JP2001023436A - Power transmission cable with high anti-corrosiveness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission cable with a high anti-corrosiveness serviceable without applying special anti-corrosive processing in a highly corrosive environment in which water containing chlorine ions, etc., exists. SOLUTION: The strand of a power transmission cable with high anti- corrosiveness consists of conductive element wires as an anti-corrosive aluminum alloy wire 11 for electric conduction having such a composition as containing 0.3-4.3 wt.% Mn with the remainder being Al and inevitable impurities where an inter-metal compound of Al-Mn series is dispersively deposited or an anti-corrosive aluminum alloy wire 11 for electric conduction having such a composition as containing 0.3-4.3 wt.% Mn and 0.05-6.0 wt.% Mg with the remainder being Al and inevitable impurities where an inter-metal compound of Al-Mn series is dispersively deposited or a composite wire formed by covering the alloys.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission line such as an overhead transmission line or a railway feeder line installed between steel towers, and more particularly to an environment in which a highly corrosive substance such as chlorine ion is present. The present invention relates to a transmission line having high corrosion resistance.

[0002]

2. Description of the Related Art Overhead transmission lines and railway feeder lines installed between steel towers are required to be lightweight in order to reduce the construction costs of the steel towers and other facilities. For this reason, a conductor element made of aluminum or an aluminum alloy, which is lightweight and has relatively high conductivity among conductors, is used as the conductor element of an overhead transmission line or a railway feeder line.

[0003] By the way, such overhead power lines and electric wires for electric trains are exposed to natural environments such as sunlight, wind and rain, and snow, and are required to have excellent environmental resistance.
Aluminum or aluminum alloy wires used as stranded conductor strands have relatively good corrosion resistance in such ordinary natural environments and are therefore used without any anticorrosion treatment.

[0004]

However, such an aluminum or aluminum alloy wire having excellent corrosion resistance is also used in a region close to the ocean because a large amount of steam containing salt in the seawater is present in the atmosphere. There is a problem that corrosion progresses due to ions and the like, and the life of the electric wire is significantly reduced. Furthermore, in areas other than those near the ocean, in recent years, corrosion of aluminum and aluminum alloy wires has progressed due to rainwater in which air pollutants such as sulfur oxides and nitrogen oxides, which are substances that cause acid rain, are dissolved. However, there is a problem that corrosion is further promoted due to heat generation or the like due to a decrease in conductivity, thereby causing disconnection.

Therefore, overhead transmission lines and the like used in areas exposed to such severe corrosive environments are:
Although anticorrosion measures such as applying grease to the metal surface have been taken, grease has a problem that it deteriorates in an atmospheric environment. That is, since the grease is composed of a polymer compound, there is a problem that the grease is degraded by ultraviolet rays or heat by sunlight, cracks or the like, peels off, and loses corrosion resistance. For this reason, it is necessary to periodically monitor the anticorrosion overhead transmission lines that have been subjected to anticorrosion treatment using grease according to the environment in which they are laid, and perform maintenance inspections such as replenishment of grease, In the case of cracking as described above, a corrosive aqueous solution penetrates through cracked gaps, and corrosion progresses rapidly in parts that cannot be observed from the appearance, so that there is a problem that complete maintenance management becomes difficult. . Further, there is a problem that the connection operation becomes troublesome when replacing the electric wire using such grease.

[0006] The present invention has been made in view of the above problems, and dissolves corrosive substances such as sulfur oxides and nitrogen oxides which cause chlorine-containing water and acid rain in marine areas. It is an object of the present invention to provide a high corrosion-resistant transmission line that does not need to be subjected to anticorrosion treatment using grease when exposed to corrosive environments such as rainwater.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive experiments and researches to solve the above-mentioned problems.
High conductivity and anti-corrosion treatment as described above are required by using an alloy wire or a composite wire that uses an aluminum alloy in which n-type intermetallic compounds are dispersed and deposited as a wire or coating material as a conductor wire of a stranded wire. The present inventors have found that a transmission line having extremely excellent corrosion resistance can be obtained in a highly corrosive environment in which water containing chlorine ions exists, and have reached the present invention.

