JP3602223B2

JP3602223B2 - Power cable insulation connection insulation tube

Info

Publication number: JP3602223B2
Application number: JP27783595A
Authority: JP
Inventors: 明年渡辺; 清一奥山; 正之丹; 善之藤井; 勝哉山上; 勝直篠田
Original assignee: Fujikura Ltd
Current assignee: Fujikura Ltd
Priority date: 1995-10-25
Filing date: 1995-10-25
Publication date: 2004-12-15
Anticipated expiration: 2015-10-25
Also published as: JPH09121439A

Description

【０００１】
【発明の属する技術分野】
この発明は、長尺電力ケーブル等で適用される工場ジョイント（以下ＦＪという）にて絶縁接続部（以下ＩＪという）に使用される絶縁筒に関するものである。
【０００２】
【従来の技術】
長距離スパン地中線路や、現地にて接続部施工が不可能な線路（橋梁部分など）への対応として工場内で接続部を組立て長尺ケーブルとして出荷する方法が取られる。
【０００３】
ＡＣの電力ケーブルはしゃへい層及び金属シースに生ずる誘起電圧、送電ロスを低減するためにある一定距離間隔で撚架が行なわれる。これにはＩＪを設ける必要があり、ＩＪにはケーブル外部半導電層の縁切り、金属しゃへい層の縁切りを行うが、金属しゃへい層の縁切りにはエポキシ注型品等により構成される絶縁筒を使用している。
【０００４】
この絶縁筒は図２に示すように、エポキシ絶縁体２とその両側の金属の支持管３からなっている。
【０００５】
一般にＦＪにて金属しゃへい層間にこの絶縁筒を施工した後、そのまま布設現場へ運搬され、ケーブルと同じ様に延線される。従って、この絶縁筒はケーブルと同様の機械力の履歴を受けるのでケーブルと同等レベルの機械特性が要求される。
【０００６】
【発明が解決しようとする課題】
上記ＦＪにて絶縁等を施工した後、そのまま布設現場へ運搬し延線する場合、絶縁筒部が非可撓部となるため、運搬及び延線時に受ける歪み、曲げに対して次のような問題点があった。
【０００７】
（１）絶縁筒のエポキシ絶縁体及びエポキシ絶縁体端部と支持管部の破損。
【０００８】
（２）非可撓部の存在により、その周辺の可動部に適度の応力が集中し、ケーブル金属被にクラックが発生することがある。
【０００９】
（３）上記のことから、ＩＪ部分については許容曲げ径の見直し、引張り張力の緩和等の特別な措置が必要であり、延線条件の厳しい線路形態では延線不可能な場合もある。
【００１０】
【課題を解決するための手段】
本発明は前述のごとき問題に鑑みてなされたもので、電力ケーブルの工場ジョイントにおいて金属しゃへい層の絶縁接続に使用する絶縁筒であって、該絶縁筒は中央に備えた絶縁体管とその両側に備えた金属支持管を一体的に有し、上記両金属支持管は、前記電力ケーブルに被着した金属コルゲート管と接続してあり、前記絶縁体管を可撓性エポキシ材又は可撓性ＦＲＰにて可撓性に構成し、かつ前記金属支持管を、可撓性を有する波形管にて構成してあり、前記絶縁体の曲げ剛性よりも前記金属支持管の曲げ剛性を小さくし、かつこの金属支持管の曲げ剛性よりも前記金属コルゲート管の曲げ剛性を小さくしてなることを特徴とするものである。
【００１１】
【発明の実施の形態】
以下図面によりこの発明の実施の形態を説明する図１は、絶縁筒１を取付けた状態を示す部分断面図である。この絶縁筒１の取付は次のように行う。先づＦＪにてケーブル１０ａとケーブル１０ｂとの接続するに当たり、ケーブル導体１１ａとケーブル導体１１ｂを圧縮スリーブ（図示せず）等で接続し、その上に接続部補強絶縁層１２を施す。そうして、ケーブル外部半導電層の縁切り処理を行い接続部全体を例えばアルミニウムコルゲート管４を被着する。被着後その両端をケーブル金属シース１３ａ，１３ｂと溶接５によって接続する。上記のアルミニウムコルゲート管４には、どちらかの片側を切断して、その間に、絶縁筒１が溶接５によって接続されている。
【００１２】
図２に、絶縁筒１の部分断面図を示す。絶縁筒１はエポキシ絶縁体２とアルミニウム、ステンレス等の支持管３からなっている。
【００１３】
前記絶縁筒１は、エポキシ絶縁体２を可撓性エポキシ材又は可撓性ＦＲＰにて形成してある。可撓性エポキシ絶縁体２は、図３に示すようにエポキシ樹脂を含浸したガラステープ２ａを積層して所定の形状にしたうえで、接着剤、加熱により前記支持管３と一体に形成してある。
【００１４】
絶縁筒１の金属の前記支持管３は、図４に示すように、波形管にて構成してある。波形の形状としては、図５（イ）のように、らせん形のコルゲート形状と、図５（ロ）のように、山部と谷部がそれぞれ独立に円周を作る形状とがある。
【００１５】
前記構成において、絶縁筒１のエポキシ絶縁体２の曲げ剛性（ＥＩ）＞絶縁筒１の金属支持管３の曲げ剛性（ＥＩ）＞ケーブル接続部金属コルゲート管４の曲げ剛性（ＥＩ）の関係が成立するように金属支持管３の肉厚、波形状を選定してある。
【００１６】
【発明の効果】
以上のごとき説明より理解されるように、本発明においては、電力ケーブルの工場ジョイントにおいて金属しゃへい層の絶縁接続に使用する絶縁筒であって、該絶縁筒は中央に備えた絶縁体管とその両側に備えた金属支持管を一体的に有し、上記両金属支持管は、前記電力ケーブルに被着した金属コルゲート管と接続してあり、前記絶縁体管を可撓性エポキシ材又は可撓性ＦＲＰにて可撓性に構成し、かつ前記金属支持管を、可撓性を有する波形管にて構成してあり、前記絶縁体の曲げ剛性よりも前記金属支持管の曲げ剛性を小さくし、かつこの金属支持管の曲げ剛性よりも前記金属コルゲート管の曲げ剛性を小さくしてなるものであるから、接続部の周辺への応力集中が緩和され、工場出荷後の運搬、延線が容易となる。
【図面の簡単な説明】
【図１】この発明の絶縁筒を取付けた状態を示す部分断面図である。
【図２】絶縁筒の部分断面図である。
【図３】この発明の絶縁筒の可撓性絶縁体の説明図である。
【図４】この発明の他の実施形態の絶縁筒の部分断面図である。
【図５】図４の金属支持管の波形状の説明図であって、（イ）はらせん状のコールゲート管を、（ロ）は山と谷が各々独立した円周を形成した波形管を表す。
【符号の説明】
１絶縁筒
２絶縁筒エポキシ絶縁体管
３絶縁筒金属支持管
４ケーブル接続部金属被
５溶接部
１０ａ，１０ｂ電力ケーブル
１１ａ，１１ｂ電力ケーブル導体
１２接続部補強絶縁層
１３ａ，１３ｂ電力ケーブル金属シース[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an insulating cylinder used for an insulated connecting portion (hereinafter, referred to as IJ) in a factory joint (hereinafter, referred to as FJ) applied to a long power cable or the like.
[0002]
[Prior art]
In order to respond to long span underground tracks and tracks where connecting sections cannot be constructed locally (such as bridges), a method of assembling the connecting sections in the factory and shipping them as long cables is used.
[0003]
An AC power cable is twisted at a certain distance interval to reduce induced voltage and power transmission loss generated in a shielding layer and a metal sheath. It is necessary to provide an IJ, and the IJ cuts the outer semiconductive layer of the cable and the metal shielding layer. For the cutting of the metal shielding layer, use an insulating cylinder made of epoxy casting etc. are doing.
