JP3210536B2 - Submarine cable laying ship and landing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to laying of a submarine cable or the like which connects between continents or the like via the ocean, and in particular, laying a submarine cable particularly useful for pulling a submarine optical cable to a land station. It concerns ships and landing methods.

[0002]

2. Description of the Related Art When a submarine cable laid via an ocean or a port is discharged to a landing station, a work boat A equipped with necessary equipment as shown in FIG. A ship capable of performing such operations is simply referred to as a submarine cable laying ship) operated from a predetermined position B offshore from the landing station to the coast C of the landing station, and floated on a cable D for landing. The ship is towing toward the shore with the mark attached, and the submarine cable is landing.

[0003] By the way, terminal stations for submarine cable landings constructed on the beach or the like are equipped with terminal equipment so that a plurality of submarine cable main lines usually sent across the ocean are landed. When landing a plurality of these submarine cable main lines, it is customary to individually perform landing operations for each submarine cable by operating the above-described laying ship.

[0004] In other words, the cable is landed every single line from the viewpoint of the handling properties of the submarine cable, the subsequent laying work is performed, and then the submarine cable is protected from fishing and human obstacles. The work of burying between 0.5 m and 1.5 m is performed.

[0005]

However, when a plurality of submarine cables are unloaded one by one as described above, there are many problems as described below. (1) If a plurality of cables are used for unloading work on a line-by-line basis, the construction period will be relatively long and the construction cost will increase accordingly. That is, the landing work usually starts with the preparation work of the station building site and the beach area, and consists of the landing work and the restoration work. The preparation work includes the work of opening a cable pipe for leading from the beach to the station building and the opening of a cable routing route on the premises, and usually has a deadline of two weeks depending on the landing station. (2) In addition, landing work is carried out with the ship compacted offshore, but it is easily affected by the weather, so the cable terminal is led from the ship to the shore due to bad weather, or from the regular laying route. Or come off. Even after the preparation work is completed, the implementation of the landing work may be delayed due to the weather. (3) For restoration work, bury the cable in the portion that was cut out during the preparatory work, provide necessary protection, and backfill. In addition, in order to protect the laid cables from obstacles such as fishing, it is necessary to bury the cables below the seabed, and these are performed continuously. It takes about 3 months, though.

[0006] In the above-mentioned conventional construction method, such various constructions and operations are carried out every time one cable is landed. If three cables are landed, a total of 9 cables are required.
It takes a period of months, and the total construction cost increases as the construction takes a long time. In this way, it is necessary to secure the laying area in the sea area before the landing station for a long period of time, but there are times when existing cables are buried in this sea area, so that this cable is not damaged. Construction is restricted. In addition, there may be a problem with the position of the compaction of the work boat at the time of landing.

In order to solve these problems, it has been considered that a plurality of landing cables are bundled at the stage of manufacturing a submarine cable to form a single cable for landing work. However, if the landing operation of the submarine cable is performed once in the landing station where a plurality of cables are bundled in the manufacturing stage, the following problem occurs.

Usually, a single outer cable can be wound with a minimum radius of curvature of about 1.5 m and has good handleability. However, when three such cables are bundled together, the radius of curvature is 5 m or more. It is necessary to wind in. Then, when such a cable is mounted on a laying ship, a cable tank having a very large radius is required, and a corresponding laying ship is required, and the economic burden is increased.

[0009] In addition, the weight of such a cable makes it difficult to ship it from a factory and load the cable due to an increase in weight, and there is a possibility that the cable may be damaged. In addition, even if one cable fails during the landing work, the entire cable is bundled in advance, so repairs to break the cable cannot be performed, and the result is that the landing work must be performed again. The problem is that the landing work is prolonged.

[0010]

SUMMARY OF THE INVENTION The present invention solves these problems all at once, and achieves a low-cost and highly reliable landing method in comparison with the conventional method. Two or more cable tanks for storing submarine cables,
A first cable guide for collecting submarine cables drawn from the cable tank at a predetermined position, a lashing device for winding a restraining wire around the submarine cables collected by the first cable guide, and the lashing A cable engine that pulls out the submarine cable integrated by the device at a predetermined speed,
The submarine cable drawn from the cable engine is guided and can be dropped into the sea from the bow or the stern.

Further, the lashing device includes a gutter through which at least two or more submarine cables pass, a cylindrical rotary head rotating around the gutter with the cable traveling direction as an axis, and a submarine cable. A wire for binding is wound around the bobbin, which rotates together with the rotary head, and an electric motor for rotating the head at a predetermined number of rotations. In addition, the rotating head portion is configured to be able to be divided into two, especially in case a cable breaking operation is required when bundling the cables.
In addition, the present invention bundles a submarine cable integrated with a wire by such a submarine cable laying ship for landing from the sea near the landing station to a predetermined distance offshore, or conversely, from offshore to near the landing station. The present invention provides a landing method in which two or more submarine cables are collectively landed by laying a cable and connecting the submarine cable main line and the integrated exterior cable for landing.