That is, in the high corrosion-resistant transmission line according to the first aspect of the present invention, the conductor strand constituting the stranded wire has Mn of 0.3 to 4.
It is characterized by comprising a high corrosion-resistant aluminum alloy wire having a composition of 3% by weight, the balance being Al and unavoidable impurities, and an Al-Mn intermetallic compound dispersed and precipitated. .

Further, in the high corrosion resistant transmission line according to the present invention, the conductor element wire constituting the stranded wire contains Mn of 0.3 to 4.3% by weight, Mg
From 0.05 to 6.0% by weight, the balance being Al and inevitable impurities, and a high corrosion-resistant aluminum alloy wire in which Al-Mn intermetallic compounds are dispersed and precipitated. It is characterized by the following.

Further, in the high corrosion resistant transmission line according to the third aspect, the conductor strand constituting the stranded wire contains 0.3 to 4.3% by weight of Mn in a core material of conductive aluminum or conductive aluminum alloy. And a high corrosion-resistant composite wire coated with an aluminum alloy having a balance of Al and unavoidable impurities and coated with an Al-Mn intermetallic compound dispersedly deposited. It is.

Further, in the high corrosion-resistant transmission line according to the present invention, the conductor strand constituting the stranded wire is made of a conductive aluminum or a conductive aluminum alloy core material containing Mn of 0.3 to 4.3% by weight.
An aluminum alloy containing 0.05 to 6.0% by weight of Mg, the balance of which is composed of Al and unavoidable impurities, and in which Al-Mn intermetallic compounds are dispersed and deposited. It is characterized by being composed of a high corrosion resistant composite wire.

Further, in the high corrosion resistant transmission line according to the present invention, the conductor strand constituting the stranded wire is at least two or more selected from the high corrosion resistant alloy wire and the high corrosion resistant composite wire. It is characterized by including conductor strands.

[0013]

Embodiments of the present invention will be described below. As described in Means for Solving the Problems, the present invention provides a high corrosion-resistant aluminum alloy wire composed of an alloy obtained by heat-treating an aluminum alloy containing a specific amount of Mn and dispersing and depositing an Al-Mn intermetallic compound. In addition, a high corrosion-resistant composite wire obtained by coating an alloy obtained by dispersing and depositing such an Al-Mn intermetallic compound on aluminum for conductivity or an aluminum alloy wire for conductivity is used as a conductor wire of a stranded wire. It is a corrosion resistant transmission line. Here, an aluminum alloy used as a wire material or a coating material of a highly corrosion-resistant conductor strand will be described.
It is desirable that the intermetallic compound of the system be in a fine and uniform state. If the Al-Mn intermetallic compound is not sufficiently dispersed and precipitated, that is, if the concentration of Mn dissolved in aluminum is high, it is not possible to obtain a material having excellent corrosion resistance and conductivity. For the purpose of dispersing and precipitating in such a fine and uniform state, it is effective to add a predetermined amount of Mg.

When higher conductivity or heat resistance is required due to the environment in which the power transmission line is laid, etc., aluminum or aluminum alloy for conductivity is used as a core material, and an Al-Mn based material is used. By using a composite wire coated with the aluminum alloy in which the intermetallic compound is dispersed and deposited as a conductive strand, in addition to corrosion resistance, in properties such as conductivity, tensile strength, heat resistance, etc. Transmission lines can be obtained.

The coating rate of the coating layer in the composite wire can be appropriately selected and used according to the intended use. Usually, when high conductivity is required, the coating rate is 15 to 60 Vol%. Is preferable. If it is larger than 60% by volume, the desired effect of improving characteristics cannot be obtained.
If it is less than Vol%, the core material may be exposed during wire drawing or the like, and the desired corrosion resistance may not be obtained.

Here, the reasons for limiting the composition of the high corrosion-resistant aluminum alloy wire and the alloy used as the wire material or the coating material of the composite wire used as at least a part of the conductor wire constituting the stranded wire of the present invention will be described. Mn: Mn is an important alloy component for imparting corrosion resistance in the present invention, and precipitates as an Al-Mn intermetallic compound depending on the amount of Mn. If the added amount of Mn is more than 4.3% by weight, a coarse Mn compound is formed at the time of casting, and the subsequent processing becomes difficult, and the conductivity and the corrosion resistance are undesirably reduced. On the other hand, if the amount of Mn is less than 0.3% by weight, the amount of Al-Mn intermetallic compound precipitated and the state of dispersion are insufficient, and sufficient corrosion resistance cannot be obtained.

