JPH0814474A - Air-tightness inspecting seal device for pipe line - Google Patents

Abstract

PURPOSE:To provide an air-tightness inspecting seal device such as capable of specifying a leak part, and to provide an air-tightness inspecting seal device preventing a seal means from receiving damage in the case of inserting the seal means into a pipe line. CONSTITUTION:In an air-tightness inspecting seal device 10 inspecting air- tightness by conveying a seal means 20 to a prescribed part from an opening end part in a pipe line 6 having a bending part and step difference in the halfway and by closing the pipe line air-tightly shut off, the device has a pipe line insertion device 11 inserting a long scaled closely wound coil wire 16 delivered or retracted while rotated by a screw-shaped propelling mechanism 18 into the pipe line 6. In the point end of the coil wire 16 of this pipe line inserting device 11, a protective cover 21 for the seal means 20 is mounted, to contract a balloon type seal unit 22 stored automatically in the protective cover 21, and the seal unit 21 is provided in a manner wherein it is sprung out from the protective cover 21 and expanded to close the pipe line 6 air-tightly shut off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device for airtightness inspection of a pipeline, which is applied when leak-checking a buried pipeline such as a gas pipeline or a water pipeline.

[0002]

2. Description of the Related Art In buried pipes such as gas pipes and water pipes buried in the ground, when the pipes are metal pipes, the pipes deteriorate over time and become corroded, which leads to corrosion and rust. As a result, a defective portion such as a pinhole may be generated and leakage may occur. As a solution to this problem, we propose a pipeline rehabilitation repair method such as lining the inside of the pipe by introducing liquid resin etc. or lining the seal hose or tube, etc., while the pipe is buried. Has been done.

This rehabilitation repair of the pipeline is originally intended to prevent leakage and prevent maintenance, and it is desired to apply rehabilitation repair technology to the leak-free pipeline to rehabilitate the pipeline, but leakage has already occurred. In the case of a pipeline, it may be necessary to identify the leak location and perform partial leak repair.

Conventionally, as a method of inspecting whether or not a leak has occurred in a pipeline, a gap between one end opening and the other end opening of the pipeline is sealed, and a gas such as air is introduced into this pipeline. There is known an airtightness inspection method in which the inside of the pipeline is made a high-pressure atmosphere by doing so, and the leak is checked by detecting the leak of gas in this case. Further, as an inspection method of this kind, conventionally, for example, as described in Japanese Utility Model Application Laid-Open No. 54-99120, an airbag is inserted from the opening end of the pipeline, and the airbag is inflated at a predetermined position of the pipeline. There is also known a technique for sealing a pipe line.

[0005]

By the way, in the conventional airtightness inspection method, both ends of the pipeline to be checked for leakage at the time of its construction are cut, and the pipeline having a required length between two points is sealed to perform the leakage check. Since this is a method, it is possible to check the leakage over the entire length of the pipeline, but it is not possible to identify the location of the leakage that occurred in the pipeline, and two openings are excavated during the construction work. Since it is necessary to do so, there is also a disadvantage that the construction time and cost are high.

Further, in order to carry out an airtight inspection capable of identifying the leaked portion, a method of inserting the air bag disclosed in the above-mentioned Japanese Utility Model Laid-Open No. 54-99120 into the pipeline is conceivable. In this case, Causes a problem that the airbag may be damaged by being caught by a connecting member such as an elbow and a socket provided in the pipeline, and as a result, the airbag cannot be inflated to properly seal the pipeline. To do.

In view of the above problems, it is a first object of the present invention to provide a sealing device for an airtightness test capable of identifying a leak point, and the sealing means is inserted into a pipe line. A second object of the present invention is to provide a sealing device for airtightness inspection, in which the sealing means is not damaged.

[0008]

In order to achieve the above-mentioned object, the present invention has a state in which the pipe is moved from one end opening portion of the duct into the pipe, and when the pipe is constricted, the pipe is reduced in diameter from the pipe inner diameter and expanded. In the above, it is premised on a sealing device that inserts a balloon-type seal body that is larger than the inner diameter of the pipe and is in close contact with the inner surface of the pipe, moves the seal body to an appropriate position in the pipe and expands it, and airtightly shuts off the inside of the pipe. . And at the one end opening portion of the above-mentioned conduit, it has a coil wire insertion device for feeding or pulling back a long tightly wound coil wire into the pipe while rotating it by a screw-shaped propulsion mechanism, and at the tip of the coil wire of the insertion device, A protective cover having a U-shaped cross-section whose outer diameter is smaller than the inner diameter of the pipe and whose distal end is open is connected, and the sealing body is accommodated in the U-shaped cross-section when expanded and expanded. It should be installed so that it pops out from the U-shaped cross section and expands in the opened state, and the seal body is connected to a fluid hose that can be operated to introduce and discharge gas or liquid. It has a feature.

