1. The temperature of the thick walled part of the insulation aluminum coil drops rapidly, causing shrinkage force first, while the temperature of the thick walled part or the hollow tube part drops slowly, with almost no shrinkage force.
2. Thick walled cross-section with small shrinkage force, or cleared by driving force.
3. The insulated aluminum coil leaves the unwinding machine, and the temperature drops again.
4. A portion of the thick wall or a portion of the hollow tube has a relatively large cross-section, which gradually causes a significant contraction force as the temperature decreases. However, a significant decrease in temperature in a portion of the thick wall will no longer cause contraction force or result in a smaller contraction force.
5. The cross-sectional shrinkage force of aluminum coil is uneven, and the insulation aluminum coil bends towards thick walls or hollow pipes along the compression direction.