Installation Guide for Triple Layer Heat Shrinkable Tubing
The selection of triple layer heat shrinkable tubing is only the first step in the construction of medium voltage cable joints. Pre-installation size confirmation, cable and joint surface treatment, heat shrinkage process, and final inspection can affect whether the heat shrink tube maintains a good fit in the joint area. From the perspective of actual installation, this paper will introduce several key links worthy of attention in the construction of three-layer co-extruded composite heat shrink tubing.
Verify the Joint Size Before Installation.
Heat shrink tubing is not the larger the specification, the easier it is to install. Before installation, it is necessary to confirm the maximum outer diameter of the actual cable joint, the length to be covered, and the cable voltage level, and then match the corresponding specifications. CCMT's standard specifications for triple layer heat shrinkable tubing cover different inner diameters and wall thicknesses and provide a 2.5:1 shrinkage ratio.
During the procurement stage, providing the maximum outer diameter, coverage length and voltage level of cable joints can help suppliers further confirm appropriate product specifications. This is very important because specification matching is not only related to whether heat shrinkage can be completed, but also whether the tube body and the joint area can form a good fit after heat shrinkage.
Keep Installation Areas Clean Before Heat Shrinking.
Before installing heat shrink tubing, focus on inspecting the cable joint area that needs to be covered to avoid obvious dust, oil stains or other foreign matters on the surface that affect the fit.
Heat shrink tubing is not an ordinary protective sleeve that works independently. For example, the three-layer structure of CCMT's product consists of a semiconductive layer, an insulating layer and an elastic layer, which respectively undertake functions such as electrical stress control, insulation protection and elastic recovery. Therefore, surface treatment before installation is also an important part to ensure that the product functions normally.
Control the Heating Process According to Product Requirements.
The heat shrink installation temperature of our triple layer heat shrinkable tubing is 135 - 150°C. During construction, heating should be carried out in accordance with the technical requirements of the product to fully recover the pipe body and fit it with the cable joint area.
It should be noted that heat shrinkage is not simply a matter of "heating the tube until it shrinks." Reasonable and uniform operation should be maintained during the heating process to avoid local excessive heating or insufficient shrinkage.
Especially for this kind of thick-walled heat shrinkable products, this is even more worthy of attention. CCMT adopts a cross-linked thick-walled structure and has high resilience. After heat shrinkage, it can continue to maintain shrinkage pressure on the joint area to adapt to the size change of the cable insulation layer due to temperature changes during operation.
Check the Final Status After Heat Shrinkage Is Completed.
Installation inspection should not be completed immediately after heat shrinkage is completed. Suggestions focus on confirming:
· Whether the tube has been fully restored;
· Whether the pipe body and the joint area maintain good fit;
· Whether there are obvious abnormalities on the surface;
· Whether the covering length meets the design requirements;
· Whether there is obvious overheating, damage or insufficient shrinkage during the heat shrinkage process.
The installation quality ultimately needs to serve the insulation and electrical stress control requirements, so the status inspection after completion of heat shrinkage cannot be ignored.
Why Is the Three-Layer Co-Extrusion Structure Suitable for Medium Voltage Cable Joints?
Unlike ordinary heat-shrink tubing with a single function, triple layer heat shrinkable tubing integrates semiconducting layers, insulating layers, and elastic layers into one tube body.
Take CCMT's triple layer heat shrinkable tubing as an example. It adopts a cross-linked thick-walled structure and has high resilience; its products are suitable for insulation treatment of cable joints with voltage levels of 6 - 36kV, and can be used for insulation treatment of cable joints up to 42kV. and partial discharge control needs. The operating temperature range of the product is-55 ° C to 105°C. These structural and performance designs make it more suitable for use in cable joint areas where insulation, electrical stress control, and long-term fitting are required.
In addition, CCMT has the mass production capacity of three-layer co-extrusion composite heat shrink tubing, and the supply capacity of heat shrink products is approximately 5 million meters/month. It also supports specification customization and production based on technical parameters confirmed by customers.
The reliable application of three-layer co-extruded composite heat shrink tubing depends not only on selecting the correct size, but also on size matching, installation preparation, reasonable heating and post-completion condition inspection. It is recommended that the purchaser directly provide the actual connector size and voltage level during the inquiry stage, which can make the confirmation of product specifications more accurate and help reduce mismatch problems during field installation.
If the project has special installation size or structural requirements, the actual installation size can be further provided, and we will assist in confirming the specifications.