Further, in the present invention, the seal body has an axially stretchable fiber portion and a circumferentially stretchable fiber portion which are integrally formed on the outer peripheral side, and the inside is coated with a highly airtight rubber material. It is one of the other features that it has the tube which becomes.

In the present invention, when the coil spring is attached to the tip of the wire of the coil wire insertion device, the protective cover and the seal body may be attached to the tip of the coil spring. It is desirable that the seal body be formed so as to expand and contract in the axial direction and the circumferential direction so as to come in and out of the protective cover, but the sectional shape thereof is not particularly limited to the U shape.

[0011]

In the sealing device constructed as described above, the tip of the wire fed from the coil wire insertion device is inserted into the conduit of the required length to be checked for leakage from the one end opening of the conduit during the airtightness inspection. To do. At this time, since the coil wire is being fed while rotating, the protective cover and the seal body attached to the tip of the wire can be surely inserted to a required position even in a duct having a bent portion or a step.

At the time of this insertion, the seal body provided at the tip of the coil wire is in a constricted state by draining fluid,
Since it is accommodated in the U-shaped cross section of the protective cover, even if there is a bend or a step in the pipe line, the seal body will not directly contact the inner wall of the pipe and the seal body will not be damaged by the protective cover. Protected and properly delivered to the required position in the pipeline.

Stop loading at an appropriate position in the pipeline,
Then, when the fluid is introduced into the seal body at high pressure, the seal body jumps out of the U-shaped cross section of the protective cover and expands, so that the seal body is in close contact with the inner surface of the pipe to be airtightly blocked. In this state, one end of the pipeline is also closed, and the pipeline in the section blocked and sealed by the seal body is made into a high-pressure atmosphere, and by detecting the pressure drop, is there a leak defect in the pipeline? It becomes possible to detect whether or not.

At the time of this inspection, the position of the tip of the coil wire (the position of the protective cover and the seal body connected to the end of the wire) is appropriately selected in the pipe line to be leak checked, and a plurality of positions are selected. By performing the airtightness inspection at, it is possible to identify the leakage location.

Further, the seal body is formed by integrating a fiber portion that expands and contracts in the axial direction on the outer peripheral side and a fiber portion that expands and contracts in the circumferential direction, and a tube formed by coating a highly airtight rubber material on the inside. When the seal body is expanded in the closed position, the expansion of the fiber portion that expands and contracts in the axial direction ensures that the seal body protrudes from the protective cover, and the expansion of the fiber portion that expands and contracts in the circumferential direction causes the seal body to expand. Is obtained so as to be surely brought into close contact with the inner surface of the pipe, and the blockage in the pipe line is appropriately performed.

Furthermore, if the expansion / contraction ratio is changed between the axially stretchable fiber portion integrated on the outer peripheral side of the seal body and the circumferential stretchable fiber portion, the shape of the seal body is expanded when the seal body is expanded. Changes to a shape suitable for the sealing action, and the blocking and blocking of the inside of the pipeline can be performed more accurately, and at the same time,
It is possible to prevent the inner tube made of rubber from bursting due to excessive expansion.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. First, referring to FIG. 1, the overall configuration of an embodiment suitable for the airtightness inspection method of a pipeline will be described. Reference numeral 1 is a conduit such as a gas pipe or a water pipe that is buried underground at a predetermined depth such as a road. A supply pipe 3 is connected from the conduit 1 to a consumer through a branch metal fitting 2 such as a service tee. The supply pipe 3 extends horizontally from the road side to the residential land side of the demand destination in a buried state in the ground, and is connected to the bent elbow 4 and the standing pipe 5 standing on the ground.
Then, a gas meter (not shown) is attached to the vertical pipe 5,
It supplies gas and other products to customers.

In such a pipe, when the pipe line 6 of the supply pipe 3, the elbow 4 and the vertical pipe 5 which are connected to each other after the branch fitting 2 is a metal pipe, it is corroded due to long-term laying and a leak defect portion is generated. It tends to occur. Therefore, the airtightness inspection seal device of the present invention is used particularly for airtightness inspection of the entire area of the conduit 6.

In order to perform the airtightness test, the gas meter or the like communicating with the standpipe 5 is removed, and the sealing device 10 is attached to the connecting pipe 7 such as the elbow. Further, after the sealing work is completed, the inspection device 30 described later is attached to the connecting pipe 7.

