JP2020014330A - Method for burying submarine cable - Google Patents

Abstract

To provide a method for burying a submarine cable that can simplify a burying device and preparation for installing the same, and shorten a burying time to reduce burying costs.SOLUTION: A seabed cutting device 10 includes: a device body 20 having a plurality of wheels W and provided to be travelable on a seabed surface B; and a sea chain-saw (bottom cutting unit) 40 having a saw chain (blade) 43 for cutting the seabed surface B and fixedly supported on the device body 20. The method for burying a submarine cable C includes: a first cutting step of cutting the seabed surface B with the chain-saw 40 of the seabed cutting device 10 to form a first cut part S on one side of the submarine cable C in the width direction; and, after the first cutting step, a second cutting step of cutting the seabed cutting seabed surface B with the chain-saw 40 of the seabed cutting device 10 to form a second cut part S on the other side of the submarine cable C in the width direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for burying a submarine cable.

  As a conventional method of burying a submarine cable, there is known a method of using a submarine work tractor which is configured to be able to run on the sea floor and has a wire burying ski attached via a hydraulically operated arm (for example, Patent Document 1). reference). This undersea work tractor excavates the seabed and draws and embeds the submarine cable from the line-laden barge on the surface of the sea on which the line coil is mounted via the control unit and the control cable. It is configured to pull a barge.

  As another embedding method, a method using an embedding machine having a water jet type excavation body is known (for example, see Patent Document 2). This excavation body is provided in the length direction longer than the width, and a plurality of water jet nozzles are arranged on the lower surface thereof. Further, the excavated body has a structure that can be slidably and submerged on the sea bottom so as to be swingable with respect to the burying machine main body, and a plurality of water supply passages are provided inside the excavated body. The plurality of water supply passages are individually communicated with each set of water jet nozzles divided into a plurality of sets in the length direction of the excavated body.

JP-A-5-3615 JP 2000-13947 A

  However, in the embedding methods of Patent Documents 1 and 2, the apparatus is large-scale and the embedding cost is increased. Specifically, in the method of Patent Literature 1, excavation of the sea bottom is performed by excavating with a wire burying ski of a submarine work tractor. Further, in Patent Document 2 described above, the operation is performed with the buried body of the water jet buried in the sea bottom, and the sea bottom is excavated by the water pressure.

  As described above, the conventional embedding method uses an apparatus having a complicated mechanism. Therefore, handling is difficult, for example, the preparation of the mechanism requires preparation, and the mechanism is expensive, resulting in an increase in the burying cost.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to simplify a burying device and installation preparation thereof, and to shorten a burying time and reduce a burying cost. An object of the present invention is to provide a cable burying method.

The above object of the present invention is achieved by the following configurations.
(1) A method of burying a submarine cable by cutting a seabed using a submarine cutting device, wherein the submarine cutting device has a plurality of wheels and is provided so as to be able to run on the seabed. A state in which a submarine cable has a blade for cutting the sea bottom and is fixed and supported by the apparatus main body, and the submarine cable is temporarily placed substantially linearly on the sea bottom. Or a submarine cable cutting apparatus with a predetermined widthwise gap between the submarine cable and the blade of the submarine cable cutting section on one side in the width direction of the submarine cable with respect to the planned location of the submarine cable on the seabed. A first cutting in which the main body is caused to travel a predetermined distance along a longitudinal direction of the submarine cable, and the submarine cutting section of the submarine cutting device cuts the seabed to form a first cutout on one side in the width direction of the submarine cable. And after the first cutting step, the submarine cable The other side in the direction, the main body of the submarine cutting device travels a predetermined distance along the longitudinal direction of the submarine cable, leaving a predetermined width direction gap between the submarine cable and the blade of the submarine cutting section, and runs the submarine cutting device. A second cutting step of cutting the sea bottom at the submarine cutting section to form a second cut section on the other side in the width direction of the submarine cable, and the first and second cutting steps performed by the first and second cutting steps. A removing step of forming a storage groove along the longitudinal direction of the submarine cable by removing a portion sandwiched between the cuts, and a burying step of burying the submarine cable in the storage groove formed by the removing step. A method of burying a submarine cable, comprising:
(2) In the case where the first cutting step is performed in a state where the submarine cable is temporarily placed substantially linearly on the seabed, after the first and second cutting steps, the submarine cable is connected to the seabed. The method of embedding a submarine cable according to (1), further comprising a retreating step of retreating temporarily so as not to overlap the first and second cut portions and the intervening portion on the surface.
(3) The method of embedding a submarine cable according to (1) or (2), wherein the submarine cutting section of the submarine cutting device is a hydraulic chain saw.

