JP6861435B2 - Water stop device - Google Patents

Description

The present invention relates to a water blocking device that is inserted into a tube and used to block the middle of the tube.

For example, Patent Document 1 describes a balloon for plumbing work. This balloon has a balloon body made of a rubber material attached to the outer circumference of a tubular core metal, and pressure air is sent into the balloon body from an air supply pipe to inflate the balloon body, thereby isolating the inside of the pipe into two. It has become like.

Further, Patent Document 2 describes a water stop device for stopping the flow of water in a water channel pipe. In this water stop tool, a drain pipe is inserted in the center of the elastic bag-shaped body, and the elastic bag-shaped body is filled with air from a supply / discharge valve and expanded to expand the circular shape of the outer periphery of the elastic bag-shaped body. The arc-shaped outer surface is elastically contacted with the inner peripheral surface of the water channel pipe to close the water channel pipe.

Further, Patent Document 3 describes a heat-resistant packer for gas construction. This packer closes the middle of the gas pipe by filling the inside of the packer body with cooling water or compressed air supplied from the inside of the guide member inserted into the packer body.

Jikkai Sho 54-179523 Japanese Unexamined Patent Publication No. 7-173866 Japanese Unexamined Patent Publication No. 2001-124283

In Patent Documents 1 to 3, since the balloon body, the elastic bag-like body, and the packer body are only formed of an elastic body such as rubber, there is a concern that the pressure resistance may be insufficient depending on the usage environment. Will be done.

Further, in Patent Documents 1 to 3, when the balloon body, the elastic bag-like body, and the packer body are inflated, both ends thereof are arranged at the centers thereof (the tubular core metal, the drain pipe, and the members). The radial dimension when not inflated is set larger than the relationship that the guide member) is regulated so as not to inflate in the axial direction.

Therefore, in the radial direction, the balloon body, the elastic bag-like body, and the packer body can be inserted into the pipe body (the pipe, the water channel pipe, and the gas pipe) to be used when not inflated. It is necessary to fold it compactly inward, and it is necessary to devise a folding form so that it can be easily expanded at that time.

In view of such circumstances, the present invention makes it easy to insert into the pipe body when it is not inflated and has excellent pressure resistance in a water stop device which is inserted into the pipe body and used to close the middle of the pipe body. The purpose is to make the balloon inflatable smoothly.

The present invention is a water blocking device that is inserted into a tube and used to close the middle of the tube, and has a tubular shape with an intermediate portion in the central axis direction having a larger diameter than one end portion and the other end portion. An elastically stretchable balloon, a core rod inserted in the entire central axis direction of the balloon and having an air supply path inside for supplying pressurized gas into the balloon, and outside one end portion of the balloon. A first fixture for pressing one end portion of the outer peripheral surface of the core rod to one end side in the central axis direction and immovably fixing the core rod in the direction of the central axis by being fitted on the diameter side, and the core rod. A slide sleeve that is slidably and displaceably fitted to the other end side of the outer peripheral surface in the central axis direction, a seal ring that makes the fitting surface between the slide sleeve and the core rod airtight, and the balloon. A second fixture for pressing the other end portion against the outer peripheral surface of the slide sleeve and immovably fixing the other end portion in the central axis direction by being fitted to the outer diameter side of the other end portion of the slide sleeve is provided. The outer diameter of the first and second fixtures is set to be smaller than the inner diameter of the entrance / exit of the water stop device with respect to the pipe body to be stopped, and when the intermediate portion in the central axis direction of the balloon is not inflated. The outer diameter of the first and second fixtures is set to be equal to or less than the outer diameter of the first and second fixtures, and the inside of the balloon extends along the central axis direction and is located at a plurality of locations in the circumferential direction. reinforcement wires are embedded, it is characterized in that.

In this configuration, the water blocking device can be relatively easily inserted into the tube body to be water-stopped without excessively increasing the radial dimension of the balloon before expansion.

Moreover, in the above configuration, since the balloon is reinforced with a reinforcing wire, it is possible to secure pressure resistance while reducing the wall thickness of the balloon. Therefore, the water stop device according to the present invention can be suitably used when temporarily closing a pipe body (such as a drain pipe of a tank for storing a liquid such as water) to be stopped.

Further, in the water stop device according to the present invention, in the process of supplying the pressurized gas into the balloon, the other end portion fixed to the slide sleeve is fixed to the core rod by the first fixture. The sliding displacement toward one end portion causes the intermediate portion of the balloon to smoothly bulge outward in the radial direction.

