JP2001095123A - Post-embedding system and post-embedding method for subaqueous cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a post-embedding system and post-embedding method for subaqueous cable that can drastically improve the working efficiency and realize distinctive cost reduction by making unnecessary the monitoring and guiding works of a diver. SOLUTION: An embedding machine 14 for embedding a subaqueous cable 12 previously laid at the bottom 10 into a groove 10a dug at the bottom 10 comprises a monitoring under-water robot (ROV: Remotely Operated Vehicle) 18 having a function to monitor a towing ship 16 for towing the embedding machine 14 from the water surface, subaqueous cable 12 and the embedding machine 14 to transmit the monitoring information to the towing ship 16 and moving independently of the embedding machine 14 and towing ship 16 and a guiding controller 20 for moving the embedding machine 14 along the subaqueous cable 12, by operating the towing ship 16 and guiding the embedding in the predetermined route, based on the transmitted monitoring information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a post-burying system and a post-burying method for a submarine cable of a burying machine in which a submarine cable such as a submarine cable is previously installed on the bottom of the water, and the submarine cable is buried in the submarine with the burying machine.

[0002]

2. Description of the Related Art When burying a water bottom (sea bottom) cable, the cable is previously installed on the water bottom (sea bottom), a burial machine is attached to the cable, and the cable is installed in a trench excavated by the burial machine. There is a later burial method. In general, in the post-burial method, when the burial machine is mounted on the cable, as shown in FIG. 5, the underwater cable b is extended from the laying boat a so as to land, and the burial machine d is immersed in the water from the burying boat c. At this time, it is usual that the user is guided under inspection and monitoring by the diver e because of underwater, and the mounting operation is performed by handling the diver e.

[0003]

However, the work of mounting the burial machine to the cable b is performed by a diver underwater. However, when the diver is underwater (when the depth is more than 30 m),
There is a drawback that a saturated diving method is required, and the burden is large in terms of time and cost. In other words, in the saturated diving method, a living room that can adjust the pressure is installed on a barge above the water, and divers work on the seabed under high pressure in the living room. Heavy burden. Also, even in shallow seas, diver work takes time and may not be possible depending on sea conditions.

[0004] On the other hand, in the conventional post-burial method, a barge anchoring method has been adopted. In this type of barge anchoring method, as shown in FIG. 5, a buried barge c is anchored at a location about 300 m away on all sides (anchor buoy m), and a guard boat f and a lift anchor g are provided around the anchor. And also
In the vicinity, a transportation boat h and a work boat i are arranged, and in addition, a large fleet and a long construction period are required in order to tailor a barge j for saturation diving and each tugboat k and carry out post-burial work. For this reason, there was a problem that the construction cost became enormous.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and does not require a diver's monitoring and guidance work, thereby significantly improving work efficiency and achieving a significant cost reduction. Post-burial system and post-burial method.

[0006]

The present invention has the following arrangement to achieve the above object. The present invention relates to a burying machine for burying a submarine cable that has been settled on the bottom of a water floor, and a towing vessel for towing the burying machine from the water, and the submarine cable and the burying machine can be monitored underwater, and the monitoring information is provided. Underwater monitoring moving body that can be transmitted to the towing ship and can move independently from the buried machine and the towing ship, and based on the transmitted monitoring information, maneuver the towing ship and move the burying machine along the underwater cable, And a guidance control unit that guides the burying so as to follow a predetermined route. Further, in the present invention, the underwater monitoring moving body is a magnetic sensor that detects a pair of underwater cables from both sides thereof, an underwater television camera, a thruster that can be propelled in any direction, and various data signals and signals between the towing ship. And a signal transmission device for transmitting and receiving the control signal. Further, in the present invention, the towed vessel has a thruster capable of arbitrarily controlling the position of the hull on the water by generating a propulsive force in the direction of its side, a measuring device for measuring the position and orientation of the hull, and the measured position of the hull. An automatic position control device that automatically controls the thrust of the thruster based on the measurement result of the measuring device and automatically maintains the ship's position with respect to the set route when the heading deviates from the set route due to external force. Can be.

Further, according to the present invention, when burying a submarine cable settled on the bottom of the water by using a burying machine, the burying machine is towed from the water by a towing ship, and the submarine cable and the burying machine are connected to an underwater television camera. The underwater monitoring vehicle, which has a magnetic sensor and can move independently of the buried machine and the towing ship, monitors the vehicle and sends the monitoring information to the towing ship, and based on the transmitted monitoring information, steers the towing ship. This is a method of burying a submarine cable after moving the burying machine along the submarine cable and guiding the burying to a predetermined route.

