JP2016045009A - Inspection device and inspection method of piping - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection device and an inspection method of piping capable of performing a predetermined inspection without requiring much labor and cost for the inspection, having less generation of a human error, and additionally, capable of performing a prompt inspection regardless of the presence or absence of an obstacle on the upper part of a buried pipe.SOLUTION: An inspection device for inspecting the leakage position of a pipe includes: a travelling vehicle 18 for self-propelling inside of a pipe 12 by driving means 14; at least two self-expandable seal mechanisms 22, 22 mounted on the travelling vehicle 18 and realizing superior sealing characteristics on the outer peripheral surfaces by causing a gas to be introduced inside an expandable tube 20; pressure detection means 28 for detecting a pressure fluctuation of an inspection object space 26 closed by the two self-expandable seal mechanisms 22, 22; control means 32 for determining the presence or absence of the leakage from detection data detected by the pressure detection means 28; and position detection means 27 for detecting a position inside the pipe 12 of the inspection object space 26.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inspection apparatus and inspection method for piping that is preferably applied to inspection of piping buried in the ground, such as piping for supplying city gas.

  For example, inspections for city gas supply pipes can be broadly classified into two types: a leak inspection for detecting a gas leak location and a state inspection for investigating damage and corrosion of the pipe. As a leak test for detecting a gas leak point or the like, a boring method, a pressure drop method, or the like is known. In addition, as state inspection, there are known an inspection for measuring the thickness of the pipe by ultrasonic waves, a method for observing the inner surface of the pipe by a camera, and the like.

  With the boring method, for example, as shown in FIG. 3, boring is performed at a depth of about 50 cm and an interval of about 5 M on the line of the pipe 2 buried in the ground, and a pipe is set in the hole for about 1 minute. This is a method of inspecting for leakage by a gas detector or odor after a lapse of time or after suction.

  For example, as shown in FIG. 4, the pressure drop method is a method in which a jig 4 is inserted into the pipe 2, and a shielding space 6 is defined in the pipe 2 by the jig 4. This is a method of inspecting the airtightness in the pipe 2 by pressurizing the inside to the maximum working pressure and monitoring the pressure change in the shielded space 6 in this state (for example, Patent Document 1).

JP 2013-024730 A

  By the way, in the case of inspecting a leaked portion by the boring method as shown in FIG. 3, it is necessary to dig a hole at predetermined intervals while a person walks on the route of the pipe 2 for the inspection. However, there was a problem of spending much labor and cost. In addition, human error is likely to occur because boring is not performed correctly on the route or when surrounding gas such as exhaust gas is sucked.

  Furthermore, when there is an obstacle or the like above the pipe 2, there is a problem that the work associated with the inspection becomes extremely difficult. Further, even when there are no obstacles, the boring method of FIG. 3 has a problem that it is not possible to quickly specify because it is necessary to repeat the work until the leakage location is specified.

  On the other hand, in the case of the pressure drop method, since the piping is inspected directly from the ground surface, the risk of human error can be reduced and inspection is possible even when there is an obstacle above the piping 2 There is an advantage such as. However, since the position of the shielding space 6 is extended in order while extending the jig 4 from the end 8 that is the starting point of the pipe 2, it is not suitable for inspection of the pipe 2 over a long distance, and the location of the leak is specified. Still had the problem of requiring repeated work.

  In view of such circumstances, the present invention does not require a lot of labor and cost for inspection, is less likely to cause human error, and is not subject to predetermined inspection regardless of whether there is an obstacle above the buried pipe. In addition, an object of the present invention is to provide a pipe inspection apparatus and inspection method capable of performing quick detection.

In order to achieve the above object, a pipe inspection apparatus according to the present invention comprises:
An inspection device for inspecting a leaking part of piping,
A traveling vehicle that is self-propelled by driving means inside the pipe;
At least two self-expanding sealing mechanisms that are mounted on the traveling vehicle and exhibit sealing properties on the outer peripheral surface by introducing gas into the expandable tube;
Pressure detecting means for detecting pressure fluctuations in a space to be inspected sealed by the two self-expanding sealing mechanisms;
Control means for determining the presence or absence of leakage from the detection data detected by the pressure detection means;
Position detecting means for detecting a position of the inspection target space in the pipe;
It is characterized by having.

  The pipe inspection apparatus having such a configuration does not need to perform boring or the like for inspection, and the traveling vehicle automatically travels in the pipe and expands at least two self-expanding seal mechanisms at a position traveled a predetermined distance. By forming an inspection target space, it is possible to detect the presence or absence of leakage in the inspection target space by forming a test target space sealed by two self-expanding sealing mechanisms and measuring the pressure fluctuation in the subsequent inspection target space. it can.

