JP2001135147A - Overhead wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent residual stress cracking and prolong the life of a wire by forming a self-supporting overhead wire with an wire body stranded using soft copper wires instead of hard copper wires, as core wire conductors, which is suspended by a body supporting wire portion to bear a tensile force on the wire body in overhead mounting. SOLUTION: Soft copper stranded wires are used for conductors 13 in a wire body 11 to keep a residual stress extremely low and restrict the generation of stress corrosion cracking. With the soft copper stranded wires used for the conductors 13 in the wire body 11, a tensile force required for overhead mounting comes short, but it is compensated by a body supporting wire portion 12. Since the need for the wire body 11 to bear a stringing tensile force is eliminated, the tensile stress is reduced without hardening the soft copper conductors 13, and the stress corrosion cracking is restricted even if rainwater enters the strings.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、電柱間に架線され
て応力腐食割れの防止に有効な架空電線に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overhead electric wire which is wired between utility poles and is effective for preventing stress corrosion cracking.

【０００２】[0002]

【従来の技術】一般に、電柱間に架線される架空電線１
は、たとえば図２に示すように、複数本の硬銅線による
導体２を撚り合わせた上から絶縁体３で被覆している。
しかし、このような架空絶縁電線１にあっては、製造時
の伸線工程や撚り線工程で導体２に残留応力が生じる。
残留応力の生じた導体２間に架線使用中に雨水などの水
成分が浸入すると、長期使用にわたって通電によって導
体２が温度上昇し、応力腐食割れを発生しやすいといっ
た問題がある。2. Description of the Related Art In general, an overhead electric wire 1 to be installed between telephone poles.
For example, as shown in FIG. 2, a conductor 2 made of a plurality of hard copper wires is twisted and covered with an insulator 3.
However, in such an overhead insulated wire 1, residual stress is generated in the conductor 2 in a wire drawing process or a stranded wire process during manufacturing.
If a water component such as rainwater enters between the conductors 2 where residual stress is generated during use of the overhead wire, there is a problem that the temperature of the conductor 2 increases due to energization over a long period of use, and stress corrosion cracking is likely to occur.

【０００３】そうした応力腐食割れ問題を解決するため
に、図３に示すように、硬銅線による導体２間に充填混
和物４を充填することで、導体２間に雨水などが浸入す
るのを防止できるようにした架空電線１も周知である。In order to solve such a stress corrosion cracking problem, as shown in FIG. 3, by filling a filling mixture 4 between conductors 2 made of hard copper wire, it is possible to prevent rainwater or the like from entering between the conductors 2. An overhead electric wire 1 that can be prevented is also known.

【０００４】[0004]

【発明が解決しようとする課題】しかしながら、この図
２に示す従来の充填混和物４を導体２間に充填した架空
絶縁電線１にあっても、長期的には、充填混和物４が劣
化すると導体２との密着性が低下し、雨水などの浸入を
防止しきれなくなってしまう。結果、この場合も応力腐
食割れを十分に抑えることができない。また、そうした
充填混和物４を充填した分だけ電線重量が増大するため
に、導体２に働く引張応力が大きくなるといった逆効果
もある。However, even in the case of the overhead insulated wire 1 shown in FIG. 2 in which the filled mixture 4 is filled between the conductors 2 as shown in FIG. Adhesion with the conductor 2 is reduced, and it becomes impossible to prevent infiltration of rainwater or the like. As a result, also in this case, stress corrosion cracking cannot be sufficiently suppressed. Further, since the weight of the electric wire is increased by the amount of the filling mixture 4, there is an adverse effect that the tensile stress acting on the conductor 2 increases.

【０００５】したがって、本発明の目的は、芯線導体と
してそれまでの硬銅線に代えて軟銅線を用いて撚り合わ
せたものを電線本体とし、これを支持線で吊った形にし
て架線使用中に電線本体に働く張力を負担することで、
応力腐食割れを有効に防止できるようにした自己支持型
の架空電線を提供することにある。Accordingly, an object of the present invention is to provide an electric wire body in which a core conductor is stranded by using a soft copper wire instead of a hard copper wire, and the wire body is hung by a support wire to form a core conductor. The tension acting on the wire body
An object of the present invention is to provide a self-supporting overhead electric wire capable of effectively preventing stress corrosion cracking.

