JPH0225078B2 - - Google Patents

Description

[Detailed description of the invention] Industrial applications The present invention relates to an emergency shutoff device for gas mains.

Conventional technology When air leaks occur in a city gas main pipe (low pressure pipe) buried underground, for example, when a valve installed in the gas main pipe is closed, the city gas supply is interrupted from the main pipe between the valves. The customer receiving the gas will be cut off, causing inconvenience to a large number of customers (usually estimated at several thousand to tens of thousands of customers). It is desirable to urgently shut down the The applicant previously proposed an emergency shutoff method, which involves inserting and inflating an air bag into the gas main pipe using a supply light pipe extending from the city gas main pipe buried underground to the consumer. and its device (for example, Japanese Patent Application Laid-Open No. 1989-1999)
(See Publication No. 17091). According to this emergency shutoff method and its device, since the supply light bulb is used, emergency shutoff can be performed at the part closest to the leakage point, and there is no inconvenience to anyone other than the nearest customer. It does not require any work such as digging the ground or drilling the main pipe, so it can be shut off in an emergency. However, the supply light bulb usually has a small diameter of about 20 to 60 mm in diameter, and it often includes a bent part consisting of an elbow (or bend) in the middle, and there may be as many as 5 to 10 bent parts. This caused trouble in the work with regular wire passing machines.

Problems to be Solved by the Invention The present invention has been made for the purpose of solving the above-mentioned conventional problems.

Means for Solving the Problems The present invention provides a method for connecting both ends of a hollow flexible wire inserted into a gas main pipe through a supply light pipe branched from a gas main pipe using a wire threading machine. Furthermore, a guide ball disposed in at least one place in the middle part and a hollow tip guide consisting of a coil spring that sequentially connects the guide balls are attached so that both hollow parts are connected, and a gas is injected into the hollow part of the tip guide. An inflatable and deflated bag for shutting off the main line is stored so that it can be protruded outside when necessary, and a supply hose is inserted into the hollow part of the flexible wire to supply pressurized fluid appropriately into the bag. This invention relates to an emergency shutoff device for gas mains, which is characterized by:

Embodiments Examples of the present invention will be described below based on the accompanying drawings.

In the figure, 1 is a wire threading machine equipped with a hollow flexible wire 11 as a wire threading material, and as such wire threading machine 1, there are various types of well-known types used for cleaning various types of piping. Can be used.

As wire passing machine 1, the manual type is shown in Figure 1, and the second type is shown in Figure 1.
The figure shows an automatic type, and by operating the handle 12,
By applying rotation to the rotating container 14 supported by the frame 13, the flexible wire 11 is housed in a wound state inside the rotating container 14.
rotation in a direction around the central axis (hereinafter referred to as torsional rotation). wire 1
1, the automatic type shown in FIG. 2 is equipped with a feed roll 16 that is actively rotated by a motor 15. The flexible wire 11 provided in the wire passing machine 1 needs to be hollow, and for example, a so-called snake wire composed of one or more layers of coil springs may be used.

At the tip of the flexible wire 11 of the wire threading machine 1, a hollow tip guide 2 is attached to both hollow parts 26 and 11.
1 (see FIG. 3) are provided in communication with each other.

As shown in detail in FIG. 3, the tip guide 2 includes guide balls 21 and 22 arranged at both ends and a guide ball 23 arranged at at least one place in the middle. The holes 2 are arranged in the direction of the central axis so as to form a part of the hollow part 26.
11, 221 and 231 are hollowed out. It is necessary that the outer diameter of the guide balls 21 to 23 is slightly smaller than the inner diameter of the small-diameter pipe, for example, the gas supply light tube a, and the guide balls 21 to 23 are usually smaller in diameter by about 1 to 8 mm (diameter). In particular, the guide ball 22 connected to the wire 11 may be smaller by about 1 to 3 mm.

The guide balls 21 to 23 have their holes 211 and 22
1 and 231 are sequentially connected by coil springs 24 and 25 so that they communicate in the axial direction.