  Then, from the analysis of the detection data, it is possible to detect at which position of the piping the leakage occurs.

In the present invention, it is preferable that at least the two self-expanding sealing mechanisms are connected by a common pipe, and a predetermined gas is simultaneously introduced or discharged through the common pipe.
With such a configuration, it is possible to easily control the introduction or degassing of gas into the two self-expanding sealing mechanisms, and the apparatus can be made compact.

Furthermore, in the present invention, it is preferable that the position detecting means is detected by measuring a moving distance of the traveling vehicle.
With such a configuration, it is possible to automatically identify the leaked portion, thereby eliminating human error.

Furthermore, in the pipe inspection apparatus according to the present invention, it is preferable that an operating member for manually adjusting the position is connected to the traveling vehicle.
With such a configuration, even when the self-propelled vehicle breaks down and it becomes difficult to self-propell in the piping, the traveling vehicle can be moved from the piping.

Moreover, the pipe inspection method according to the present invention includes:
Pressure fluctuation detection for detecting a pressure fluctuation with the passage of time in a space to be inspected by moving a pipe inspection apparatus provided with a pair of self-expandable seal mechanisms in the pipe, at the position. Process,
It has a position specifying step of specifying a leak location of the pipe from detection data obtained in the pressure fluctuation detecting step and position information in the pipe of the traveling vehicle.

  According to the pipe inspection method according to the present invention, it is possible to detect a leak location in the pipe and specify its position without performing boring or the like.

  According to the pipe inspection apparatus of the present invention, a traveling vehicle capable of self-running is accommodated in the pipe and traveled a predetermined distance, and then gas is introduced into at least a pair of self-expanding seal mechanisms at that position. By doing so, the pressure variation in the inspection space surrounded by the self-expanding mechanism is detected and the presence or absence of leakage is inspected from the detected data. Since the inspection can be performed from the inside of the pipe, and the inspection result can be quantified, the analysis of the inspection result can be easily systemized, and a human error can be prevented.

Further, by automating the leakage inspection, labor and time required for the inspection can be reduced, and furthermore, since the leakage location can be pinpointed, the leakage location can be quickly identified.
Furthermore, since a self-propelled traveling vehicle is used, a long-distance inspection can be performed.

FIG. 1 is a schematic view showing an example of an inspection apparatus employed for carrying out a piping inspection method according to the present invention. FIG. 2 is a schematic cross-sectional view showing a state before and after sealing of the self-expanding seal mechanism employed in the inspection apparatus of FIG. FIG. 3 is a schematic diagram showing a piping inspection method by a conventional boring method. FIG. 4 is a schematic diagram of a conventional pipe inspection apparatus disclosed in Japanese Patent Laid-Open No. 2013-24730.

  Hereinafter, an inspection apparatus and inspection method for piping according to the present invention will be described with reference to the drawings.

  FIG. 1 schematically shows a state in which an inspection apparatus 10 suitable for carrying out a pipe inspection method according to a preferred embodiment of the present invention is accommodated in a city gas supply pipe 12 buried in the ground. It is a longitudinal cross-sectional view.

  The inspection device 10 uses, for example, a traveling vehicle 18 that is capable of self-propelling in the pipe 12 when the wheels 16 are rotated by driving means 14 such as a motor. The distance between the front and rear wheels 16, 16 provided on the carriage of the traveling vehicle 18 is constant. The traveling vehicle 18 is equipped with a self-expanding seal mechanism 22 that exhibits a sealing function on the outer peripheral surface by introducing an appropriate fluid such as compressed air or nitrogen gas into the annular tube 20. , Pressure detection for detecting pressure fluctuations in the test object space 26 formed between the pump 24 for introducing compressed air into the tube 20 of the self-expandable seal mechanism 22 and the two self-expandable seal mechanisms 22, 22. Detected by means 28, battery power supply 30, position detection means 27 for introducing and discharging gas to the tube 20, attitude control of the traveling vehicle 18, position detection of the inspection object space 26, and pressure detection means 28. Control means 32 for identifying the presence or absence of leakage in the inspection target space 26 from the detected data is mounted.

  The separation distance A between the tubes 20 and 20 of the pair of self-expanding seal mechanisms 22 and 22 is set to a predetermined length.

  As a sealing material employed in the self-expanding sealing mechanism 22, various products are provided on the market under the name of Infrat Seal (registered trademark) by Nippon Valqua Industries, Ltd., and are gaining popularity.