【０００６】[0006]

【課題を解決するための手段】本発明にかかる請求項１
に記載の架空電線は、軟銅素線による複数本の導体を撚
り合わせた表面を絶縁体によって被覆してなっている電
線本体部と、複数本の鋼線を撚り合わせた表面を前記絶
縁体によって一体成形して被覆して前記電線本体部に並
設された本体支持線部と、前記絶縁体によって一体成形
して前記電線本体部と前記本体支持線部とを一体に連結
する部分のつなぎ部と、からなっていることを特徴とす
る。Means for Solving the Problems Claim 1 according to the present invention.
The overhead electric wire according to the above, an electric wire body portion in which a surface obtained by twisting a plurality of conductors made of annealed copper wire is covered with an insulator, and a surface obtained by twisting a plurality of steel wires by the insulator. A main body support wire portion integrally formed and covered and arranged in parallel with the electric wire main body portion, and a connecting portion of a portion integrally formed with the insulator and integrally connecting the electric wire main body portion and the main body support wire portion And that it consists of.

【０００７】以上の構成から、従来のように電線本体部
を形成する導体として「硬銅撚り線」を用いると、導体
の温度上昇と相まってその導体間に雨水などが浸入した
場合は応力腐食割れを発生しやすい環境にあった。それ
に対して、本発明のように導体に「軟銅撚り線」を用い
ると、従来の硬銅撚り線に比べて残留応力が極めて小さ
く、応力腐食割れの発生を抑えることができる。[0007] From the above configuration, when a "hard copper stranded wire" is used as the conductor forming the electric wire main body as in the prior art, stress corrosion cracking occurs when rainwater or the like enters between the conductors due to the rise in the temperature of the conductors. Environment. On the other hand, when the "soft copper stranded wire" is used for the conductor as in the present invention, the residual stress is extremely small as compared with the conventional hard copper stranded wire, and the occurrence of stress corrosion cracking can be suppressed.

【０００８】しかし、軟銅撚り線を導体に用いて電線本
体部とした場合、硬銅撚り線による電線本体部と比べて
架線時に求められる張力は小さい。そうした電線本体部
の張力不足を「鋼線」の撚り線からなる本体支持線部で
補う。すなわち、電線本体部として要求される架線張力
つまり引張強さを本体支持線部でもって負担し、極端に
は電線本体部に架線張力がほとんどかからないようにす
る。したがって、電線本体部は架線張力を負担しないで
済むから、軟銅導体が硬化せずに引張応力を軽減でき
る。結果、架線中に雨水などが浸入した場合でも応力腐
食割れの発生を抑え、断線といった不都合を抑制して電
線を延命化させるので、自己支持型の架空電線に有効で
ある。[0008] However, when the wire body is formed by using a soft copper stranded wire as a conductor, the tension required at the time of the overhead wire is smaller than that of the wire body portion formed by the hard copper stranded wire. The lack of tension in the electric wire main body portion is compensated for by a main body support wire portion made of a stranded wire of “steel wire”. That is, the overhead wire tension, that is, the tensile strength, required for the electric wire main body portion is borne by the main body support wire portion, and extremely, the overhead wire tension is hardly applied to the electric wire main body portion. Therefore, the wire main body does not need to bear the overhead wire tension, so that the soft copper conductor does not harden and the tensile stress can be reduced. As a result, even if rainwater or the like infiltrates into the overhead line, the occurrence of stress corrosion cracking is suppressed, and the inconvenience such as disconnection is suppressed to extend the life of the electric wire, which is effective for a self-supporting overhead electric wire.

【０００９】また、請求項２に記載の架空電線は、前記
本体支持線部を形成する前記鋼線が亜鉛メッキを施して
なっていることを特徴とする。The overhead electric wire according to claim 2 is characterized in that the steel wire forming the main body support wire portion is galvanized.

【００１０】以上の構成から、裸線による鋼線を撚り合
わせるよりも、亜鉛メッキを施した鋼線を撚り合わせて
本体支持線部を形成することにより、防食性がなお一層
高められる。[0010] With the above structure, the corrosion resistance is further improved by twisting galvanized steel wires to form the main body supporting wire portion, rather than twisting bare steel wires.

【００１１】[0011]

【発明の実施の形態】以下、本発明にかかる架空電線の
実施の形態について、図面に基づいて詳細に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an overhead electric wire according to the present invention will be described below in detail with reference to the drawings.