As a result, stress is less likely to be concentrated on the one end portion and the other end portion, and the amount of extension of the intermediate portion is reduced, so that the durability of the balloon is improved.

Further, the water stop device is inserted by suspending and inserting the second fixture in an upward opening of the pipe body to be stopped, with the second fixture facing down and the first fixture facing up. It is preferable that the first fixture is attached with a stopper member that is hooked from above on the peripheral edge of the upward opening of the pipe body to be water-stopped.

With this configuration, the water stop device according to the present invention can be easily used for the pipe body to be stopped.

Further, in the water blocking device, the balloon has a two-layer structure in which the balloons are laminated in the radial direction, the inner diameter side layer is made of a material having excellent gas impermeable property, and the outer diameter side layer is weather resistant. It is preferable that it is an excellent material.

As described above, according to the balloon having the two-layer structure of the present invention, the permeation of the pressurized gas can be prevented, and the inner peripheral surface is pressed against the inner peripheral surface of the tubular body over time. It becomes possible to prevent the contamination.

Further, in the water blocking device, it is preferable that the wall thickness of the intermediate portion of the balloon is set thinner than that of other regions.

In this configuration, even if the pressure of the pressurized gas supplied into the balloon is lowered as much as possible, the intermediate portion of the balloon is likely to expand. This improves the operability of the balloon when it is inflated.

Further, in the water blocking device, it is preferable that the wall thickness of one end portion and the other end portion of the balloon is gradually increased toward the end edge, respectively.

In this configuration, the fixing strength to the core rod is improved when the balloon is inflated. This improves the pressure resistance of the balloon when it is inflated.

The water blocking device according to the present invention has excellent pressure resistance and can easily inflate the balloon after being easily inserted into the pipe body to be stopped when not inflated.

It is a side view which made the cross section of one half of one Embodiment of the water stop device which concerns on this invention. It is an end view which shows one end side of FIG. It is the figure which looked at the cross section (3)-(3) of FIG. 1 from the direction of an arrow. It is a perspective view which shows a part of the internal structure of the balloon of FIG. It is sectional drawing which shows the use target of the water stop device which concerns on this invention. FIG. 5 is a cross-sectional view showing a state in which a water stop device is inserted into the first pipe in FIG. It is a top view of the stopper member of the water stop device of FIG. FIG. 6 is a cross-sectional view showing a state in which the balloon of the water blocking device is inflated in FIG. It is the figure which looked at the cross section (9)-(9) of FIG. 8 from the direction of an arrow. FIG. 5 is a cross-sectional view showing a state in which a water stop device is inserted into the second pipe in FIG. FIG. 10 is a cross-sectional view showing a state in which the balloon of the water blocking device is inflated in FIG. It is a figure corresponding to FIG. 8 in another embodiment of the water stop device which concerns on this invention. It is a figure corresponding to FIG. 8 in another embodiment of the water stop device which concerns on this invention. It is a figure corresponding to FIG. 8 in another embodiment of the water stop device which concerns on this invention.

Hereinafter, the best embodiment for carrying out the present invention will be described in detail with reference to the accompanying drawings.

1 to 11 show an embodiment of the present invention. In the figure, 1 indicates the entire water stop device.

The water stop device 1 includes a core rod 2, a balloon 3, a first fixture 4, a second fixture 5, a slide sleeve 6, and the like.

The core rod 2 is a solid round bar member. Inside the core rod 2, an air supply passage 2a for supplying a pressurized gas (for example, air) into the balloon 3 is provided. The air supply passage 2a is provided so as to open outward in the radial direction at a predetermined position in the intermediate portion in the axial direction from one end side in the axial direction of the core rod 2.

The other end side of the core rod 2 in the axial direction is formed to have a smaller diameter than the other regions. Reference numeral 2b is attached to this small diameter portion. Further, at a predetermined position on one end side in the axial direction of the core rod 2, a ring-shaped convex portion 2c that protrudes outward in the radial direction and is continuous in the circumferential direction is provided. The ring-shaped convex portion 2c is provided to increase the fixing strength when the one end portion 3a of the balloon 3 described below is fixed by the first fixture 4.

Such a core rod 2 is formed of, for example, an appropriate metal material or a synthetic resin having a predetermined strength.

