Cross-linked cable usually means that the insulation layer of the cable is cross-linked material, and the most commonly used material is cross-linked polyethylene (XLPE).
The process is to make the linear molecular structure of polyethylene (PE) material through a specific processing method to form a three-dimensional network branch structure of cross-linked polyethylene. The long-term allowable operating temperature is increased from 70 °C to 90 °C (or higher), and the short-circuit allowable temperature is increased from 140 °C to 250 °C (or higher), which greatly improves the actual performance under the premise of maintaining its original excellent electrical properties.
Euro cable plugging head
Cable accessories are widely used because they solve the problem of cable connection in overhead line change cables and the characteristics of full insulation, full sealing, maintenance-free, and flexible installation combination. Cross-linked cables are most commonly used in the actual use of 10kV distribution networks. The cable accessories used in the mirror refer to the terminal head and the intermediate head, as well as the cable distribution box. The oil-paper insulated cable terminations traditionally used in the early days are now rarely used. Now the most common use of heat shrinkable cable head and cold shrinkable cable head and cold shrinkable intermediate head, of which cold shrinkable cable head and cold shrinkable intermediate head are also called prefabricated cable accessories, in the distribution network cableization cable distribution box has been widely used. And prefabricated cable accessories are also suitable for various harsh environments because of full insulation, full sealing, full shielding, reliable guarantee of equipment and personal safety, greatly improve the reliability of power supply, so it is the direction of future development.
Heat shrink cable attachment 3
Cross-linked polyethylene (XLPE) insulated power cables (hereinafter referred to as cross-linked cables) will produce dendritic discharge channels under the action of electric field and water, a phenomenon called water trees. Water trees will continue to grow over time, eventually leading to insulation breakdown, which becomes an important cause of early damage to power cables.
35kV three-core intermediate connector
The production and application of ordinary cross-linked cables has a history of nearly thirty years, which has excellent electrical and mechanical properties in a dry environment, but in the actual application of the cable laying environment is usually relatively harsh, the cable often needs to be short-term or long-term immersed in water, or in a humid and humid environment, and ordinary cross-linked cable does not have the ability to resist water trees at all, in long-term use insulation will gradually absorb moisture in the environment, and then because of the cable insulation in a large number of tiny voids, so in the micropores will be full of moisture, Water-filled micropores can produce water trees at very low voltages. Under the long-term action of the electric field, a large number of water branches will be triggered in the cable insulation layer, and the aging of the water tree will crack the insulating molecules; When the water tree in the micropores reaches a saturated state, the electrical and mechanical properties of the insulation will decrease sharply, and the conductive water branches (electric branches) will lose a lot of electrical energy, and eventually cause the breakdown of the cable insulation layer, thereby greatly reducing the cable life.
返回顶部