JPH0235184B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of piping a suction pipe to be connected to the offshore end of a water pipe in a pipe yard or the like that is piped to the bottom of an ocean or a lake, for example.

Conventionally, when connecting a suction pipe to the offshore end of a pipe yard, which was installed by connecting a single pipe to the bottom of the sea or lake and then settling it,
As shown in FIG. 10, the bottom of the water near the opening at the tip of the water conduit 40 in a pipe yard or the like is excavated to form a recess a, and a foundation surface is constructed by laying chestnut b or the like in the recess a. After that, the suction pipe 42 is loaded onto a hoist boat 41 as shown in FIG. 11 and transported to a designated water area, and the suction pipe 42 is hoisted by a hoist as shown in the same figure and gradually submerged in the water, as shown in FIG. 12. As shown, with the suction pipe 42 lifted up, the water conduit pipe 4
0, backfill the recess a with soil, and install the suction pipe 40.
is buried and set in place with the suction port 42a protruding upward from the soil surface, and then a marker light mount (not shown) is similarly hoisted up using a hoist and lowered into the water, so as to correspond to the suction pipe 42. It was fixed in place.

However, according to the above method, when constructing the foundation surface, it takes a long time to excavate the water bottom considerably to form the concave part a, and then lay a large number of chestnut stones b horizontally, and it is also heavy. Large suction pipe 4
2 is difficult to connect to the water conduit pipe 40 while holding it horizontally while hoisting it in the water, and the work efficiency is extremely low.This problem is also compounded by the fact that the suction pipe 42 and the marker light stand are installed separately. The cost is high because the construction takes a long time. Moreover, in order to transport the suction pipe 42, which has a large diameter and a large weight, to a predetermined water area using the hoist ship 41, a large hoist ship 41 is required for lifting, but such a ship 41 is limited due to geographical conditions. Furthermore, there is a serious problem in that it is extremely difficult to install a large-diameter suction pipe 42 in lakes and marshes because a large hoist boat 41 cannot be used in lakes and marshes with small depths.

This invention was made in view of the above-mentioned conventional drawbacks, and the suction pipe is fixed in advance within the frame, and each opening at the upper end of the frame and the opening of the suction pipe are sealed, thereby reducing the buoyancy of the entire device. We developed a suction pipe piping method that is easy to work with, can be constructed economically by towing it floating on the water surface, and can also transport large-diameter and heavy suction pipes with a small hoist ship. The purpose is to provide

Embodiments of the present invention will be described below with reference to the drawings.

In Fig. 1 and Fig. 2, which shows a cross section taken along the line A-A' in Fig. 1, 1 indicates eight circular tubular struts, and 2 indicates a support rod. The support rods 2 are arranged at regular intervals, and the support rods 2 are horizontally hung between each two adjacent columns 1 and between each two opposing columns 1, and the reinforcing rods 3 are arranged in an inclined state between the columns 1 and 2. The frame body 4 is constructed by constructing and reinforcing the frame between the two. In this case, a lightweight pipe is used for the lower part of the support rod 2 and the reinforcing rod 3. Then, the upper end opening of each support column 1 of the frame body 4 is sealed by attaching a cover plate 5 with a structure described later.

Next, the suction pipe 6 made of a T-shaped tube is fixed to the lower part of the frame 4 with bolts 7. At this time,
The suction pipe 6 is attached with its connection port 6a protruding outside the frame 4. After or before attaching the suction pipe 6 to the frame 4, a water stop plate 8 is fixed by welding to one opening of the suction pipe 6 made of a T-shaped pipe to seal the opening. At the other opening, which is the connection port 6a, a water stop plate 9, in which a flange for removal is formed in a part, is disposed in a removable state as shown in FIG. 7, which will be described later. are joined, and the connection port 6a is sealed with the water stop plate 9.

Once the suction pipe 6 is attached to the frame 4, the frame 4
A communicating pipe 11 is attached to a position above the suction port 6b above the suction pipe 6 in a vertically movable manner by means of four guide rails 12, and then this communicating pipe 1
1 is lowered and its lower end opening is hermetically joined and fixed to the suction port 6b of the suction pipe 6, and the upper end opening of this communication pipe 11 is fitted with a lid body 15 equipped with an air valve 13 and a marker light 14. After installation, the air valve 13 is fully closed and the upper end opening is hermetically sealed with the lid 15. Then, a screen 16 is fitted onto the connecting portion between the suction pipe 6 and the communication pipe 11, and the U bolt 1 is
7 is tightened and fixed to the support rod 2, and inside this screen 16, as shown in FIGS. 4 and 9,
An annular water pipe 30 with a large number of injection nozzles 29 radially provided on the outer circumferential surface is installed in two stages, upper and lower, and a high-pressure submersible pump 3 is installed on the screen 16.
1 is installed, and the pump 31 and both water supply pipes 30 are connected through a water supply pipe 32.