【００１２】図１は、本実施の形態による架空電線１０
を示す断面図であり、電線本体部１１と本体支持線部１
２が平行につながって、その本体支持線部１２によって
架線中に求められる電線本体部１１の所要の張力を補う
自己支持型となっている。FIG. 1 shows an overhead electric wire 10 according to the present embodiment.
FIG. 3 is a cross-sectional view showing the electric wire main body 11 and the main body support wire 1.
2 are connected in parallel, and are of a self-supporting type that compensates for the required tension of the electric wire main body 11 required in the overhead wire by the main body support wire 12.

【００１３】そこで、電線本体部１１は、芯線の導体１
３に軟銅線を用いてその複数本を撚り合わせ、撚り合わ
せた表面を絶縁体１４で被覆して形成されている。絶縁
体１４は、ここではたとえばポリエチレンまたは架橋ポ
リエチレンが使用されている。Therefore, the electric wire main body 11 is connected to the conductor 1 of the core wire.
3 is formed by twisting a plurality of wires using a soft copper wire and covering the twisted surface with an insulator 14. The insulator 14 is, for example, polyethylene or cross-linked polyethylene.

【００１４】また、かかる電線本体部１１に平行につな
がる本体支持線部１２は、亜鉛メッキを施した複数本の
鋼線１５を撚り合わせて表面を上記絶縁体１４でもって
一体に被覆して形成されている。Further, the main body supporting wire portion 12 connected in parallel to the electric wire main body portion 11 is formed by twisting a plurality of galvanized steel wires 15 and integrally covering the surface with the insulator 14. Have been.

【００１５】電線本体部１１と本体支持線部１２は、絶
縁体１４と同質樹脂で一体成形されたつなぎ部１６でも
って瓢箪形またはダルマ形状につながっている。The wire main body 11 and the main body support wire 12 are connected in a gourd or dalma shape by a connecting portion 16 integrally formed of the same resin as the insulator 14.

【００１６】本実施の形態の架空電線１０は以上のよう
に構成されている。電線本体部１１を形成する芯線の導
体１３に軟銅線を用いたことにより、伸線工程や撚り線
工程において発生する残留応力は極めて小さい。しか
し、軟銅線であるがゆえに電線本体部１１として架線中
に求められる張力不足は否めない。そうした電線本体部
１１の張力不足を本体支持線部１２で負担する。この本
体支持線部１２を形成する複数本の鋼線１５としては、
より好ましくは各鋼線１５の表面に亜鉛メッキを施して
防食性や防錆性を高め、電線本体部１１に架線中の張力
がほとんど働かないようにするだけの引張強度が備わっ
ている。The overhead electric wire 10 of the present embodiment is configured as described above. By using a soft copper wire for the core conductor 13 forming the electric wire main body 11, residual stress generated in the wire drawing process or the stranded wire process is extremely small. However, since it is a soft copper wire, it is undeniable that there is insufficient tension required in the wire as the wire main body 11. Such insufficient tension of the wire main body 11 is borne by the main body support wire portion 12. As the plurality of steel wires 15 forming the main body support wire portion 12,
More preferably, the surface of each steel wire 15 is subjected to galvanization to enhance corrosion resistance and rust prevention, and the electric wire main body 11 is provided with a tensile strength enough to make almost no tension in the overhead wire work.

【００１７】すなわち、本体支持線部１２によって架線
中の張力のほとんどを負担される電線本体部１１にあっ
ては、芯線の導体１３として従来のように硬銅線を用い
ずとも軟銅線で十分に機能を果たすことができる。導体
１３が軟銅線であるから、前述のように残留応力は小さ
く、架線中に硬化しない。そのため、架線中に雨水など
が導体１３の撚り線間に浸入した場合でも、導体１３の
温度上昇と相まって応力腐食割れの発生を抑止でき、電
線断線などといった事態を回避でき、耐久性を著しく高
めることが可能になる。That is, in the electric wire main body 11 in which most of the tension in the overhead wire is borne by the main body support wire 12, the soft copper wire is sufficient as the core conductor 13 without using a hard copper wire as in the conventional case. Function. Since the conductor 13 is a soft copper wire, the residual stress is small as described above and does not harden during the overhead wire. Therefore, even when rainwater or the like enters between the twisted wires of the conductor 13 in the overhead wire, it is possible to suppress the occurrence of stress corrosion cracking in combination with the temperature rise of the conductor 13, to avoid a situation such as a break in the electric wire, and to significantly increase the durability. It becomes possible.

