JP2002279833A - Optical fiber compound overhead earth-wire and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical fiber compound overhead earth-wire that is superior in corrosion resistance by steadily preventing contact of dissimilar metals. SOLUTION: An aluminum layer is provided by extrusion process on the outer circumference of an optical fiber-housed stainless steel tube that is constructed by stranding a stainless steel tube housing an aluminum-coated steel wire or an aluminum system element wire and an optical fiber. The extrusion process is carried out by extruding aluminum in tubular form on the outside of the optical fiber-housed stainless steel tube, and the tubular aluminum is cooled in a state having a gap between the tubular aluminum and the optical fiber-housed stainless steel tube, and then, aluminum is coated in close contact as a layer on the outer circumference of the optical fiber-housed stainless steel tube through a molding dies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the field of the technology of combining an overhead power transmission line and an optical fiber, and more particularly to the technology of an optical fiber combined overhead ground wire in which an optical fiber is combined with an overhead ground wire.

[0002]

2. Description of the Related Art In response to the need for liberalization of communication and diversification of power maintenance information, an optical fiber is combined with an overhead ground wire of an overhead transmission line to integrate the functions of the transmission line and the communication line. Fiber composite overhead ground wires are widely used.

FIG. 6 shows an example of a conventional optical fiber composite overhead ground wire. An aluminum covered steel wire 3 having mechanical strength and electrical characteristics and an aluminum-based element wire 4 of aluminum or an aluminum alloy are shown. A stainless steel pipe 2 containing a large number of optical fibers 1 is used as a part of an overhead ground wire, and these are twisted together.

In such an optical fiber composite overhead ground wire,
A sacrificial anode action occurs between the stainless steel pipe 2 and the aluminum-coated steel wire 3 or the aluminum-based wire 4 due to the contact of the dissimilar metal, thereby corroding the aluminum surface and significantly impairing the mechanical and electrical properties of the electric wire. Due to the problem, the stainless steel pipe 2 and the constituent wires 3 and 4 of the overhead ground wire
The anticorrosive agent 14 was applied to the gaps.

[0005]

In the conventional optical fiber composite ground wire shown in FIG. 6, although the corrosion problem is solved by applying the anticorrosive agent 14, the anticorrosive agent is not used in the atmosphere. In 10 years, the anticorrosive effect is lost, and from that point on, corrosion due to dissimilar metal contact between aluminum and stainless steel progresses.

The stainless steel tube 2 containing the optical fiber is usually arranged in the second layer counting from the center as shown in FIG. 6 in order to reduce the elongation applied to the optical fiber 1. Considering that the anticorrosive agent applied to the outermost layer has particularly severe drying deterioration, a third structural element layer is provided, and the anticorrosive agent is applied between them to suppress the deterioration of the anticorrosive agent around the stainless steel pipe. . However, when the structure has a three-layer structure, the diameter of the electric wire is inevitably increased, and the load applied to the steel tower is increased.

On the other hand, in a stainless steel tube for storing an optical fiber, an aluminum plate is pressed against a stainless steel plate material before the tube is formed, and the plate material is formed into a tubular shape with the aluminum plate portion as an outer layer surface. A method of welding a joining surface in a longitudinal direction has been proposed (JP-A-7-30251).
No. 8). According to this proposal example, the outer layer surface is an aluminum surface, which seems to solve the above-mentioned problem, but has the following problem. That is, it is difficult to simultaneously weld the stainless steel plate and the aluminum plate, and the stainless steel plate is inevitably exposed at the joint surface. Therefore, sacrificial anodic action and corrosion due to the dissimilar metal contact between stainless steel and aluminum are inevitable.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and a problem thereof is to provide an optical fiber composite overhead ground wire excellent in corrosion resistance by reliably preventing contact with dissimilar metals. It is in.

[0009]

Means provided by the present invention: The optical fiber composite overhead ground wire is an optical fiber composite structure in which an aluminum-coated steel wire or an aluminum-based wire is twisted with a stainless steel tube containing an optical fiber. An aluminum layer is provided by extrusion on the outer periphery of a fiber-containing stainless steel tube. Thus, by providing the aluminum layer by extrusion on the outer periphery of the stainless steel pipe, the stainless steel pipe does not come into contact with the outer aluminum-coated steel wire or aluminum-based element wire, and the corrosion problem due to dissimilar metal contact can be solved. it can.

