An overhead conductor for coastal areas and a method for manufacturing the same

Abstract

The application discloses an overhead conductor for coastal areas and a preparation method thereof, and belongs to the field of wire and cable manufacturing, and comprises a composite steel core and an aluminum alloy strand twisted on the composite steel core, wherein the composite steel core comprises a steel inner core and a cladding layer, the cladding layer comprises an aluminum alloy layer and a low-aluminum layer containing nickel, the low-aluminum layer containing nickel is coated outside the steel inner core, and the aluminum alloy layer is coated outside the low-aluminum layer containing nickel, so as to form a gradient structure of the steel inner core / low-aluminum layer containing nickel / aluminum alloy layer / aluminum alloy strand. The application is particularly suitable for coastal areas.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wire and cable manufacturing, in particular to an overhead conductor for coastal areas and a preparation method thereof. BACKGROUND

[0002] At present, the overhead conductor used in the overhead transmission line in China is basically the traditional steel-cored aluminum stranded conductor. In order to prevent the corrosion of the steel, a layer of zinc is usually hot-dipped on the surface of the steel core. The steel-cored aluminum stranded conductor is prepared by twisting the treated aluminum wires that meet the requirements on the treated steel core that has been hot-dipped with zinc. The aluminum wires can be multiple and twisted in one or two layers on the surface of the steel core.

[0003] With the development of modern science and technology, higher and higher requirements are brought to the overhead conductor. The traditional steel-cored aluminum stranded conductor cannot meet the development of modern science and technology in terms of power transmission capacity, weather resistance and other aspects. Therefore, technical improvement of the overhead conductor is urgently needed.

[0004] In the technical improvement, the overhead conductor using aluminum alloy conductor instead of aluminum wire appears, but there is no inner core suitable for the environment in coastal areas matched with the aluminum alloy stranded conductor.

[0005] The above background is for the convenience of understanding the present application, and is not the known technology publicly known to the public before the present application. SUMMARY

[0006] In view of the above defects, the present application provides a kind of, it aims at improving at least one problem mentioned in the background art.

[0007] The technical scheme is: an overhead conductor for coastal areas, comprising a composite steel core and an aluminum alloy stranded conductor twisted on the composite steel core, the composite steel core comprises a steel inner core and a cladding layer, the cladding layer comprises an aluminum alloy layer and a low-aluminum layer containing nickel, the low-aluminum layer containing nickel is cladded outside the steel inner core, and the aluminum alloy layer is cladded outside the low-aluminum layer containing nickel, forming a gradient structure of steel inner core / low-aluminum layer containing nickel / aluminum alloy layer / aluminum alloy stranded conductor.

[0008] Further, the steel inner core is a steel bar.

[0009] Further, the steel bar is 304 stainless steel with a diameter of 2.5 mm.

[0010] Further, the thickness of the low-aluminum layer containing nickel is 25-35 μm, the thickness of the aluminum alloy layer is 55-65 μm, and the sum of the thickness of the low-aluminum layer containing nickel and the thickness of the aluminum alloy layer is 80-100 μm.

[0011] Further, the thickness of the low-aluminum layer containing nickel is 30 μm, and the thickness of the aluminum alloy layer is 60 μm.

[0012] The application also provides a preparation method of overhead conductor for coastal areas.

[0013] The technical scheme is as follows: A preparation method of overhead conductor for coastal areas, comprising the following steps:

[0014] S1, preparing a composite steel core, comprising the following steps:

[0015] S11, taking a steel bar, and pre-treating and drying and preheating the steel bar to 100-200 DEG C;

[0016] S12, hot-dipping the steel bar in a dipping pot, and the hot-dipping is performed twice, the first hot-dipping liquid is a low-aluminum nickel-containing melt, the component content of the low-aluminum nickel-containing melt is Ni 70%, Al 15%-25% and Si 5%-15%, the hot-dipping temperature is controlled to be 950-1050 DEG C, and the target thickness of the plating layer is 25-35 mu m; the second hot-dipping liquid is an aluminum alloy melt, the component content of the aluminum alloy melt is the same as that of the aluminum alloy single wire, the hot-dipping temperature is controlled to be 690-720 DEG C, and the target thickness of the plating layer is 55-65 mu m;

[0017] S13, taking out the hot-dipped steel bar, and post-treating;

[0018] S2, taking an aluminum alloy single wire;

[0019] S3, twisting the aluminum alloy single wire to the composite steel core.