The balloon 3 is made of an elastic material that can be elastically expanded and contracted, has a cylindrical shape before expansion, and has a middle portion 3c in the central axis direction having a diameter larger than that of one end portion 3a and the other end portion 3b. There is.

The balloon 3 is made of, for example, a single elastic material. Examples of this elastic material include chloroprene rubber (CR), styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR), ethylene propylene co-rubber (EPDM), silicon rubber (SI), and the like.

Inside the balloon 3, the reinforcing member 8 is embedded in multiple places in the circle circumferentially together when extending along a central axis direction.

Examples of the reinforcing wire 8 include appropriate metal materials or chemical fibers (polyamide-based, polyester-based) and the like. The reinforcing wire 8 is preferably formed by being inserted into a mold when the balloon 3 is formed. At the time of this molding, in order to ensure relative positioning and prevention of loosening of a large number of reinforcing wires 8, although not shown, the large number of reinforcing wires 8 are bundled with horizontal lines along the circumferential direction. Is preferable.

The first fixture 4 is fitted to the outer diameter side of one end portion 3a of the balloon 3 so that the one end portion 3a is pressed against one end side in the central axis direction on the outer peripheral surface of the core rod 2 in the central axis direction. Fix it immovably.

The second fixture 5 is fitted to the outer diameter side of the other end portion 3b of the balloon 3 so that the other end portion 3b is pressed against the outer peripheral surface of the slide sleeve 6 and fixed immovably in the central axis direction thereof. ..

The slide sleeve 6 is fitted (for example, a clearance fit) to the small diameter portion 2b on the outer peripheral surface of the core rod 2 on the other end side in the central axis direction so as to be slidable and displaceable. The other end side of the balloon 3 is fitted and fixed to the outer diameter side of the slide sleeve 6 by using the second fixture 5 as described above.

The wall thickness of the slide sleeve 6 is set to be the same as or substantially the same as the difference in the outer diameter dimension between the small diameter portion 2b and the other portion of the core rod 2. As a result, when the slide sleeve 6 is fitted to the small diameter portion 2b of the core rod 2, the outer peripheral surface of the slide sleeve 6 becomes flush with or substantially flush with the outer peripheral surface of the portion other than the small diameter portion 2b of the core rod 2.

Further, on one end side (inner end side) of the slide sleeve 6 in the axial direction, a ring-shaped convex portion 6a projecting outward in the radial direction is provided.

The ring-shaped convex portion 6a is provided to regulate the maximum slide position of the slide sleeve 6 when the balloon 3 is inflated, and to position and prevent the balloon 3 from coming off. That is, in the process of sliding the slide sleeve 6, when the ring-shaped convex portion 6a abuts on the step wall surface between the small diameter portion 2b and the other region on the core rod 2, the slide of the slide sleeve 6 is forcibly stopped. Will be done. Further, the fixing strength can be increased by positioning and preventing the other end portion 3a of the balloon 3 from coming off by the ring-shaped convex portion 6a and the second fixture 5.

Further, on the inner peripheral surface of the slide sleeve 6, a peripheral groove 6b is formed on one end side (inner end side) in the axial direction. A seal ring 7 such as an O-ring is mounted in the peripheral groove 6b so as to protrude inward in the radial direction. The seal ring 7 makes the fitting surface between the slide sleeve 6 and the core rod 2 airtight.

The slide sleeve 6 is formed of, for example, a material that reduces frictional resistance, or the slide sleeve 6 is formed of an appropriate metal material or a synthetic resin having a predetermined strength, and a material that reduces frictional resistance is formed on the inner peripheral surface thereof. It is preferable to coat it.

Then, when the balloon 3 is inflated, as the balloon 3 is inflated, the other end portion 3b of the balloon 3 is smoothly slid and displaced with respect to the core rod 2 toward the one end portion 3a together with the slide sleeve 6. Therefore, the balloon 3 can be easily inflated.

By the way, the first and second fixtures 4 and 5 have a two-divided structure, and one of the semicircular members is provided with insertion holes 4b and 5b for connecting bolts 4a and 5a, and the other semicircular member. Is provided with screw holes 4c and 5c into which the connecting bolts 4a and 5a are screwed.

That is, the first and second fixtures 4 and 5 are fastened to one end portion 3a and the other end portion 3b of the balloon 3 from the outer side in the radial direction to the inward side in the radial direction, so that the one end portion 3a of the balloon 3 is tightened to the core rod 2 Also, it is used to fix the other end 3b of the balloon 3 to the slide sleeve 6.

