JP3229196B2 - Sealing plug for leak inspection of existing piping system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for closing a pipe by inserting it into a pipe when an existing pipe system such as a gas pipe or a water pipe is inspected for leaks by an airtight system. The present invention relates to a sealing plug for leak inspection.

[0002]

2. Description of the Related Art An airtight inspection means is known for inspecting an existing piping system for leakage. As a prior art of this airtight type inspection means, for example, as described in Japanese Patent Application Laid-Open No. 63-120237, an expandable and contractible hollow hermetic plug is inserted into a pipe, and this is placed at an appropriate position. After being moved, the hollow hermetic plug is expanded to close the pipe, thereby forming a sealed space between the hollow hermetic plug and the end of the pipe. It is to inspect whether or not.

[0003] When a leak is to be inspected by the above-mentioned prior art, a sealing plug is provided which is movably inserted into a pipe in an inspection section, and which can be expanded by supplying fluid pressure at a required moving position to close the pipe. Is done.

[0004]

The conventional sealing plug used for the airtight inspection has the following problems.

[0005] First, an existing piping system in which a sealing plug is inserted to perform a leak test usually has a plurality of curved pipes such as elbows in the middle of a pipe, and at the position of the curved pipe, there is also a step on the inner surface of the pipe. I do. In a pipe situation where there are many such curved pipe portions and uneven steps, even if the sealing plug is inserted into the pipe and is moved to a predetermined position, it becomes impossible to pass through the bent pipe section or the uneven steps are obstructed. In other words, the sealing stopper cannot be moved to a desired position.

[0006] A conventional sealing plug includes an inflatable body that expands by applying a fluid pressure to close the inside of the pipe, and the inflatable body is formed of an elastic material such as rubber. However, in the above-described piping situation, there are many projections and corners on the inner surface of the pipe, and there is a problem that the expansion body is damaged by the projections and corners during the movement of the sealing plug, and inspection work cannot be performed. .

The present invention has been proposed in order to solve the above-mentioned problems, and it is possible to reliably move any type of piping system to a desired position, and furthermore, to prevent a trouble in a pipe. It is an object of the present invention to provide a sealing plug in which the expansion body is not damaged.

[0008]

In order to achieve the above object, a sealing plug for leak inspection of an existing piping system according to the present invention is inserted into a pipe of an existing piping and expanded when a fluid pressure is applied at a required moving position. A sealing plug that is operated to close the inside of a pipe and to move in the pipe by contracting when fluid pressure is removed, and has the following features.

First, the sealing plug has a shaft body having a fluid pressure supply passage and capable of extending and contracting in the axial direction, and a cylindrical body surrounded by the outer periphery of the shaft body and supplied with fluid pressure from the supply passage. An annularly expanding inflatable body, and a spherical cap divided into two parts before and after the shaft body, wherein when the shaft body is extended, the half-split caps are separated to form a swelling gap of the expandable body; When the body contracts, a half-cap is abutted, and a protective cap is provided on the shaft so as to surround the outer periphery of the inflatable body so as to house the inflatable body therein. A hose for supplying / removing fluid pressure is connected to the supply passage, and an insertion wire for passing the sealing plug into the tube is connected along the outer periphery of the hose.
Here, in a state where the sealing plug is stopped at a required position in the pipe, fluid pressure is supplied to a supply passage of the shaft through a hose, whereby the shaft is extended, the protective cap is separated, and the expansion body is expanded. To inflate the inflatable body that swells from the gap of the protective cap to the pipe inner wall to make the inside of the pipe closed, and also removes fluid pressure from the supply passage of the shaft via a hose. By setting the passage under negative pressure,
The inflatable body and the shaft are contracted, and the protective cap is brought into contact with the protective cap to receive the inflatable body in the protective cap so that the sealing plug is movable.

Secondly, the hose for supplying / removing the fluid pressure is connected to a water supply tank via a pump, and by operating the pump to supply water, the water pressure is supplied to the supply passage of the shaft body as the fluid pressure. Then, the supply passage is brought into a negative pressure state by performing a water absorbing operation of the pump.

