Cable accessories come in a wide variety, each with its own characteristics and limitations, and generally cannot be substituted for one another. Common types include:
Wrapped Type: Cable accessories made by wrapping self-adhesive rubber tape around the cable on-site. These accessories are prone to loosening, have poor fire resistance, and a short lifespan.
Cast Type: These accessories are cast on-site using thermosetting resins as the main material. Materials used include epoxy resin, polyurethane, and acrylic resin. A fatal flaw of this type is the tendency to generate air bubbles during curing.
Molded Type: Primarily used for intermediate cable connections, these accessories are molded and heated on-site to fuse with the cable. The manufacturing process is complex and time-consuming, and they are not suitable for terminal joints.
Cold Shrink Type: These accessories are pre-expanded in the factory using elastomers such as silicone rubber and EPDM rubber, and then molded with plastic support strips. During on-site construction, the support strip is removed, causing the pipe to shrink onto the cable due to the inherent elasticity of the rubber, thus creating a cable accessory. This accessory is best suited for construction sites where open flame heating is not possible, such as mines and petrochemical plants.
Heat-shrink type: This type of accessory is made by manufacturing different components of a rubber-plastic alloy with a "shape memory effect," which are then heated and shrunk onto the cable on-site. This accessory is lightweight, easy to install, reliable, and inexpensive.
Prefabricated type: This type of accessory is made by injection molding different components from silicone rubber, followed by one-time vulcanization, retaining only the contact interface. It is inserted into the cable during on-site construction. This construction process minimizes unpredictable adverse environmental factors, thus this accessory has significant potential value and represents the future direction of cross-linked cable accessories. However, its manufacturing technology is highly complex, involving multiple disciplines and industries. Prefabricated accessories still use heat-shrinkable materials for installation below the cable's three-way junction and shielding, therefore, it is actually a combination of prefabricated and heat-shrinkable types.