The frame body 4 assembled as described above is suspended by two truck cranes and lowered into the water as shown by the dashed line in FIG. It will be hoisted up and suspended on the water surface, and in this state it will be towed by a tugboat to a designated area of water. In this case, since the upper end opening of each strut 1 and both sides of the suction pipe and the upper end opening of the communication pipe 11 are hermetically sealed as described above, a large buoyant force acts, and the suction pipe 6 Even large diameter vessels can be towed sufficiently by a small hoist ship.

Upon arrival at the designated water area, the lifting wire rope is loosened, and the assembly consisting of the suction pipe 6 and the like fixed to the frame 4 is gradually lowered, as shown in Fig. 4.
A shallow recess 19 previously excavated in the water bottom near the offshore tip of the water conduit 18 installed in advance.
A diver connects the short joint pipe 10 to the opening at the tip of the water conduit pipe 18 with a well-known joint ring 20 so that it can be expanded, contracted and bent, and each support 1 is connected so that the suction pipe 6 is in a horizontal state. Position and install. This work can be performed more reliably and quickly than in the past since the frame body 4 and the suction pipe 6 can be easily moved in any direction due to the action of large buoyancy. At this time, the upper parts of the strut 1 and the communication pipe 11 protrude above the water surface.

Next, as shown in FIG. 5, the cover plate 5 of each column 1 is removed and temporarily placed on a hoist or barge, and the protective pile 2 is inserted into the column 1 through its upper opening.
1 and drive this protective stake 21 into the water bottom to a predetermined depth with a vibrohammer, thereby fixing the frame 4 and the suction pipe 6 in a predetermined position. When the driving of all eight protective piles 21 for the eight pillars 1 is completed, the upper end of each protective pile 21 protruding from the upper end of the pillar 1 is cut to a predetermined height by level measurement. The eight lid plates 5 which have been aligned and temporarily placed are again attached to the upper end of each support column 1. To explain this installation work in detail, the eight cover plates 5 are arranged in a ring shape in accordance with the arrangement of the columns 1 on the top connecting frame 22 made of H steel and are fixed integrally, and further, as shown in FIG. As shown in FIG.
The upper end surface of the short pipe 23 is fixed by welding to airtightly seal the upper end opening of the short pipe 23, and a loose flange 24 is rotatably installed at the lower end opening edge of the short pipe 23. There is. And the top connecting frame 2
2 is lifted up, each short pipe 23 is placed on the upper end of the protection pile 21, and is joined to the upper end opening surface of the support post 1 and fixed. At that time, by rotating the loose flange 24, the bolt holes of the loose flange 24 and the mounting flange 1a on the upper edge of the support column 1 can be easily matched, and once the bolt holes are matched, , by hoisting the column 1 with a hoist or chain block, etc., and firmly joining the loose flange 24 and the mounting flange 1a of the column 1 with the gasket 24 interposed, and tightening bolts (not shown). Eight cover plates 5 are fixed to each support 1 and covered.

Next, the suction pipe 6 is connected to the water guide pipe 18. First, the air valve 13 is fully opened, and then, as shown in FIG. 7, the flange bolt 26 fixing the water stop plate 9 to the connection 6a is After loosening the water stop plate 9 until it can be removed, and also loosening the fixing bolts 28, tighten the three tap bolts 27. Here, the three tap bolts 27 are screwed into the tap holes of the short joint pipe 10, and since no screw holes are bored in the flange of the suction pipe 6 facing the three tap bolts 27, the tap bolts 27 described above are By tightening, a gap is formed between the opposing end surfaces of the short joint pipe 10 and the suction pipe 6. Therefore, remove the water stop plate 9 upward as shown by the arrow in FIG. and fixing bolts 28 are fully tightened, and the suction pipe 6 is connected to the joint short pipe 10.
It is communicated and fixed to the water conduit pipe 18 via.

Next, as shown in FIG. 8, soil in the vicinity of the suction pipe 6 is backfilled into the recess 19, and the suction pipe 6 is backfilled to the point where its suction port 6b is exposed above the water bottom, and then the suction pipe 6 is covered with stone. After that, the suction port 6 of the suction pipe 6
When the flange bolts (not shown) fixing b and the communication pipe 11 are removed and the communication pipe 11 is moved upward along the guide rail 12, water flows onto the screen 1.
After being filtered through the water pipe 6, the water flows from the suction port 6b through the suction pipe 6 into the water conduit pipe 18, and the installation work is completed.

