Capacity-increasing conductor formed by twisting super-strong steel core and semi-hard aluminum wire and manufacturing method

Abstract

The present invention provides a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire, including a wire core and an aluminum wire, wherein the aluminum wire is tightly wrapped around the outside of the wire core, the wire core adopts a super-strong steel core with super high strength, and the aluminum wire is a semi-hard aluminum wire. Manufacturing method: aluminum rod processing; aluminum wire drawing; aluminum wire annealing to a semi-hard state; twisting the super-strong steel core and the semi-hard aluminum wire into a conductor. The capacity-increasing conductor of the present invention has the advantages of good electrical conductivity, can be applied to high-temperature operation, can increase the line transmission capacity by 50% to 100%, and has good sag characteristics; at the same time, due to the improvement of the strength of the aluminum single wire, it has the advantages of convenient construction, wear resistance, and not easy to bulge, thereby ensuring the safe operation of the line.

Description

Technical Field

[0001] The invention relates to the technical field of power transmission lines, and in particular to a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire, and a manufacturing method thereof. Background Art

[0002] Traditional power transmission lines are generally based on steel core aluminum stranded wires, with the core made of ordinary strength galvanized steel stranded wires and the outer layer made of electrical hard round aluminum wires. The operating temperature of this structure of conductors is generally 80℃ or below, and the transmission capacity is relatively small. The commonly used soft aluminum type capacity-increasing conductors are easy to scratch due to the low strength of the aluminum wires, especially in places with harsh terrain, corners and large drops, the soft aluminum conductors are prone to bulging. Summary of the invention

[0003] In order to solve the above defects, the purpose of the present invention is to provide a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire, which has the advantages of greatly improving the transmission capacity, good sag characteristics, convenient construction, wear resistance and not easy to bulge.

[0004] Another object of the present invention is to provide a method for preparing the capacity-enhanced conductor formed by twisting the extra-strong steel core and the semi-hard aluminum wire.

[0005] To achieve the above-mentioned purpose, the present invention provides a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire, comprising a wire core and an aluminum wire, wherein the aluminum wire is tightly wrapped around the outside of the wire core, the wire core adopts a super-strong steel core with super high strength, and the aluminum wire is a semi-hard aluminum wire; the shape of the semi-hard aluminum wire is T or SZ type, and the number of layers of the semi-hard aluminum wire is one layer, two layers, three layers or four layers.

[0006] Furthermore, the strength of the extra-strong steel core is ≥1770 MPa, the strength of the semi-hard aluminum profile is 90-140 MPa, the resistivity is ≤27.37 nΩ·m, and the elongation is ≥4.0%.

[0007] A method for manufacturing a capacity-enhanced conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire comprises the following steps:

[0008] 1) Aluminum rod processing: Select high-quality electrical aluminum ingots for melting, aluminum liquid insulation and static composition ratio, casting, and rolling into aluminum rods;

[0009] 2) Aluminum profile wire drawing: The aluminum rod is processed into an aluminum profile wire of a desired cross-section by a profile wire drawing machine, and during the wire drawing process, the elongation coefficient of each pass of the wire drawing die is controlled between 1.15 and 1.35.

[0010] 3) Annealing of the aluminum profile wire to a semi-hard state: The drawn aluminum profile wire is placed in a box-type annealing furnace for annealing at a temperature of 230-280°C for 4-7 hours.

[0011] 4) Extra-strong steel core and semi-hard aluminum wire are twisted into conductors: The extra-strong steel core and semi-hard aluminum wire are twisted by a frame-type twisting machine. The wires are pre-twisted during twisting to ensure the quality and tightness of the twisting.

[0012] Furthermore, in the step 1), the aluminum rod is selected from an aluminum ingot with an aluminum content of not less than 99.75%, Si≤0.08%, Fe≤0.18%, Cu≤0.005%, and four small elements Ti+Cr+Mn+V≤0.015%, and is melted, the aluminum liquid is kept still to form a proportion, cast, and rolled into an aluminum rod in sequence; the diameter of the aluminum rod is 9.5mm or 12mm, the diameter of the aluminum rod is 9.5mm or 12mm, the tensile strength of the aluminum rod is 95~115MPa, the resistivity of the aluminum rod is ≤27.70nΩ·m, and the elongation of the aluminum rod is ≥11%.

[0013] Furthermore, in the step 2), the tensile strength of the aluminum profile wire is ≤170 MPa, and the resistivity is ≤27.85 nΩ·m.

[0014] Furthermore, in the step 3), the tensile strength of the semi-hard aluminum profile after annealing is 95-140 MPa, the resistivity is ≤27.37 nΩ·m, the elongation is ≥5.0%, and the heat resistance strength retention rate at 230°C for one hour should be no less than 90% of the initial measured value at room temperature.