[0010] Further, the means for manufacturing the above-mentioned optical fiber composite overhead ground wire; the manufacturing method is to extrude aluminum into a tube outside the stainless steel tube containing the optical fiber and to interpose the aluminum between the tubular aluminum and the stainless steel tube containing the optical fiber. After cooling the tubular aluminum in a state having a gap, the outer periphery of the optical fiber-containing stainless steel pipe is tightly covered with aluminum as a layer through a forming die, and the optical fiber-containing steel pipe coated with this aluminum layer is covered with aluminum. A method of manufacturing an optical fiber composite overhead ground wire by twisting with a wire or an aluminum-based wire. As described above, aluminum formed as a layer on the outer periphery of the stainless steel pipe is extruded into a tubular shape with a gap outside the stainless steel tube, and by cooling the tubular aluminum, a stainless steel tube made of extruded aluminum, that is, The optical fiber composite overhead ground wire having the above configuration can be obtained by preventing the optical fiber housed therein from being affected by heat and then forming an aluminum layer on the outer periphery of the stainless steel pipe.

[0011]

Embodiments of the present invention will be described below. FIG. 1 shows a preferred embodiment of an optical fiber composite overhead ground wire according to the present invention. In this embodiment, an aluminum ground wire composed of a seven-stranded aluminum covered steel wire 3 (circular in cross section) and a stranded layer of an outermost aluminum element wire 4 (circular in cross section) is used. One of the covered steel wires 3 is replaced with a storage portion for the optical fiber 1, and an aluminum layer 5 is provided by extrusion on the outer periphery of a stainless steel tube 2 having a circular cross section in which a large number of the optical fibers 1 are stored. The aluminum layer 5 covers the entire outer periphery of the stainless steel pipe 2.
As described above, since the outer periphery of the stainless steel tube 2 is covered with the continuous aluminum layer 5, dissimilar metal contact between the stainless steel tube 2 and the aluminum portion of the aluminum-coated steel wire 3 and the aluminum-based element wire 4 adjacent thereto. As a result, there is no need to apply an anticorrosive as in the prior art. Thereby, (1) the stranded wire work becomes easy,
(2) It is possible to obtain an effect that it is possible to prevent the property under the line from being stained due to the fall of the anticorrosive agent during the overhead wire construction.

FIG. 2 shows an example of a method for manufacturing an optical fiber-containing stainless steel pipe having an aluminum layer of the above-mentioned optical fiber composite overhead ground wire. In this method, a rotating wheel type aluminum extruder is used, and the rotation of a rotating wheel 9 causes an aluminum material 11 supplied to a passage provided on the outer periphery of the nipple portion 7 to be supplied.
This is a mechanism in which the material is supplied to a material storage space 12 formed by the dies 8 and extruded from the dies 8.

In this aluminum extrusion apparatus, the stainless steel tube 2 containing the optical fiber 1 is supplied in the extrusion direction through the nipple portion 7 and the die portion 8, while the aluminum material 11 is extruded from the die portion 8 into a tubular shape. In a state where there is a gap between the stainless steel pipe 5a and the stainless steel pipe 2 containing the optical fiber supplied as described above, the tubular aluminum 5a is cooled by the cooling water 6 so that the stainless steel pipe and the optical fiber 1 are not thermally affected. Then, the tubular aluminum 5a is squeezed by the forming die 13 and tightly coated as an aluminum layer 5 on the outer periphery of the optical fiber-accommodating stainless steel tube 2 so that the optical fiber-accommodating stainless steel tube having the seamless aluminum layer 5 is provided. Is obtained.

FIG. 3 shows another embodiment 1 of the optical fiber composite overhead ground wire according to the present invention. In this embodiment, a seven-stranded aluminum-coated steel wire 3 (circular in cross section) is replaced by a single stainless steel pipe 2 (circular in cross section) having an aluminum layer 5 and replaced with one optical fiber. It is. According to this embodiment, the same effect as that of the above-described embodiment (FIG. 1) can be obtained. In addition, since it has a two-layer twist structure, it is not necessary to necessarily have a three-layer structure or more unlike the conventional case. The outer shape of the optical fiber composite overhead ground wire can be reduced.

FIG. 4 shows another embodiment 2 of the optical fiber composite overhead ground wire according to the present invention. In this embodiment, one wire outside the seven-stranded aluminum covered steel wire 3 (circular cross section) is replaced with an optical fiber 1-containing stainless steel tube 2 (circular cross section) having an aluminum layer 5 and twisted. Things. Even if the optical fiber storage stainless steel pipe 2 is provided as the outermost layer as in this embodiment, there is no possibility of electrolytic corrosion because the aluminum layer 5 is provided.

