JPS63120237A - Method for inspecting leakage of piping - Google Patents

Abstract

PURPOSE:To facilitate work and to enhance working efficiency, by a method wherein an expansible hollow tight stopper is inserted in piping to be moved to an arbitrary position by pressure difference and subsequently expanded to closely contacted with the inner wall of the piping to perform inspection. CONSTITUTION:A rubber ball 12 being a hollow tight stopper is inserted in piping 11 from the inlet end part thereof and a closure member 19 is hermetically mounted to the inlet end part of the piping 11. Subsequently, when a valve 21 is opened to inject compressed air in the piping 11, the rubber ball 12 moves in the direction shown by an arrow (a). When the ball 12 reaches a predetermined position, the valve 21 is closed to stop the movement of the ball 12 and, at the same time, compressed air is injected in the rubber ball 12 through a hose 13 and the ball 12 is expanded to be closely contacted with the inner wall surface of the piping 11. Then, the valve 21 is opened to inject compressed air for inspecting leakage in the space between the ball 12 and the closure member 19 of the piping 11 to set said space to predetermined pressure and, in this state, the presence of the change in pressure is inspected by a pressure gauge 22.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for detecting whether or not piping is airtight and detecting leakage points.

(Prior Art) Generally, leakage tests are performed on both newly installed piping and existing piping. Conventionally, for this type of inspection, a method is known in which a predetermined section of the pipe is sealed, a pressurized fluid at a predetermined pressure is injected into the sealed section, and the presence or absence of airtightness is tested based on changes in the pressure. As an example of the jig used for this inspection, the one shown in Figure 3 has been proposed6 (Japanese Unexamined Patent Publication No. 59
(Refer to Publication No.-230135). As shown in FIG. 3, in this jig, a pressure bag 2 inserted into a pipe 1 is attached to a moving spring-type wire 3 using a tightening band 4 so that the mounting position can be changed. One end of the inserted pressurizing hose 5 is connected to the pressure bag 2, and the other end of the hose 5 is guided to a pressure source through a pipe 7 penetrating the end sealing pressure bag 6 of the piping 1. Also, both pressure bags 2 and 6
Pressurized fluid is also injected into the piping 1 and the pressure bag 6, which are partitioned by . Therefore, by detecting changes in the pressure within the pipe 1 divided by the pressure bags 2 and 6 using a pressure gauge or the like, it is possible to test whether the pipe 1 is airtight. If an abnormality is found as a result of the inspection, the jig is taken out from inside the pipe 1, the tightening position of the pressure bag 2 is moved, the jig is inserted into the pipe 1 again, and the above operation is repeated. .

(Problems to be solved by the invention 1.) When performing an airtight inspection of piping using the conventional bureau shell,
Every time the pressure bag 2 in the pipe 1 is moved, the entire jig must be taken out from the pipe 1, which is a complicated process that requires a considerable amount of time and effort, and is extremely inefficient.
In addition, when using the above-mentioned jig for piping that is bent at right angles, such as gas piping, there is a problem with the flexible flexibility of the spring type wire 3, and in places where there is a step in the piping joint, the wire 3 There are problems such as not only cannot be inserted smoothly, but also it is impossible to insert.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned conventional problems, and is characterized by the fact that the fluid is injected and discharged into the piping through a hose or the like. An inflatable hollow seal is inserted into the pipe, the end of the pipe is sealed so that the hose etc. can move freely, and a pressurized fluid is injected between the hollow seal and the sealed end of the pipe. Reduce the pressure between the seal plug and the other end of the piping, move the hollow seal together with a bow, etc. to an arbitrary position δ, and inject pressurized fluid into the hollow seal via a hose or the like to expand the hollow seal. After it is in close contact with the inner wall of the piping, the pressure between the hollow seal plug and the sealed end of the piping is increased or decreased to a specified pressure, and the change in pressure is detected to detect the presence or absence of airtightness of the piping and the location of leakage. be.