  According to the method of embedding a submarine cable of the present invention, the submarine cutting device has a plurality of wheels, a device main body provided to be able to run on the sea bottom, and a blade for cutting the sea bottom, the device A submarine cutting section fixedly supported by the main body, and in a state where the submarine cable is temporarily placed substantially linearly on the seabed, or with respect to a position where the submarine cable is to be buried on the seabed, One side in the width direction of the cable is separated by a predetermined width direction gap between the submarine cable and the blade of the submarine cutting section, and the apparatus main body of the submarine cutting device is caused to travel a predetermined distance along the longitudinal direction of the submarine cable, and the submarine A first cutting step of cutting a sea bottom at a submarine cutting section of a cutting device to form a first cutout on one side in a width direction of the submarine cable, and after the first cutting step, the other in the width direction of the submarine cable. Side between the submarine cable and the blade of the submarine cut The main body of the submarine cutting device is caused to travel a predetermined distance along the longitudinal direction of the submarine cable with a gap in the width direction, and the seabed is cut at the submarine cutting portion of the submarine cutting device. (2) a second cutting step for forming a notch, and a portion between the first and second cuts cut by the first and second cutting steps is removed, and the longitudinal direction of the submarine cable is removed. And a burying step of burying a submarine cable in the storage groove formed by the removing step. For this reason, the burying device and its installation preparation can be simplified, the burying time can be shortened, and the burying cost can be reduced.

  The present invention has been briefly described above. Further, details of the present invention will be further clarified by reading through the modes for carrying out the invention described below (hereinafter, referred to as “embodiments”) with reference to the accompanying drawings.

FIG. 1 is a perspective view illustrating a submarine cutting apparatus according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a schematic diagram illustrating a first stage of a submarine cable embedding process using the submarine cutting device illustrated in FIG. 1. FIG. 4 is a schematic diagram illustrating a second stage of a submarine cable embedding process using the submarine cutting device illustrated in FIG. 1.

Hereinafter, an embodiment of a method for burying a submarine cable according to the present invention will be described in detail with reference to the drawings.
In the following description, the direction in which the vehicle travels with respect to the seabed cutting device is referred to as the front-back direction of the device. On a plane parallel to the apparatus running surface (sea bottom), that is, on a horizontal plane, a direction orthogonal to the front-rear direction of the apparatus is defined as the apparatus width direction. In this apparatus width direction, the left side of the apparatus in the front-rear direction is the apparatus left side, and the right side is the apparatus right side. The longitudinal direction of the device is parallel to the longitudinal direction of a submarine cable described later. In the seabed cutting device, the front and rear of the device and the width direction of the device are parallel to a horizontal plane, the vertical direction is a vertical direction perpendicular to the horizontal plane, and is parallel to the direction in which gravity acts.

<Seabed cutting device>
First, a seabed cutting device 10 according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view illustrating a submarine cutting apparatus 10 according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of FIG.

  In addition, the submarine cutting apparatus 10 of this embodiment cuts the seabed B as a process before embedding the submarine cable C in the seabed. In the present embodiment, an optical fiber cable is described as an example of the submarine cable C, but the present invention is not limited to this. Other than that, the type of the cable or installation object laid on the sea floor is not limited.

As shown in FIGS. 1 and 2, the sea bottom cutting device 10 is a vehicle having four wheels W, and is provided with a device main body 20 provided to be able to run on a sea bottom B, and fixedly supported by the device main body 20. (Seabed cutting part) 40.
In addition, the apparatus main body 20 of the seabed cutting apparatus 10 is mainly formed of a metal member, and many of the respective parts described below are integrally provided by welding or the like.