FIG. 5 shows another embodiment 3 of the optical fiber composite overhead ground wire according to the present invention. The configuration of the stranded wire of this embodiment is substantially the same as the seven-stranded configuration of FIG. 4, except that the outermost element wire is formed in a sector shape. That is,
An optical fiber 1-containing stainless steel tube 2 'having a sector-shaped aluminum-coated steel wire 3' and an aluminum layer 5 'having a sector-shaped cross-section is twisted on the outside of the aluminum-coated steel wire 3 having a circular cross-section at the center. . By doing so, the outer shape can be further reduced, and the load applied to the steel tower can be reduced. It should be noted that such a fan-shaped wire, in particular, an optical fiber-containing stainless steel pipe having an aluminum layer can be obtained by changing the shape of the extruder die and the shape of the forming die into a shape suitable for the fan-shaped extrusion in the extruder shown in FIG. It can be manufactured at

In the embodiments of FIGS. 4 and 5, the second-layer stranded wire may be an aluminum-based wire instead of the aluminum-coated steel wire.

[0018]

As described above, according to the present invention, it is possible to attain the intended object and the object of providing an optical fiber composite overhead ground wire excellent in corrosion resistance by reliably preventing contact with dissimilar metals. The effect is large.

[Brief description of the drawings]

FIG. 1 is a cross-sectional explanatory view showing an embodiment of an optical fiber composite overhead ground wire according to the present invention.

FIG. 2 is a cross-sectional explanatory view showing a method of manufacturing an optical fiber composite overhead ground wire according to the present invention by extruding aluminum into a stainless steel pipe containing an optical fiber.

FIG. 3 is an explanatory cross-sectional view showing another embodiment 1 of the optical fiber composite overhead ground wire according to the present invention.

FIG. 4 is a cross-sectional explanatory view showing another embodiment 2 of the optical fiber composite overhead ground wire according to the present invention.

5A and 5B show another embodiment 3 of the optical fiber composite overhead ground wire according to the present invention, wherein FIG. 5A is a cross-sectional explanatory view of an aluminum covered steel pipe containing an optical fiber, and FIG. FIG.

FIG. 6 is an explanatory cross-sectional view showing an example of a conventional optical fiber composite overhead ground wire.

[Explanation of symbols]

 Reference Signs List 1 optical fiber 2 stainless steel pipe (circular cross section) 2 'stainless steel pipe (cross section fan) 3 aluminum coated steel wire (cross section circular) 3' aluminum coated steel wire (cross section fan) 4 aluminum based wire (cross section circular) 4 'aluminum-based element wire (sector-shaped cross section) 5 aluminum layer 5' aluminum layer 5a tubular aluminum 6 cooling water 7 extruder nipple section 8 extruder die section 9 extruder wheel 10 wheel rotation direction 11 aluminum extruded material 12 aluminum Material storage space 13 Forming die

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // H01B 7/28 H01B 7/28 F (72) Inventor Hideo Tanaka 4-chome Kawajiri-cho, Hitachi City, Ibaraki Prefecture No. 1 F-term in Toyoura Plant of Hitachi Cable, Ltd. (reference) 2H001 DD05 DD07 DD23 FF02 KK06 KK19 KK24 MM01 MM06 5G313 FA04 FB10 FC10 FD14 5G319 HA01 HA10 HB03 HC01 HD01 HE14 HE26

Claims (2)

[Claims] 1. An optical fiber storage stainless steel pipe having a structure in which an aluminum covered steel wire or an aluminum-based wire and a stainless steel pipe containing an optical fiber are twisted, and an aluminum layer is provided on an outer periphery of the optical fiber storage stainless steel pipe. Optical fiber composite overhead ground wire. 2. Aluminum is extruded into a tube outside the stainless steel tube containing the optical fiber, and the aluminum tube is cooled with a gap between the aluminum tube and the stainless steel tube containing the optical fiber. Aluminum is tightly coated as a layer on the outer circumference of the stainless steel tube containing the optical fiber through a die, and the steel tube coated with the aluminum layer is twisted with an aluminum-coated steel wire or aluminum-based wire to produce an optical fiber composite overhead ground wire A method for producing an optical fiber composite overhead ground wire.