The end sleeve is designed for mounting on three-core cables with plastic or oil-impregnated paper insulation. It reliably protects cable transmission lines from moisture, dampness, solar radiation, conductive dust, chemically aggressive substances and environments, and from a variety of negative atmospheric effects.
Unlike the coupling, the end coupling is used only outdoors. Today there is a huge variety of models of such devices, the application of which depends mainly on the design of the cable, its characteristics and operating conditions. For example, heat-shrinkable end sleeves KNTp are designed for cables with AC voltage up to ten kW. Such devices have high tightness, good mechanical and thermal strength, and have a low cost.
For installation on cable lines with voltage up to one kW, an end sleeve is usedPKNTp-1kV models. Devices of this design are characterized by excellent thermal insulation properties and resistance to ultraviolet radiation. The end coupling, depending on its purpose, may have a steel, aluminum or cast iron body.
The separated cable cores are insulated with tubes made of a material resistant to the adverse effects of the environment. The cutting spine is equipped with a thermofusible cone-shaped filler, which serves to equalize the electric field strength, it is insulated with a special glove.
When installing this product, lugs equipped with contact shear screws are installed on the cores of the power cable. The tips are carefully insulated, and their connection to the ground conductor is made by soldering. In order to protect the spine from splitting, a special spacer is installed on it. Depending on the design of the cable, the end sleeve is equipped with phase insulators based on a pair for each core.
Structurally, the cable end sleeve consists of a body, a glove with hot-melt adhesive applied to its surface, heat-shrinkable tubes for insulating cable cores and cuffs. The device is also supplied with fittings designed to connect the ground wire, and lugs with shear-type bolt heads.
Before installation, carefully check the dimensions of the coupling. Particular attention should be paid to the location of the outer insulator heads relative to the fronthull surface. It is on this that the installation technology to a large extent depends. The location of the heads must correspond to the contacts of the connected cable. After this check, the gland is removed from the coupling body, the necessary slot is selected in it, the diameter of which corresponds to the thickness of the cable being inserted.
Branch pipes are inserted into the openings of the housing, which are then pushed onto the cable cores. The extreme cores are carefully bent, then inserted into the corresponding slots in the body. The body itself should be advanced in such a way that the middle core comes out of it approximately 280 mm. Further, in full accordance with the requirements of the technology specified in the accompanying technical documentation of the product, it is necessary to proceed with the assembly of the contact heads and extreme insulators on the case. Finally, the core ends are connected to the contact bars of the insulator heads, after which they are securely fixed with bolts.