[0012]

The lashing device provided on the laying ship bundles a plurality of landing cables drawn out of the cable tank, restrains them with wires, etc., and drops them onto the sea. The lifting cable can be routed to the beach in one operation, and various subsequent operations, such as burying, lifting, and restoring the cable, can be integrated and performed at the same time. for that reason,
The construction period is shortened and the occupation period of the work area near the landing station is shortened, so that significant economic benefits are generated.

[0013]

1 shows a side view of a main part of a submarine cable laying ship for realizing a submarine cable, in particular, a submarine optical cable landing method according to the present invention, and FIG. 2 shows a top view of FIG. The outline of various outfitting equipments is shown. The three circles described at the center in this figure are cable tanks 1 (A, B, C) in which submarine cables for landing are housed in a coil shape, and 2 (A, B). , C) are cable troughs for guiding and guiding the submarine cables pulled up from the cable tanks 1 (A, B, C). In the case of this embodiment, the number of submarine cables for landing is three, and in particular, the scale is such that the three submarine cables can pass through the cable trough 2C while descending.

The cable trough 2C for moving the cable
A lashing device 3 (also referred to as a cable collecting device) for collecting cables, which will be described later, is disposed on the outlet side of the cable. The lashing device 3 pulls out each cable tank 2 (A, B, C). For example, three submarine cables are constrained by wires or the like so as to be integrated as a single cable. 4 is a lashing device 3
A cable engine for moving the cable integrated at a predetermined speed at a predetermined speed. The cable engine 4 pulls the cable in accordance with the operating speed of the laying ship and supplies the cable to a dynamo device 5 for the next tension measurement. I do. Then, the tension at the time of dropping the cable is controlled by the dynamo device 5 so as to be a predetermined value, and the cable is dropped onto the ocean via the stun chute 6 provided at the stern (bow). .

The cables assembled for landing only pass through the lashing device 3 while being pulled by the cable engine 4, so that it is not necessary to maintain the tension of the cables in the lashing device 3. ing. Further, the cable engine 4 is a sub-cable engine 4 used when it is necessary to branch a part of a submarine cable constrained by wires so that it can be extended later and drop it separately.
A, for example, is configured so that a landing cable can be branched at an arbitrary location and dropped from the second stun chute 6A as a two-layer landing cable.

Next, the outline of the lashing device 3 will be described with reference to FIGS. FIG. 3 shows a case where the lashing device is viewed from its side, where 10 is a base, 1
Reference numerals 1 and 12 denote first and second cable guides, which are arranged upright at both ends of the base, above and below the cable guides # 11 and 12, respectively. A pair of rollers for regulating and guiding is provided.

Reference numeral 13 denotes a support for holding an assembly machine for winding the restraining wire 21 around the three cables 20 assembled by the second cable guide 12. The support 13 has An electric motor 14, a cylindrical head 15 rotationally driven by the electric motor 14, and a gutter 13A (FIG. 4) through which three cables pass are supported. The head 15 has a plurality of small rollers 16, 16, 16.
························· Contact with cylindrical rails provided on both measurement sides of the gutter section 13A by means of. Is held.

FIG. 4 shows a cross section of the head 15. The cylindrical head 15 has a small gear 14A which meshes with a ring gear provided on one side end surface, and a small gear 14A.
The motor 14 is rotationally driven by a large gear 14B coupled to the rotating shaft of the electric motor 14. The gutter portion 13A fixed to the support base 13 is arranged so that three cables 20 can pass therethrough. Also, two bobbins 1 are provided on the outer peripheral side surface of the cylindrical head 15.
7 and 17 are rotatably mounted, and the wire 21 wound on the two bobbins 17 and 17 is unreeled from the rotating guide rollers 18 and 19 together with the head 15 which is appropriately tensioned. I am trying to be.

As shown in FIG. 4, the cylindrical head 15 of the lashing device 3 mounted on the laying ship of the present invention has a substantially one-third circular arc portion 15A, as shown by an arrow X, a Y-axis. The Z point is opened upward using the point as a hinge, and can be opened as shown by a dotted line. And
In this open state, any one of the submarine cables 20A passing through the gutter portion 13A can be pulled out from the outer periphery of the head 15 as shown by an arrow V as shown in FIG. Designed. FIG. 5 is a perspective view showing this open state, and the same parts as those in FIG. 4 are denoted by the same reference numerals.

Therefore, as shown in FIG.
The three cables 20 guided from the cable guide 12 side of the head 15 and passing rightward through the gutter 13A in the head 15 are rotated around the bobbin 17 by the rotation of the head 15 during the passage. Is wound, and the cable bound and integrated by the wire 21 is pulled and pulled out from the first cable guide 11 by the above-described cable engine 4 as a single cable.