Third, a concave portion capable of being filled with grease or the like is formed in the vicinity of the central portion of the outer peripheral surface of the expansion body.

Fourthly, the above-mentioned insertion wire for inserting the sealing plug into the tube is made of a coil spring, and the above-mentioned hose is arranged inside the coil spring.

Fifthly, a guide wire made of a coil spring is connected to the shaft body at the front side in the traveling direction to be inserted into the pipe, and a ring member is attached to the tip of the guide wire. The guide wire is configured so that the front half in the traveling direction can be bent more flexibly than the rear half.

[0014]

The above sealing plug has a shaft at the center, an inflatable body is installed so as to cover the side surface of the shaft, and a spherical protective cap is provided so as to surround the outer periphery of the inflatable body. . The shaft body has a structure that expands and contracts in the axial direction. One half of the protective cap divided into two parts is attached to the front of the shaft body, and the other half part is attached to the rear, and the shaft body expands and contracts. Then, the protection cap operates so that the half-split portions are separated from or come into contact with each other. Further, a fluid pressure supply passage is formed inside the shaft body, and this supply passage is open to the pressure filling space of the expansion body, and surrounds the shaft body by applying fluid pressure to the supply passage of the shaft body. The expanding body that expands performs the expanding operation.

In order to close the inside of the pipe by stopping the sealing stopper at a desired position, fluid pressure is supplied to the supply passage of the shaft. The pressure expands the inflatable body, and the inflating action causes the shaft body to expand, so that the protective caps are separated from each other to form a swelling gap of the inflatable body therebetween. Further, by supplying a fluid pressure, the inflatable body swelling from the gap between the protective caps expands in a cylindrical annular shape and seals the inner surface of the tube. At this time, when the inflatable body contracts, a recess is formed in the outer peripheral surface of the inflatable body near the center corresponding to the gap between the protective caps, and the recess is filled with grease or the like. This reduces the resistance when swelling out of the gap of the protective cap, and protects the contact surface when expanding and closely adhering to the inner surface of the pipe by interposing grease or the like. The sealing effect is enhanced.

At the time of movement of the sealing plug, the fluid pressure in the supply passage of the shaft is eliminated, and further, a negative pressure is applied, so that the inflatable body contracts, and the contracting action causes the shaft to which the inflatable body is attached to contract. . Then, as described above, the half-split portions of the protective cap abut each other due to the contraction of the shaft, and the inflatable body is completely housed in the protective cap, thereby preventing damage to the inflatable body. In addition, since the protective cap forming the outer shell of the sealing plug has a spherical shape, there is little resistance or snagging when the sealing plug is inserted or moved, and good penetration can be ensured.

Here, the opening and closing operations for separating and abutting the protective caps from each other need only be operations of supplying and removing the fluid pressure to the inflatable body, so there is no need to perform any separate operation, and the protective cap is provided. The operation does not become complicated.

A hose connected to the shaft for supplying and removing fluid pressure to and from the supply passage of the shaft is provided with an insertion wire around the hose, and the insertion wire is inserted through a sealing plug. As well as protecting the hose. In addition, by forming the insertion wire with a coil spring, it is possible to perform flexible and reliable insertion into a pipe having a straight portion and a bent portion.
Further, by using the water pressure as the fluid pressure, the expansion / contraction operation of the shaft body and the opening / closing operation of the protection cap can be performed more reliably. At this time, the supply and elimination of the water pressure are performed by switching the water supply operation and the water absorption operation of the pump.

Furthermore, a guide wire made of a coil spring is connected to the front side in the traveling direction for inserting the shaft body into the pipe, so that the penetrability when passing through a curved pipe portion such as an elbow is further improved. A ring member is attached to the tip of the guide wire, and the coil spring allows the front half in the traveling direction to bend more flexibly than the rear half. In this way, when the guide wire reaches the curved tube, the ring at the tip avoids the obstruction of insertion, and the guide wire itself gradually curves from the tip, so that the smooth insertion along the curve of the curved tube is possible. Will be possible.

