Tie up and repair damaged wires
In operation, conductors and lightning arresters are subjected to mechanical action of various forces, thermal action of load current, short circuit current and lightning current, as well as electrochemical corrosion and chemical corrosion, which may cause damage to conductors.we are provide AAAC dead end grip,you can know it.
Common defects of conductors and lightning arresters are broken strands, loose strands, joint heating, arc burns, rust, corrosion, burrs, broken wires, etc.
If there is a defect, the following treatment methods should be adopted to deal with it.
1. trimming edges and corners, burrs
In the course of laying out or transportation, the edges and burrs caused by the collision or dragging of lightning arrester wires with hard objects, steel-core aluminium alloy strands or lightning arresters whose damage cross-sectional area is 5% or less of the cross-sectional area of the conductive part and whose strength loss is less than 4%, can not be repaired, and can be rubbed flat along the strand direction with No. 0 sandpaper, and cleaned with sandcloth.
2. Winding Reinforcement Method
When the damage of the conductor at the same section exceeds the standard of polishing treatment and the damage section area is 7% or less of the cross section area of the conductive part, a single strand of the same metal (conductor diameter should not be less than 2 mm, galvanized iron wire for steel-cored aluminium strand) should be used to wrap the damaged part. The winding center should be located at the most serious part of the damage, the winding should be close, and the damaged part should be covered completely, and the length should not be less than 2 mm. 100 mm, the two ends of the damaged part should exceed 30 mm.
3. Repair Method
When the damage cross-section area of conductor is 7%-25% of the cross-section area of conductive part, the repair method is adopted.
When using laying repair, the laying length should exceed the damaged part, and the winding length at both ends should not be less than 100 mm; when using repair block, the repair block should exceed the damaged part of the conductor by 30 mm.
Pre-stranded wires first appeared in the United States in the 1940s and 1950s. The initial products are spiral protective wires for bare conductor stress concentration position, electric corrosion and arc burning position protection.
After years of development, pre-stranded wire fittings have been widely used in power transmission and distribution, optical fiber communication, electrified railway, cable television, construction, agriculture and other fields.