JPS5914676B2 - How to join underwater pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a joint structure for underwater pipes.

Conventionally, it has been used as a joint structure for underwater pipes such as water intake pipes, which are installed with an intake port opened at the bottom of the water near the shore in order to take water for power generation or cooling from a river, sea, or lake. There was something like the following.

That is, 1) normal flange joint, 2) loose type flange joint, and 3) loose type flange joint with sheath tube.However, the above joint structures 1 to 3 had the following problems.

In other words, in the case of the joint structure described in 1 above, it takes a lot of time to center the pipes together because the work is done underwater, and the bolts are tightened by divers, which tends to result in uneven tightening, especially when tightening the bolts at the bottom of the installed pipes. There was a risk that it would be incomplete.

The above 2 joint structure has one or both IE flanges of the loose type, and the centering during joining is the 1 above.
Although this method is easier than in the case of 1, it is difficult to tighten the bolts at the bottom of the installed pipe because they tend to be tightened unevenly.

7. The joint structure in 3 above has a sheath tube and an insertion tube attached to the flexible flange in 2 above, and surface matching and centering are easier compared to the joint structures in 1 and 2 above. As in the case of the above-mentioned joint structure, it was difficult to tighten the bolts at the bottom of the installed pipe because the bolts tended to be tightened unevenly.

As mentioned above, what is common to joint structures 1 to 3 is that the bolting at the bottom of the laying pipe tends to be incomplete. Conventionally, when tightening the bolts at the bottom of the laying pipe, They dug up the trench and hoisted the pipe to a certain height above the water bottom.

For this reason, there were problems such as a lot of time and expense required for joining.

This invention was made in order to solve the problems of the conventional underwater pipe connection structure as described above, and has a tapered receiving fitting in the lower half and a bolt in the upper half. A fixing flange having a hole is fixed to one end of the laying pipe, and a stub end whose lower half can be tapered and fitted into the receiving fitting is connected to the other end of the laying pipe. A loose flange that is fixed to the pipe end and has bolt holes provided on the entire circumference at the same intervals as the bolt holes of the fixed flange is loosely fitted to the other laid pipe end, and the upper part of the fixed flange and this A pulling wire is inserted into a wire guide protruding from the upper part of the corresponding loose flange, and the pulling wire pulls the other laying pipe end to one laying pipe end, and the lower half of the stub end is pulled to the lower half of the stub end. is fitted into the receiving fitting, and then the upper halves of both laid pipe ends are bolted together via the loose flange to join the two pipe ends.

This invention will be explained by way of examples and with drawings.

FIG. 1 is a sectional view of a joining structure according to an embodiment of the present invention.

Figure 2 is a sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view of Figure 1.
It is a sectional view taken along the line BB in the figure.

As shown in the figure, in this joint structure for underwater pipes, a fixed flange 2 is fixed to the end of one pipe 1.

A receiving metal fitting 4 is fixed to the lower half of the fixed flange 2, and bolt holes 5 are provided at predetermined intervals in the upper half of the fixed flange 2.

A tapered surface 3 is formed on the inner circumferential side of the receiving fitting 4, and a drain hole 6 is provided through the bottom of the receiving fitting 4, and is fixed to the lower half of the stub end, which will be described later. Water inside the receiving metal fitting 4 can be drained when the close contact fitting is inserted into the receiving metal fitting 4.

Furthermore, a protrusion 15 is provided on the bottom of the receiving fitting 4 to fit into a groove formed in a fitting fitting of the other installed pipe, which will be described later, to facilitate circumferential positioning of the other pipe end. However, the positioning protrusion 15 is not necessarily necessary.

On the other hand, a stub end 8 is fixed to the tube end of the other laying pipe 7 that is joined to the tube end of the one laying pipe 1.

In the lower half of the stub end 8. Said one laying pipe 1
A close fitting fitting 9 that can be inserted into the receiving fitting 4 from above the receiving fitting 4.
is fixed.

A concave groove 16 is formed in the bottom of the close fitting 9 to fit with the protrusion 15 of the receiving metal 4, and the side peripheral surface of the close fitting 9 has the same taper angle as the tapered surface 3 of the receiving portion 4. A tapered surface 10 is formed.

Therefore, if the cap attachment fitting 9 is dropped into the receiving fitting 4, the fitting fitting 9 and the receiving fitting 4 will be connected to the stub end 8.
is fitted tightly to the two surfaces of the fixed flange, and at the same time, the centering of both pipe ends can be performed.

The width (height) of the upper half of the stub end 8 is narrower (lower) than the width (height) of the fixing flange 2 up to the bolt hole 5 position.

This is, of course, to prevent any hindrance to the insertion of a joining bolt, which will be described later.

