JP3201834B2 - Submarine laid long body burying method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for burying a long body laid on a seabed.

[0002]

2. Description of the Related Art When laying a submarine laid long body (a submarine cable, a submarine water pipe, a submarine oil supply pipe, a submarine gas pipe, etc.) on the seabed, in order to prevent the submarine laid long body from being damaged, the submarine laid long body. The body must be buried under the sea. As the burying method, a simultaneous laying and burying method in which seafloor excavation and burial are performed simultaneously, and a buried method in which a long seafloor laid long body is laid in advance on the seabed, and then the longfloor body is buried by digging the seabed There are two types. There are two types of excavators: a plow type burial machine and a water jet type burial machine.The former has the drawback that the traction force is larger than the latter, but it has the advantage that the excavation speed can be increased and the construction period is shortened. Is achieved. The burying method will be determined in consideration of the seabed soil and the size of the tide.

Next, a general embedding method using a water jet type embedding machine will be described with reference to FIG. As shown in FIG. 2, an anchor 2 is installed on the seabed at a position approximately 800 m in front of the laying boat 1, and a wire rope 3 for towing is laid from the anchor 2 to the laying boat 1.
While winding around the winch 4 installed above, attaching the burying machine 6 to the rear of the laying ship 1 via a cable guide or a tow wire rope 5 and winding the wire rope 3 with the winch 4, the towing machine 6 is pulled. The laying boat 1 is moved forward. The burying machine 6 excavates the seabed with a water jet, and moves forward while laying the submarine cable unwound from the laying ship 1 in the trench. In such a burial method, the laying ship 1
When the winder winds up the wire rope 3 and moves forward, the wire rope 3 rises from the seabed in a substantially straight line between the anchor 2 and the laying boat 1 due to tension, and the wire rope 3 becomes an obstacle near the laying boat 1. As a result, the navigation of other vessels 11 becomes impossible. Therefore, as shown in FIG. 3, a sinker 7 is attached in the middle of the tow wire rope 3 to reduce the floating range of the wire rope 3 when the laying ship is moving forward, and narrow the range of obstruction of navigation of the other ships 11. A construction method has been developed (see Japanese Patent Publication No. 58-33763).

[0004]

However, even with the improved method described above, it is not possible to narrow the floating range of the wire rope behind the laid ship, and to reduce the range of the ship's navigation obstruction. There was a limit.

[0005]

SUMMARY OF THE INVENTION The present invention provides a method of burying a submarine laid long body which solves the above-mentioned problems. The laid submarine laid long body boat and a seabed in front of the laid boat are provided. Connect the installed anchor with a tow wire rope,
The laying ship is advanced by winding the tow wire rope, and in the method of burying the submarine laying long body by the burying machine, the laying wire rope is wound from the anchor via the burying machine. The first aspect of the present invention is to take, and the second aspect of the present invention is to attach a counterweight to the burying machine in the above-mentioned aspect.

[0006]

As described above, when the tow wire rope is wound up from the anchor via the burial machine, the burial machine functions as a sinker, and the tow wire rope does not float on the sea surface of the laying ship. In addition, if an appropriate counterweight is attached to the burial machine as required, the burying machine can be prevented from floating and the traction force can be controlled.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is an explanatory view of one embodiment of the method of embedding a long seabed laid body according to the present invention. In the figure, the same reference numerals are used as in the description of the prior art. Reference numeral 8 denotes a counterweight having an appropriate weight which is attached to the burying machine 6 and prevents the buried machine 6 from floating. Reference numeral 9 denotes a submarine cable which is a long submarine cable laid on the seabed in advance. As shown, in this embodiment, the tow wire rope 3 is wound around the winch 4 from the anchor 2 via the counterweight 8 attached to the burying machine 6. Burial machine 6
The counterweight 8 is movably connected to the tow wire rope 3 via a pulley 10. The burying work is performed as follows. That is, when the tow wire rope 3 is wound around the winch 4, the laying ship 1 moves forward while dragging and moving the burying machine 6 and the counterweight 8 serving as a sinker, thereby excavating a trench on the seabed with the burying machine 6. The submarine laid elongated body 9 is buried in the groove. At this time, since the burying machine 6 and the counterweight 8 play the role of a sinker, the tow wire rope 3 does not rise in front of the laying boat 1. Further, since the burying machine 6 is located in front of the laying boat 1, the tow wire rope 3 does not float up behind the laying boat 1. Therefore,
The range of vessel obstruction has been significantly reduced compared to the past,
This is substantially the length of the laid boat 1. The burying method of the present invention can be applied to the simultaneous laying and burying method.

[0008]

As described above, according to the present invention, a laid marine vessel laid on a long seabed and an anchor installed on the seabed in front of the laid boat are connected by a tow wire rope,
The laying ship is advanced by winding the tow wire rope, and in the method of burying the submarine laying long body by the burying machine, the laying wire rope is wound from the anchor via the burying machine. Therefore, there is an excellent effect that the range of the ship's navigation is extremely reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory view of one embodiment of a method of burying a long seabed laid body according to the present invention.

FIG. 2 is an explanatory view of a conventional method of burying a long seabed laid long body.

FIG. 3 is an explanatory view of an improved burying method for a conventional long seabed laid long body.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laying ship 2 anchor 3, 5 wire rope 4 winch 6 burying machine 7 sinker 8 counterweight 9 submarine cable 10 pulley 11 ship

Claims (2)

(57) [Claims] 1. A laying boat having a long body laid on a seabed and an anchor installed on the seabed in front of the laying boat are connected by a towing wire rope, and the laying boat is advanced by winding the towing wire rope. A method for burying a long seafloor laid by a burying machine, wherein the tow wire rope is wound from an anchor via a burying machine. . 2. The method according to claim 1, wherein a counterweight is attached to the burying machine.