Further, the outer diameters of the first and second fixtures 4 and 5 are upward openings (connection ends to the tank 20) of the pipe body to be water-stopped (for example, the first pipe 21 and the second pipe 22 in FIG. 5). The outer diameter of the middle portion 3c in the central axis direction of the balloon 3 when not inflated is set to be smaller than the inner diameter of the first and second fixtures 4 and 5 and equal to or less than the outer diameter of the first and second fixtures 4 and 5. .. The upward opening of the first pipe 21 and the second pipe 22) corresponds to the entrance / exit of the water stop device 1.

Further, in the balloon 3, the outer diameter of the intermediate portion 3c in the central axis direction at the time of expansion is made larger than the inner diameter of the pipe body (for example, the first pipe 21 and the second pipe 22 in FIG. 5) to be stopped. It is set.

Next, a usage mode of the water stop device 1 having the above configuration will be described.

Examples of the target of use of the water stop device 1 include a tank 20 of an appropriate plant as shown in FIG.

Two pipe bodies (first pipe 21, second pipe 22) are connected to the bottom of the tank 20. Although not shown, appropriate equipment to which the liquid in the tank 20 is supplied is connected to the tip side of the first and second pipes 21 and 22. A valve 23 for controlling the opening degree of the internal passage is provided in the middle of the first pipe 21.

Here, when replacing or repairing the valve 23 of the first pipe 21 without draining the liquid in the tank 20, or when replacing or repairing the second pipe 22 without draining the liquid in the tank 20, water is stopped. Device 1 is used.

Specifically, for example, as shown in FIG. 1 or FIG. 10, the water stop device 1 is inserted through the upward openings (connection ends with respect to the tank 20) of the first and second pipes 21 and 22.

At this time, the stopper member 9 is attached to one end side of the core rod 2 of the water stop device 1 in the axial direction via the wire 10 and the attachment 11.

As shown in FIG. 7, the stopper member 9 is formed in a strip shape, and the total length dimension thereof is set to be larger than the inner diameter dimension of the upward openings of the first and second pipes 21 and 22. In order to prevent misalignment when the stopper member 9 is hooked on the upward openings of the first and second pipes 21 and 22, projecting pieces 9a and 9b are provided on one side of the stopper member 9 at both ends in the longitudinal direction. There is. The stopper member 9 can be attached to the core rod 2 of the water stop device 1 in advance.

That is, when inserting the water stop device 1, the second fixture 5 is inserted downward and the first fixture 4 is inserted upward, and the stopper member 9 is inserted into the first and second pipes 21 and 22. If the water stop device 1 is hooked on the upward opening, the water stop device 1 can be held in a suspended state.

By the way, the upward opening of the first pipe 21 has a straight pipe shape having a uniform inner diameter dimension, but the upward opening of the second pipe 22 has a tapered shape such that the diameter gradually increases as the inner diameter dimension moves away from the edge. ing.

It is preferable that the outer diameter of the water stop device 1 to be inserted into the second pipe 22 is set to be slightly smaller than the inner diameter of the edge of the upward opening of the second pipe 22. Further, for example, in the process of inserting the water stop device 1 into the first and second pipes 21 and 22, the diameter of the balloon 3 may be reduced due to the water pressure in the tank and the balloon 3 may be brought into close contact with the outer peripheral surface of the core rod 2. It is preferable to set the outer diameter of the reduced diameter portion to be slightly smaller than the inner diameter of the upward openings of the first and second pipes 21 and 22.

Then, after inserting the water stop device 1 into the upward openings of the first and second pipes 21 and 22 as described above, the pressurized gas (air) is supplied to the balloon 3 of the water stop device 1 from the air supply passage 2a. As a result, as shown in FIGS. 8, 9 and 11, the balloon 3 is inflated so that the outer peripheral surface of the balloon 3 is pressed against the inner peripheral surfaces of the first and second pipes 21 and 22.

As a result, the upward openings of the first and second pipes 21 and 22 are closed, and the liquid in the tank 20 is prevented from leaking to the outside. Therefore, maintenance and inspection work including replacement or repair of the valve 23 and maintenance and inspection work including replacement or repair of the second pipe 22 can be easily performed.

