JPS61112515A - Method of laying protective pipe for submarine cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Technical Field of the Invention) The present invention relates to a method for laying protection pipes for submarine cables, and relates to a method for laying protection pipes for submarine cables. This invention relates to a method for laying a submarine cable in which both protective tubes can be simply and securely connected by covering the unnecessary gap, regardless of the length of the unnecessary gap that occurs between the protective tubes.

(Background of the invention) Submarine cables that transmit communication signals such as telegraph and telephone are
It is generally housed and protected within a protective tube. Conventionally, there are various methods for laying this type of submarine cable, and one of the widely used methods is to lay the cable on the seabed and then sequentially attach protective tubes to the cable. By the way, when laying a submarine cable by this method, as shown in FIG. It would be better to attach the cable l one by one while holding it by the universal joint 21a formed at the end, which would increase the work efficiency and shorten the construction period accordingly. The protection tube 2 (n) at the end of the protection tubes 2 laid one after another, and the protection tube 2 laid one after another from the other starting point B.
Unnecessary spacing tends to occur between the protective tubes 2(1) at the ends, and the cable 1 is exposed at this portion, which may cause damage to the cable 1. Therefore, such a gap must be eliminated by some means, but since there has been no effective means to do so, such protective tubes 2
As shown in Figure 7(a), the cables are not laid from multiple starting points A and B, but are laid in sequence from only one starting point A, as shown in Figure 7(b). Therefore, laying this type of submarine cable had the problem of requiring an extremely long construction period.

(Summary of the Invention) The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a submarine cable that enables the work of laying protection pipes for a submarine cable to be carried out advantageously from a plurality of starting points at three or more locations. The purpose of this invention is to provide a method for installing. Therefore, in order to protect cables laid on the seabed, the present invention provides protection tubes with universal joints formed at both ends of the cables, which are installed sequentially from a plurality of starting points. Universal joints formed at both ends of the protection tubes are used as protection tubes at the ends of the protection tubes laid in order from the starting point, and as protection tubes at the ends of the protection tubes laid in order from the other starting point. A joint body consisting of a pair of semi-tubular bodies made of cast iron is installed to cover the gap created between the semi-protective tubes by cutting out the universal joint section of one of the sections. is attached to the bodies of both semi-protective tubes so as to hold both semi-protective tubes, and a flange portion formed along the length of both semi-tubular bodies has a length corresponding to the length of the flange portion. A bolt nut is fastened to an elongated hole formed along the direction and an insertion hole formed in the flange portion formed along the length direction of both the semi-protective tubes. By configuring the submarine cable laying method in this way, when the protection pipe is laid from three or more starting points as shown in Figure 7 (a), the protection pipe located at the end can be This makes it possible to easily cover the unnecessary gap that tends to occur between the amphibious protective tube and the protective tube with the pair of semi-tubular bodies, regardless of its length, and to firmly connect these amphibious protective tubes to each other. By making it possible to easily and reliably cover the unnecessary gaps mentioned above, it is possible to lay protection pipes from multiple starting points, and the construction period for laying protection pipes can be greatly shortened. Furthermore, the semi-tubular body is made of heavy cast iron to ensure an anchor effect and to make it difficult to be washed away by tidal currents.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view of a joint part of a submarine cable according to the present invention, and 1 is a cable housed in a protection tube 2. FIG. The protective tube 2 consists of a pair of semi-tubular bodies 21.21, and the bolt nut 3 is inserted into the insertion hole 24 of the collar 22 formed along the length of both semi-tubular bodies 21.21. and are combined. 21a and 21b are universal joints formed at both ends of the semi-tubular body 21.21, and the joint 21b is held by the joint 21a.

These universal joints 21a and 21b are formed to freely bend the protection tube 2 according to the topography of the seabed and the like.

4 is a joint body, which is a pair of semi-tubular bodies 41 of the same size and shape.
．． It consists of 41. 42. 42 is a collar formed along the length direction on both sides of the semi-tubular body 41, and 43 is a reinforcing rib provided on the peripheral body surface of the semi-tubular body 41 in a circumferential direction. , a total of 7 are formed at equal intervals. 44
are elongated holes for inserting bolt nuts 3, two of which are formed between the ribs 43 and 43 on both end sides of the flange portion 42, for a total of eight slots, and the longitudinal direction of the bolt nut 3 is (See also Figures 2 and 3 above).