[0004]
As shown in FIG. 2, this insulating cylinder comprises an epoxy insulator 2 and metal support tubes 3 on both sides thereof.
[0005]
Generally, after installing this insulating tube between metal shielding layers at the FJ, it is transported to the laying site as it is, and is extended in the same manner as a cable. Therefore, the insulating cylinder receives the same mechanical force history as that of the cable, so that the same level of mechanical characteristics as the cable is required.
[0006]
[Problems to be solved by the invention]
When insulation and the like are constructed at the above FJ, and then transported to the laying site as it is and extended, the insulating cylinder part becomes an inflexible part. There was a problem.
[0007]
(1) The epoxy insulator of the insulating cylinder, the end of the epoxy insulator, and the support tube are damaged.
[0008]
(2) Due to the presence of the non-flexible portion, an appropriate stress is concentrated on the movable portion around the non-flexible portion, and cracks may occur in the cable metal jacket.
[0009]
(3) From the above, special measures such as review of the allowable bending diameter and relaxation of the tensile tension are required for the IJ portion, and in some cases, it is not possible to extend the wire in the form of a line having severe extension conditions.
[0010]
[Means for Solving the Problems]
The present invention has been made in view of the above problems, and is an insulating tube used for insulated connection of a metal shielding layer in a power cable factory joint, wherein the insulating tube includes an insulating tube provided at the center and both sides thereof. integrally has a metal support tube provided in said two metal support tube, Yes connected to the metal corrugated tube is applied to the power cable, wherein the insulator tube flexible epoxy material or flexible FRP is configured to be flexible , and the metal support tube is formed of a flexible corrugated tube , the bending rigidity of the metal support tube is smaller than the bending rigidity of the insulator, In addition, the bending rigidity of the metal corrugated pipe is made smaller than the bending rigidity of the metal supporting pipe .
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a partial cross-sectional view showing a state in which an insulating tube 1 is attached, illustrating an embodiment of the present invention with reference to the drawings. The mounting of the insulating cylinder 1 is performed as follows. Before connecting the cable 10a and the cable 10b by the FJ, the cable conductor 11a and the cable conductor 11b are connected by a compression sleeve (not shown) or the like, and the connection portion reinforcing insulating layer 12 is applied thereon. In this way, the outer semiconductive layer of the cable is trimmed, and the entire connecting portion is covered with, for example, an aluminum corrugated tube 4. After the attachment, both ends are connected to the cable metal sheaths 13a and 13b by welding 5. One of the two sides is cut to the aluminum corrugated pipe 4, and the insulating cylinder 1 is connected to the aluminum corrugated pipe 4 by welding 5.
[0012]
FIG. 2 shows a partial cross-sectional view of the insulating cylinder 1. The insulating tube 1 comprises an epoxy insulator 2 and a support tube 3 made of aluminum, stainless steel or the like.
[0013]
The insulating tube 1, are an epoxy insulator 2 is formed of a flexible epoxy material or a flexible FRP. The flexible epoxy insulator 2 is formed by laminating a glass tape 2a impregnated with an epoxy resin into a predetermined shape as shown in FIG. 3, and then integrally formed with the support tube 3 by an adhesive and heating. is there.