As described above, according to the embodiment to which the present invention is applied, the water stop device 1 is a pipe body (first pipe 21) to be stopped without excessively increasing the radial dimension of the balloon 3 before expansion. , It becomes possible to insert it into the second pipe 22) relatively easily.

Further, since the balloon 3 is reinforced with the reinforcing wire rod 8, it is possible to secure the pressure resistance while reducing the wall thickness of the balloon 3. Therefore, the water stop device 1 according to the present invention can be suitably used when temporarily closing the pipe body (first pipe 21, second pipe 22) to be stopped.

Further, in the water stop device 1 according to the present invention, in the process of supplying the pressurized gas into the balloon 3, the other end portion 3b of the balloon 3 fixed to the slide sleeve 6 is attached to the core rod 2 by the first fixture 4. The intermediate portion 3c of the balloon 3 is smoothly bulged outward in the radial direction due to the sliding displacement toward the one end portion 3a of the balloon 3 fixed to the balloon 3.

As a result, stress is less likely to be concentrated on one end portion 3a and the other end portion 3b of the balloon 3, and the amount of extension of the intermediate portion 3c of the balloon 3 is reduced, so that the durability of the balloon 3 is improved.

The present invention is not limited to the above embodiment, and can be appropriately modified within the scope of claims and within the scope equivalent to the scope.

(1) In the above embodiment, an example in which the wall thickness of the balloon 3 is set uniformly over the entire central axis direction is given, but the present invention is not limited to this.

For example, although not shown, the wall thickness of the intermediate portion 3c of the balloon 3 can be set thinner than that of other regions.

In this case, even if the pressure of the pressurized gas supplied into the balloon 3 is lowered as much as possible, the intermediate portion 3c of the balloon 3 is likely to expand. This improves the operability of the balloon 3 when it is inflated.

Further, for example, although not shown, the wall thickness of one end portion 3a and the other end portion 3b of the balloon 3 can be gradually increased toward the end edge, respectively.

In this case, the fixing strength to the core rod 2 is improved when the balloon 3 is inflated. This improves the pressure resistance of the balloon 3 when it is inflated.

(2) In the above embodiment, an example in which the balloon 3 has a one-layer structure is given, but the present invention is not limited to this, and for example, the balloon 3 can have a two-layer structure.

Specifically, when the balloon 3 has a two-layer structure, the inner diameter side layer thereof is made of a material having excellent gas impermeable properties (for example, general-purpose rubbers such as CR, SBR, NBR, etc.), and the outer diameter side is used. It is preferable that the layer is made of a material having excellent weather resistance (for example, EPDM, SI, etc.).

When the balloon 3 has a two-layer structure in this way, the layer on the inner diameter side of the balloon 3 prevents the pressurized gas supplied into the balloon 3 from permeating to the outside, and the outer diameter of the balloon 3 By pressing the side layer against the inner peripheral surfaces of the first and second pipes 21 and 22, the inner peripheral surface is prevented from being contaminated over time. As a result, the usability is improved, for example, the usage environment of the balloon 3 is not restricted.

(3) In the above embodiment, it is possible to bury two or more reinforcing wires 8 in the balloon 3 in the radial direction at a distance of two or more.

In this case, the rigidity of one end portion 3a and the other end portion 3b of the balloon 3 is further improved, which can contribute to further improvement of the pressure resistance of the balloon 3.

(4) In the above embodiment, an example in which the shape of the balloon 3 before expansion is cylindrical is given, but the present invention is not limited to this, and for example, although not shown, the balloon 3 The shape before expansion can be a square cylinder, an elliptical cylinder, or the like.

(5) In the above embodiment, the stopper member 9 is attached to one end side of the core rod 2 of the water stop device 1 in the axial direction via the wire 10 and the attachment 11, so that the first fixture 4 is turned up and the first fixture 4 is turned up. 2 An example is given in which the fixture 5 is inserted into the first and second pipes 21 and 22 in a posture of facing down, but the present invention is not limited to this.

For example, although not shown, the stopper member 9 is attached to the other end side of the core rod 2 of the water stop device 1 in the axial direction via the wire 10 and the attachment 11, so that the second fixture 5 is turned up and the second fixture 5 is placed on the top. 1 It is also possible to insert the fixture 4 into the first and second pipes 21 and 22 in a posture of facing down.

(6) In the above embodiment, an example in which the core rod 2 is solid is given, but the present invention is not limited to this, and is hollow in the center of the core rod 2, for example, as shown in FIG. It is also possible to form a part.