Further, a gasket 12 is provided on the outer peripheral surface of the stub end 8.
is fixed to the fixing flange 2 to improve the adhesion with the fixed flange 2.

Furthermore, a loose flange 13 is provided at the tube end of the other installation pipe 7 in a loosely fitted state with respect to the other installation pipe I.

Bolt holes 14 are formed in the loose flange 13 at the same intervals as the bolt holes 5 provided in the fixed flange 2.

(Since the joining structure of this embodiment is configured as described above, in order to join one laying pipe 1 to the other laying pipe 7,
First, the contact fitting 9 of the other newly installed pipe I is inserted into the receiving metal fitting 4 of one of the existing pipes 1 from above the receiving metal fitting 4.

As a result, the fitting fitting 9 is fitted tightly into the receiving fitting 4, and as a result, the stub end 8 comes into close contact with the surface of the fixed flange 2, and the centering of both pipe ends is performed.

In addition, by fitting the protrusion 15 of the receiving metal fitting 4 into the groove 16 of the close fitting metal fitting 9, the other installed pipe I can be positioned in the circumferential direction.

At this time, the loose 7 flange 13 is also inserted into the receiving part 4 at the same time.

Next, the bolt hole 5 provided in the upper half of the fixed flange 2 of one laying pipe 1 and the corresponding loose flange 1
A joining bolt 17 is inserted into the bolt hole 14 of No. 3, and its both ends are fastened with nuts 18.

; Next, by fixing wire guides 20 having wire insertion holes 19 to the upper part of the fixed flange 2 of one laying pipe 1 and the corresponding upper part of the corresponding loose flange 13, it is possible to connect the other laying pipe I. The pulling operation to one of the laying pipes 1 can be easily performed.

That is, as shown in FIG.
As shown in FIG. 3, a pulling piece 21 is fixed to the upper part of the pipe end of the existing pipe 1, and a pulling wire 23 from the pulling work vessel 22 is attached to the pulling piece 21 of the existing pipe 1.
Pull piece 2 of the other laying pipe 7 through the wire guide 20 and the wire guide 20 of the newly installed other laying pipe T.
Fixed to 1.

Since the other laid pipe 7 is lifted to a predetermined position in the water by the ship 22 and the crane ship 24, when the pulling wire 23 is operated and pulled, the end of the other laid pipe I is pulled. Guided by the wire 23, the one installation pipe 1 is accurately drawn to the position where it is dropped into the receiving fitting 4.

By using the pulling wire 23 in this manner, the joining work can be carried out reliably even when the current is relatively fast.

As explained above, according to the present invention, it is possible to firmly and accurately join underwater pipes, and it is no longer necessary to tighten bolts at the joints at the bottom of the pipes, which was extremely difficult to tighten. Since only half of the parts need to be bolted, the time required for joining is significantly shortened, which has the advantage of reducing costs.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a joint structure of an underwater pipe according to the present invention; Fig. 2 is a cross-sectional view taken along the line A-A in Fig. 1; and Fig. 3 is a cross-sectional view taken along the line B-B in Fig. 1. The sectional view and FIG. 4 are explanatory diagrams showing a joining mode of laying pipes having the same joining structure. In the drawing, 1... one laying pipe, 2...
...Fixed flange, 3...Tapered surface, 4.
...Bracket, 5...Bolt hole, 6...
...Drain hole, I...Other laying pipe, 8...
... Stub end, 9 ... Close contact all holes 10.
...Taber surface, 11 ...Bolt hole, 12
... Gasket, 13 ... Loose flange, 14 ... Bolt hole, 15 ... Protrusion, 16 ... Concave groove, 17 ... ····bolt,
18... Nut, 19... Wire insertion hole, 20... Wire guide, 21...
... Pulling piece, 22... Pulling work vessel,
23... Pulling wire, 24... Crane ship.

Claims (1)

[Claims] 1. A fixed flange with a tapered receiving fitting in the lower half and a bolt hole in the upper half is fixed to one end of the laying pipe,
A stub end whose lower half can be tapered and fitted into the receiving fitting is fixed to the other laying pipe end that is joined to the one laying pipe end, and bolt holes are provided around the entire circumference of the fixed flange. A wire guide in which a loose flange provided at the same interval as the bolt hole is loosely fitted into the other end of the laying pipe, and protrudes from an upper part of the fixed flange and a corresponding upper part of the loose flange. A pulling wire is inserted into the pipe, the other laying pipe end is pulled to one laying pipe end by the pulling wire, and after the lower half of the stub end is fitted into the receiving metal fitting, the lower half of the stub end is inserted through the loose flange. A method for joining underwater pipes, characterized in that the two pipe ends are joined by bolting the upper halves of both pipe ends.