JPH08223765A - Joint of power cable with optical fiber - Google Patents

Abstract

PURPOSE: To protect a joint perfectly while facilitating the laying work without requiring any additional anchor or the like. CONSTITUTION: Cable conductors are interconnected in airtight cases 12, 12' and the joint, including the airtight cases 12, 12', is covered entirely with an outer protective case 5. In the joint of such submarine cable or other direct embedding power cable with optical fiber, a closure 17 and the joint of power cables 10, 10' are encased integrally in the outer protective case 5 and the closure 17 pulls in a plurality of optical fibers 6 to be connected from same direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a repair joint for a submarine power cable, in which an optical fiber-containing power cable having an optical cable inserted under an armored iron wire connects the interrupted cable in the event of an anchorage or other accident. A submarine cable or other directly embedded optical five containing cable conductors that are connected in an airtight case and the entire joint part including the airtight case is covered by an external protective case. Power cable joints.

[0002]

2. Description of the Related Art Conventionally, when an accident such as an anchor being caught (anchor) occurs in an undersea power cable laid on the seabed, repair of the undersea power cable is performed on a portion damaged by the accident of the undersea power cable. Is removed by an appropriate length (exclusion of the accident point), and a sound submarine cable is connected to the removed section. In this repair, two points between the both ends of the healthy submarine power cable to be connected and the original submarine power cable are the parts to be connected (joined). In the following, the connected parts will be repair joints. (Repair junction box or repair joint).

Among the submarine power cables, there is a power cable with an optical fiber in which an optical cable is inserted under an armored iron wire, and the repair joint for connecting the interrupted cable at the time of anchorage or other accident about the power cable with the optical fiber, There are no reports on existing technology. By the way, considering a newly installed submarine cable, an example of a beach joint (DC250kv OF cable) is applicable to a repair joint as shown in FIG. 5, for example.

In FIG. 5, reference numeral 1 is an existing power cable containing optical fiber, and when the sound cable 1'is cut in excluding the accident point, the sound cable 1'does not include the optical fiber. Use a cable. At the repair joint, the connection 2 of the power cable 1 is completed, the iron wire retaining device 3 and the tension bolt 4 are assembled, and then the optical cables (optical fiber cables) 6 (plural) are provided in advance in the external protective case 5. Further, the connection box (closure) 7 for only the optical fiber cable 6 is provided at a position different from the connection 2 of the power cable, and is connected from the through hole 5a.

Further, the closure 7 is shown in FIG.
As shown in (b), the optical fiber cable 6 is inserted from both sides in the longitudinal direction to protect the optical fiber 6a.
The end of the US tube is held by the clamp member 7a, and the optical fiber 6a from the end of the SUS tube is wound around the thread-wound book type tray 6b to absorb the excess length. The optical fiber 6a pulled out from the book type tray 6b is connected in the middle of the two optical fiber holders 6c. In addition, 7b is an anticorrosion cover, and 7c is an SU having an anticorrosion layer.
An outer tube made of S, a metal sleeve 7d, and a tape winding portion 7e.

[0006]

The method of separating the closure 7 of the optical cable from the repair joint of the power cable has the following problems. (1) The number of steps for laying down the optical cable separately from the power cable increases. (2) Mechanical damage is easily given to the optical cable during this installation work. (3) Since the mechanically weak optical cable is separated and buried, it is also easily damaged by external force, and therefore special protection is required. (4) It is necessary to add a retracting device for the optical cable in the outer case for the power cable.

The present invention has been made in order to solve the above-mentioned problems of the prior art. The power cable containing the optical fiber can be installed easily, can completely protect the joint, and does not require a retaining device. The challenge is to provide a joint.

[0008]

The present invention has the following constitution in order to solve the above problems. The invention of claim 1 is a submarine cable in which cable conductors are connected to each other in an airtight case, and the entire joint portion including the airtight case is covered with an external protective case, or an optical five with a direct buried structure. A joint for an electric power cable, wherein the joint portion for the optical fiber and the joint portion for the electric cable are housed in an integral outer protective case. The invention of claim 2 is the joint of an optical fiber-containing power cable according to claim 1, characterized in that the connecting part of the optical fiber is adapted to draw a plurality of optical fibers to be connected from the same direction.

[0009]

According to the present invention, since the connecting portion of the optical fiber can be integrated with the connecting portion of the power cable, the construction work can be simplified. Also, a strong external protective case (usually made of steel pipe)
Since the optical closure and the adjacent optical fiber can be accommodated therein, the connection portion of the optical fiber can be completely protected from external force.
According to the second aspect of the present invention, since the optical fiber connecting portion draws all the fibers from one side, the total length of the optical fiber connecting portion is shortened. Also, the seal part of the optical fiber connection part is only on one side (1
/ 2), and the reliability of airtightness can be improved.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a half cross-sectional view in which one side of the description of the structure of the joint in the external protective case 5 is omitted, and FIG. 2 is an explanatory diagram of the arrangement of the closure (optical fiber connection part) in the external protective case, which is II- in FIG. FIG. 3 is a sectional view taken along the line II, FIG. 3 is a partial perspective view for explaining the arrangement of the closure, and FIG. 4 is an internal explanatory sectional view of the closure. In these figures, the same parts as those in FIG. 5 are designated by the same reference numerals and the description thereof is omitted.

In this embodiment, as shown in FIGS.
A joint for an optical fiber-containing power cable, to which the present invention is applied to a repair joy for an optical fiber-containing submarine power cable. In other words, this repair joint is intended to protect the optical fiber and the closure from external force by housing the closure in the external protective case of the repair joint for the power cable, and to improve so that the power cable and the power cable can be integrated with the sinking work. is there.