(7) In the above embodiment, an example in which the outer shape of the core rod 2 is circular is given, but the present invention is not limited to this, and for example, although not shown, the outer shape of the core rod 2 is many. It can also be rectangular or elliptical.

(8) In the above embodiment, an example in which the outer diameter of the region from one end side in the axial direction of the core rod 2 to the intermediate portion in the axial direction is constant is given, but the present invention is not limited to this. ..

For example, as shown in FIG. 13, the outer diameter dimension of the axially intermediate portion of the core rod 2 can be set smaller than the outer diameter dimension of the one end side in the axial direction and the other end side in the axial direction.

(9) In the above embodiment, an example in which the core rod 2 has a one-piece structure is given, but the present invention is not limited to this.

Further, for example, as shown in FIG. 14, the core rod 2 is combined with an arbitrary number (for example, three) members (first short round bar member 2A, second short round bar member 2B, connecting shaft 2C, fixing nut 2D). It is possible to configure it.

A ring-shaped convex portion 2c is provided in the middle of the first short round bar member 2A in the axial direction in order to increase the fixing strength of the balloon 3 by the first fixture 4. At the inner end of the second short round bar member 2B, in order to regulate the slide stroke of the slide sleeve 6 when the balloon 3 is inflated,
Further, a ring-shaped convex portion 2E is provided in order to increase the fixing strength of the balloon 3 by the second fixture 5. The outer diameter dimension of the second short round bar member 2B is appropriately set smaller than the outer diameter dimension of the first short round bar member 2A.

INDUSTRIAL APPLICABILITY The present invention can be suitably used for a water stop device which is inserted into a pipe body and used to close the middle of the pipe body.

1 Water stop device 2 Core rod
2a Air supply path 3 Balloon
3a One end
3b The other end
3c Intermediate part 4 1st fixture 5 2nd fixture 6 Slide sleeve 7 Seal ring 8 Reinforcing wire 9 Stopper member 10 Wire 11 Fixture 20 Tank 21 1st piping 22 2nd piping 23 Valve

Claims (5)

A water stop device that is inserted into the tube and used to block the middle of the tube.
An elastically stretchable balloon with a tubular shape and an intermediate portion in the central axis direction having a diameter larger than that of one end portion and the other end portion.
A core rod inserted in the entire central axis direction of the balloon and having an air supply passage for supplying pressurized gas into the balloon inside.
First fixing for immovably fixing the one end portion in the central axis direction by being fitted to the outer diameter side of the one end portion of the balloon so that the one end portion is pressed against one end side in the central axis direction on the outer peripheral surface of the core rod. Ingredients and
A slide sleeve that is fitted to the other end side of the outer peripheral surface of the core rod in the direction of the central axis so as to be slidable and displaceable in the direction of the central axis.
A seal ring that makes the fitting surface between the slide sleeve and the core rod airtight,
A second fixture for pressing the other end portion against the outer peripheral surface of the slide sleeve and immovably fixing the other end portion in the central axis direction by being fitted to the outer diameter side of the other end portion of the balloon. Prepare,
The outer diameter of the first and second fixtures is set to be smaller than the inner diameter of the inlet / outlet of the water stop device for the pipe body to be stopped.
The outer diameter of the middle portion in the central axis direction of the balloon when not inflated is set to be equal to or less than the outer diameter of the first and second fixtures.
Inside of the balloon, waterproofing device for its well as extending along the central axis line direction reinforcement wires in several places in the circumferential direction are embedded, the said. The water blocking device according to claim 1 is inserted by suspending and inserting the second fixture in an upward opening of the pipe body to be water-stopped with the second fixture facing down and the first fixture facing up. It is used by
The first fixture is characterized in that a stopper member hooked from above is attached to the peripheral edge of the upward opening of the pipe body to be water-stopped. In the water blocking device according to claim 1 or 2.
The balloon has a two-layer structure laminated in the radial direction, the inner diameter side layer is made of a material having excellent gas impermeable properties, and the outer diameter side layer is made of a material having excellent weather resistance. A water stop device characterized by that. In the water blocking device according to any one of claims 1 to 3.
A water blocking device characterized in that the wall thickness of the intermediate portion of the balloon is set thinner than that of other regions. In the water blocking device according to any one of claims 1 to 4.
A water blocking device characterized in that the wall thickness of one end portion and the other end portion of the balloon is gradually increased toward the end edge, respectively.

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