  The device main body 20 has a plurality of device frames 21 forming a skeleton of the device main body 20. The device frame 21 is formed in a substantially frame shape, and is provided with a base frame 22 disposed along a device traveling surface such as a sea bottom B at intervals in the vertical direction of the device, and a device at a front end of the base frame 22. A pair of front frames 33, 33 arranged at intervals in the width direction and extending in the vertical direction of the device, and a pair of front frames 33, 33 arranged at intervals at the rear end of the base frame 22 in the width direction of the device to extend in the vertical direction of the device. A pair of extending rear frames 35, 35, a front handle 34 connecting the front ends of the pair of front frames 33, 33, a rear handle 36 connecting the front ends of the pair of rear frames 35, 35, It is comprised including.

The base frame 22 includes a first rectangular frame 23 disposed obliquely with respect to a horizontal plane when viewed from the side, and a first frame 23 which is disposed between the first frame 23 and a portion of the first frame 23 which is closest to the apparatus running surface (sea bottom). A second rectangular frame 30 that is vertically spaced apart from the first frame 23 is erected at the front end of the first frame 23, and the leading end is connected to the rear end of the second frame 30. And a pair of left and right walls 32, 32.
The pair of left and right walls 32 is fixedly connected to the front end of the side of the first frame 23 at the base end of each wall 32 and the front end of a connection frame 24 described later, respectively. The front end of the body 23 and the rear end of the second frame 30 are connected in a step (step) manner. That is, the base frame 22 is formed in a substantially Z shape in a side view.

  The first frame body 23 extends in the front-rear direction of the apparatus within the frame, and is provided with a pair of left and right connection frames 24, 24 arranged at an interval in the apparatus width direction. And a bridge frame (not shown) that is disposed so as to bridge an intermediate portion of the frames 24, 24 in the front-rear direction of the apparatus.

The pair of left and right connection frames 24 are connected to the rear end of the first frame 23 at the rear end of the connection frame 24, respectively. The pair of left and right connecting frames 24, 24 are disposed in parallel with the left and right sides of the first frame 23, that is, obliquely with respect to the horizontal plane in side view. In the space between the left connecting frame 24 and the left side of the first frame 23, the left front wheel W and the rear wheel W are rotatably supported side by side in the front-rear direction of the apparatus. Further, on the left side of the left connecting frame 24 and the left side of the first frame 23, there are disposed shaft supporting portions 25 for supporting the rotating shafts (not shown) of the left front wheel W and the rear wheel W, respectively. Similarly, a right front wheel W and a rear wheel W are juxtaposed in the space between the right connecting frame 24 and the right portion of the first frame body 23 in the front-rear direction of the device. It is rotatably supported by the part 25.
Each of the outer peripheral surfaces of the tires of the four wheels W is recessed inward in the radial direction and formed in a concave shape. In addition, a partition bracket 26 that horizontally spans the connection frame 24 and the side of the first frame 23 is disposed between the left and right front and rear wheels W.

  The bridge frame is a reinforcing member for the pair of left and right connection frames 24, 24, and improves the rigidity of the entire first frame 23. A saw body 41 (to be described later) of the chain saw 40 is disposed above the bridge frame, and the bridge frame supports the saw body 41 of the chain saw 40 via a pair of left and right connection frames 24, 24 or the sea floor. The saw body 41 of the chainsaw 40 is protected from soaring soil and gravel when the surface B is cut.

  A fan-shaped saw fixing jig 27 is erected in the middle of the left connecting frame 24 in a side view. The saw fixing jig 27 is made of a metal plate member, and has a plurality of bolt insertion holes 28 formed at substantially equal intervals along the circumferential direction on the outer edge. The saw fixing jig 27 is used to fix and support the chainsaw 40 to the apparatus main body 20 at an arbitrary mounting angle, as described later.

  A guard portion 31 having a mesh shape is provided on the inner frame of the second frame 30 so as to be adhered to one surface. The card unit 31 protects the operator of the seabed cutting device 10 from rocks, gravel, and the like that fly when the seabed B is cut.