[0020] Further, the diameter of the aluminum alloy single wire is 2.5 mm, and the component of the aluminum alloy single wire or the aluminum alloy melt is as follows: Fe 8.5%, V 1.3%, Si 1.7%, and the balance is Al.

[0021] Compared with the prior art, the application has the beneficial effects that:

[0022] The application first replaces the zinc hot-dipping with aluminum, increases the aluminum area, then replaces the aluminum melt hot-dipping with an aluminum alloy melt having the same component as the twisted wire, and then hot-dips the low-aluminum nickel-containing melt before hot-dipping the aluminum alloy under the condition that the total thickness of the hot-dipping layer is the same.

[0023] When the steel bar coated with the low-aluminum nickel-containing inner layer and the aluminum alloy outer layer is matched with the aluminum alloy twisted wire to be used as the overhead conductor, a gradient structure of iron (steel inner core) / low-aluminum nickel-containing layer / aluminum alloy / aluminum alloy twisted wire is formed, the steel core and the aluminum alloy twisted wire are matched with each other, the salt spray effect is unexpected, and the application is particularly suitable for the coastal areas. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic diagram of a cross section of the overhead conductor of the application;

[0025] In the diagram, 1 is a composite steel core, and 2 is an aluminum alloy stranded wire. Detailed Implementation

[0026] As used in this article:

[0027] "Prepared from" is synonymous with "comprising". The terms "comprising", "including", "having", "containing", or any other variations thereof as used herein are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be construed as limiting the scope of this application. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0030] In these embodiments, unless otherwise specified, the portions and percentages are all by weight.

[0031] "Parts by mass" refers to the basic unit of measurement that expresses the mass ratio of multiple components. One part can represent any unit mass, such as 1g or 2.689g. If we say that component A has "a" parts by mass and component B has "b" parts by mass, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it can mean that the mass of component A is aK and the mass of component B is bK (K is any number representing a multiplier). It is important to understand that, unlike the number of parts by mass, the sum of the mass parts of all components is not limited to 100 parts.

[0032] "And / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0033] In this invention, the neutral salt spray test method is as follows:

[0034] Test temperature: 35℃±2℃

[0035] 80 cm 2Average sedimentation rate of horizontal area: 1.5 ml / h ± 0.5 ml / h

[0036] Concentration of sodium chloride solution (collection solution): 50 g / L ± 5 g / L

[0037] PH value (collection solution): 6.5~7.2 (25℃±2℃)

[0038] Spray pressure: 98 kPa

[0039] Saturated tower hot water temperature: 48℃

[0040] Test period: 720h

[0041] In the present application, the transmission capacity is calculated according to the value of the ampacity detected by the DL / T 1935-2018 overhead conductor ampacity test method.

[0042] Comparative Example 1

[0043] Please refer to Figure 1 , Figure 1 is a schematic diagram of the cross section of the overhead conductor of the present application.

[0044] An overhead conductor for coastal areas, comprising a composite steel core 1 and an aluminum alloy strand 2 twisted on the composite steel core 1, the overhead conductor for coastal areas is made by the following steps:

[0045] S1, preparing a composite steel core 1, comprising the following steps:

[0046] S11, taking a 304 stainless steel rod (hereinafter referred to as steel rod) with a diameter of 2.5 mm, pretreating the steel rod and drying and preheating to about 150℃.

[0047] S12, placing the steel rod into a hot dip pot for hot dipping, the hot dip solution is an aluminum melt, the aluminum content in the aluminum melt is >= 99.8%, the hot dipping temperature is controlled at about 700℃, and the target thickness of the plating layer is 90μm.

