Demand for heat-resistant aluminum alloy conductors
In the construction of power lines in China, especially in the western region, there are more and more areas with large span or large drop, which need to use conductors that can not only transmit large current, but also bear large tension. Although the unit price of heat-resistant aluminum alloy conductor is 1.58 times of that of common conductor, its comprehensive cost is much lower than that of common conductor. Because it can replace the common overhead conductor, save land resources, simplify the structure of the line, save many parts and components, do not need large investment in the transmission line with the same conductive section, especially in the narrow area of the line corridor, only need to replace the conductor with the similar conductive section, basically do not need to replace the tower, which can meet the requirements of strength and safety of the conductor to the ground scale The transmission capacity is increased by 40% - 60% at the same time. Due to the improvement of the conductivity, a lot of investment can be saved in the line engineering. According to the calculation, the difference of conductivity is 1 percentage point. Under the condition of 220kV voltage, the economic current density transmission will reduce the power loss per kilometer by about 200000 yuan according to the current electricity price.
According to the data, 60% heat-resistant aluminum alloy conductor with conductivity has been widely used in Japan to replace the ordinary steel cored aluminum strand, accounting for 70% of the total length of transmission lines in the country. At present, the tensile strength of high-strength heat-resistant aluminum alloy wire in Japan is 225MPa (diameter 4.0mm), 41.5-46.7% higher than that of 58% IACS and 60% IACS, which is close to the high-strength aluminum magnesium silicon alloy (A2 type) wire. It can be used for a long time at 150 ℃, the current carrying capacity is 80-100% higher than that of ACSR, which significantly increases the line capacity. The current carrying capacity is higher than that of Al Mg Si alloy wire, which is 93.2%. At 150 ℃, the current carrying capacity is 127%, that is to say, the current carrying capacity can be increased by 1.27 times, which is an indispensable new line for high voltage and ultra-high voltage large crossing lines. There are also quite a number of heat-resistant aluminum alloy conductors used in power transmission lines in the United States, Canada and France, and the usage in Southeast Asia is also increasing by a large margin.
As we all know, the transmission lines from the southwest provinces and the Three Gorges to Guangdong all need to pass through high mountains and valleys and heavy ice areas in Guizhou, Hunan, Yunnan and other provinces. In order to build transmission lines with excellent performance in these areas, it is obviously not enough and unreasonable to use only steel cored aluminum stranded wires for conductors. After repeated demonstration by experts, ACSR will be the most important new type of wire, which will be used in these projects. So many long-distance, ultra-high voltage transmission lines need to be built in a short time, which provides a new and most important development opportunity for the aluminum alloy conductor manufacturers in China.