【００１８】[0018]

【発明の効果】以上説明したように、本発明にかかる請
求項１に記載の架空電線は、電線本体部を形成する導体
に軟銅撚り線を用いたことで、従来の硬銅撚り線に比べ
て残留応力が極めて小さく、応力腐食割れの発生を抑え
ることができる。軟銅撚り線を導体に用いて電線本体部
とした場合、硬銅撚り線による電線本体部と比べて架線
時に求められる張力は小さいが、そうした電線本体部の
張力不足を鋼線の撚り線からなる本体支持線部で補うこ
とができ、つまり電線本体部として要求される架線張力
つまり引張強さを本体支持線部でもって負担し、極端に
は電線本体部１１に架線張力がほとんどかからないよう
にする。したがって、電線本体部は架線張力を負担しな
いで済むから、軟銅による導体は硬化せずに引張応力を
軽減できる。結果、架線中に雨水などが浸入した場合で
も応力腐食割れの発生を抑え、断線といった不都合を抑
制して電線を延命化させるので、自己支持型の架空電線
に有効である。As described above, the overhead electric wire according to the first aspect of the present invention uses a soft copper stranded wire as the conductor forming the electric wire main body, thereby making it possible to reduce the size of the conventional hard copper stranded wire. Thus, the residual stress is extremely small, and the occurrence of stress corrosion cracking can be suppressed. In the case of using a soft copper stranded wire as the conductor for the wire main body, the tension required at the time of the overhead wire is smaller than that of the wire body using the hard copper stranded wire, but such a lack of tension of the wire main body is due to the steel wire stranded wire It can be supplemented by the main body support wire, that is, the overhead wire tension required for the electric wire main body, that is, the tensile strength is borne by the main body support wire portion, and extremely, the overhead wire tension is hardly applied to the electric wire main body 11. . Therefore, since the electric wire main body does not have to bear the overhead wire tension, the tensile stress can be reduced without hardening the conductor made of soft copper. As a result, even when rainwater or the like infiltrates into the overhead line, the occurrence of stress corrosion cracking is suppressed, and the inconvenience such as disconnection is suppressed to extend the life of the electric wire, which is effective for a self-supporting overhead electric wire.

【００１９】また、請求項２に記載の架空電線は、本体
支持線部を形成する鋼線に亜鉛メッキを施せば、裸線に
よる鋼線を撚り合わせるよりも防錆性や引張強度がなお
一層高められる。In the overhead electric wire according to the present invention, when the steel wire forming the main body support wire portion is galvanized, the rustproofness and the tensile strength are further improved as compared with the case of twisting a steel wire made of a bare wire. Enhanced.

【図面の簡単な説明】[Brief description of the drawings]

【図１】本発明にかかる実施の形態として自己支持型の
架空電線を示す断面図である。FIG. 1 is a sectional view showing a self-supporting overhead electric wire as an embodiment according to the present invention.

【図２】従来例の架空電線を示す断面図である。FIG. 2 is a sectional view showing a conventional overhead electric wire.

【図３】別の従来例の架空電線を示す断面図である。FIG. 3 is a cross-sectional view illustrating another conventional overhead electric wire.

【符号の説明】[Explanation of symbols]

１０ 自己支持型架空電線 １１ 電線本体部 １２ 本体支持線部 １３ 導体 １４ 絶縁体 １５ 亜鉛メッキ鋼線 １６ つなぎ部 DESCRIPTION OF SYMBOLS 10 Self-supporting overhead electric wire 11 Electric wire main body 12 Main body support wire 13 Conductor 14 Insulator 15 Galvanized steel wire 16 Connection

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 軟銅素線による複数本の導体を撚り合わ
せた表面を絶縁体によって被覆してなっている電線本体
部と、 複数本の鋼線を撚り合わせた表面を前記絶縁体によって
一体成形して被覆して前記電線本体部に並設された本体
支持線部と、 前記絶縁体によって一体成形して前記電線本体部と前記
本体支持線部とを一体に連結する部分のつなぎ部と、か
らなっていることを特徴とする架空電線。1. An electric wire body in which a surface obtained by twisting a plurality of conductors made of annealed copper wire is covered with an insulator, and a surface obtained by twisting a plurality of steel wires is integrally formed by the insulator. A main body supporting line portion which is covered and arranged in parallel with the electric wire main body portion, and a connecting portion of a portion which is integrally formed with the insulator and integrally connects the electric wire main body portion and the main body supporting line portion, An overhead electric wire, comprising: 【請求項２】 前記本体支持線部を形成する前記鋼線が
亜鉛メッキを施してなっていることを特徴とする請求項
１に記載の架空電線。2. The overhead electric wire according to claim 1, wherein said steel wire forming said main body support wire portion is galvanized.