The chainsaw 40 is a hydraulic chainsaw, and includes a saw body 41 having a built-in hydraulic power source, a guide bar 42 held by the saw body 41, and a saw chain drivably arranged on the outer periphery of the guide bar 42. The blade includes a (blade) 43, a sprocket 44 that is rotated by a hydraulic power source to drive the saw chain 43, and a throttle lever 45 that allows the rotation of the hydraulic power source to be arbitrarily adjusted. Further, a support bracket 46 for attaching to the saw fixing jig 27 is fixed to the saw body 41 with a plurality of bolts.
A hydraulic hose H is connected to the saw body 41, and hydraulic pressure is supplied from outside (for example, from the ground) as a power source. Further, the throttle lever 45 is fixedly supported by the rear handle 36, so that the operator can rotate the chain saw 40 while pressing the apparatus main body 20 of the submarine cutting apparatus 20. Further, a bolt screw hole (not shown) is formed in the support bracket 46.

A bolt is inserted into one of the plurality of bolt insertion holes 28 of the saw fixing jig 27, and the bolt is screwed into a bolt screw hole of the support bracket 46 of the chain saw 40. Thereby, the chainsaw 40 is fixedly supported by the apparatus main body 20 at a predetermined mounting angle (inclination angle with respect to the running surface).
When changing the attachment angle of the chainsaw 40, the bolt insertion hole 28 into which the bolt is screwed may be appropriately selected.

  The seabed cutting device thus configured is submerged in the sea and placed on the seabed B as shown in FIG. Then, the operator grips the rear handle 36 of the seabed cutting device 10 and pushes the device main body 20 toward the front of the device to run. When an assistant is involved in the operation, the assistant grasps the front handle 34 of the apparatus main body 20 and performs steering adjustment of the apparatus main body 20 in the traveling direction. Further, the operator operates the throttle lever 45 attached to the front handle 34 while traveling the apparatus main body 20 to adjust the operation / stop, rotation speed, and the like of the chainsaw 40, and cut the sea bottom B.

  However, in the initial state of the sea bottom cutting, the chainsaw 40 is not properly inserted into the sea bottom B. Therefore, the chainsaw 40 is rotationally driven while the rear wheels are running in a state where only the front wheel W of the seabed cutting device 10 is separated (floated) from the seabed B by the operator and the assistant. Then, the front wheel W is gradually approached to the sea bottom B, and the saw chain 43 of the chainsaw 40 is inserted into the sea bottom B. When the front wheel W comes into contact with the sea bottom B, the operator and the assistant push the apparatus body 20 along the sea bottom B to run. At this time, the chainsaw 40 fixed and supported by the apparatus main body 20 cuts (cuts) the sea bottom B to form a cut portion S in the sea bottom B (see FIGS. 3 and 4). As a result, the notch S is formed to extend in the traveling direction of the device main body 20.

<Method of burying submarine cable of this embodiment>
Next, a method of embedding the submarine cable C of the present embodiment will be described with reference to FIGS. FIG. 3 is a schematic diagram illustrating a first stage of a submarine cable C burying process using the submarine cutting device 10 of the present embodiment. Drawing 4 is a mimetic diagram explaining the latter stage of a burying process of submarine cable C using submarine cutting device 10 of this embodiment.

As shown in FIG. 3 (A), first, the cable is temporarily placed on the seabed B at the position where the submarine cable C is to be buried (that is, the placing step). At the time of mounting, the submarine cable C is mounted substantially linearly so as not to be entangled on the seabed B. Further, the burying of the submarine cable C of the present embodiment is preferably performed in a sea area with a water depth of less than 30 m.
It is to be noted that, without actually placing the submarine cable C, the position where the submarine cable C is to be buried on the seabed B may be dealt with using a marker or the like. For example, a tape may be placed as a dummy marker of the submarine cable C, or a planned burial position may be cut or excavated with a chain saw 40 or an excavator to perform marking.