Mg: Mg is not necessarily an essential element in the present invention, but promotes the precipitation of an Al-Mn intermetallic compound. Contribute to gain. However, if the added amount of Mg is less than 0.05% by weight, such an effect cannot be sufficiently obtained, and if it exceeds 6.0% by weight, the conductivity, castability and workability are reduced. As 0.05 ~
It is preferably 6.0% by weight.

In addition to the above, it is preferable to add Ti in an amount of 0.003 to 0.2% by weight in order to refine the cast crystal structure. If the amount is less than 0.003% by weight, the intended effect cannot be obtained, and if it exceeds 0.2% by weight, a Ti-Al-based coarse intermetallic compound is generated. Ti and B or Ti
When C and C are added in combination, the refinement of the crystal is further promoted. When compounding Ti and B, Ti should be 0.003 ~
It is preferable to add 0.1 wt% and B at 0.0001 to 0.05 wt%. On the other hand, when Ti and C are added in combination, Ti is 0.003-0.1% by weight, and C is 0.0001-0.1%.
It is preferable to add 0.05% by weight.

To further improve the strength, Cr, V, Zr
Is desirably added in the range of 0.03 to 0.15% by weight, respectively. In order to prevent oxidation of the molten metal during casting, Be is added in an amount of 0.01% by weight.
It is desirable to contain less than.

Further, in the alloy used as the wire or the covering material of the highly corrosion-resistant conductor strand according to the present invention, the content of Fe is set to 0.1.
2 wt% or less, Si is 0.4 wt% or less, Zn is 0.5
The effect of the present invention is not substantially changed even if the content of impurity elements in the range of not more than 0.3% by weight and not more than 0.3% by weight of Cu.

As an example of a specific stranded structure of the high corrosion resistant transmission line of the present invention, as shown in FIG. 1, a high corrosion resistant transmission line in which an Al-Mn intermetallic compound is dispersed and precipitated as shown in FIG. A power transmission line formed only of a conductor element wire made of an aluminum alloy, or a twisted wire made of a galvanized steel wire 12 is arranged at a central portion as shown in FIG. 2, and a conductive aluminum wire is used as a core material around the stranded wire. An example is a transmission line in which a composite wire 13 coated with a high corrosion-resistant aluminum alloy is twisted as a conductor element wire. Although not shown, the conductor strands constituting the stranded wire are not only those having a round cross-section as shown, but also conductor elements having various known shapes such as a rectangular, trapezoidal, tape-shaped or pipe-shaped one. Needless to say, a stranded wire can be formed by using a wire.

[0022]

Next, the conductor strand used for the twisted wire of the present invention and the twisted wire obtained by twisting the same will be specifically described in comparison with a comparative example.

Example 1 Mn: 0.3% by weight, Fe: 0.1% by weight, Si: 0.
05% by weight, Zn: 0.05% by weight, Cu: 0.02% by weight, Ti: 0.02% by weight, Cr: 0.03% by weight,
V: 0.02% by weight, Zr: 0.02% by weight, balance Al
9.5mmφ by hot rolling
I got a rough line. Then, at 400 ° C in a reducing atmosphere,
After heat treatment for 2 hours, the wire was drawn by a continuous wire drawing machine to precipitate an Al-Mn intermetallic compound of 3.2 m.
An mφ aluminum alloy wire was obtained.

Example 2 An aluminum alloy having the same composition as in Example 1 was used except that Mn was changed to 1.6% by weight, and an Al—Mn intermetallic compound was precipitated in the same manner as in Example 1. .2mmφ
Was obtained.

Example 3 An aluminum alloy having the same composition as in Example 1 was used except that Mn was 4.3% by weight, and an Al—Mn intermetallic compound was precipitated in the same manner as in Example 1. .2mmφ
Was obtained.

Comparative Example 1 An Al-Mn intermetallic compound was precipitated in the same manner as in Example 1 except that an aluminum alloy having the same composition as in Example 1 was used except that Mn was 0.1% by weight. .2mmφ
Was obtained.

Comparative Example 2 An Al-Mn intermetallic compound was precipitated in the same manner as in Example 1 except that an aluminum alloy having the same composition as in Example 1 was used except that Mn was changed to 4.8% by weight. .2mmφ
Was obtained.

