Smart energy water resistant tree-shaped intermediate voltage cable and production technology

Abstract

The invention discloses a smart energy water resistant tree-shaped intermediate voltage cable and a production technology. The cable is, from inside to outside, sequentially provided with conductors, a semiconductive inner shielding layer, an insulation layer, a strippable semiconductive outer shielding layer, a copper wire shielding layer, and a sheath. The insulation layer is a water resistant tree-shaped crosslinking polyethylene, and the copper shielding layer adopts sparse winding shielding. The sheath adopts linear low density polyethylene, and adopts a special extrusion type die for extrusion. The material of the sheath permeates in copper wire shielding gaps, and the copper wire shielding layer is pressed in the strippable semiconductive outer shielding layer, and a pressing depth is in a range from 0.10mm to 0.15mm. The smart energy water resistant tree-shaped intermediate voltage cable is advantageous in that the structure of the cable is compact, and an excellent waterproof tree performance is provided; by adopting the special extrusion type die, extrusion pressure and a shaping distance are improved, and the material of the sheath permeates in the copper wire shielding gaps, and the copper wire shielding layer is pressed in the strippable semiconductive outer shielding layer; and at the same time, the conductors are pressed tightly by a metal die, and therefore the structure of the cable is compact, and the excellent waterproof tree performance is provided.

Description

technical field [0001] The invention relates to a smart energy water tree resistant medium voltage cable and a production process. Background technique [0002] At present, medium-voltage power cables are mostly insulated with cross-linked polyethylene. Long-term operation of ordinary cross-linked polyethylene insulated cables in a humid environment during laying and operation will cause external moisture to penetrate into the cable and form water trees under the action of an electric field. The chance of the water tree is greatly increased, and the water tree branch is transformed into a permanent electric tree branch under the action of the electric field, which leads to insulation breakdown in a short period of time and greatly affects the service life of the cable. Many manufacturers in the market use water-blocking ropes and water-blocking tapes to improve the water-blocking performance of cables, so as to prevent water from immersing in the insulation and causing water...

AI Technical Summary

Problems solved by technology

[0002] At present, medium-voltage power cables are mostly insulated with cross-linked polyethylene. Long-term operation of ordinary cross-linked polyethylene insulated cables in a humid environment during laying and operation will cause external moisture to penetrate into the cable and form water trees under the action of an electric field. The chance of the water tree branch is greatly increased, and the water tree branch is transformed into a permanent electric tree branch under the action of the electric field, which leads to insulation breakdown in a short period of time and greatly affects the service life of the cable

Many manufacturers in the market use water-blocking ropes and water-blocking tapes to improve the water-blocking performance of cables, so as to prevent water from immersing in the insulation and causing water trees. This method can have a short-term water-blocking effect, but after long-term use The water-absorbing capacity of the water-blocking tape or the water-blocking rope decreases, and the water will still soak into the insulation, resulting in water trees

Images