JP2006158160A - Long-sized body for marine floating body and its laying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for laying a long-sized body for a marine floating body, by which a long-sized body damaged in the sea can be rapidly replaced. <P>SOLUTION: A submarine cable 4A connected to a platform 10 side and a submarine cable 4B connected to offshore equipment 20 side are connected with a connection part 28 equipped to an underwater buoy 6. When the submarine cable 4B is damaged, the connection part 28 is removed from the underwater buoy 6 and moved to offshore or near to the surface of the sea, where the damaged submarine cable 4B is replaced. After the completion of replacement, the connection part 28 is reinstalled to the underwater buoy 6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a seafloor long body capable of connecting and laying between a floating body and a long body such as a submarine cable, and a laying method thereof, and in particular, a long body damaged in the sea. It is related with the elongate body for sea floating bodies which can replace | exchange rapidly, and its laying method.

  For example, in order to supply power, water, etc. to offshore facilities floating on the sea offshore, power plants, crude oil reservoirs, docks, etc., and to communicate, the submarine cables (power cables) , Communication cables, optical composite power cables), water supply pipes, oil feed pipes and the like are laid on the seabed.

  Such a long body floats with a buoy from the sea floor to the sea on the way to the offshore facility, and has catenaries on both sides of the buoy. This employs a laying method that prevents abnormal tension from being applied to the long body even if the offshore facilities are moved up, down, left, and right under the influence of waves, winds, and tidal currents.

  FIG. 2 shows the structure of a marine facility using a conventional long body for floating bodies. The offshore facility 30 is erected on the sea floor 2 near the land, and the top 10 is exposed from the sea surface 3. The offshore floating body 20 is installed between the platform 10 and the offshore floating body 20. The two submarine cables 14A and 14B to be installed, the connecting portion 5 for connecting the submarine cables 14A and 14B to each other at the submarine 2, and the submarine cable 14B floating in the sea interposed in the middle of the submarine cable 14B. An underwater buoy 6 to be connected, a pair of buoy mooring ropes 7A and 7B whose upper ends are anchored to the underwater buoy 6, a pair of anchors 8A and 8B for fixing the lower ends of the buoy mooring ropes 7A and 7B to the seabed 2, and an underwater buoy 6 is provided with a pair of cable bending limiting devices 9A and 9B that are attached to both side surfaces of the cable 6 and into which the submarine cable 14B is inserted.

  The platform 10 is provided with a power supply facility 11 at the top, and a portion extending from the power supply facility 11 to the seabed 2 is a circle for protecting the submarine cable 14A from drifting objects along the platform 10. A tubular protection member 12 is installed, and a submarine cable 14 </ b> A is inserted through the protection member 12.

  The underwater buoy 6 has, for example, a spherical shape, and has a structure that can float the submarine cable 14B. Cable bending limiting devices 9A and 9B are attached to both sides, and the cable bending limiting devices 9A and 9B are connected to the seabed. The cable 14B is inserted.

  The floating body 20 has a node portion 21 a that enables horizontal swinging, a support column 21 that is erected on the seabed 2, a floating unit 22 that is attached to the top of the support column 21, and a floating unit 22. Installed on the floating structure 24, the power receiving equipment 23 installed, the floating structure 24 that floats on the sea near the floating portion 22, the connecting member 25 that fixes the floating structure 24 to the column 21 so that it can float. And an electric cable 26 for connecting the electric device 26 to the power receiving facility 23, and a cable bending limiting device 9C that is attached to the lower surface of the floating portion 22 and limits the bending of the end of the submarine cable 14B.

Next, a method of connecting the power cables 14A and 14B employed for the submarine cable on the local sea will be described.
In FIG. 2, buoy mooring ropes 7A and 7B are connected to the underwater buoy 6 in advance. First, one end of the submarine cable 14 </ b> A is connected to the power supply facility 11 by the operator, and the other end of the submarine cable 14 </ b> A is pulled out to the seabed 2 through the protection member 12. On the other hand, the operator connects one end of the submarine cable 14B to the power receiving equipment 23 and passes the other end to the cable bending restricting devices 9A and 9B of the submarine buoy 6 that floats on the sea surface 3. The submarine buoy 6 is then connected to the submarine cable 14B. Set in the middle part. Next, the other end of the cable 14 </ b> B and the other end of the submarine cable 14 </ b> A are connected by the connecting portion 5 by the diver, and the connecting portion 5 is laid on the seabed 2. Further, connection between the power receiving facility 23 and the electric device 26 by the power cable 27 is performed by an operator. The order in which the submarine cables 14A and 14B are connected and then attached to the underwater buoy 6 may be used.