[0020]

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

FIG. 1 is a sectional view showing a sealing plug for leak inspection of an existing piping system according to an embodiment of the present invention. In the figure,
Reference numeral 10 denotes a shaft body, which includes a front part 10a and a rear part 10b. The front part 10a of the shaft body 10 is formed with a convex part rearward,
A concave portion is formed in the rear portion 10b in front of which the convex portion of the front portion 10a fits, and the entire length of the shaft body 10 is formed to be expandable and contractible in the front-rear direction by slidably fitting the concave and convex portions. ing.

An inflatable body 11 is mounted on a side surface of the shaft body 10 so as to straddle a front portion 10a and a rear portion 10b. The inflatable body 11 is formed of an elastic material such as rubber, and natural rubber (NR) and styrene-butadiene rubber (S
BR) synthetic rubbers are suitable. The form of the expansion body 11 is a barrel-shaped cylindrical body, the front end of which is a front part 10 a of the shaft body 10.
The rear end portions are hermetically attached to the rear portion 10b. A concave portion 1 is provided on the outer periphery of the central portion of the expansion body 11.
1a is formed, and the recess is filled with grease.

Further, a protective cap 12 is attached to the outer peripheral surface of the shaft body 10. The protective cap 12 is made of metal or hard resin, and is generally spherical as a whole.
The front half-split cap 12 which is divided into two parts at the center
a and the rear half-cap 12b are abutted. The front half-split cap 12a is
The rear half-cap 12b is attached to the front
0 is attached to the rear part 10b, respectively, and the protective cap 1
2 as a whole surrounds the outer periphery of the expansion body 11.

A passage 10c for supplying fluid is provided inside the shaft 10, and the passage 10c is
Open into the fluid-filled space of the expansion body 11 on the side surface. A hose 13 connected to the passage 10c is attached to the rear of the shaft body 10, and an insertion wire 14 made of a coil spring is attached to the outer periphery of the hose 13. A guide wire 15 is mounted forward of the shaft 10 in the traveling direction.

Next, FIGS. 2A and 2B show two embodiments of the guide wire 15. FIG. The guide wire 15 has a coil spring 21 attached to the tip of the front portion 10a of the shaft, and a ring member 20 attached to the tip of the coil spring 20. In the example of FIG. 2A, the front half 21a of the coil spring 21 in the traveling direction is formed by a single coil spring, and the rear half 21b is formed by a double coil spring. FIG. 2
In the example of (b), the pitch of the first half 21a of the coil spring 21 in the traveling direction is coarse, and the pitch of the second half 21b is dense. In this manner, the guide wire 15 is configured to be able to bend more flexibly than the rear half portion 21b of the coil spring 21 in the guide wire 15, and the leading end is provided with a ring member, so that the guide wire 15 reaches the curved portion of the conduit. In some cases, the obstruction of insertion is avoided by the ring member at the distal end, and the guide wire itself gradually curves from the distal end portion, enabling smooth insertion along the bend of the curved tube portion.

FIG. 3 shows an example of an apparatus configuration for supplying and removing fluid pressure to and from the sealing stopper via the hose 13.
30 is a water tank, 31 is a pump, 32 is a pressure gauge, 33
Denotes a relief valve and 35 to 37 denote stop valves. A piping system connected to a water supply tank 30 via a pump 31 is connected to a hose 13 provided inside the insertion wire 14. The pump 31 is a manually operated reciprocating pump that performs a compression or suction operation as shown by an arrow, and selectively opens and closes stop valves 36 and 37 at this time to supply water to the hose 13 and seal the stopper. , Or absorbs water from the hose 13 and supplies a negative pressure to the sealing stopper. Pressure setting of pressurization is set to 4.5kg / cm ² ~5.0kg / cm ² by the relief valve 33. Further, a lock mechanism is provided on the handle portion of the pump 31 so that the operation of the pump 31 is locked at the time of compression or suction of the pump 31 so that the supply pressure state can be maintained.

Next, the operation or use of the embodiment will be described with reference to FIGS.