(Function) According to the present invention, first, a hollow seal plug is inserted into the pipe from one end, the pipe end is sealed, and pressurized fluid is injected between the pipe end and the hollow seal plug, or When the pressure between the seal plug and the other end of the pipe is reduced, the hollow seal moves within the pipe toward the other end, and at this time, the hose, etc. is drawn into the pipe together with the hollow seal. When the hollow seal reaches a predetermined position within the piping, injection of pressurized fluid or pressure reduction is stopped, and the hollow seal is stopped. Next, a pressurized fluid is injected into the hollow seal to expand the hollow seal and make it tightly adhere and fix to the inner surface of the pipe. The position of the hollow seal plug at this time can be easily known by marking the dimensions on the hose or the like. In this sealed state, pressurized fluid at a predetermined pressure is injected into the sealed section in the piping or the pressure is reduced to a predetermined pressure, and changes in the pressure within the sealed section are detected by a pressure gauge. If there is no change in pressure, there is no leakage in the piping, and if there is a change in pressure, there is a leakage in the piping. Therefore, when the pressurized fluid inside the hollow seal is discharged,
Since the hollow seal plug moves inside the pipe, the above-described operation can be repeated and inspected to check for airtightness and the location of leakage.

(Embodiment) In FIG. 1, which describes an embodiment of the present invention in detail based on the drawings, 11 is a pipe, 12 is a rubber ball that is a hollow seal, and 13 is a hose, one end of which is connected to the rubber ball 12 in an airtight manner. A vibe 15 is connected to the compressed air tank 14 at the other end.
and are connected via valve 16. rubber ball 1
The outer diameter of No. 2 is when compressed air is not injected.
It is made slightly smaller than the inner diameter of the pipe 11 to allow smooth movement within the pipe 11. ,1
Reference numeral 7 indicates a pressure gauge connected to the vibrator 15, and reference numeral 18 indicates an exhaust valve, which is provided to exhaust air within the rubber ball 12 and release the rubber ball 12 from its close contact with the inner surface of the pipe 11. Reference numeral 19 denotes a closing member for sealing the inlet end of the pipe 11, through which a hose 13 is slidably and airtightly passed through the center of the end surface, and a compressor for leak testing pressurized fluid is used. One end of the air injection vibrator 20 is connected. The other end of this vibe 20 is connected to the compressed air tank 14,
A valve 21 is provided in the middle. The closing member 19 is provided with a pressure gauge 22 for detecting pressure changes within the pipe 11 and an exhaust valve 23. In addition,
The outer surface of the hose 13 is marked with a scale and numbers indicating the length from the rubber ball 12 side, so that the position of the rubber ball 12 from the inlet end of the pipe 11 can be measured. There is.

Further, the hose 13 can be easily wound up and unwound if it is wound around the feeder 5 and the hose reel 24 shown in FIG.

The closing part ((19 is as shown in FIG. 2,
It consists of a vibrator 25, a circular end plate 26 that closes one end of the vibrator, and a connecting nut l-271 that is loosely fitted around the other end.
The two are connected in an airtight manner by a connecting nut 1-27 with a connecting pin 8 interposed therebetween. Note that 29 is a hose through hole formed in the circular end plate 26, and a seal ring 30 is attached to the hose through hole.

According to an embodiment of the present invention, each valve 16.
21. After closing 23 and opening the exhaust valve 18, insert the rubber ball 12 from the inlet end of the pipe 11 as shown in FIG.
is attached to the inlet end of the pipe 11 in an airtight manner.

