxiliary cooling—making them a crucial foundational material in lead insulation systems.