According to the present invention, at the time of burying work after burying a submarine cable laid on the bottom of the water, the burying machine is towed from the water by a towing ship, and the submarine cable and the burying machine are separated from each other.
It is monitored by an underwater monitoring mobile unit that has an underwater television camera and a magnetic sensor and can move independently from the buried machine and the towing ship, and transmits the monitoring information to the towing ship. Based on the transmitted monitoring information, the towing ship To move the buried machine along the submarine cable and guide the burial to the specified route, so that the submarine cable and the buried machine are accurately monitored without the need for diving work by a diver. The burying work can be performed in accordance with the information, so that the monitoring and guiding work by the diver is not required, so that the work efficiency can be remarkably improved and a large cost reduction can be achieved.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory diagram of a submerged system and a submerged construction method of a submarine cable according to the present embodiment, FIG. 2 is an explanatory diagram of an underwater robot for monitoring underwater used in the system, and FIG. FIG. 4 is an explanatory diagram of the buried machine, and FIG. 4 is an explanatory diagram of control of the towing ship.

The underground system according to the embodiment shown in FIG.
Burying machine 14 in a trench 10a excavated in the water bottom 10
, A towing vessel 16 for towing the burying machine 14 from the water
And a function of monitoring the underwater cable 12 and the buried machine 14, transmitting the monitoring information to the towing vessel 16, and moving independently from the buried machine 14 and the towing vessel 16 (ROV: Remotely Operated). Vehicle) 18
And a guidance control device 20 for maneuvering the towing vessel 16 to move the burying machine 14 along the underwater cable 12 based on the transmitted monitoring information and guiding the burying to a predetermined route. It is.

The burying machine 14 is provided with a body having a sled-like bottom surface and a water jet type excavating body 14b inclined obliquely rearward and rearward from the main body 14a. The underwater cable 12 is installed and buried in a trench excavated by passing the underwater cable 12 through the excavation body 14b.

Also, as shown in FIG.
Has a pair of magnetic sensors 22 on the lower surface of the fuselage for detecting the underwater cable 12 from both sides thereof, and an underwater television camera 24 for monitoring the buried machine 14 and the underwater cable underwater with the tip of the fuselage. Provided at the rear end as needed, it can measure the attitude, altitude, and azimuth information of the aircraft. In the underwater ROV 18, a plurality of thrusters 26 that generate a propulsion force by a screw or the like and can direct the propulsion force in an arbitrary direction are provided at four corners of the fuselage in plan view, and various data signals and control are performed between the underwater ROV 18 and the towing ship 16. And a signal transmission device 28 for transmitting and receiving signals (for the ROV, see, for example, R & D News kansai 1998.9 371).

As shown in FIG. 3, the towing vessel 16 has a hull thruster 30 capable of arbitrarily controlling the attitude of the hull on the water by generating a propulsion force in any of the front, rear, left and right directions by a screw or the like. And gyrocompass and DG
A thruster of the thruster 30 is controlled based on a measurement result of the measuring device 32, such as a PS device, for measuring a position and a direction of the hull, such as a PS device, when the measured hull position and azimuth deviate from a set route due to an external force. Then, an automatic position control device (DPS: dynamic positioning system) 34 for automatically maintaining the ship position with respect to the set route is provided. In addition, as shown in FIG.
4 In addition to the automatic control (AUTO) by 4
The thruster 30 can also be manually controlled (manual) by operating the joystick according to the judgment of the master in No. 6.

A post-burying method using the post-burying system according to the embodiment will be described. When the underwater cable 12 previously settled on the water bottom is buried in the water bottom by the burying machine 14, the burying machine 10 is towed from the water by the towing boat 16. at the same time,
The underwater cable 12 and the buried machine 14 are provided by an underwater monitoring ROV 18 that can move independently of the buried machine 14 and the towing vessel 12.
Is photographed by the underwater television camera 24, the position of the underwater cable is detected by the magnetic sensor 22, and the monitoring information is transmitted to the towing ship 16 by the signal transmission device 28.

