Cold shrink tube is a component that uses elastomer materials (commonly used silicone rubber and ethylene propylene rubber) to be injected and vulcanized in the factory, and then expanded and lined with plastic spiral supports to form various cable accessories. During field installation, these pre-expanded parts are put on the treated cable ends or joints, and the plastic helical strips (supports) that are internally supported are pulled out and pressed against the cable insulation to form a cable accessory.

　　Cold shrink tube is generally used, and the voltage level is from 10kv to 35kv. Cold-shrinkable cable joints, 1kv class adopts cold-shrinkable insulating tube for reinforced insulation, 10kv class adopts cold-shrinkable insulation parts with inner and outer semi-conductive shielding layers. Cold-shrinkable branch sleeves are used at the terminal forks of the three-core cable.

　　The cold shrink tube accessories have the advantages of small size, convenient operation, rapid operation, no need for special tools, wide application range and few product specifications. Compared with heat-shrinkable cable accessories, it does not need to be heated by fire, and moving or bending after installation will not cause the risk of disengagement between the internal layers of the accessories as with heat-shrinkable cable accessories (because cold-shrinkable cable accessories rely on elastic pressure. tightness).

　　It must be pointed out that before the cold shrink tube is installed on the cable, the components of the prefabricated cable accessories are not under tension, while the cold shrinkable cable accessories are under high tension, so it must be ensured that during the storage period, the cold shrinkable cable accessories are in a state of high tension. The components should not have obvious permanent deformation or elastic stress relaxation, otherwise, after being installed on the cable, sufficient elastic pressing force cannot be guaranteed, so that good interface characteristics cannot be guaranteed.