[0015] Furthermore, in the step 4), the strength of the extra-strong steel core is ≥1770Mpa, the strength of the semi-hard aluminum wire after twisting is 90~140Mpa, the resistivity is ≤27.37nΩ·m, the elongation is ≥4.0%, and the heat resistance strength retention rate at 230°C for one hour should be no less than 90% of the initial measured value at room temperature.

[0016] Beneficial effects of the present invention: The capacity-increasing conductor of the present invention has the advantages of good conductivity, can be applied to high-temperature operation, can increase the line transmission capacity by 50% to 100%, and has good sag characteristics. At the same time, since the strength of the super-strong steel core reaches 95 to 140Mpa, it can effectively improve the strength of the aluminum single wire, has the advantages of convenient construction, wear resistance and not easy to bulge, and ensures the safe operation of the line. The strength of the steel core is conducive to improving the overall breaking force of the conductor, ensuring the safe operation of the line, and since the strength of the aluminum wire is reduced compared to ordinary conductors, improving the strength of the steel core can make the breaking force of this product similar to that of ordinary products, and has better substitutability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of Example 1 of the present invention.

[0018] Figure 2This is a structural schematic diagram of Example 2 of the present invention.

[0019] Among them: 1. Wire core, 2. Aluminum wire. DETAILED DESCRIPTION

[0020] The present patent is further described below in conjunction with the accompanying drawings and specific embodiments, but the scope of protection of the present patent is not limited to the embodiments described below. For technical personnel in this technical field, under the inspiration of the present patent, they can directly derive or associate some basic variations with the same principles from the disclosure of the present patent, or replace commonly used well-known technologies in the prior art, as well as different combinations of features, and simple replacement of technical features with the same or similar technical effects, all of which fall within the scope of protection of the present patent.

[0021] Embodiment 1:

[0022] like Figure 1 As shown, a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire comprises a wire core 1 and an aluminum wire 2. The aluminum wire 2 is tightly wrapped around the outer side of the wire core 1. The wire core adopts a super-strong steel core with super high strength, and the aluminum wire is a 2-layer T-shaped semi-hard aluminum wire conductor.

[0023] Among them, the strength of the super-strong steel core is ≥1770Mpa, the strength of the semi-hard aluminum wire is 90~140Mpa, the resistivity is ≤27.37nΩ·m, and the elongation is ≥4.0%.

[0024] Embodiment 2:

[0025] like Figure 2 As shown, a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire comprises a wire core 1 and an aluminum wire 2. The aluminum wire 2 is tightly wrapped around the outer side of the wire core 1. The wire core adopts a super-strong steel core with super high strength, and the aluminum wire is a 2-layer SZ-type semi-hard aluminum wire conductor.

[0026] Among them, the strength of the super-strong steel core is ≥1770Mpa, the strength of the semi-hard aluminum wire is 90~140Mpa, the resistivity is ≤27.37nΩ·m, and the elongation is ≥4.0%.

[0027] A method for manufacturing a capacity-enhanced conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire comprises the following steps:

[0028] 1) Aluminum rod processing: Select high-quality electrical aluminum ingots for melting, aluminum liquid insulation and static composition ratio, casting, and rolling into aluminum rods;

[0029] 2) Aluminum profile wire drawing: The aluminum rod is processed into an aluminum profile wire of a desired cross-section by a profile wire drawing machine, and during the wire drawing process, the elongation coefficient of each pass of the wire drawing die is controlled between 1.15 and 1.35.

[0030] 3) Annealing of the aluminum profile wire to a semi-hard state: The drawn aluminum profile wire is placed in a box-type annealing furnace for annealing at a temperature of 230-280°C for 4-7 hours.

[0031] 4) Extra-strong steel core and semi-hard aluminum wire are twisted into conductors: The extra-strong steel core and semi-hard aluminum wire are twisted by a frame-type twisting machine. The wires are pre-twisted during twisting to ensure the quality and tightness of the twisting.

[0032] In the step 1), the aluminum rod is selected from an aluminum ingot with an aluminum content of not less than 99.75%, Si≤0.08%, Fe≤0.18%, Cu≤0.005%, and four small elements Ti+Cr+Mn+V≤0.015%, and is melted, the aluminum liquid is kept still to form a proportion, cast, and rolled into an aluminum rod in sequence; the diameter of the aluminum rod is 9.5 mm or 12 mm, the diameter of the aluminum rod is 9.5 mm or 12 mm, the tensile strength of the aluminum rod is 95-115 MPa, the resistivity of the aluminum rod is ≤27.70 nΩ·m, and the elongation of the aluminum rod is ≥11%.

[0033] In the step 2), the tensile strength of the aluminum profile wire is ≤170 MPa, and the resistivity is ≤27.85 nΩ·m.

[0034] In the step 3), the tensile strength of the semi-hard aluminum profile after annealing is 95-140 MPa, the resistivity is ≤27.37 nΩ·m, the elongation is ≥5.0%, and the heat resistance strength retention rate at 230°C for one hour should be no less than 90% of the initial measured value at room temperature.