On the towing vessel 16, the towing vessel 16 is operated on the basis of the transmitted monitoring information, and the buried machine is connected to the submarine cable 1.
2 and guide the burial to a predetermined route. In this case, as shown in FIG. 3, the towing vessel 16 causes the burying machine 14 to move along the buried route by advancing the hull along the buried route in response to the crosswind and the waves. Since the operation is performed, the underwater cable 12 can be reliably buried along the target burying route.

According to the rear burying system and the rear burying method of the embodiment, since the burying machine 14 is moved along the underwater cable 12 and the burial is guided to a predetermined route, diving work by a diver is required. The submersible cable and the buried machine can be accurately monitored and buried in accordance with the monitoring information, so that divers do not need to monitor and guide the work, greatly improving work efficiency and achieving significant cost reductions. it can.

[0017]

As described above, according to the present invention, since the burying machine is moved along the underwater cable and the burying is guided to a predetermined route, the underwater cable can be connected to the underwater cable without the need for diving work by a diver. The burial machine can be accurately monitored, and the burying operation can be performed according to the monitoring information. Therefore, the monitoring and guidance work by the diver is not required, and the work efficiency can be remarkably improved, and a significant cost reduction can be achieved. In addition, the basic fleet is a towing vessel, except for patrol vessels and passing vessels. Therefore, the fleet has a simple fleet configuration, and in this respect significant cost reduction can be achieved. In addition, since the condition of the buried machine and the cable can be monitored by the underwater monitoring moving body, the quality control of the cable is improved. In addition, obstacles ahead can be quickly found by the underwater monitoring moving object. In addition, if the towed vessel is equipped with a thruster, a hull position and heading measurement device, and an automatic position control device that controls the thrust of the thruster and automatically maintains the ship's position, hovering on the ocean is possible. And the landing of the burial machine,
Lifting can be done without anchoring. Unlike the burial method using anchoring, continuous work is possible day and night, and fragrance can be significantly reduced (cost reduction).

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a rear buried system according to an embodiment of the present invention.

FIGS. 2A and 2B are a front view and a plan view illustrating an underwater monitoring ROV.

FIG. 3 is an explanatory diagram of the behavior of the buried machine of the towing ship during towing.

FIG. 4 is an explanatory diagram of each automatic and manual control of the towing ship.

FIG. 5 is an explanatory diagram of a conventional diver's burial machine guiding operation.

FIG. 6 is an explanatory view of a conventional anchoring method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Underwater 12 Underwater cable 14 Buried machine 16 Towing ship 18 ROV for underwater monitoring 20 Guidance control device 22 Magnetic sensor 24 Underwater television camera 26 Thruster 28 Signal transmission equipment 30 Hull thruster

Claims (4)

[Claims] 1. A buried machine for burying a submarine cable settled on the bottom of a water floor in the bottom of the water, a towing ship for towing the buried machine from the water, a submarine cable and the buried machine can be monitored underwater, and the monitoring information is provided. A mobile object for underwater monitoring that can transmit to the towing ship and move independently from the buried machine and the towing ship, and based on the transmitted monitoring information, maneuvers the towing ship and moves the buried machine along the submarine cable. And a guidance control unit for guiding the burying so as to be a predetermined route. The underwater surveillance moving body includes a magnetic sensor for detecting a submarine cable from both sides of the underwater cable, an underwater television camera, a thruster capable of propulsion in an arbitrary direction, and various data signals and controls between a towed ship. The system according to claim 1, further comprising a signal transmission device for transmitting and receiving signals. 3. A towed ship has a thruster capable of arbitrarily controlling the attitude of the hull above the water by generating a propulsive force in the side of the ship, a measuring device for measuring the position and azimuth of the hull, An automatic position controller that automatically controls the thrust of the thruster based on the measurement results of the measurement device and automatically maintains the ship's position with respect to the set route when the heading deviates from the set route due to external force is provided. The submerged cable system according to claim 1 or 2, wherein 4. When burying a submarine cable that has landed on the bottom of the water with a buried machine, the buried machine is towed from the surface of the water by a towing ship, and the submarine cable and the buried machine are equipped with an underwater television camera and a magnetic sensor. And monitoring by the underwater monitoring mobile unit that can move independently from the buried aircraft and the towing vessel, transmits the monitoring information to the towing vessel, and based on the transmitted monitoring information, steers the towing vessel and A method of post-burying a submarine cable, wherein the submarine cable is moved along a submarine cable and the burial is guided to a predetermined route.