As shown in FIG. 3B, in a state where the submarine cable C is temporarily placed on the submarine bottom B, the submarine cable C is located on one side in the width direction of the submarine cable C (in FIG. The seabed cutting device 10 is installed so that a predetermined widthwise gap is formed between C and the saw chain (blade) 43 of the chainsaw (seabed cutting portion) 40 (see FIGS. 1 and 2). Then, the operator or the like makes the apparatus main body 20 of the submarine cutting device 10 travel a predetermined distance along the longitudinal direction of the submarine cable C, and cuts the submarine bottom B with the chainsaw 40 of the submarine cutting device 10. Thereby, the first cut portion S is formed on one side in the width direction of the submarine cable C along the longitudinal direction of the submarine cable C (that is, a first cutting step).
Note that the depth of the notch S is preferably about 30 cm.

  As shown in FIG. 3C, similarly to the first cutting step, on the other side in the width direction of the submarine cable C (in FIG. 3, the front side in the drawing), the submarine cable C and the saw chain 43 of the chain saw 40 are connected. The seabed cutting device 10 is installed so that a predetermined gap in the width direction is formed therebetween (see FIGS. 1 and 2). Then, the seabed cutting device 10 is caused to travel a predetermined distance, and the sea bottom B is cut by the chainsaw 40 of the seabed cutting device 10. Thereby, the second cut portion S is formed on the other side in the width direction of the submarine cable C along the longitudinal direction of the submarine cable C (that is, the second cutting step). The size between the first and second cuts S may be set to, for example, 20 cm to 30 cm in accordance with the diameter of the submarine cable C.

  As shown in FIG. 4A, after the first and second cutting steps, the submarine cable C is connected to the first and second cuts S, S, and the first and second cuts on the seabed B. Specifically, the second cut portion S is temporarily retracted to the other side in the width direction (the front side in FIG. 4) so that none of the portions P sandwiched between the portions S, S overlap. (Ie, evacuation process).

As shown in FIG. 4 (B), after the evacuation process, a portion P sandwiched between the first and second cuts S, S is excavated using an excavator or the like. Further, during this period, gravel and the like are swept out of the portion P using the water flow of the jet pump. Thus, the inter-portion P is removed to form the storage groove G along the longitudinal direction of the submarine cable C (that is, the removing step).
In addition, it is not limited to an excavator or a jet pump, and various machines can be used as long as the inter-portion P can be removed.

  As shown in FIG. 4C, after the storage groove G is formed in the removing step, the submarine cable C is stored in the storage groove G. With the submarine cable C stored in the storage groove G, the storage groove G is appropriately filled with gravel, underwater concrete (not shown), or the like, and the submarine cable C is buried in the sea floor B.

<Advantages of this embodiment>
As described above, according to the method of embedding the submarine cable C according to the present embodiment, the submarine cutting device 10 includes the device main body 20 that has the plurality of wheels W and is provided so as to be able to run on the submarine bottom B. A chain saw (blade) 40 that has a saw chain (blade) 43 for cutting the surface B, and is fixedly supported by the apparatus main body 20; In a state where the submarine cable C is temporarily placed, one side of the submarine cable C in the width direction is separated from the submarine cable C and the saw chain 43 of the chain saw 40 by a predetermined width direction, and the apparatus body 20 of the submarine cutting device 10 is separated. Is moved a predetermined distance along the longitudinal direction of the submarine cable C, and the submarine bottom B is cut by the chainsaw 40 of the submarine cutting device 10 to form the first cut portion S on one side in the width direction of the submarine cable C. Cutting process 1 After the cutting step, the other side of the submarine cable C in the width direction is separated from the submarine cable C and the saw chain 43 of the chain saw 40 by a predetermined width direction, and the apparatus body 20 of the submarine cutting apparatus 10 is connected to the submarine cable C. A second cutting step of cutting the sea bottom B with the chainsaw 40 of the sea floor cutting device 10 to form a second cut S on the other side in the width direction of the sea floor cable C by running a predetermined distance along the longitudinal direction of the sea floor cutting device 10 And the portion P interposed between the first and second cut portions S, S cut in the first and second cutting steps is removed, and the storage groove G along the longitudinal direction of the submarine cable C is removed. The method includes a removing step of forming and a burying step of burying the submarine cable C in the storage groove G formed by the removing step. For this reason, the burying device and its installation preparation can be simplified, the burying time can be shortened, and the burying cost can be reduced.