  The sealing performance of such a self-expanding sealing mechanism 22 depends on the transmission of the supply pressure to the sealing surface. For example, as shown in FIG. 2, when the pressure supply to the tube 20 is zero, The one in the solid line posture expands greatly to the outside like a two-dot chain line due to an increase in supply pressure, thereby causing the outer peripheral surface to exhibit a sealing function.

The traveling vehicle 18 of the present embodiment is provided with at least two self-expanding sealing mechanisms 22 as described above in one carriage. Further, if these self-expanding seal mechanisms 22 and 22 are connected by a common pipe 34, gas introduction or gas discharge into the tubes 20 and 20 can be performed simultaneously between the two self-expanding seal mechanisms 22 and 22. It can be carried out.
As the gas introduced into the tube 20, compressed air, nitrogen gas, or the like can be employed.

  In the inspection apparatus 10 configured as described above, if the circumferential length of the wheel 16 is L and the rotational speed of the wheel 16 is T, the distance traveled by one rotation of the wheel 16 is L × T. Therefore, the travel distance from the starting point (origin position) of the traveling vehicle 18 can be known by setting the rotation speed T of the wheel 16 that rotates in one traveling of the traveling vehicle 18. That is, it is possible to identify position information indicating how far the inspection target space 26 is from the starting point where the inspection is started.

Therefore, in such an inspection apparatus 10, by rotating the wheel 16 a predetermined number of times in each inspection, the position of the inspection object space 26 can be extended in order of, for example, A, 2A, 3A. it can. As a result, if the self-expanding seal mechanisms 22 and 22 are activated at each position, the subsequent pressure fluctuation is detected, and the detection result is stored in the control means 32, the detection data stored in the control means 32 is recorded. It is possible to determine at which position the leakage has occurred or whether the leakage has not occurred.
Hereinafter, a pipe inspection method using such an inspection apparatus 10 will be described in more detail.

  First, when the pipe to be inspected is an embedded pipe 12 for supplying city gas, a part of the pipe 12 is exposed by digging a hole, and at least inside the pipe 12 in the section to be inspected by appropriate means therefrom. City gas is degassed. And the inspection apparatus 10 is accommodated in the piping 12 in the state in which city gas was deaerated and safety was confirmed. This operation is manually performed by an operator or the like.

  Then, after it is confirmed that the inspection apparatus 10 is arranged in an appropriate posture, a first leakage inspection is performed by a command signal from the control means 32. In that case, first, the pump 24 is driven by the battery power source 30, and appropriate gas is introduced into the tubes 20, 20 of the self-expanding seal mechanisms 22, 22 by driving the pump 24. Thereby, a sealing function is exhibited on the outer peripheral surfaces of the pair of tubes 20 and 20 of the pair of self-expanding sealing mechanisms 22 and 22.

  Thereby, the space 26 to be inspected is defined in a sealed state between the two self-expanding seal mechanisms 22 and 22. At this time, since the two self-expanding sealing mechanisms 22 and 22 are connected via the common pipe 34, introduction of nitrogen gas or the like can be performed simultaneously from one pressure source (pump 24). Inspection time can be shortened.

  In this way, after the self-expanding sealing mechanism 22 exhibits the sealing function, the pressure variation with the passage of time in the inspection object space 26 is detected by the pressure detecting means 28. The detection result of the pressure fluctuation with the passage of time is stored in the control means 32 together with the position information of the inspection target space 26 in the pipe 12.

  After a predetermined time has elapsed, the gas introduced into the inside of the tube 20 of the self-expanding seal mechanism 22 is discharged by a command signal from the control means 32. As a result, the traveling vehicle 18 can travel again. Thereafter, the traveling vehicle 18 is traveled by a preset distance A. Thereby, the inspection apparatus 10 moves to the next inspection position. The second inspection is a position immediately next to the position A in FIG. Assuming that the first inspection position is A and the second inspection range is 2A, in the present invention, it is possible to sequentially inspect A, 2A, 3A. It becomes. The detected data is stored in the control means 32. The inspection method of this embodiment is automatically performed while extending the inspection target position as described above.

  In the inspection method of this embodiment, for example, when the total length of the pipe 12 is 10 meters and the distance A is set to 2 meters based on the number of rotations of the wheels 16, an inspection of 10 ÷ 2 = 5 (times) is performed. By carrying out, it is possible to inspect the entire range of 10 meters to be inspected. Then, it is analyzed from the stored detection data whether there was a pressure fluctuation that can be determined as a leak in the inspection performed at the time.