Example 4 A 9.5 mmφ rough wire having the same composition as in Example 1 was prepared except that 0.5% by weight of Mg was added, and then drawn and heat-treated in the same manner as in Example 1. And Al-M
A 3.2 mmφ aluminum alloy wire on which an n-type intermetallic compound was precipitated was obtained.

Example 5 An ingot having the same composition as in Example 2 was heat-treated in a reducing atmosphere at 400 ° C. for 10 hours, and then hot-rolled and cold-rolled to disperse the Al-Mn intermetallic compound. 1. Deposited thickness
An 8 mm aluminum alloy tape was obtained. Next, the tape is vertically attached to a 9.5 mmφ conductive aluminum core material, and the edge is welded while forming into a tubular shape, and a composite wire coated with an aluminum alloy on which an Al—Mn intermetallic compound is dispersed and deposited. I got Thereafter, the composite wire was drawn by a continuous wire drawing machine, and the coating material and the core material were completely integrated.
A 2 mmφ composite wire was obtained.

Example 6 An ingot having the same composition as in Example 2 was hot- and cold-rolled to produce a tape having a thickness of 0.9 mm. A composite wire of 0.2 mmφ was obtained.

Example 7 An ingot having the same composition as in Example 2 was hot- and cold-rolled to produce a tape having a thickness of 0.4 mm. A composite wire of 0.2 mmφ was obtained.

Conventional Example 1 A hard aluminum wire having a diameter of 3.2 mm was produced from an aluminum ingot for electric use specified in JIS H 2110.

Conventional Example 2 Si, Mg, etc. are added to an aluminum aluminum bar specified in JIS H 2110, and 3.2 mmφ specified in JEC-3405, a standard of the Institute of Electrical Engineers of Japan.
No. 1 aluminum alloy wire was manufactured.

Conventional example 3 A heat-resistant aluminum alloy wire of 3.2 mmφ defined by JEC-3406, a standard of the Institute of Electrical Engineers of Japan, was prepared by adding Zr and the like to aluminum metal for electrical use defined by JIS H 2110. .

Example 9 The aluminum alloy wire of Example 2 was drawn to 2.6 mmφ, and seven of them were twisted to produce a stranded wire.

Conventional Example 4 The aluminum wire of Conventional Example 1 was drawn to 2.6 mmφ,
Seven of these were twisted to produce a stranded wire.

Next, various characteristics were evaluated for the conductor wires and stranded wires of the examples, comparative examples, and conventional examples thus obtained. That is, Examples 1 to 8, Comparative Examples 1 and 2,
Conductivity and tensile strength of the conductor strands of Conventional Examples 1 to 3 were measured, and corrosion resistance was evaluated by performing a corrosion test. The stranded wires of Example 9 and Conventional Example 4 were only evaluated for corrosion resistance by a corrosion test. The corrosion resistance was evaluated by the following corrosion test. (1) 1 Corrosion tests 100mm length conductor wire and stranded wire was cut into an aqueous solution of 2N-HCl, respectively, to an aqueous solution of 2N-HNO ₃
After immersion for 00 hours, the corrosion loss after the test was measured. Next, the unit weight of the wire (c
The amount of corrosion (mg) per m ² ) was calculated. The test results are summarized in Tables 1 and 2.

[0038]

[Table 1]

[0039]

[Table 2]

As shown in Table 1, in the strands of Examples 1 to 7 used as the conductor strands constituting the stranded wire of the present invention, all the conductors have a high conductivity of 50% IACS or more. The corrosion rate in an aqueous solution containing highly corrosive chlorine ions in corrosion resistance is higher than that of the aluminum wires and alloy wires of Conventional Examples 1 to 3 which are currently used for conductivity. It has excellent corrosion resistance of about one-tenth, and about 1/2 of an oxidizing acid such as nitrate ion. Further, as shown in Examples 5 to 7, in the case where a composite wire is formed by using highly conductive aluminum for the core material, the conductive material required most often in the current aluminum-based conductor material is used. A conductor strand having a high conductivity of 55% IACS or more can be obtained.