First, in order to perform a leak inspection of an existing pipe, a section having a predetermined length which can be assumed to be leaking is specified, and both ends of the pipe in the section are opened. Then, a sealing plug is inserted from one end in the state of FIG. In this state, since the inflatable body 11 of the sealing plug is housed in the protective cap 12, the inflatable body 11 is not damaged even if a projection or the like is present in the conduit, and the spherical protective cap 12 is Since it is the outer shell of the sealing stopper, smooth movement without resistance or snagging is possible. Also, by the action of the guide wire 15 provided in the direction of travel of the sealing plug, even if there is a curved pipe portion, smooth insertion is performed along the form of the conduit.

Normally, a sealing stopper is inserted to the vicinity of the middle of the inspection section and fixed at that position. Then, the stop valve 36 in front of the water supply tank 30 is opened, and the pump 31 is sucked to take water into the cylinder of the pump. Then, the stop valve 36 is closed, and the stop valve 37 is opened. In this state, the pump 31 is compressed to supply water and pressurize the water through the hose 13 to the supply passage 10c in the shaft 10 of the sealing stopper. As a result, the expansion body 11 slightly expands, and the expansion body expands the shaft body 10, whereby the half-split caps 12 a and 12 b of the protection cap 12 are separated from each other to form a gap therebetween. When further pressurized, the expanded body 1
Numeral 1 swells from the above-mentioned gap and bulges into a cylindrical annular shape (tire tube shape) to closely adhere to the inner surface of the pipeline to close the pipeline. At this time, by filling the concave portion 11a on the outer periphery of the expansion body 11 with grease, the resistance when the expansion body 11 swells from the gap of the protective cap is reduced, and when the expansion body 11 expands and comes into close contact with the inner surface of the pipe. Is protected by the presence of grease, and the sealing effect is enhanced by the presence of grease.

When the blockage of the pipeline by the sealing stopper is completed,
An opening at the end of the pipeline on the side where the sealing plug is inserted is closed, and an airtightness test is performed to check the pressure state in the closed space by supplying air pressure to the closed space formed in the pipeline. As a result of this airtightness inspection, if a leak is confirmed in the closed space in the pipeline, the sealing plug is moved forward by a predetermined distance in order to identify the leaked portion, and the above airtightness inspection is sequentially performed. . If no leaks are found after the first leak check,
The same operation is performed by removing the sealing stopper and reinserting it from the opposite end of the conduit.

Here, in order to make the sealing stopper movable from the closed state to the movable state, the stop valve 36 shown in FIG. 3 is closed, the stop valve 37 is opened, and the pump 31 in this state is opened.
Is sucked to return the water sent into the expansion body 11 of the sealing stopper to the cylinder of the pump 31. As a result, the inflatable body 11 contracts, but by further suctioning, a negative pressure is applied to completely contract the inflatable body 11 to be housed in the protective cap and return to the state of FIG.

[0032]

Since the present invention is configured as described above,
The following effects are obtained. (1) By covering the outer shell of the sealing plug with a spherical protective cap, smooth insertion can be obtained even in a pipe system having a curved pipe portion or an uneven portion. (2) Since the inflatable body is covered and protected by the protective cap when the sealing plug is moved, breakage of the inflatable body can be prevented. (3) The opening / closing operation for separating and contacting the protective cap only requires the operation of supplying and removing the fluid pressure to the inflatable body. Therefore, even if the protective cap is provided, the operation does not become complicated. (4) By connecting an induction wire made of a coil spring to the front side in the traveling direction of the sealing plug, the penetrability when passing through a curved pipe portion such as an elbow can be further improved. (5) A ring member is attached to the tip of the guide wire, and the coil spring of the guide wire is configured to bend the front half in the traveling direction more flexibly than the rear half. At this time, the obstruction of the insertion is avoided by the ring at the distal end, and the guide wire itself gradually curves from the distal end portion, thereby enabling smooth insertion along the bend of the curved tube portion. (6) An insertion wire is provided around the hose connected to the shaft for supplying and removing fluid pressure to and from the supply passage of the shaft, so that the sealing plug can be inserted by the insertion wire. This is ensured and the hose is protected by the insertion wire. (7) In addition, by forming the insertion wire with a coil spring, it is possible to perform flexible and reliable insertion in a form of a pipe having a straight portion and a bent portion.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a sealing plug for leak inspection of an existing piping system according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing an embodiment of a guide wire.