In FIG. 1, reference numerals 10 and 10 'are submarine power cables containing optical fibers, and 12 and 12' are connection boxes (airtight cases) for the power cables. 3, 3'is an external iron wire retaining device, 4 is a tension bolt for connecting and integrating 3, 3 ', and 5 is an external protective case made of steel pipe. Further, 6 is an optical fiber (optical fiber cable), which enters, for example, a SUS tube provided with an anticorrosion layer on its outer peripheral surface. Further, 17 is a closure. Reference numeral 18 is a spacer for fixing the closure.

Submarine power cables 10 and 1 containing optical fibers
0'can be an OF cable, a CV cable or any type of power cable. In FIGS. 1 to 3, an example of a single-core cable is shown as the submarine power cable 10 including an optical fiber, but this is an example, and three single-core cables (three phases) are connected to collectively protect the outside. The present invention can be applied to the case of storing in a case.

Further, a plurality of closures 17 can be accommodated in a distributed manner around the power cable according to the number of fibers of the optical fiber cable 6. In the embodiment, as shown in FIG. 2, the closure 17 is connected to the power cable 10,
Four pieces are arranged symmetrically around 10 '. In this case, considering the workability of connecting the optical fiber cable 6 and the surplus length, as shown in FIG.
As shown in FIG. 5, the optical fiber cable 6 can be accommodated with some allowance. That is, the optical fiber cable 6
This is because, when bending, the bending radius of the optical fiber cable 6 is limited due to the relationship between the strength of the protective tube of the cable and the characteristics of the optical fiber, and it is necessary to allow some room. The plurality of closures 17 are fixed to the spacer 18 by two bands 13a, and the optical fiber bull 6 is fixed to the tension bolt 4 by an appropriate number of binds 13b. Further, in FIG. 3, reference numeral 14 is an armored iron wire folded-back portion of the power cables 10 and 10 ′ containing the optical fiber.

In the closure 17, as shown in FIG. 4, the optical fiber cable 6 is inserted from one side (the left side in the figure), the end of the SUS tube is held by the clamp member 17a, and the optical fiber is fed from the end. Book-shaped tray 6b in which the fiber 6a (the optical fiber at one end is routed through 6d) is wound into a thread.
It is designed to be wrapped around to absorb excess length. The optical fiber 6a drawn out from the book type tray is connected in the middle of the two optical fiber holders 6c. On the contrary,
Conventionally, as shown in FIG. 6, the linear shape in which the optical fibers are inserted from both sides is usually used, but in the embodiment, since the optical fiber cables are stored from one side, the optical fiber cables 6 are inserted into the repair joint. The storage workability is improved and the total length of the repair joint can be shortened. If the closure 17 is made of a heat conductive metal, it can contribute to the heat dissipation of the power cable. Although the present invention is applied to the submarine power cable in the above-mentioned embodiment, the present invention can be applied to other cables such as a direct buried underground cable having an optical fiber.

[0016]

As described above, according to the invention of claim 1, the optical fiber connecting portion and the joint portion can be integrated, so that the laying work is simplified. Further, since the optical closure and the adjacent optical fiber are housed in a strong external protective case (steel pipe), it can be completely protected from external force. According to the second aspect, since the optical fiber closure draws all the fibers from one side, the total length of the closure becomes short. Also,
The sealing part of the closure is only one side (1/2), and the reliability against airtightness can be improved. Furthermore, if the optical connection part is made of a heat conductive metal, it can contribute to the heat dissipation of the power cable.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the structure inside an outer protective case of a joint according to an embodiment of the present invention, and is a half cross-sectional view with one side omitted.

FIG. 2 is a layout explanatory view of a closure (optical fiber connection box) in an outer protective case, and is a cross-sectional view taken along line II-II in FIG.

FIG. 3 is a partial perspective view illustrating an arrangement of closures.

4 (a) and 4 (b) are cross-sectional views for explaining the interior of the closure.

FIG. 5 is a structural explanatory view of a conventional repair joint,
It is a half cross-sectional view with one side omitted.

6 (a) and 6 (b) are explanatory views of the configuration of a conventional closure.

[Explanation of symbols]

 5 External protection case 6 Optical fiber cable 10, 10 'Submarine power cable with optical fiber 12, 12' Junction box (airtight case) 17 Closure

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Kobayashi 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Ltd. (72) Inventor Takayuki Hirasawa 1-1-5, Kiba, Koto-ku, Tokyo Shareholders Inside Fujikura Ltd. (72) Inventor Shigeo Shibuo 1-5-1 Kiba, Koto-ku, Tokyo Fujikura Ltd. (72) Inventor Takashi Maruyama 1-1-5 Kiba, Koto-ku, Tokyo Fujikura Ltd. (72) Inventor Toshiaki Hara 3-3-22 Nakanoshima, Kita-ku, Osaka-shi, Osaka Kansai Electric Power Co., Inc. (72) Inventor Kazuo Yokota 3-322 Nakanoshima, Kita-ku, Osaka, Osaka Kansai Electric Power Co., Inc. (72) Inventor Kazuki Terashima, 6-15-1, Ginza, Chuo-ku, Tokyo Power source development Co., Ltd.

Claims (2)

[Claims] 1. A submarine cable in which cable conductors are connected to each other in an airtight case, and the entire joint portion including the airtight case is covered by an external protective case, or other optical cable with optical five installed directly embedded therein. A joint for an optical fiber-containing power cable, characterized in that the connection portion of the optical fiber and the connection portion of the power cable are housed in an integrated outer protective case. 2. The joint of an electric power cable containing an optical fiber according to claim 1, wherein the optical fiber connecting portion is adapted to draw a plurality of optical fibers to be connected from the same direction.