The cable is dropped from the stun chute 6 onto the sea as a single cable, and laid from the offshore to the beach as a submarine cable for landing. In addition, by attaching a float at the time of dropping, the cable can be pulled to a predetermined position and settled later.
If necessary during this laying work, once the cable drop is stopped, a part of the head of the lashing device (15A)
, For example, one cable 20A is moved from the gutter 13A to the outside. Then, after that, a part of the head (15A) is closed again and fixed with a fixing bracket (not shown), and the wire 21 is wound around the remaining two cables by operating the lashing device.
Can work like dropping into the ocean. By dropping the ocean while simultaneously pulling the branched cable by the double-cable engine 4A, landing of the submarine cable is achieved by one operation of the laying boat.

Although the present invention has been described in connection with the case where three landing cables are laid all at once, the present invention can be applied to a case where two or four cables are laid. However, in general, when three cables are laid and laid, the handling as a single cable is the most stable. For example, in the case of two cables, a set of three cables can be used using a dummy cable. Preferably, it is a cable. The wire 21 has a radius of 3.2 mm.
About 900 m can be accommodated in the bobbin, but a wire for restraining can be used instead of the wire 21. And the winding pitch is 1 to 2
m is preferable.

[0023]

As described above, the submarine cable laying ship of the present invention collects and integrates two or more cables with the laying of the landing cable for landing the coastal submarine cable on land. Lashing equipment is installed and the cable drawn from the cable tank is laid by one operation, so that the various construction periods required for conventional landing operations are greatly reduced and the construction cost is reduced by half. Alternatively, an excellent effect of being able to be reduced to a fraction can be exhibited.

Also, since cables can be buried on the seabed while being bundled, construction work and restoration work can be performed on a plurality of cables at the same time. The period during which a certain fishery is hindered is shortened. In addition, the cable laying route in the sea area in front of the landing station has a margin, and the distance between the existing cable and the existing cable can be increased.

The landing method using the laying ship of the present invention not only has the effect of shortening the construction period and reducing the construction cost as described above, but also has the effect of increasing the number of landings of submarine cables that will be expanded in the future. There are significant economic benefits as they can capture forecasts and achieve their plans without a significant increase in costs.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a submarine cable laying ship of the present invention.

FIG. 2 is a top view of a submarine cable laying ship of the present invention.

FIG. 3 is a side view showing an outline of a lashing device mounted on the laying ship.

FIG. 4 is a sectional view of a part of the lashing device of FIG. 3;

FIG. 5 is a perspective view when a part of the submarine cable restrained by the lashing device is taken out.

FIG. 6 is an explanatory diagram showing an outline of landing of a submarine cable.

[Explanation of symbols]

 Reference Signs List 1 (A, B, C) Cable tank 2 (A, B, C) Cable trough 3 Lashing device 4 (4A) Cable engine 6 (6A) Stun chute 11, 12 Eleventh and second cable guides 14 Motor 15 head 20 Submarine cable for landing 21 Wire

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masakazu Nasu 2-3-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo International Telegraph and Telephone Corporation (72) Inventor Ikuo Marume 2-3-Nishishinjuku, Shinjuku-ku, Tokyo No. 2 International Telegraph and Telephone Corporation (72) Inventor Yukihiro Fujii 2-3-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo International Telegraph and Telephone Corporation (56) References JP-A-53-80693 (JP, A) JP-A-62-25807 (JP, A) JP-A-53-29593 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02G 9/02 B63B 35/04

Claims (2)

(57) [Claims] At least two submarine cables , at least two submarine cables, a plurality of submarine cables, and a first cable guide for collecting a plurality of submarine cables drawn from the submarine cables at predetermined positions. Gutter part through which
It rotates around the gutter part about the traveling direction of the cable as an axis,
To remove at least one cable passing through the gutter
And a cylinder whose part can be opened and closed so that it can be divided into two
Rotating head and a wire for restraining the submarine cable.
The ear is wound and rotates with the rotary head.
The bobbin and the head section at a predetermined number of rotations.
Motor, and assembled by the first cable guide.
Remove at least one of the submarine cables
Split into single submarine cable and multiple submarine cables
At the same time, a restraining wire is attached to the plurality of cables.
Lassin forms an integrated submarine cable by winding
And grayed device is the integrated formed by the lashing device
Main cable that pulls out the submarine cable at a specified speed
Connect the engine and the single submarine cable at a specified speed
Secondary cable engine to be pulled out and cable drawn out by the main cable engine
Measure the tension of the cable and make sure that the
A dynamometer which is controlled to be, the integral being drawn from the main cable engine
Submerged cable from the bow or stern
First stun chute and drop-in cable for dropping
Single submarine cable drawn from the engine
Second to guide the ship and drop it into the sea from the bow or stern
An integrated submarine cable with a stun chute and / or the single sea
Route the bottom cable between the offshore at a predetermined distance from the sea near the landing station.
Lay the submarine cable main line and the integrated submarine cable
Cable and / or the above single-line submarine cable
To unload two or more submarine cables at once.
Cable layer for landing characterized by and. 2. The submarine cable laying ship according to claim 1, wherein the number of rotations of the electric motor is variable in accordance with a drawing speed of the submarine cable.