  After the underwater buoy 6 is attached to the submarine cable 14B, the anchors 8A and 8B are installed on the seabed 2 immediately below the underwater buoy 6, and then the underwater buoy 6 is submerged to a predetermined position in the sea, and the buoy mooring ropes 7A and 7B are anchored to the anchor 8A. , 8B and fix the underwater buoy 6.

In addition, an intermediate buoy is installed at the rising part of the long body in the sea. In this state, the intermediate buoy is submerged in the sea together with the long body, and the attachment of the intermediate buoy to the long body is easy on the sea surface. In addition, there is known a long body laying method that can be performed in advance on a work boat, on land, etc., and the workability of laying is improved. At this time, the long body and the connecting portion are laid on the seabed (see, for example, Patent Document 1).
JP-A-2-214404 (page 5-8, FIGS. 1 and 2)

  However, according to the conventional method for laying a long floating body for maritime floating bodies, the cable for supplying power and signals to the floating seafloor 20 has a floating portion 22 that moves vertically and horizontally by waves, winds, tides, etc. Even when laying with a catenary shape so as to reduce the influence, the submarine cable 14B between the underwater buoy 6 and the floating portion 22 is particularly subjected to large distortion. When the submarine cable 14B is damaged between the underwater buoy 6 and the floating portion 22, it is necessary to replace the entire length of the submarine cable 14B from the connection portion 5 with the submarine cable 14A. In this case, if the water depth is deep, a great amount of time and cost are required for lifting the submarine cable 14B. Similarly, in the method of Patent Document 1, replacement of the submarine cable after installation is not easy. Moreover, the connection part of cables cannot be provided in the part between the underwater buoy 6 and the floating part 22 to which a big distortion and tension | tensile_strength are applied to a cable.

  Therefore, an object of the present invention is to provide a long body for a floating body that can quickly replace a long body that has been damaged between a floating body and an underwater buoy, and a method for laying the long body.

In order to achieve the above object, the present invention provides a connecting portion provided on a relay member installed in the sea, with a long body laid from the land side and a long body laid from offshore facilities floating on the sea. Provided is a long body for a floating body, which is detachably attached via a cable.
Further, the present invention provides a method for laying a long body for a floating body of the sea, in which a long body such as a submarine cable is laid from a land side to a marine facility that floats on the sea via a relay member installed in the sea. A long floating body for a floating body over the sea, wherein the long body is formed from a plurality of long bodies, and the long bodies are detachably connected to each other at the connecting portion. Provide a method of laying.

  According to the long body for floating bodies of the sea and the laying method thereof according to the present invention, it is possible to quickly replace a long body damaged in the sea.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Composition of offshore facilities)
FIG. 1 shows a marine facility according to an embodiment of the present invention. This offshore facility 1 has the same configuration as that shown in FIG. 2, a platform 10 standing on the sea floor 2 near the land using a steel tower and the like, and a box installed offshore with the uppermost portion exposed from the sea surface 3. A ship-shaped marine floating body 20, two submarine cables 4A and 4B as long bodies laid in a state of being connected between the platform 10 and the marine floating body 20 via a connection portion 28, and the submarine cable 4A , 4B and a submerged buoy 6 as a relay member that floats in the vicinity of the connecting portion 28 in the sea, a pair of buoy mooring ropes 7A, 7B that are anchored at the upper end of the submerged buoy 6, and buoy mooring ropes 7A, 7B A pair of anchors 8A and 8B for fixing the lower end to the seabed 2 and a pair of cable bending limiting devices 9A and 9B attached to both side surfaces of the underwater buoy 6 and through which the seabed cables 4A and 4B are inserted. Further, a connecting portion 28 is detachably provided on the upper part of the underwater buoy 6 as a relay member.

  Although one submarine cable is formed by the submarine cables 4A and 4B, a plurality of submarine cables having the same configuration can be installed in parallel. In this case, one or a plurality of underwater buoys 6 are used according to the cable weight or the like, or the underwater buoys 6 are attached to each submarine cable.