[0014]
The support tube 3 of the metal of the insulating tube 1, as shown in FIG. 4, are constituted by corrugated tube. As the waveform shape, there are a spiral corrugated shape as shown in FIG. 5A and a shape in which the peaks and valleys independently form a circumference as shown in FIG. 5B.
[0015]
In the above configuration, the relationship of bending rigidity (EI) of the epoxy insulator 2 of the insulating cylinder 1> bending rigidity (EI) of the metal support tube 3 of the insulating cylinder 1> bending rigidity (EI) of the metal corrugated tube 4 of the cable connection part is satisfied. The thickness and the wave shape of the metal support tube 3 are selected so as to be established.
[0016]
【The invention's effect】
As understood from the above description, in the present invention, an insulating tube used for insulated connection of a metal shielding layer in a power cable factory joint, the insulating tube being provided with an insulator tube provided at the center and its insulator Metal support tubes provided on both sides are integrally provided, and the metal support tubes are connected to a metal corrugated tube attached to the power cable, and the insulator tube is made of a flexible epoxy material or a flexible epoxy material. The metal support tube is made of flexible FRP, and the metal support tube is made of a flexible corrugated tube, and the bending rigidity of the metal support tube is made smaller than the bending rigidity of the insulator. In addition, since the bending rigidity of the metal corrugated tube is made smaller than the bending rigidity of the metal supporting tube, stress concentration around the connecting portion is reduced, and transport and extension after factory shipment are easy. It becomes.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view showing a state where an insulating tube of the present invention is attached.
FIG. 2 is a partial sectional view of an insulating cylinder.
FIG. 3 is an explanatory view of a flexible insulator of the insulating cylinder of the present invention.
FIG. 4 is a partial sectional view of an insulating cylinder according to another embodiment of the present invention.
5A and 5B are explanatory diagrams of a corrugated shape of the metal support tube of FIG. 4, wherein (A) is a spiral call gate tube, and (B) is a corrugated tube in which peaks and valleys form independent circles. Represents
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Insulation tube 2 Insulation tube Epoxy insulator tube 3 Insulation tube Metal support tube 4 Cable connection part metal cover 5 Welded part 10a, 10b Power cable 11a, 11b Power cable conductor 12 Connection part reinforcement insulation layer 13a, 13b Power cable metal sheath

Claims

An insulating tube to be used for the insulating connection of the metal shielding layer at the factory joint power cable, the insulation barrel integrally has a metal support tube with the on both sides with the central insulator tube, both The metal support tube is connected to a metal corrugated tube attached to the power cable, the insulator tube is made of a flexible epoxy material or a flexible FRP, and the metal support tube is made flexible. Is constituted by a flexible corrugated tube , the bending rigidity of the metal supporting tube is made smaller than the bending rigidity of the insulator, and the bending rigidity of the metal supporting tube is smaller than the bending rigidity of the metal supporting tube. An insulated cylinder for a power cable insulated connection portion, characterized in that bending rigidity is reduced .