What is ACSR? Steel core aluminum stranded wire is formed by twisting aluminum wire and steel wire, which is suitable for overhead transmission lines. It has a steel "core" inside, and an aluminum wire wrapped around the steel core by twisting on the outside; the steel core mainly increases the strength, and the aluminum stranded wire mainly transmits electric energy. For high-voltage transmission lines, due to The path of the line is limited, and it is impossible to set up multiple lines on one path.
People came up with a method that uses one path, a set of iron towers, and multiple wires, that is, one line is equivalent to multiple lines; for 500KV transmission Lines, most of our country uses the method of hanging four wires, which is named "four-split line". In fact, these four-split lines are ordinary four steel core aluminum stranded wires. There is nothing special, not one is steel, three It is aluminum; Functions and advantages: ACSR has simple structure, convenient erection and maintenance, low line cost, large transmission capacity, and is conducive to laying across rivers and valleys and other special geographical conditions. It has good electrical conductivity and sufficient Features such as high mechanical strength, high tensile strength, and expandable tower pole distance. Therefore, it is widely used in overhead transmission and distribution lines of various voltage levels.
Our commonly used "steel core aluminum stranded wire" refers to the bare wire. The old standard model was LGJ. From the name, we can see that it has a steel "core" inside and an aluminum wire wound by twisting the outside. Around the steel core; the steel core mainly plays the role of increasing strength, and the aluminum stranded wire mainly plays the role of transmitting electric energy;
At present, the latest national standard for steel-cored aluminum stranded wire is GB/T 1179-2017 "Round Wire Concentric Stranded Overhead Conductor". The main models are based on the nature of the steel used. There are the following categories:
For high-voltage transmission lines, due to the limited path of the line, it is impossible to build multiple lines on one path. People came up with one path, a set of iron towers, and multiple wires. That is, one line is equivalent to multiple lines. Line method; for 500KV transmission lines, most of our country uses the method of hanging four wires, which is named "four-split line". In fact, these four-split lines are ordinary four steel core aluminum stranded wires, and there is nothing special. , Not one is steel, three are aluminum;
Corresponding to "bare" wires, there are also overhead insulated wires, mostly JKLYJ, which are overhead aluminum cross-linked polyvinyl chloride encapsulated wires; they have been widely used in Chinese cities and power distribution systems that require relatively high power supply reliability. Although the price is high, it is the development direction of distribution lines.
The steel core aluminum stranded wire is a bare wire, which belongs to the special overhead power line. As long as the installation is carried out in accordance with the relevant specifications, the safety distance is ensured, and the tower has a good grounding magnetic bottle, and meets the power transmission level dependent height, span, deflection, and tower strength specifications In addition, during the laying process of ACSR, each tower has a certain distance and height requirements and the requirements of the ACSR and the ground. The phases are insulated by air. Therefore, under normal circumstances, Don't worry about exposed wires.