The platform 10 has the same configuration as that of FIG. 2, and a power supply facility 11 such as a substation facility including a private power generation facility, a transformer and a circuit breaker is installed at the top, and the power supply facility 11 is connected to the seabed 2. A circular tubular protection member 12 is installed along the platform 10 to protect the submarine cable 4A from drifting objects and the like, and the cable 4A is inserted into the protection member 12.
In addition, although the platform 10 has shown the example installed in the sea, it is applicable also to the method of laying the submarine cable 4A to the general land.

  The underwater buoy 6 as a relay member has a spherical shape and has a material or structure that has buoyancy with respect to seawater. Cable bending restriction devices 9A and 9B are attached to both side surfaces and float in the sea. The cable bending restriction devices 9A and 9B prevent the bending from concentrating on only one point of each of the submarine cables 4A and 4B when the submarine cables 4A and 4B are started up from the sea and connected to the connection portion 28 on the submarine buoy 6. The shape of the cable is horn-shaped, and the submarine cables 4A and 4B are inserted inside. By connecting the submarine cables 4A and 4B to the cable bending limiting devices 9A and 9B, the connection portions 28 of the submarine cables 4A and 4B are fixed to the underwater buoy 6.

  The connection portion 28 has a structure that can prevent corrosion by seawater and the like, and a structure that can be separated from the underwater buoy 6, for example, fastening means such as bolts and nuts, and is divided into a platform 10 side and an ocean floating body 20 side. Two submarine cables 4A and 4B are connected and connected. In addition, although the connection part 28 was provided in the upper part of the underwater buoy 6, you may provide in the lower part of the underwater buoy 6 or the inside of the underwater buoy 6.

  The buoy mooring ropes 7A and 7B are made of nylon rope or the like that is strong against salt damage and has sufficient strength. Further, the anchors 8A and 8B are pile-shaped structures, ship anchors, and the like, and have a length or a weight that prevents the underwater buoy 6 from being washed away by a tidal current.

  The floating body 20 has the same configuration as that shown in FIG. 2, and includes a support column 21 made of an iron pillar or the like standing on the seabed 2 and a node portion 21 a that can swing in the horizontal direction and standing on the seabed 2. The supporting column 21, the floating unit 22 attached to the upper part of the supporting column 21, the power receiving equipment 23 installed in the floating unit 22, the floating structure 24 that floats on the sea near the floating unit 22, and the floating structure A connecting member 25 that fixes the shaft 24 to the column 21 so as to be swingable, an electric device 26 such as a motor and a pump installed on the floating structure 24, a power cable 27 that connects the electric device 26 to the power receiving facility 23, A horn-shaped cable bending limiting device 9C that is attached to the lower surface of the floating portion 22 and limits the bending of the submarine cable 4B.

(How to lay submarine cables)
Next, a method for laying the submarine cables 4A and 4B will be described. After constructing the platform 10 and the floating body 20, the power supply equipment 11 is installed on the platform 10, the power receiving equipment 23 is installed on the floating unit 22, and the electric device 26 is installed on the floating structure 24. Further, the power receiving facility 23 and the electric device 26 are connected by the power cable 27. The power cable 27 may be connected after the submarine cables 4A and 4B are laid.

  First, the operator inserts one end of the submarine cable 4 </ b> A through the protective member 12 and pulls it out to the seabed, and connects the other end to the power supply equipment 11. Further, after the underwater buoy 6 is levitated to the work site and one end of the submarine cable 4A pulled up from the seabed is passed through the cable bending restricting device 9A, a jig, a rope, etc. Then temporarily fix it to the underwater buoy 6.

  In addition, the operator passes one end of the submarine cable 4B from the lower side through the cable bending restriction device 9C and connects to the power receiving equipment 23, and the other end is inserted into the cable bending restriction device 9B from the lower side to connect one end of the connection portion 28. One end of the submarine cable 4B that has been temporarily fixed is connected to the other end of the connection portion 28. After the submarine cables 4A and 4B are connected to each other, the connecting portion 28 is attached and fixed to the upper portion of the underwater buoy 6 with bolts and nuts and fastened.

  Next, the underwater buoy 6 is moved to a predetermined position, submerged to a predetermined depth in the sea, the buoy mooring ropes 7A and 7B are engaged with the anchors 8A and 8B, and the underwater buoy 6 is positioned. Thus, the installation of the submarine cables 4A and 4B is completed.