This joint body 4 is made of heavy cast iron in order to ensure sufficient strength and an anchor effect that will not be washed away by the tide. Cast iron also has the characteristic of not being rusted by seawater.

Figure 5 shows raw protection tubes 2x and 2Y, which are the protection tubes 2 divided into two.
, and each raw protection tube 2X, 2Y is the protection tube 2.
By dividing into two parts, one of the universal joint parts 21a and 21b at both ends, the universal joint part 21b,
21a are respectively cut out, and the details of how to use them will be described later. Next, a method of laying a submarine cable using the protection tube 2, raw protection tubes 2X, 2Y, and joint body 4 will be explained.

After the cable 1 is laid on the seabed, the cable 1 is laid from three or more starting points A and B as shown in Figure 7(a).
The protective tubes 2 are sequentially attached to the cable 1, but as described above, it is often unavoidable that an unnecessary gap is created between the protective tubes at the ends. In such a case, one joint part 2 is attached to both ends as shown in FIGS. 1 and 6.
The life protection tubes 2X and 2Y from which 1b and 21a have been cut are laid. Next, from above and below both semi-protective tubes 2X, 2Y, semi-tubular bodies 41, 41 are attached to the bodies of both semi-protective tubes 2X, 2Y so as to hold both semi-protective tubes 2X, 2Y. Then, insert the bolt/nut 3 into the insertion hole 24 (see FIG. 4).

The insertion holes for the bolt nuts 3 in the semi-tubular bodies 41, 41 are elongated holes 44 as described above, and therefore, regardless of the length of the above-mentioned spacing, each elongated hole 44 is inserted into each of the protective tubes 2X, 2Y.
The bolt/nut 5 can be securely inserted by aligning with the insertion hole 24 of the bolt.

(Effects of the Invention) As explained above, according to the method according to the present invention, after the cable 1 is laid on the seabed, the protective tube 2 is laid from three or more starting points. The unnecessary gap between the protective tubes is easily and reliably covered by the joint body 4 consisting of semi-tubular bodies 41 and 41 regardless of their length, and the raw protective tubes 2X and 2Y are firmly connected to each other. Therefore, since it is possible to lay the protective tube 2 from a plurality of starting points, the construction period can be shortened to a large extent. Furthermore, by making the semi-tubular bodies 41, 41 made of heavy cast iron, a sufficient anchoring effect can be ensured, and the semi-tubular bodies 41, 41 can be made difficult to flow due to tidal currents.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is an exploded perspective view of a submarine cable, Fig. 2 is a plan view of a semi-tubular body, Fig. 3 is a sectional view, and Fig. 4 is a coupled state. Fig. 5 is a perspective view of the raw protection tube, Fig. 6 is a side view during construction, Fig. 7 (
a) and (b) are explanatory diagrams of the construction method. l...Cable 2.2...Protection tube 2X, 2Y/
... Live protection tubes 21a, 21b... Universal joint portion 22... Flange portion 24... Insertion hole 3... Bolt nut 4... Joint body 41... Semi-tubular body 42
...Brim portion 44...Long hole L...Interval A, B...Starting point

Claims (1)

[Claims] In a method of laying a submarine cable, a protection tube 2 having universal joints 21a and 21b formed at both ends is sequentially attached to a cable 1 laid on the seabed from a plurality of starting points A and B. As a protection tube at the end of each of the protection tubes 2 laid in order from the starting point A, and as a protection tube at the end of each of the protection tubes 2 laid in order from the other starting point B, at both ends. Formed universal joint parts 21a, 21b
Semi-protective tubes 2X and 2Y formed by cutting out one of the universal joint portions 21b and 21a are laid, and both of these semi-protective tubes 2
In order to cover the gap L created between X and 2Y, a joint body 4 consisting of a pair of cast iron semi-tubular bodies 41, 41 is attached to the bodies of both semi-protective tubes 2X, 2Y. 2
a long hole 44 formed along the length direction, and a pot portion 2 formed along the length direction of both the semi-protective tubes 2X, 2Y.
2. A method of laying a protective tube for a submarine cable, in which bolts and nuts 3 are tightened in insertion holes 24 formed in 2.