Fault prevention of cold shrinkable cable accessories

In recent years, with the gradual improvement of the requirements for the safe operation and reliability of the power grid, the requirements for the maintenance and installation process of the equipment are finer and more precise, and the Cold Shrinkable Cable Accessories are used more and more widely.
In view of the many shortcomings of the cross-linked cable itself and the partial discharge or electric tree discharge of the cable terminal due to the lack of attention to details by the construction personnel in the production of Cold Shrinkable Accessories, we should strictly control the process in the future production process, and put forward the following preventive countermeasures and precautions:

1. The cross section of the semiconductor layer shall be smooth and flat, and the transition with the insulating layer shall be smooth;

2. Fill the air gap at the fracture of the cable insulating semiconductor layer with silicone grease to eliminate gas;

3. Strictly control the size of cable stripping and cutting, and each layer shall not damage the inner structure;

4. When stripping and cutting the copper shielding layer, it shall be fixed with tie tape or adhesive tape to prevent sharp corners and burrs at the fracture;

5. When grinding and cleaning the main insulation, the cleaning agent and sandpaper shall not touch the outer semi-conductive layer, so as to avoid the discharge caused by the dissolution of the semi-conductive layer by the cleaning agent and the unclean removal of impurities left by sandpaper grinding;

6. The size of accessories and the size of the cable to be installed shall strictly meet the specified requirements, and the appropriate amount of interference, especially the overlap between the stress tube and the insulation shield shall not be less than 20mm, so as to prevent the stress tube from separating from the insulation shield during shrinkage;

7. After the cable insulation layer is stripped and cut, the surface of the main insulation layer shall be carefully polished with fine sandpaper to make it smooth without knife marks and semiconductor residues. The surface of the insulating layer must be cleaned from the wire core to the semiconductor layer with cleaning solvent. It is strictly prohibited to clean the surface of the main insulating layer with cleaning paper that has touched the semiconductor shielding layer;

8. When making the cable terminal head, pay special attention to keep it clean and shorten the manufacturing time as far as possible. The longer the cable is exposed to the air after stripping and cutting, the greater the possibility of invading impurities, moisture, gas and dust, thus affecting the quality of the terminal head. Therefore, it is required to make full preparations before construction to ensure uninterrupted and one-off production.

For using Cold Shrinkable Accessories products produced by HUAYI CABLE ACCESSORIES Co.,Ltd., you can apply to the salesperson for installation instructions and installation guidance.