JPS5924609B2 - Method for burying long objects on the seabed in shallow waters - Google Patents

Description

[Detailed Description of the Invention] Places where long submarine bodies (submarine cables, water pipes, etc.) are unloaded are often so shallow that construction ships cannot enter.

Therefore, when unloading a long body, a method is used in which a buoy is attached to the long body sent out from a laying ship, and the long body is buoyed at sea and then hauled to land.

The present invention relates to a method for burying a long body that has been landed.

Conventional burial method 1) After pulling the elongated body onto land as described above, the buoy is removed and the elongated body is sunk into the seabed.

2) Bury it using a burying machine.

"Figures 1 and 2" show the burial situation.

10 is a towing ship (laying ship), 12 is a sheave, and 14 is a long body.

Attach a wire 18 to the burial machine 16 and connect it to the towing vessel 10.
It is towed by the winch 20 above.

22 is land. Problem ■) The towing boat 10 cannot approach the land 22 because the water is deep.

Therefore, the burial machine 16 has to be towed from a very far distance.

If the burying machine 16 is towed from a distance, it becomes difficult to move the burying machine 16 along the elongated body 14.

When the burying machine leaves the elongated body, the elongated body 14 moves to the burying machine 16.
There is also the risk that the cable may hit the inlet 17 of the cable and cause excessive bending, resulting in damage.

2) Unlike nautical installation in deep sea areas, in shallow sea areas, the elongated body 14 installed on the seabed 15 has almost no residual gravitational force, so it is often curved.

Therefore, it becomes even more difficult to tow the burial machine 16 along the elongated body 14.

Method of the invention The present invention solves the above problems.

In "Figures 3 and 4", 24 is a floating body.

For this purpose, for example, a small boat 24a as shown in FIG. 5 is used.

26 is a sheep attached to its upper surface.

A buoy 24b as shown in "Fig. 6" can also be used.

28 is a roller attached to its lower surface.

A floating body 24 is floated on the sea surface near the burying machine 16, and a wire 30 is used to connect them.

Further, a wire 32 is attached to the floating body 24, and the wire 32 is towed by the winch 20 on the towing boat 10.

The wire 30 is fitted with a suitable guide device 34, such as a conventional tube.

In front of the floating body 24 (between the floating body 24 and the towing vessel 1°)
The elongated body 14 is kept afloat on the sea by a buoy 36 (conventionally, it was sunk 1:5 below the seabed).

At the floating body 240, the elongated body 14 passes over the sheave 26 of the floating body 24 (FIG. 5), or passes between the floating body 24 and the roller 28.
(FIG. 6), and then through the guide device 34 and guide it to the inlet 17 of the embedding machine 16.

After doing the above, the floating body 24 is towed by the winch 20.

Then, the burial machine 16 is indirectly towed.

The buoy 36 is removed when the elongated body 14 passes the floating body 24.

The elongated body 14 guided by the guide device 34 is successively buried by a burying machine.

Effects of the Invention By using the floating body 24, it becomes possible to lay and bury the elongated body 14 at the same time.

Therefore, even if the winch 20 for towing the burying machine 16 is far away, there is no trouble associated with towing the burying machine 16 along the laid elongated body 14 as in the prior art.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams of the prior art, FIGS. 3 and 4 are explanatory diagrams of the implementation status of the present invention, and FIGS. 5 and 6 are explanatory diagrams of the floating body 2.
FIG. 4 is an explanatory diagram of four different examples. 10...Tug ship, 14...Long body,
16... Burying machine, 20... Winch,
24...Floating object, 30 and 32...Wire.

Claims (1)

[Claims] 1. A burying machine is connected by a wire to a floating body floating on the sea nearby, a long body in front of the floating body is floating on the sea, and the burying machine is connected to the floating body. The long body is towed by a winch through the floating body, and the long body is caused to pass the floating body, and after passing the floating body, it is sunk to the seabed, and the sunken long body is buried by the burying machine. A method for burying elongated objects on the seabed in shallow trenches.