Aluminum conductor for overhead conductor

Abstract

The invention relates to improvement to an aluminium conductor used for overhead leads, which is characterized in that: during electrical aluminium ingot melting, according to the content of silicon, heavy metal and iron in the raw material, lanthanum-rich rare earth aluminium alloy, boron or aluminium boron alloy, iron or aluminium iron alloy are respectively added or not added into the raw material; the weight percentage of silicon in the aluminium is controlled to be not more than 0.05wt%, the weight percentage of heavy metal in the aluminium is controlled to be not more than 0.01wt% and the weight percentage of iron in the aluminium is controlled to be between 0.12-0.16wt%; according to wire drawing, the aluminium conductor with the resistivity of 27.300-27.650n Omega question mark m and the tensile strength of 160-200MPa is obtained. Therefore, not only the tensile strength of the hard aluminium conductor is kept, but also the conductivity of the aluminium conductor is improved; the main technical index is obviously better than that of the hard aluminium conductor of national standard GB / T17048-1997; the aluminium conductor of the invention is used for the overhead leads and can obviously improve the high-carrying flux.

Description

technical field [0001] The invention is an improvement to the aluminum conductor for overhead wires, in particular to an aluminum conductor for overhead wires with high electrical conductivity and high tensile strength. Background technique [0002] The existing aluminum conductors for power transmission overhead wires are mainly smelted from aluminum for electrical purposes, and then rolled into aluminum rods at about 500°C, and then drawn. It is 61% IACS, and the tensile strength is 160-200Mpa (monofilament diameter 5-1.25mm). Chemical composition of aluminum for electrical purposes (GB / T3954-2001): Si≤0.11, Fe≤0.25, Cu≤0.01, total content of heavy metals (V+Ti+Mn+Cr)≤0.02, Al≥99.6. According to data, the conductivity of the conductor is 61% IACS, the loss of the power grid reaches more than 8.9% of the transmitted electricity, and it can reach 20% when the local power grid is poor. If the resistivity of the aluminum conductor is reduced, the current carrying capacity of...

AI Technical Summary

Problems solved by technology

Still due to the existence of annealing process, the tensile strength of the obtained conductor drops greatly, which is only slightly higher than that of the soft aluminum conductor, and it is also not suitable for large-span overhead conductors

[0007] The high-strength heat-resistant aluminum alloy wire disclosed in Chinese patent CN101074465 selects standard aluminum ingots with a purity of 99.7%, and the content of impurities other than silicon, iron, and copper does not exceed 0.02% by weight. The strength of the conductor is improved by adding alloy elements, and the tensile strength is as high as 225Mpa, but the conductivity of the conductor is greatly reduced, the conductivity is only 55% IACS, and the long-term heat resistance temperature is 150°C

[0008] It can be seen from the above prior art that by adding some alloy elements and annealing at the same time, the resistivity of the aluminum conductor can be reduced, but at the same time the tensile strength of the obtained aluminum conductor is also reduced, and its tensile strength is only slightly higher than that of the soft aluminum conductor , the resulting aluminum conductor is still unsuitable for large-span overhead conductors

At the same time, the existing technology gives enlightenment: the change of one performance of the aluminum conductor will affect the other performance, for example, the conductivity increases, but the strength decreases; the heat resistance level increases, but the conductivity does not increase; the conductor strength increases, but the conductivity decreases

Therefore improve the electrical conductivity of aluminum conductor at the same time, and keep the high level of duralumin again in tensile strength, it is very difficult, none of the prior art can realize reducing the resistivity of conductor at the same time, and can keep the high tensile strength of conductor (Table 1). 1)

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