The sealing device 10 comprises a conduit insertion device 11, a sealing means 20, and a seal operating device 25. The conduit insertion device 11 is mounted in the main body 12 so that the storage container 13 is rotated or stopped by the motor 14 and the brake 15, and the coil wire 16 is stored in the storage container 13 so that the coil wire 16 can move in and out. The coil wire 16 is a long, tightly wound coil wire rod in which the wire 16a is closely wound in a spiral shape as shown in FIG. 2, has a relatively strong elasticity and bendability, and is wound around the entire length by tight winding. A spiral groove 16b similar to a screw is formed in the. As shown in FIG. 2, a coil spring 17, which is not closely wound, is attached to the tip of the coil wire 16 so that the coil spring 17 easily swings and exhibits excellent insertability. A screw-shaped propulsion mechanism 18 is provided in the main body 12 immediately before the wire entry / exit portion 13a of the storage container 13 so that the projection 18a as a nut is engaged with the groove 16b of the coil wire 16 to rotationally propel it.

With the configuration of the conduit insertion device 11, when the motor 14 is driven by the control device 19 to rotate the coil wire 16 together with the storage container 13 to one side, the propulsion mechanism 18
The coil wire 16 is fed out while being sequentially rotated by the engagement between the fixed-side protrusion 18a and the spiral groove 16b of the coil wire 16. By this rotation propulsion, the coil wire 16 surely advances in the inside of the pipeline 6, bends in accordance with its shape due to its bendability, and easily bends over the gap due to elasticity at the step etc. It becomes possible to move to and insert. When the motor 14 rotates the coil wire 16 together with the storage container 13 in the reverse direction, the coil wire 16 is reversely drawn by the propulsion mechanism 18 and moves backward from the conduit 6, and is automatically stored in the storage container 13. By thus automatically inserting the coil wire 16 into the pipe line 6, the tip end of the coil wire 16 is surely inserted to the required position, and the length of the pipe line, the detection of the bent portion, the internal inspection, the obstacle, etc. It is possible to perform various operations such as removal.

As shown in FIG. 2, the sealing means 20 is detachably attached with a protective cover 21 having a U-shaped cross section, the distal end of which is open, at the distal end of the coil spring 17 at the tip of the coil wire 16. Sealing body 2 inside 21
Two are provided. The sealing body 22 has a fiber portion 22a that expands and contracts in the axial direction and a fiber portion 2 that expands and contracts in the circumferential direction on the outer peripheral side.
2b are integrally formed with each other, and a tube formed by coating a highly airtight rubber material is provided inside, and further, a flexible tube 23 for taking in and out gas such as air into and from the fiber portion 22a is provided. Connected and formed.

In the fibers integrated on the outer peripheral side of the seal body 22, the expansion / contraction ratio between the axially elastic fiber portion 22a and the axially elastic fiber portion 22b is changed,
When air or liquid is introduced at a high pressure, the seal body 22 first extends in the axial direction and protrudes forward from the protective cover 21 and expands in a spherical shape larger than the inner diameter of the tube in the circumferential direction as shown by the dashed line in the figure. The shape of the seal body 22 is adjusted so as to change to a shape suitable for the sealing action in the pipe. When the air is removed, both fiber portions 22a and 22b contract due to the expansion and contraction characteristics as shown by the solid line in the figure, and are automatically stored in the protective cover 21.

In the seal actuating device 25, the tube 23 of the sealing means 20 is inserted all over the inside of the coil wire 16, and the tube 23 is taken out from the rear end of the container 13. Then, the tube 23 is connected to a pump 26, a pressure gauge 27, etc., and air or liquid is introduced into or withdrawn from the seal body 22 at a high pressure to perform a sealing operation.

The inspection device 30 has a hermetically sealed body 31 including the coil wire 16 and hermetically mounted at the open end of the connecting pipe 7, and a pump 32, a pressure gauge 33, etc. are connected to the hermetically sealed body 31. . Then, in a state where both ends of the pipeline 6 are hermetically sealed by the seal body 22 and the sealing body 31, the pipeline 6 is pumped by the pump 32.
Air is supplied to the interior at a pressure lower than the seal pressure to inspect whether a leak defect has occurred.
The seal actuating device 25 and the inspection device 30 may be shared by the pump, pressure gauge, and the like.