  In addition, according to the method of embedding the submarine cable C of the present embodiment, since the process (operation) is mainly performed manually, it is possible to cut or excavate the seabed B while visually checking the state of embedding of the submarine cable C. is there. For this reason, it is not necessary to cut or excavate more than necessary, and the work efficiency can be improved.

  Further, according to the method of embedding the submarine cable C of the present embodiment, the chainsaw 40 is fixedly supported by the apparatus main body 20, so that there is no need for an operator or the like to directly work with the chainsaw 40. For this reason, since the blade edge of the chainsaw 40 is separated from the operator's hand, work safety can be improved. Further, since the sea bottom cutting device 10 has a simple structure and is lightweight, it can be mounted on a small boat, and in this case, the burying cost can be further reduced.

  Further, according to the method of embedding the submarine cable C of the present embodiment, after the first and second cutting steps, the submarine cable C is connected to the first and second cutouts S, S and the intermediate portion on the seabed B. Since the method further includes a retreating step of temporarily retreating so as not to overlap with P, the embedding time can be further reduced, and the working efficiency can be improved.

  Here, conventionally, there was no excavation using a chainsaw in water. The hydraulic chainsaw itself was never used for underwater use. However, according to the method of embedding the submarine cable C of the present embodiment, since the submarine cutting unit 40 of the submarine cutting device 10 is a hydraulic chain saw, the embedding device can be simplified and the embedding cost can be further reduced.

  The method of embedding the submarine cable C of the present embodiment may be used in a soft rock portion or a shallow sea area on the seabed B. In this case, a significant reduction in burial costs is expected.

  Note that the present invention is not limited to those exemplified in the above embodiment, and can be appropriately changed without departing from the gist of the present invention. For example, in the above embodiment, the chainsaw (40) is adopted as the seabed cutting part, but the present invention is not limited to this. For example, a hydraulic hand cutter (circular saw) having a disk-shaped rotating wheel as a blade may be employed. 2. Description of the Related Art A hydraulic hand cutter rotates a rotating wheel at a high speed and cuts an object at a periphery of the rotating wheel.

DESCRIPTION OF SYMBOLS 10 Submarine cutting apparatus 20 Device main body 21 Device frame 22 Base frame 23 1st frame 24 Connection frame 25 Shaft support 26 Partition bracket 27 Saw fixing jig 28 Bolt insertion hole 30 2nd frame 31 Guard part 32 Wall part 33 Front Frame 34 Front handle 35 Rear frame 36 Rear handle 40 Chainsaw (seabed section)
41 Saw body 42 Guide bar 43 Saw chain 44 Sprocket 45 Throttle lever 46 Support bracket B Sea bottom S Notch P Intersection G Storage groove C Submarine cable W Wheel H Hydraulic hose

The above object of the present invention is achieved by the following configurations.
(1) A method of burying a submarine cable by cutting a seabed using a submarine cutting device, wherein the submarine cutting device has a plurality of wheels and is provided so as to be able to run on the seabed. A state in which a submarine cable has a blade for cutting the sea bottom and is fixed and supported by the apparatus main body, and the submarine cable is temporarily placed substantially linearly on the sea bottom. in the one side in the width direction of the submarine cable, predetermined distance traveling apparatus main body of the submarine cutting device at a predetermined width direction gap along the longitudinal direction of the submarine cable between the blades of submarine cables and submarine cutting portion A first cutting step of cutting a sea bottom at a submarine cutting section of the submarine cutting apparatus to form a first cutout on one side in a width direction of the submarine cable; The other side in the width direction of the seabed cable and the blade of the seabed cutting part. The main body of the submarine cutting device is caused to travel a predetermined distance along the longitudinal direction of the submarine cable with a predetermined widthwise gap therebetween, and the submarine cutting section of the submarine cutting device cuts the seabed to cut the other side in the widthwise direction of the submarine cable. After the second cutting step of forming a second cutout on the side and the first and second cutting steps, the submarine cable is connected to the first and second cutouts on the seabed, and the first and second cutouts are formed. A retreating step of temporarily retreating so as not to overlap with an intervening portion sandwiched between the first and second cut portions cut by the cutting process, and after the retreating process , removing the intervening portion to remove the submarine cable. A method for burying a submarine cable, comprising: a removing step of forming a storage groove along a longitudinal direction; and a burying step of burying a submarine cable in the storage groove formed by the removing step.
(2) The method of embedding a submarine cable according to (1), wherein the submarine cutting section of the submarine cutting device is a hydraulic chain saw.