As described above, according to the pipe inspection method of the present invention, the pressure fluctuation detecting step for detecting the pressure fluctuation with the passage of time of the inspection target space 26 surrounded by the pair of self-expanding seal mechanisms 22, 22, By having a position specifying step for specifying the leaked portion of the pipe 12 from the detection data obtained in the fluctuation detecting step, it is possible to shorten the time required for human labor and analysis required in the conventional inspection method it can. Moreover, since it can be automated, it is possible to prevent the occurrence of human error.
As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to the said embodiment at all.

  For example, in the above-described embodiment, only the leakage inspection of the pipe 12 is performed. Instead, for example, a camera that automatically shoots the traveling vehicle 18 to grasp the internal state of the pipe visually. It can also be installed. If the camera is photographed in synchronism with the activation of the self-expanding seal mechanism 22, the photographing position in the pipe 12 can be specified.

  Furthermore, a thickness measuring device using ultrasonic waves can be mounted on the traveling vehicle 18. The measurement of the thickness of the pipe 12 can also be specified by synchronizing with the activation of the self-expanding seal mechanism 22 as in the case of the camera.

  Moreover, in the said embodiment, when the drive means 14 of the traveling vehicle 18 breaks down, there is a possibility that the traveling vehicle 18 may be left in the pipe 12. The traveling vehicle 18 can be forcibly pulled out from the pipe 12 by connecting the string-like member 36 to the rear end side and manually pulling the string-like member 36 when necessary.

  Further, in the above-described embodiment, an example in which two self-expanding seal mechanisms 22 are mounted has been described. However, three or four self-expanding seal mechanisms 22 can be mounted. With this setting, two or three inspection target spaces 26 can be set with the traveling vehicle 18 stopped at one place, and the inspection of the inspection target spaces 26 can be performed simultaneously. Become.

  In the above embodiment, an example in which the inspection target space 26 formed between the two self-expanding seal mechanisms 22 and 22 connected by the common pipe 34 is constant has been described. Inflatable seal mechanisms may be mounted on different traveling vehicles 18 so that the inspection target space 26 can be set freely.

  Furthermore, when inspecting the city gas supply pipe 12 or the like, it is preferable that each element necessary for the inspection has an explosion-proof structure. The traveling vehicle 18 can be traveled wirelessly from the outside, or can be steered from the outside by wire.

In the above embodiment, the buried pipe 12 is inspected. However, the pipe 12 may of course not be buried, and may be a pipe installed on a plant, a ship, the seabed, or the like. Further, the fluid to be transported is not limited to city gas or the like, and may be, for example, gasoline, a chemical substance, general industrial gas, or the like, and can be applied to inspection of various pipes regardless of the installation location or the applied fluid.
As described above, the inspection apparatus and the inspection method according to the present invention can be variously modified based on the technical idea of the present invention.

6 Shielding space 8 End 10 Inspection device 12 Pipe 14 Driving means 16 Wheel 18 Traveling vehicle 20 Tube 22 Self-expandable seal mechanism 24 Pump 26 Inspection object space 27 Position detection means 28 Pressure detection means 30 Battery power supply 32 Control means 34 Common piping 36 String-shaped member A Separation distance

Claims (5)

An inspection device for inspecting a leaking part of piping,
A traveling vehicle that is self-propelled by driving means inside the pipe;
At least two self-expanding sealing mechanisms that are mounted on the traveling vehicle and exhibit sealing properties on the outer peripheral surface by introducing gas into the expandable tube;
Pressure detecting means for detecting pressure fluctuations in a space to be inspected sealed by the two self-expanding sealing mechanisms;
Control means for determining the presence or absence of leakage from the detection data detected by the pressure detection means;
Position detecting means for detecting a position of the inspection target space in the pipe;
A pipe inspection apparatus characterized by comprising:   The pipe inspection apparatus according to claim 1, wherein at least the two self-expanding seal mechanisms are connected by a common pipe, and a predetermined gas is simultaneously introduced or discharged through the common pipe.   The pipe inspection apparatus according to claim 1, wherein the position detection unit is detected by measuring a moving distance of the traveling vehicle.   The piping inspection apparatus according to claim 1, wherein an operating member for manually adjusting the position is connected to the traveling vehicle. Pressure fluctuation detection for detecting a pressure fluctuation with the passage of time in a space to be inspected by moving a pipe inspection apparatus provided with a pair of self-expandable seal mechanisms in the pipe, at the position. Process,
And a position specifying step of specifying a leak location from the detection data obtained in the pressure fluctuation detecting step.

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