Next, the work procedure of the airtightness inspection will be described. First, in the sealing device 10, the protective cover 21 and the sealing body 22 of the sealing means 20 are attached to the tip of the coil spring 17 of the duct insertion device 11, the tube 23 is passed through the entire inside of the coil wire 16, and the end portion is stored. Take it out of the container 13 and prepare it. Then, the gas meter of the standing pipe 5 of the pipeline 6 to be inspected is removed, the pipeline inserting device 11 is installed near the connecting pipe 7, and the tip of the coil wire 16 of the pipeline inserting device 11 is inserted into the pipeline 6. To do.

Thereafter, when the motor 14 of the conduit insertion device 11 is driven to rotate in one direction, the coil wire 16 rotates together with the storage container 13 and the coil wire 16 is driven by the propulsion mechanism 18.
The coil wire 16 is rotated and propelled in the conduit 6 while being guided by the swinging action of the flexible coil spring 17. That is, the coil wire 16 is bent from the upright tube 5 into the elbow 4 according to the shape of the coil wire 16, and is easily passed over the step of the tube connecting portion or the like to be further inserted into the supply tube 3, whereby the tip of the coil wire 16 is inserted. The sealing means 20 attached to the is sequentially conveyed in the pipe line 6. In this case, since the sealing body 22 of the sealing means 20 is deflated and accommodated in the protective cover 21 by being deflated, the sealing body 22 is sealed.
Are easily transported. Also, the elbow 4 of the coil wire 16
When the first sealing means 20 is inserted when the protective cover 2 is inserted.
Only 1 moves in contact with the inner surface of the pipe and the like, and thereby the seal body 22 inside the protective cover 21 is protected from damage.

Here, the spiral groove 16 of the coil wire 16 is provided.
The moving speed of the coil wire 16 is calculated from the pitch of b and the rotation speed. Further, since the pipe length from the connecting pipe 7 to the vicinity of the branch fitting of the supply pipe 3 is known in advance, the arrival time is calculated by the moving speed of these coil wires 16 and the pipe length. When the brake 15 stops the rotation and propulsion of the coil wire 16 after a predetermined time has elapsed, the sealing means 20 at the tip of the coil wire 16 causes the seal portion 20 near the branch fitting of the supply pipe 3 in the innermost part of the pipeline 6 to seal. Will definitely reach.

Thereafter, the end of the tube 23 of the sealing means 20 is connected to the pump 26 of the seal actuating device 25, and the air or liquid A is introduced into the seal body 22 at high pressure. Then, as shown in FIG. 3, the seal body 22 jumps forward from the protective cover 21 and swells in a spherical shape, and the seal body 22 pressurizes and adheres to the inner surface 3a of the supply pipe 3 to surely keep it closed and blocked. To be done.

In this state, a sealing body 31 is further attached to the open end of the connecting pipe 7 to seal it, and a pump 32 of the inspection device 30 is installed.
And the pressure gauge 33 are connected. Then, the pump 32 supplies the air B to the inside of the conduit 6 at a pressure lower than the sealing pressure to pressurize the air. Then, the high-pressure air B spreads over the entire area of the pipeline 6 extending from the supply pipe 3 to the connecting pipe 7 via the elbow 4, the standing pipe 5, and the like,
For example, in the case of a gas pipe, the high pressure atmosphere is close to the actual gas usage state.

Therefore, in the high pressure atmosphere state of the pipe 6, the pressure gauge 3
The airtightness inspection is carried out by detecting the pressure change by 3. That is, when there is no pressure change by the pressure gauge 33, it is confirmed that there is no leakage defect portion substantially corresponding to actual gas leakage. Further, if there is a defective portion 6a at any part of the pipe line 6 as shown in the drawing, the air B escapes from the defective portion 6a, and a pressure drop occurs. Therefore, when there is a pressure drop by the pressure gauge 33, it is confirmed that the defective portion 6a corresponding to substantially actual gas leakage is generated. Thus pipeline 6
, The position of the seal body 22 is appropriately selected in the pipeline to be checked for leakage,
By selecting a plurality of locations and performing an airtight inspection, it becomes possible to identify the leakage location.

After completion of the airtightness inspection, the pipe 6 is opened to the atmosphere to remove the air A, and the tube 23 of the sealing body 22 is also opened to the atmosphere to remove the air B. Then, the seal body 22 contracts due to the expansion and contraction characteristics and is automatically housed inside the protective cover 21. Then, when the motor 14 of the conduit insertion device 11 is rotated in the opposite direction, the coil wire 16 is pulled backward by the propulsion mechanism 18, moves backward from the conduit 6, and is automatically stored in the storage container 13 sequentially. At this time, as the coil wire 16 moves backward, the sealing body 22 of the sealing means 20 at the tip of the coil wire 16 is moved.
Is also safely transported to the connecting pipe 7 side. In this way, the coil wire 16 of the conduit insertion device 11 is inserted into the conduit 6, and then pressure is applied to the seal body 22 and the conduit 6, whereby the conduit 6 can be easily airtightly checked in a dry state.

In the case of locally performing a fine airtight inspection of a long pipe line 6, the work of sealing and inspecting with a gas is repeated at a plurality of coil wire insertion points in the pipe line 6 to easily make the airtightness. To be inspected. As a result, the accuracy of the airtight inspection is improved, and the location of the leak defect portion of the pipeline 6 can be accurately known.

[0034]

As described above, according to the present invention,
The seal device for airtightness inspection has a conduit insertion device that extends or retracts a long closely wound coil wire by a screw-shaped propulsion mechanism to insert the coil wire into the conduit, and the coil wire of the conduit insertion device. Since the seal means is attached to the tip of the seal means, the seal means can be accurately conveyed to a predetermined portion of the pipeline having a bent portion or a step in the middle thereof. The sealing means is a balloon cover on the protective cover.
It is constructed so that it contracts and is automatically stored in the protective cover, and it pops out from the protective cover and expands to airtightly block and block the pipeline, so it is safe without damaging the seal inside the pipeline. It can be transported, and at the time of airtightness inspection, the pipe can be surely blocked and closed by the seal body, which is highly practical.

At the time of the airtightness inspection, the coil wire of the conduit insertion device is simply inserted into the conduit, and then pressure is applied to the seal body and the conduit, so that the work is very simple and the workability is improved. . In particular, it is advantageous when a pipe is locally and finely inspected for airtightness. Moreover, since the pipeline is airtightly checked in a dry state, it can be applied to a gas pipe or the like.

When the sealing body of the sealing means is formed by integrating the longitudinal fiber portion and the circumferential fiber portion and changing the expansion / contraction ratio thereof, the protective cover is provided when the sealing body is contracted or expanded by air pressure. You can get in and out as appropriate. Therefore, it becomes possible to satisfy both the protection of the sealing body and the sealing performance.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of an airtightness inspection seal device according to the present invention.

FIG. 2 is a cross-sectional view showing a part of a conduit insertion device and a sealing means.

FIG. 3 is a cross-sectional view showing a working state of the airtightness test.

[Explanation of symbols]

 6 Pipe 10 Sealing Device 11 Pipe Inserting Device 16 Coil Wire 18 Screw Propulsion Mechanism 20 Sealing Means 21 Protective Cover 22 Sealing Body

Claims (4)

[Claims] 1. A balloon-type device that moves into the pipe from one end opening of the pipe passage, shrinks from the pipe inner diameter to move inside the pipe when expanded, and expands from the pipe inner diameter to intimately contact the inner surface of the pipe when expanded. In a sealing device that inserts a seal body and moves the seal body to an appropriate position in the pipe to expand the pipe to hermetically block and close the inside of the pipe, a long tightly wound coil wire is provided at one end opening of the pipe line. It has a coil wire insertion device that pays out or pulls back into the pipe while rotating by a screw-shaped propulsion mechanism, and has a U-shaped cross section in which the outside diameter is smaller than the pipe inside diameter and the tip direction is open at the tip of the coil wire of the insertion device. A protective cover is connected, and the protective cover is mounted in the U-shaped cross section when the seal body is narrowed, and is attached so as to protrude from the U-shaped cross section and expand when expanded. , And seal , The inside introducing a gas or liquid drainable the conduit air tight inspection seal device characterized by comprising connecting the fluid hose to be operated. 2. The seal body is provided on its outer peripheral side with a tube formed by integrating a fiber portion that expands and contracts in the axial direction and a fiber portion that expands and contracts in the circumferential direction, and coats a highly airtight rubber material inside. The sealing device for airtightness inspection of a pipe line according to claim 1, wherein 3. The fibers integrated on the outer peripheral side of the seal body change the expansion / contraction rate between the axially expandable / contractible fiber part and the circumferentially expandable / contractible fiber part so that the shape of the seal body is expanded during expansion. 3. The sealing device for airtightness inspection of a pipeline according to claim 1, wherein the sealing device is formed so as to change into a shape suitable for a sealing action. 4. The fluid hose connected to the seal body is drawn out from the insertion device through a coil wire, and its end is connected to a fluid introducing / exhausting mechanism. 3. A sealing device for airtightness inspection of a pipeline according to 3.