[0048] S13, taking out the steel rod with aluminum layer after hot dipping and post-treating.

[0049] S2, taking an aluminum alloy monofilament, the aluminum alloy monofilament has a diameter of 2.5 mm, and the composition of the aluminum alloy monofilament is: Fe 8.5%, V 1.3%, Si 1.7%, and the balance is Al.

[0050] S3, twisting the aluminum alloy monofilament onto the composite steel core 1 formed by the aluminum layer steel rod group to form an aluminum alloy strand 2.

[0051] The product of the present embodiment was subjected to ampacity test and neutral salt spray test respectively, and the results are shown in Table 1 below.

[0052] Comparative Example 2

[0053] Compared with Comparative Example 1, the difference is that in S12, the hot dipping liquid is an aluminum alloy melt, and the component content of the aluminum alloy melt is the same as that of the aluminum alloy single wire.

[0054] The products of the present example were respectively subjected to current carrying capacity test and neutral salt spray test, and the results are shown in Table 1 below.

[0055] Comparative Example 3

[0056] Compared with Comparative Example 1, the difference is that in S12, the hot dipping liquid is a low-aluminum melt containing nickel, the component content of the low-aluminum melt containing nickel is Ni 70%, Al 20%, and Si 10%, and the hot dipping temperature is controlled at about 700°C.

[0057] The products of the present example were respectively subjected to current carrying capacity test and neutral salt spray test, and the results are shown in Table 1 below.

[0058] Example 1

[0059] Compared with Comparative Example 3, the difference is that in S12, the hot dipping is twice, the first hot dipping liquid is a low-aluminum melt containing nickel, the component content of the low-aluminum melt containing nickel is Ni 70%, Al 20%, and Si 10%, the hot dipping temperature is controlled at about 1000°C, and the target thickness of the plating layer is 30μm. The second hot dipping liquid is an aluminum alloy melt, the component content of the aluminum alloy melt is the same as that of the aluminum alloy single wire, the hot dipping temperature is controlled at about 700°C, and the target thickness of the plating layer is 60μm.

[0060] The products of the present example were respectively subjected to current carrying capacity test and neutral salt spray test, and the results are shown in Table 1 below.

[0061] Example 2

[0062] Compared with Example 1, the difference is that in S12, the component content of the low-aluminum melt containing nickel is Ni 70%, Al 22%, and Si 8%.

[0063] The products of the present example were respectively subjected to current carrying capacity test and neutral salt spray test, and the results are shown in Table 1 below.

[0064] Example 3

[0065] Compared with Example 1, the difference is that in S12, the component content of the low-aluminum melt containing nickel is Ni 70%, Al 18%, and Si 12%.

[0066] The products of the present example were respectively subjected to current carrying capacity test and neutral salt spray test, and the results are shown in Table 1 below.

[0067] Comparative Example 4

[0068] Compared with the comparative example 1, the difference is that in S12, the hot dipping solution is zinc melt, the zinc content in the zinc melt is ≥99.95%, and the hot dipping temperature is controlled at about 450℃.

[0069] The products of the present comparative example were respectively subjected to current carrying capacity test and neutral salt spray test, and the results are shown in Table 1.

[0070] Table 1

[0071]

[0072] Note:

[0073] In Table 1, the number of steel rods of the test sample is 7, and the number of aluminum alloy filaments is 45. Among the 7 steel rods, one is in the center, and the other six are arranged around the center rod and coated inside. The 45 aluminum alloy filaments are twisted in two layers on the steel rod group formed by the 7 steel rods, and the filling rate is 92%.

[0074] In Table 1, the transmission capacity ratio is based on the transmission capacity value of the comparative example 4. The ratio of the transmission capacity value of the other examples divided by the transmission capacity value of the comparative example 4 is the transmission capacity ratio. The salt spray test ratio is based on the corrosion area of the comparative example 4. The ratio of the corrosion area of the other examples divided by the corrosion area of the comparative example 4 is the salt spray test ratio.