According to the method of embedding a submarine cable of the present invention, the submarine cutting device has a plurality of wheels, a device main body provided to be able to run on the sea bottom, and a blade for cutting the sea bottom, the device comprising a submarine cutting portion which is fixedly supported by the body, and in a state in which the submarine cable is temporarily placed substantially linearly on the seafloor, the one widthwise side of the submarine cable, submarine cable and the seabed cutting The main body of the submarine cutting device is run for a predetermined distance along the longitudinal direction of the submarine cable, leaving a predetermined width direction gap between the blade of the part, and cutting the seabed at the submarine cutting part of the submarine cutting device. A first cutting step of forming a first notch on one side in the width direction of the submarine cable, and after the first cutting step, the other side in the width direction of the submarine cable is connected to the submarine cable and the blade of the submarine cutting section. Leave the main body of the submarine cutting device at the bottom of the By a predetermined distance to travel along the longitudinal direction of Buru, a second cutting step of forming a second cut portion by cutting the seabed at seabed cutting portion of the seabed the cutting device in the other widthwise side of the submarine cable, After the first and second cutting steps, the submarine cable is sandwiched between the first and second cut sections on the sea floor and the first and second cut sections cut by the first and second cutting steps. A retreating step of temporarily retreating so as not to overlap with the interposed portion, a removing step of removing the interposed portion after the retreating process to form a storage groove along the longitudinal direction of the submarine cable, Burying a submarine cable in the formed storage groove. For this reason, the burying device and its installation preparation can be simplified, the burying time can be shortened, and the burying cost can be reduced.

Claims (3)

A method of burying a submarine cable in which a submarine cable is buried by cutting a seabed using a submarine cutting device,
The seabed cutting device has a plurality of wheels, a device main body provided to be able to run on the sea bottom, and a blade for cutting the sea bottom, and a sea bottom cutting fixed and supported by the device main body. And a part,
In the state in which the submarine cable is temporarily placed substantially linearly on the submarine, or with respect to the planned location of the submarine cable on the submarine, the width direction one side of the submarine cable, A predetermined width direction gap is provided between the submarine cable and the blade of the submarine cutting section, and the apparatus main body of the submarine cutting apparatus is caused to travel a predetermined distance along the longitudinal direction of the submarine cable, and the submarine cutting apparatus has A first cutting step of cutting the sea bottom with the submarine cutting section to form a first cut section on one side in the width direction of the submarine cable;
After the first cutting step, the other side of the submarine cable in the width direction is provided with a predetermined width direction gap between the submarine cable and the blade of the submarine cutting section, and the apparatus main body of the submarine cutting apparatus is opened. The submarine cable is driven a predetermined distance along the longitudinal direction, and the submarine cutting section of the submarine cutting device cuts the submarine bottom to form a second cut section on the other side in the width direction of the submarine cable. 2 cutting steps;
Removing a portion between the first and second cut portions cut by the first and second cutting processes to form a storage groove along a longitudinal direction of the submarine cable; ,
A burying step of burying the submarine cable with respect to the storage groove formed by the removing step,
A method of burying a submarine cable, comprising: In a case where the first cutting step is performed in a state where the submarine cable is temporarily placed substantially linearly on the seabed,
After the first and second cutting steps, the method further includes a retreating step of temporarily retreating the submarine cable so that the submarine cable does not overlap the first and second cuts and the intervening portion on the seabed. The method of burying a submarine cable according to claim 1, wherein:   The method of burying a submarine cable according to claim 1, wherein the submarine cutting section of the submarine cutting device is a hydraulic chain saw.

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