On the other hand, in the alloy wires of Comparative Examples 1 and 2 deviating from the alloy composition of the present invention, Comparative Example 1 having a high Mn content was used.
Shows that the conductivity and the corrosion resistance in an aqueous solution containing chloride ions are rapidly reduced. In Comparative Example 2 where the content of Mn is low, the conductivity shows good characteristics, but the corrosion resistance in an aqueous solution containing chloride ions sharply decreases as in Comparative Example 1.

Further, as shown in Table 2, the stranded wire of Example 9 using the highly corrosion-resistant conductor wire of the present invention contains highly corrosive chlorine ions, like the conductor wire of Table 1. Conventional example 4 which is currently used for electrical conductivity,
It has an excellent corrosion resistance of about one-tenth of that of the aluminum stranded wire and about 1/2 of an oxidizing acid such as nitrate ion.

[0043]

As described above in detail, in the high corrosion resistant transmission line according to the present invention, the conductor element wire constituting the stranded wire is heat-treated from an alloy containing a predetermined amount of Mn to form an Al-Mn intermetallic. High corrosion-resistant alloy wire composed of an alloy in which compounds are dispersed and deposited, or a high corrosion-resistant composite wire in which such an alloy is coated on various conductive aluminum or conductive aluminum alloy wires, so that water containing chlorine ions and the like is present. In a highly corrosive environment, it has extremely good corrosion resistance and a conductivity of 5
Since high conductivity of 0% IACS or more can be obtained, a high corrosion resistance transmission line having both corrosion resistance and conductivity can be obtained.

Further, as the conductor element wire constituting the stranded wire of the present invention, a conductor material having excellent conductivity, mechanical strength, heat resistance, etc. is used for the core material, and the above-mentioned alloy is used as the covering material, so that the corrosion resistance is improved. In addition to the above, it is possible to obtain a stranded wire excellent in properties such as conductivity, mechanical strength, heat resistance, etc., so it is applied to various purposes and environments such as transmission lines exposed to highly corrosive environments. It is possible to obtain a high corrosion resistant transmission line having a wide application range.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a transmission line according to the present invention.

FIG. 2 is a sectional view of another example of the transmission line of the present invention.

[Explanation of symbols]

 11 Al-Mn alloy wire 12 Galvanized steel wire 13 Al-Mn alloy covered aluminum wire

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koichi Saruwatari 1-5-1 Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd. (72) Inventor Shinji Katayama 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Co., Ltd. (72) Inventor Yutaka Nagata 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd. (72) Inventor Yuji 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Inside F-term (reference) 5G301 AA03 AA12 AA13 AB13 AD01 5G307 BA03 BB03 BC08 BC10 EA01 EC06 EF02

Claims (5)

[Claims] 1. A conductor strand constituting a stranded wire has Mn of 0.
It comprises a high corrosion-resistant aluminum alloy wire having a composition of 3 to 4.3% by weight, the balance being Al and unavoidable impurities, and an Al-Mn intermetallic compound dispersed and precipitated. High corrosion resistant transmission line. 2. The conductor strand constituting the stranded wire has Mn of 0.
3 to 4.3% by weight, 0.05 to 6.0% by weight of Mg, the balance being Al and unavoidable impurities, and the Al-Mn intermetallic compound is dispersed and deposited. A high corrosion-resistant transmission line, comprising a high corrosion-resistant aluminum alloy wire. 3. A conductor strand constituting a stranded wire contains 0.3 to 4.3% by weight of Mn in a core material of conductive aluminum or a conductive aluminum alloy, and the remainder is composed of Al and unavoidable impurities. A highly corrosion-resistant transmission line comprising a highly corrosion-resistant composite wire coated with an aluminum alloy having a composition represented by the formula below and having an Al-Mn intermetallic compound dispersed and precipitated. 4. A conductor strand forming a stranded wire is formed by adding 0.3 to 4.3% by weight of Mn and 0.05 to 6.0% by weight of Mg to a core material of conductive aluminum or conductive aluminum alloy. %
It is characterized by comprising a high corrosion resistant composite wire coated with an aluminum alloy having a composition consisting of Al and unavoidable impurities, with the balance being Al and Mn-based intermetallic compounds dispersedly deposited. High corrosion resistant transmission line. 5. A high-strength conductor wire comprising at least two conductor wires selected from the high-corrosion-resistant alloy wire and the high-corrosion-resistive composite wire according to claim 1. Corrosion resistant transmission lines.