FIG. 3 is an explanatory diagram showing a device configuration for supplying and eliminating fluid pressure in a sealing plug for leak inspection of an existing piping system according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 shaft body 10a front part 10b rear part 11 inflatable body 11a concave part 12 protective cap 12a, 12b half-split cap 13 hose 14 insertion wire 15 guide wire 20 ring part 21 coil spring 30 water supply tank 31 pump 32 pressure gauge 33 relief valve 35, 36 , 37 stop valve

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuhiro Ozawa 204-9, Oizumi-ji, Kasugai-shi, Aichi Prefecture (72) Inventor Masao Kimura 26, Yokocho, Inuyama-shi, Aichi Prefecture (72) Inventor Keijiro Hori Minami Edogawa-ku, Tokyo Kasai 7-2-5-704 (56) References JP-A 63-107838 (JP, U) JP-A 54-135988 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) ) G01M 3/28 G01M 3/26

Claims (6)

(57) [Claims] When a fluid pressure is applied at a required moving position, the pipe is inserted into an existing pipe and expands to close the pipe. When the fluid pressure is removed, the pipe is contracted to move in the pipe. A sealing stopper, wherein the sealing stopper has a fluid pressure supply passage and an axially expandable / contractible shaft, and a cylindrical ring surrounded by an outer periphery of the shaft and supplied with fluid pressure from the supply passage. An expanding body that expands, and a spherical cap that is divided into two parts before and after the shaft body, wherein when the shaft body is extended, the half-split caps are separated to form a swelling gap of the expandable body; A protective cap installed on the shaft surrounding the outer periphery of the inflatable body so that the half-split cap abuts during contraction to house the inflatable body therein, Hose that supplies and removes fluid pressure to and from the supply passage And a connecting wire for passing the sealing plug into the pipe along the outer periphery of the hose, and moving the sealing plug to a required position in the pipe and stopping the pipe, and supplying the shaft with a supply passage through the hose. By supplying fluid pressure to the pipe, the shaft body is extended, the protective cap is moved away, and the inflatable body is inflated, so that the inflatable body bulging out of the gap of the protective cap is brought into close contact with the inner wall of the pipe, and the inside of the pipe is closed. The closed state is established, and the fluid pressure is removed from the supply passage of the shaft through the hose to make the passage a negative pressure state, so that the inflatable body and the shaft are contracted and the protective cap is brought into contact with the protective cap for protection. A sealing plug for leak inspection of an existing piping system, wherein an expansion body is housed in a cap and the sealing plug is made movable. 2. A hose for supplying / removing the fluid pressure,
The pump is connected to a water supply tank via a pump, and the pump is operated to supply water to supply water pressure as a fluid pressure to the supply passage of the shaft body, and the pump is operated to absorb water so that the supply passage is in a negative pressure state. The sealing plug for leak inspection of an existing piping system according to claim 1. 3. In the vicinity of the center of the outer peripheral surface of the expansion body,
The sealing plug for leak inspection of an existing piping system according to claim 1 or 2, wherein a concave portion capable of being filled with grease or the like is formed. 4. The wire according to claim 1, wherein the insertion wire for inserting the sealing plug into the tube comprises a coil spring, and the hose is disposed inside the coil spring.
The sealing plug for leak inspection of an existing piping system according to any one of claims 3 to 3. 5. The guide body according to claim 1, wherein a guide wire made of a coil spring is attached to a front side of the shaft body in a traveling direction to be inserted into the pipe, and a ring member is provided at a tip end of the guide wire. The sealing plug for leakage inspection of an existing piping system according to any one of the above. 6. The sealing plug for leak inspection of an existing piping system according to claim 5, wherein the guide wire has a structure in which a front half portion in a traveling direction can be bent more flexibly than a rear half portion.