[0075] As can be seen from Table 1, compared with the existing galvanized aluminum alloy stranded wire with steel core (comparative example 4), the systems of the present application are better than the existing ones in neutral salt spray effect while maintaining at least the transmission capacity. Among them, the adaptability of example 2 is the best, and the system of example 2 realizes the best matching of aluminum alloy stranded wire and stainless steel core.

Claims

1. An overhead conductor for coastal areas comprising a composite steel core and an aluminum alloy strand stranded on the composite steel core, the composite steel core comprising a steel inner core and a cladding layer, characterized in that, The cladding layer comprises an aluminum alloy layer and a low-aluminum layer containing nickel, the low-aluminum layer containing nickel is cladded outside the steel inner core, the aluminum alloy layer is cladded outside the low-aluminum layer containing nickel, forming a gradient structure of steel inner core / low-aluminum layer containing nickel / aluminum alloy layer / aluminum alloy wire; The overhead conductor for coastal areas is prepared by the following method: S1, preparing a composite steel core, comprising the following steps: S11, taking a steel bar, and pre-treating and drying and preheating the steel bar to 100-200 DEG C; S12, placing the steel bar into a hot dipping pot for hot dipping, the hot dipping is performed twice, the first hot dipping liquid is a low-aluminum melt containing nickel, the component content of the low-aluminum melt containing nickel is Ni 70%, Al 15%-25%, Si 5%-15%, and the hot dipping temperature is controlled to be 950-1050 DEG C; the second hot dipping liquid is an aluminum alloy melt, the component content of the aluminum alloy melt is the same as that of the aluminum alloy single wire, and the hot dipping temperature is controlled to be 690-720 DEG C; S13, taking out the steel bar after hot dipping, and post-treating; S2, taking an aluminum alloy single wire; S3, twisting the aluminum alloy single wire onto the composite steel core; The aluminum alloy single wire has a diameter of 2.5 mm, and the aluminum alloy single wire or the aluminum alloy melt has the following components: Fe 8.5%, V 1.3%, Si 1.7%, and the balance being Al.

2. The overhead conductor for coastal areas according to claim 1, characterized in that, The steel inner core is a steel bar.

3. The overhead conductor for coastal areas according to claim 2, characterized in that, The steel bar is 304 stainless steel, and has a diameter of 2.5 mm.

4. The overhead conductor for coastal areas according to claim 1, characterized in that, The low-aluminum layer containing nickel has a thickness of 25-35 μm, the aluminum alloy layer has a thickness of 55-65 μm, and the sum of the thickness of the low-aluminum layer containing nickel and the thickness of the aluminum alloy layer is 80-100 μm.

5. The overhead conductor for coastal areas according to claim 1, characterized in that, The low-aluminum layer containing nickel has a thickness of 30 μm, and the aluminum alloy layer has a thickness of 60 μm.

6. A method for preparing an overhead conductor for coastal areas, characterized in that, comprising the following steps: S1, preparing a composite steel core, comprising the following steps: S11, taking a steel bar, and pre-treating and drying and preheating the steel bar to 100-200 DEG C; S12, placing the steel bar into a hot dipping pot for hot dipping, the hot dipping is performed twice, the first hot dipping liquid is a low-aluminum melt containing nickel, the component content of the low-aluminum melt containing nickel is Ni 70%, Al 15%-25%, Si 5%-15%, and the hot dipping temperature is controlled to be 950-1050 DEG C, and the target thickness of the coating is 25-35 μm; the second hot dipping liquid is an aluminum alloy melt, the component content of the aluminum alloy melt is the same as that of the aluminum alloy single wire, the hot dipping temperature is controlled to be 690-720 DEG C, and the target thickness of the coating is 55-65 μm; S13, taking out the steel bar after hot dipping, and post-treating; S2, taking an aluminum alloy single wire; S3, twisting the aluminum alloy single wire onto the composite steel core.

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