Note that if used for a long period of time, sludge and the like will adhere to or settle on the inner surfaces of the water conduit 18 and suction pipe 6, reducing the water intake efficiency.
is moved downward to bring it into close communication with the suction port 6b by its own weight, and the cover body 15 is removed and the submersible sand pump is installed inside the communication pipe 11.
If a water injection pipe is provided at the land side end of the water pipe 18 and a nozzle is inserted and driven using a water injection pump or a high-pressure jet pump, the flow rate of the water flowing in the water conduit pipe 18 in the opposite direction to the water intake direction will increase the water flow rate. As a result, the sludge adhering to the inner surface of the tube is washed away and removed. Alternatively, the sludge may be sprayed back toward the water outlet using a high-pressure washing vehicle installed on the barge and a reverse spray nozzle, and then pulled out using a powerful absorption vehicle or submersible sand pump and discharged into the silt protector. The suction pipe installed using the conventional method has its suction port immersed in water, making it impossible to clean the inside of the pipe as described above. However, the suction pipe 6 installed using the method of the above embodiment Since the suction port 6b is watertightly partitioned from seawater or lake water by the communication pipe 11 and can be communicated with the water surface, cleaning can be easily performed using the flow velocity without water pressure resistance. Further, the screen 16 can be easily cleaned by stopping the water intake pump, and then driving the high-pressure submersible pump 31 to spray water in the opposite direction from the spray nozzle 29 onto the screen 16 surface. Ru.

As described above, according to the method of piping a suction pipe in a sea-lake water conduit pipe according to the present invention, by sealing each opening of the suction pipe and the frame body that fixes it, buoyancy is used to connect the suction pipe to the water surface. Since it is towed in a floating state, it is possible to install large diameter and heavy suction pipes using a small hoist ship, and the suction pipes are fixed to the frame in advance on land and the frame is lowered to the bottom of the water. Since the foundation surface is constructed by driving protective piles using the pillars as guides, work efficiency is extremely high compared to conventional construction work for foundation surfaces, and the construction period is significantly shortened. This has the advantage of significantly reducing costs.

[Brief explanation of drawings]

1 to 8 show the steps of an embodiment of the method for piping a suction pipe in a sea/lake bottom water conduit according to the present invention; FIG. 1 is a front view of an assembly in which a suction pipe is attached to a frame; Figure 2 is a sectional view taken along line A-A' in Figure 1.
Figure 3 is a front view of the assembly shown in Figure 1 being towed, Figure 4 is a front view of the assembly submerged in a designated water area and temporarily connected to a water pipe, and Figure 5 is a front view of the assembly shown in Figure 1 being towed. Figure 6 is a front view showing the installation state, Figure 6 is a front view with the upper end opening of the column covered with a cover plate, Figure 7 is a partial right side view showing the relationship between the suction pipe and the water stop plate, Fig. 8 is a front view of the completed installation, Fig. 9 is a partial plan view showing the screen and its dust removal mechanism, Figs. 10 to 12 show the steps of the conventional suction pipe piping method, and Fig. 10 11 is a front view of the foundation constructed on the water bottom where piping is to be installed, FIG. 11 is a front view of the suction pipe being towed, and FIG. 12 is a front view of the suction pipe being joined to the water conduit pipe. 1... Support column, 2... Support rod, 4... Frame, 5...
...Lid plate, 6...Suction pipe, 6a...Connection port, 6b...
... Suction port, 9 ... Water stop plate, 10 ... Joint short pipe, 1
3...Air valve, 15...Lid, 18...Water pipe,
21...protective stake.

Claims (1)

[Claims] 1. A frame is constructed by arranging a plurality of tubular struts in a ring in an upright state, and constructing a support rod between each two of the struts, and fixing a suction pipe to the lower part of the frame; The upper end opening of each of the above-mentioned pillars is sealed by attaching a cover plate, and the suction port of the above-mentioned suction pipe is closed.
A connection port whose upper end opening is covered by a lid body provided with an air valve and which is movable up and down is airtightly joined and sealed, and which projects horizontally from the frame body of the suction pipe. A water stop plate is interposed in a removable state to connect the connecting leg short pipe, and the frame body incorporating the suction pipe as described above is suspended in a floating state on the water surface and towed,
The frame body is lowered to the bottom of the water at a predetermined location, the short joint pipe is connected to the tip of the water conduit pipe, and each support is erected vertically to the bottom of the water to hold the suction pipe horizontally. Temporarily remove the cover plate, insert protective stakes into each support and drive them to the bottom of the water, cut these protection piles to a predetermined height, and then attach the cover plate to each support,
After the air valve is opened and the water stop plate is removed to fill the suction pipe with water, the suction pipe and the joint short pipe are tightly fixed, and the communication pipe is moved upward to separate it from the suction pipe. A method for piping a suction pipe in a sea-lake bottom water conduit pipe, which is characterized by: