TWI502182B - Leakage detection method and device of piping - Google Patents

Description

Leakage detection method and device thereof

The present invention relates to a leak detecting method for detecting a leaking portion of a portion represented by a joint portion of a large diameter pipe buried in a ground and allowing a fluid to pass through, and other portions for early detection. Its device.

In general, pipes used for agricultural water, industrial water, water pipes, and the like are generally used as large diameter pipes (700 φ or more) having an inner diameter to which an operator enters.

As time passes, the fluid flowing inside the pipes leaks from perforations caused by poor joints or other corrosion of the pipe joint portion of the pipe, and the like, the groundwater flows into the pipe, etc. Bad situation.

Especially for pipes buried in the ground, it is not easy to find out the leaking parts.

In the past, by making the inside of the pipe empty, the both ends of the pipe were sealed, and a pressure fluid such as water or air was injected into the inside to observe the leakage state of the damaged portion, thereby judging whether or not there was damage.

However, in the above-described prior inspection method, even if it is possible to grasp the presence or absence of leakage of a fluid, it is difficult to specify not only the leaked portion but also a large amount of time and procedures in the detection of the leak.

[Advanced technical literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2004-125628

The present invention has been made in view of the above-described aspects, and an object of the present invention is to enable a portion of a leak occurrence portion of a pipe to be quickly and reliably found.

In the pipe which has a pipe diameter which can be accessed by an operator and which is used to allow a fluid to pass therethrough, the present invention covers the inner peripheral surface in an airtight state on the inner circumference of the leak inspection target position of the pipe. A strip-shaped annular sheet made of an elastic material, which is limited by a rigid body, is supplied with a pressure fluid between the annular sheet and the inner surface of the pipe, and the pressure fluctuation of the pressure fluid supply system is measured to detect leakage of the pipe. .

In the above, it is preferable to provide a pressurizing unit that presses both side edges of the annular sheet to the inner peripheral surface of the pipe to improve airtightness.

The annular core that restricts the inner circumferential surface of the annular sheet by rigidity is preferably configured by a plurality of fan-shaped core pieces divided into a plurality of circumferential directions, and the core sheets are placed in the piping. It is connected in a ring shape and is assembled along the inner peripheral surface of the above-mentioned annular sheet.

Preferably, the pressurizing unit includes an annular cushion body made of an elastic body that abuts against an inner peripheral surface of the peripheral edge portion of the annular sheet, and receives the buffer body to be pressed to a side edge portion of the annular sheet. a pressurizing ring that expands freely by supply of a pressurized fluid; and a pressurized pressure fluid supply unit that supplies a pressurized fluid to the pressurizing ring.

The pressurizing ring and the buffer body may be incorporated in a pocket formed on both side portions of the annular core.

According to the present invention, the inside of the pipe is made empty, and the inner peripheral surface of the pipe in which the annular sheet is predicted to have a leak along the joint portion of the pipe or the damaged portion caused by corrosion or the like is formed by the rigid ring. The core retains the shape of the inner peripheral surface of the annular sheet, and then pressurizes a pressure fluid between the annular sheet and the inner surface of the pipe, and detects a pressure fluctuation in the pressure fluid to detect a leak in the pipe. Since there is no need to inspect the entire piping by injecting the pressure fluid, it is only necessary to perform the inspection in order, and therefore, it is effective to perform the leak inspection with high efficiency.

When a pressurizing unit that closes both side edges of the annular seal to the inner circumferential surface of the pipe is provided, the airtightness of the test space formed between the annular seal and the pipe can be further improved, and the airtightness can be further improved. The inspection accuracy is further improved.

If the member that is in contact with the inner peripheral surface of the pipe is an elastic annular sheet, the inner surface of the pipe is not damaged or the like, and the pipe is damaged.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

1 is a cross-sectional view showing a pipe and an annular core portion to which the present invention is applied, and FIG. 2 is a cross-sectional view corresponding to AA of FIG. 1 in a state in which the present invention is applied to a leak inspection of a pipe joint portion, and FIG. An enlarged sectional view showing the main part.

The piping 1 to be applied has a capability for the operator to enter In the middle of the large diameter pipe (700 φ or more), the pipe joint portion 2 of the pipe 1 is similar to the pipe generally used in the prior art, and has a pipe end at the end of one pipe 1A which is externally fitted to the other pipe 1B. The fitting end portion 3 of the pipe end is fixed to the fitting connection position by the pipe end of the other pipe 1B abutting against the shoulder portion 3a of the inner end of the fitting connecting portion 3.

The inner circumferential surface of the pipe joint portion 2 of the pipe 1 is provided with a sealing material 4 so as to span the joint portions of the pipes 1A and 1B, and is closely adhered to the pipe 1A by retaining bands 5 and 5. The inner peripheral surface of 1B functions as a seal.

Next, a case where the fluid in the pipe joint portion 2 of the pipe 1 described above is inspected for leaks will be described as an example.

The leak detecting device of the present invention which performs the above-described inspection includes an annular sheet 6 which is provided along the inner peripheral surface of the pipe joint portion 2 of the pipe 1 as shown in FIG. 3 and is made of an elastic material; the annular core 7 The pressure-receiving unit 8 and 8 are attached to the annular core 7 and the both sides of the annular sheet 6 are disposed so as to restrict the inner circumferential surface of the annular sheet 6 by rigidity. The portions 6a and 6a are pressure-bonded to the inner circumferential surfaces of the tubes 1A and 1B, and the pressure fluid supply unit 10 including the pump 10a supplies the test space 9 formed between the annular sheet 6 and the inner peripheral surface of the pipe 1 for testing. The pressure fluid and the leak detecting unit 11 are located in a supply system that supplies the pressure fluid to the pressure fluid supply unit, and measure a change in the supply pressure to detect the leak.

The annular sheet 6 is made of a tough and elastic material such as rubber, synthetic rubber or soft synthetic resin, and has a width which is provided across the pipe joint portion 2 of the pipe 1, and two of the annular sheets 6 Side edge 6a and 6a are formed thick, and the jets 6b and 6b are formed so as to be in close contact with the inner peripheral surfaces of the pipes 1A and 1B at the both sides of the outer surfaces of the both side edges 6a and 6a.

The annular core 7 is formed by a collection of sector core pieces 7A, 7A, ... which are divided into a plurality of sections in the circumferential direction, and the sector core pieces 7A, 7A, ... are borrowed in the pipe 1. The ring-shaped core 7 is formed by being connected in a ring shape by bolts 12 or the like.

The sector-shaped core piece 7A includes a retaining surface 13 having a curved convex arc surface similar to the inner peripheral surface of the pipe 1, and is disposed at a central portion and left and right sides of the stop surface portion 13 in the width direction. Flanges 14, 14, 14 and flanges 15, 15 which are orthogonal to the width direction, and the stopper surface 13 is inserted to support a plug attached to the annular sheet 6. 16. The plug 16 is connected to the pipe of the pressure fluid supply unit 10 via the valve 17.

Pockets 18 and 18 are formed inside the flanges 14 and 14 on both sides in the width direction of the core piece 7A, and the pressurizing units 8 and 8 are provided in the pockets 18 and 18.

The pressurizing unit 8 includes an annular cushion body 19 made of an elastic material such as rubber that abuts against the back surface of the side edge portion 6a of the annular sheet 6, and is embedded in the cushion body to be pressed. A pressurizing ring 20 disposed in a pocket 18 on the back side of the 19, the pressurizing ring 20 being configured as a hollow tube and connected to a plug 21 mounted at the bottom of the pocket 18 through which the plug is inserted The plug 21 is inflated after receiving the supply of the pressure fluid from the pressurized pressure fluid supply system 22, and pressing the buffer body 19 to the opposite ring The side edge portion 6a of the sheet 6 is pressurized to be crimped to the inner surfaces of the tubes 1A, 1B. Further, 22a denotes a valve provided in the above supply system.

The pressure fluid supplied to the pressure ring 20 is shared with the pressure fluid supplied to the test space 9, or may be separately prepared.

Further, instead of the annular core 7, the strip-shaped piece may be formed by a buckle, and the ends of the strip-shaped piece may be stitched together to form a ring shape, and the buckle may be used to adjust the ring. The diameter is in close contact with the inner circumferential surface of the annular sheet 6.

Next, the action of the above embodiment will be described.

In order to inspect the leak from the pipe joint portion 2 of the pipe 1 to be inspected, an annular sheet 6 is added along the inner circumferential surface thereof so as to span the joint of the pipe joint portion 2 as shown in FIG. The stopper surface portion 13 of the core piece 7A of the annular core 7 is sequentially abutted against the back surface of the annular sheet 6, and the core sheets 7A, 7A, ... are fastened to each other by the bolts 12, thereby finally becoming a loop. shape.

At this time, the pressure ring 20 and the cushion body 19 are respectively provided in the pockets 18 and 18 of the annular core 7, and the buffer body 19 is located on the back surface of the left and right side edge portions 6a and 6a of the annular sheet 6. And set.

Then, the pressurized fluid is supplied to the pressurizing pressure fluid supply system 22 that supplies the pressurized fluid to the pressurizing ring 20, and the pressurizing ring 20 is expanded to press the back of the buffer body 19, and the buffer body 19, 19 is used to ring the ring. The both side edges 6a and 6a of the sheet 6 are pressed to the inner peripheral surfaces of the tubes 1A and 1B to be in an airtight state, whereby the inner surface and the ring of the tube 1 including the tube joint portion 2 are provided. The sheet 6 is formed so that the test space 9 spans the entire inner circumference of the pipe 1 It is airtight.

Thereby, the pressure fluid is supplied from the pressure fluid supply unit 10 into the test space 9 through the plug 16. At this time, if there is fluid leakage in the pipe joint portion 2, the pressure in the pressure fluid supply system fluctuates, so the leak detecting unit 11 detects the change and determines that fluid leakage has occurred, and turns to perform the pipe joint portion. 2 patching.

Even when the inspection target portion other than the pipe joint portion 2 is inspected, the annular sheet 6 and the annular core can be assembled on the inner surface of the pipe 1 where the leakage is predicted in the same order as described above. 7 to conduct a leak check.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

1‧‧‧Pipe

1A, 1B‧‧‧ tube

2‧‧‧ Pipe joints

3‧‧‧ fitting connection

3a‧‧‧Shoulder

4‧‧‧ Sealing material

5‧‧‧带

6‧‧‧Ring sheet

6a‧‧‧lateral edge

6b‧‧‧dike

7‧‧‧Ring core

7A‧‧‧core film

8‧‧‧ Pressurizing unit

9‧‧‧Test space

10‧‧‧Pressure fluid supply unit

10a‧‧‧ pump

11‧‧‧Leak detection unit

12‧‧‧ bolt

13‧‧‧stop face

14, 15‧‧‧Flange

16, 21‧‧‧ plugs

17, 22a‧‧‧ valve

18‧‧‧ pocket

19‧‧‧ Buffer

20‧‧‧ Pressurized ring

22‧‧‧Pressure pressure fluid supply system

Fig. 1 is a cross-sectional view showing an outline of a detecting device for carrying out a leak detecting method for a pipe according to the present invention.

Fig. 2 is a cross-sectional view corresponding to A-A of Fig. 1;

Fig. 3 is an enlarged cross-sectional view showing the main part of Fig. 1.

1‧‧‧Pipe

1A, 1B‧‧‧ tube

2‧‧‧ Pipe joints

3‧‧‧ fitting connection

3a‧‧‧Shoulder

4‧‧‧ Sealing material

6‧‧‧Ring sheet

6a‧‧‧lateral edge

7‧‧‧Ring core

8‧‧‧ Pressurizing unit

9‧‧‧Test space

10‧‧‧Pressure fluid supply unit

11‧‧‧Leak detection unit

Claims (8)

A leak detection method for a pipe, characterized in that, in a pipe having a pipe diameter accessible to an operator and internally for allowing a fluid to pass therethrough, an inner circumference of a leak inspection target position of the pipe is covered in an airtight state A strip-shaped annular sheet made of an elastic material whose circumference is limited by a rigid body, a pressure fluid is supplied between the annular sheet and the inner surface of the pipe, and the pressure fluctuation of the pressure fluid supply system is measured to detect the pipe. leakage. A leakage detecting device for a pipe, characterized in that: a pipe having a pipe diameter accessible to an operator and internally for allowing a fluid to pass includes: a strip-shaped annular sheet along which a leak is predicted to occur. The inner peripheral surface of the portion is disposed and made of an elastic material; the annular core is disposed over the entire circumference so as to restrict the inner peripheral surface of the annular sheet and has rigidity; and the pressurizing unit is attached to the annular core And pressing the both side edges of the annular sheet to the inner circumferential surface of the pipe; the pressure fluid supply unit supplies the pressure fluid to the test space formed between the annular sheet and the inner circumferential surface of the pipe; and the leak detecting unit The pressure fluid supply system is located and the pressure fluctuation is measured to detect the leakage of the piping. The leakage detecting device for piping according to the second aspect of the invention, wherein the annular core is formed by a plurality of fan-shaped core pieces divided into a plurality of circumferential directions, and the core pieces are used in a pipe. It is assembled so as to be connected in an annular shape and in close contact with the inner circumferential surface of the annular sheet. Leakage detection device for piping as described in item 2 of the patent application The pressurizing unit includes: an elastic annular buffer body that abuts against an inner peripheral surface of the peripheral edge portion of the annular sheet; and receives the supply of the pressure fluid that presses the buffer body to the annular sheet to expand freely a pressurizing ring; and a pressurized pressure fluid supply unit for supplying a pressurized fluid to the pressurizing ring. The leakage detecting device of the piping according to the third aspect of the invention, wherein the pressurizing unit includes: an elastic annular buffer body that abuts against an inner peripheral surface of the peripheral edge portion of the annular sheet; and the receiving buffer body a pressurizing ring that is swellable by pressing the supply of the pressure fluid to the annular sheet; and a pressurized pressure fluid supply unit for supplying a pressure fluid to the pressurizing ring. A leakage detecting device for a pipe according to the fourth aspect of the invention, wherein the pressure ring and the buffer body are housed in a pocket formed at both side portions of the annular core. The leakage detecting device for piping according to any one of the items of the present invention, wherein the annular sheet is formed in a shallowly concave shape, and the left and right side edges are thickened by the above The pressurizing unit is formed by pressing. The leakage detecting device of the piping according to the seventh aspect of the invention, wherein at least the outer peripheral surface of the thick-walled side edge portion is formed in a circumferential direction Two jetties are in close contact with the inner peripheral surface of the pipe to maintain the airtightness of the test space.