Next, when the valve 21 is opened and compressed air is injected into the pipe 11, the rubber ball 12 moves in the direction shown by arrow A in FIG. This rubber ball 12 is placed at a predetermined position (first
When reaching the position indicated by the two-dot chain line 12a in the figure, the valve 21 is closed to stop the movement of the rubber ball 12, and at the same time, the exhaust valve 18 is closed and the valve 16 is opened to compress the air through the vibrator 15 and hose 13. Air rubber ball 12
Inject inside. As shown by the two-dot chain line in FIG. 2, the rubber ball 12 expands and comes into close contact with the inner wall surface of the pipe 11, so that the pressure inside the rubber ball 12 is twice the predetermined pressure (detected by the pressure gauge 17). When this happens, valve 16 is closed. In this way, the sealing of the leakage test section is taken care of, valve 21
is opened and compressed air is injected into the leak test section of the piping, and when the pressure reaches a predetermined pressure (detected by pressure gauge 22),
Close valve 21. Observe the pressure gauge 22 in this state,
Inspect for pressure changes. After a predetermined time, if there is no change in pressure, there is no leakage in the piping 11, but if a change in pressure, that is, an abnormality is observed, the exhaust valve 18.23 is opened to exhaust the air inside the rubber ball 12 and the piping 11. . Therefore, while reducing the pressure in the inspection section of the piping 11, the hose 13 is pulled out 7 to move the rubber ball 12 to the inlet end, and then the valve 16 is opened again to remove the rubber ball 12.
Compressed air is injected into the tube to bring the rubber ball 12 into close contact with the inner surface of the pipe 11, and the above operation is repeated to find the leakage point. Further, if there is no pressure change after moving due to an abnormality, it can be seen that there is a leakage point in the moved section. In addition, when moving the rubber ball 12 to the inlet end, the other end of the pipe 11 may be sealed and compressed air may be injected between this and the rubber ball 12, or the hose 13 may be pulled out. .

Although embodiments of the invention use air as the pressurized fluid, other gases or liquids such as water may be used.

In the embodiment of the present invention, since the hose 13 is provided with a length scale, the distance from the inlet end of the leakage point of the pipe 11 can be accurately measured.

It should be noted that the present invention is not limited to the embodiments described in "2" above, and inspection can be carried out efficiently by appropriately combining pressurization and depressurization. Furthermore, as for the sealing means at the inlet end, it goes without saying that a hollow sealing plug such as a rubber ball may be used. In general, a device for detecting the amount of movement of the hose 13 can be attached to the sealing member 19, so that the dimensional scale of the hose 13 can be omitted.

(Effects of the Invention) As described above, the present invention inserts an expandable hollow seal plug into which pressurized fluid is injected and discharged by a hose or the like in a pipe, and moves this hollow seal plug by pressurizing or depressurizing the pipe. As a result, the movement of the hollow seal is extremely smooth, and it can be easily moved even in areas where the piping is bent at right angles or where there is a step in the piping joint, making it possible to perform leakage inspections on all types of piping, as well as to easily move hoses. By detecting the amount of movement, the location of the leak can be reliably determined. Furthermore, the present invention is not limited to the above-mentioned effects, but can also be used for removing clogged pipes, cleaning inside pipes, and installing electrical pipes, and can be applied to all fields.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram 5 of an embodiment of the present invention, Fig. 2 is a diagram showing an example of a sealing means for the artificial end of a pipe, and Fig. 3 is a diagram showing a conventional sealing means for leak testing. It is a partially cutaway schematic side view showing the components. 11-Piping, 12-Rubber ball (hollow seal plug), 13-
Hose, 14--Compressed air tank, 19--Closing member at piping inlet end, 22--Pressure gauge.

Claims (1)

[Claims] (1) Insert an expandable hollow seal plug into which pressurized fluid is injected and discharged using a hose, etc. into the pipe, seal the end of the pipe so that the hose, etc. can move freely, and connect the hollow seal plug to the pipe. Inject pressurized fluid between the hollow seal and the other end of the piping, or reduce the pressure between the hollow seal and the other end of the piping, move the hollow seal together with the hose, etc. to an arbitrary position, and insert the hose, etc. into the hollow seal. After injecting pressurized fluid through the pipe and inflating the hollow seal plug so that it comes into close contact with the inner wall of the pipe, the pressure between the hollow seal plug and the sealed end of the pipe is increased or decreased to a predetermined pressure, and changes in the pressure are detected. A leakage inspection method for piping, characterized by detecting the presence or absence of airtightness of piping and the location of leakage.