[0035] In the step 4), the strength of the extra-strong steel core is ≥1770Mpa, the strength of the semi-hard aluminum profile wire after twisting is 90~140Mpa, the resistivity is ≤27.37nΩ·m, the elongation is ≥4.0%, and the heat resistance strength retention rate at 230°C for one hour should be no less than 90% of the initial measured value at room temperature.

[0036] Example 1 is produced by the above preparation method. Among them, an aluminum ingot with an excellent aluminum content greater than 99.75% is used to produce an aluminum rod with a diameter of 9.5mm, a strength of 100MPa, a resistivity of 27.65nΩ·m, and an elongation of 13.5%. Then, the aluminum wire strength of 150MPa and a resistivity of 27.80nΩ·m are produced by wire drawing. The aluminum single wire is annealed at an annealing temperature of 255℃ for 5.5 hours. After annealing, the aluminum wire has a resistivity of 27.32nΩ·m (conductivity 63.1%IACS), a strength of 105MPa, an elongation of 8.0%, and a strength retention rate (230℃ for 1 hour) of 95%. Finally, a super-strong steel core with a steel wire strength of 1850MPa is selected to be twisted with the above-mentioned annealed aluminum wire. The test results show that the strength of the twisted capacitated conductor is 103MPa, the elongation is 7.5%, the resistivity is 27.32nΩ·m (conductivity is 63.1%IACS), and the strength retention rate (230℃ for 1 hour) is 96%.

[0037] The present invention adopts a semi-hard aluminum conductor material that can operate at high temperatures, is suitable for high-temperature operation, has good conductivity, can increase the line transmission capacity by 50% to 100%, has good sag characteristics, etc.; at the same time, due to the improved strength of the aluminum single wire, it has the advantages of convenient construction, wear resistance and not easy to bulge, etc., thereby ensuring the safe operation of the line.

Claims

1. The capacity-increasing conductor is made of a super-strong steel core and a semi-hard aluminum wire, and is characterized by: It comprises a wire core and an aluminum wire, wherein the aluminum wire is tightly wrapped around the outer side of the wire core, the wire core adopts an ultra-high strength steel core, and the aluminum wire is a semi-hard aluminum wire; the shape of the semi-hard aluminum wire is T or SZ type, and the number of layers of the semi-hard aluminum wire is one layer, two layers, three layers or four layers; A method for manufacturing a capacity-increasing conductor formed by twisting a super-strong steel core and a semi-hard aluminum wire comprises the following steps: 1) Aluminum rod processing: select electrical aluminum ingots for melting, aluminum liquid insulation and static distribution, casting, and rolling into aluminum rods; 2) Aluminum profile wire drawing: The aluminum rod is processed into an aluminum profile wire of a desired cross section by a profile wire drawing machine, and during the wire drawing process, the elongation coefficient of each pass of the wire drawing die is controlled between 1.15 and 1.35; 3) Annealing of aluminum profile wire to semi-hard state: The aluminum profile wire after drawing is placed in a box-type annealing furnace for annealing treatment. The annealing temperature is 230~280℃ and the annealing time is 4~7 hours; 4) Extra-strong steel core and semi-hard aluminum profile wire are twisted into conductors: The extra-strong steel core and semi-hard aluminum profile wire are twisted by a frame-type twisting machine, and the profile wire is pre-twisted during twisting to ensure the quality and tightness of the twisting; In the step 1), the aluminum rod is selected from aluminum ingots with an aluminum content of not less than 99.75%, Si≤0.08%, Fe≤0.18%, Cu≤0.005%, and four small elements Ti+Cr+Mn+V≤0.015%, and is sequentially melted, the aluminum liquid is kept still to form a proportion, cast, and rolled into an aluminum rod; the diameter of the aluminum rod is 9.5 mm or 12 mm, the tensile strength of the aluminum rod is 95-115 MPa, the resistivity of the aluminum rod is ≤27.70 nΩ·m, and the elongation of the aluminum rod is ≥11%; In the step 2), the tensile strength of the aluminum profile wire is ≤170 MPa, and the resistivity is ≤27.85 nΩ·m; In the step 3), after annealing, the tensile strength of the semi-hard aluminum profile wire is 95-140 MPa, the resistivity is ≤27.37 nΩ·m, the elongation is ≥5.0%, and the strength retention rate at 230°C for one hour is not less than 90% of the initial measured value at room temperature; In the step 4), the strength of the extra-strong steel core is ≥1770Mpa, the tensile strength of the semi-hard aluminum profile wire after twisting is 90~140Mpa, the resistivity is ≤27.37nΩ·m, the elongation is ≥4.0%, and the heat resistance strength retention rate at 230°C for one hour is not less than 90% of the initial measured value at room temperature.

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