Next, replacement when the submarine cable 4B is damaged will be described. First, the diver dives to the underwater buoy 6, loosens the bolts and nuts from the underwater buoy 6, removes the connecting portion 28, and moves the submarine cables 4 </ b> A and 4 </ b> B and the connecting portion 28 to the sea or near the sea surface. Next, only the submarine cable 4 </ b> B is removed from the connection portion 28, the cable bending restriction device 9 </ b> B, and the power receiving equipment 23. Next, another submarine cable 4B for exchange is prepared, one end thereof is connected to the power receiving equipment 23, and the other end is connected to one of the connection portions 28 through the cable bending limiting device 9B. Next, the other end of the connection portion 28 is fixed to the underwater buoy 6 with bolts and nuts by a diver and attached. The power cable 4A can also be replaced by the same method as the submarine cable 4B.
Moreover, the submarine cable 4B can be exchanged by floating the connecting portion 28 together with the underwater buoy 6.

(Effect of embodiment)
According to this embodiment, the following effects can be obtained.
(A) The damaged cable 4B can be quickly replaced between the floating body and the underwater buoy.
(B) By providing the connection portion 28 on the underwater buoy 6, it is not necessary for the diver to dive deep, and the burden on diving work can be reduced.
(C) Since the cables 4A and 4B can be connected to each other by the connecting portion 28 that has been removed from the underwater buoy 6 and moved to the sea or near the sea surface, laying becomes easy and the construction period can be shortened.
(D) Reconnecting can be facilitated by making the connecting portion 28 disassembleable.

[Other embodiments]
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. For example, as a relay member installed in the sea, instead of the sea buoy 6, a structure such as a pedestal that is installed in a fixed state on the bottom of the sea and is equipped with a connection portion 28 may be used. In this case, the connection portion 28 may be a structure that is still attached or a structure that can be disassembled, but it is desirable that the connection portion 28 be removable in consideration of workability by a diver.
Further, the shape of the relay member having a material or structure having buoyancy with respect to seawater may be various shapes such as a spherical shape, an elliptical shape, and a cylindrical shape.

  The power receiving equipment 23 may be installed on the floating structure 24 side, and the floating structure 24 may be connected to the upper end of the submarine cable 4B. In this configuration, the floating structure 24 may be moored using a large anchor or the like without using the column 21.

In addition to the submarine cable, the long body may be any of an optical cable, a communication cable, a control cable, various metal cables, and the like.
Furthermore, although there is a method of connecting two or more power cables directly at the local sea, the cables may be connected in advance at a power cable manufacturing factory in advance and connected by a continuous method.

It is an installation figure which shows the marine equipment which concerns on embodiment of this invention. It is an installation figure which shows the structure of the marine equipment using the conventional elongate body for maritime floating bodies.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Submarine equipment 2 Submarine 3 Sea surface 4, 4A, 4B Submarine cable 5 Connection part 6 Submarine buoy 7A, 7B Buoy mooring rope 8A, 8B Anchor 9A, 9B, 9C Cable bending restricting device 10 Platform 11 Power supply equipment 12 Protection member 20 Sea Floating body 21 Column 21a Node section 22 Floating section 23 Power receiving equipment 24 Floating structure 25 Connecting member 26 Electrical equipment 27 Power cable 28 Connection section 30 Offshore equipment

Claims (5)

  A long body laid from the land side and a long body laid from offshore facilities floating on the sea are detachably attached via a connecting portion provided on a relay member installed in the sea A long body for floating bodies.   The said floating member has the raw material or structure which has buoyancy with respect to seawater, The long body for floating bodies of the sea of Claim 1 characterized by the above-mentioned.   The long body for a floating body of the sea according to claim 1, wherein the connecting portion is provided on an upper portion of the relay member. In the method of laying a long body for a floating body of the sea, which lays a long body from the land side to a marine facility floating on the sea via a relay member installed in the sea,
A connecting part is installed on the relay member, the long body is formed from a plurality of long bodies, and the long bodies are detachably connected to each other by the connecting part. How to lay a scale.   The laying of a long body for a floating body of the sea according to claim 4, wherein, when the long body is replaced, the connecting portion is detached from the relay member and moved to or near the sea surface to be connected to the long body. Method.

Images