FIG. 4 shows the state of the tip guide 2 passing through the bent portion b of the supply lamp tube a. Among the guide balls 21 to 23 of the tip guide 2, the most advanced guide ball 21 moves through the bend b while easily overcoming the unevenness in the bend b due to its spherical surface.
Therefore, the coil springs 24 and 25 following this
moves through the bending part b while being guided by the guide ball 21 while bending along the bending part b, and at this time, the intermediate and proximal guide balls 23 and 22 center the coil springs 24 and 25. .

For example, if the intermediate guide ball 23 is omitted, the coil spring 241 between the guide balls 21 and 22 will meander within the bend b, as shown in FIG. 5, which will not only increase the resistance inside the pipe but also reduce the pushing force. I will do it.

Furthermore, if the guide ball 22 at the proximal end is omitted, the guide balls 21 and 23 are too close together as shown in FIG.
The flexible wire 11 is bent and gets stuck in the bent portion b, and the pushing force is not sufficiently transmitted to the distal end.

In the present invention, since the tip guide 2 is provided with guide balls 21 to 23 at both ends and the intermediate portion, the fourth
As shown in the figure, the coil springs 24 and 25 are smoothly bent and centered along the bending part b, and the pushing force from the flexible wire 11 can be efficiently transmitted to the leading guide ball 21. As for the length of the tip guide 2, as shown in FIG. This is most advantageous in obtaining smooth bending and centering properties, but there is no particular problem with the length.

When passing through the bending part b of the distal end guide 2, it is necessary to rotate the flexible wire 11 in the direction around the axis and cause the leading end guide ball 21 to take a swinging motion.

In the present invention, in order to efficiently transmit the rotational force of the wire 11 to the most advanced guide ball 21, the wire 1 is used as the coil springs 24 and 25.
It is advantageous to use a spring with a slightly weaker spring than 1. Normally, the coil springs 24 and 25 are 0.8
It is preferable that a spring of about 0.4 to 0.4 is used, and that the spring properties are gradually lowered toward the tip.

The tip guide 2 is operated by coil springs 24 and 25 that connect the guide balls 21 to 23 and the like.
As a whole, it can exhibit an extremely excellent guiding function, and can sufficiently achieve the purpose of passing through a small diameter pipe, for example, with a diameter of 20 to 60 mm and having about 5 to 10 bends in the middle.

In the hollow part 26 of the tip guide 2, an inflatable and deflated bag 3 made of rubber, for example, for shutting off the gas main pipe is stored so as to be able to protrude to the outside when necessary. 1
A supply hose 4 for appropriately supplying pressurized fluid into the bag 3 is inserted into the bag 11 .

FIG. 3 shows an inverted bag 3. In this type, the bag 3 is stored in a guide tube 31 in an inverted state, and pressurized fluid is supplied from a supply hose 4 into the guide tube 31. The structure is such that the bag 3 can be made to protrude to the outside by supplying the same amount of water.

FIG. 3-a shows a push-out bag 3,
As shown in FIGS. 7 and 8, the base end 42 of the supply hose 4 reinforced with the piano wire 41 inserted therein is made to protrude outward from the rotating container 14 of the wire threading machine 1. By pushing in the proximal protrusion 42 appropriately, the bag 3 attached to the distal end of the hose 4 can be pushed out of the distal end guide 2. In FIGS. 7 and 8, reference numeral 5 denotes a grip part provided on the protruding part 42 of the supply hose 4;
One of the hollow parts 51 is connected to the supply hose 4, and the other is provided with a hose joint 52. The apparatus of the present invention shown in FIGS. 1 and 2 is of an inverted type, and a supply port 17 is formed in the rotating container 14 for supplying pressurized fluid to the supply hose 4.

An induction ball 2 is attached to the tip of the tip guide 2 via a coil spring 27 whose springiness is even weaker than the coil springs 24 and 25, as shown in Fig. 3-b.
8. The guide ball 28 is made of lead, for example, and serves to constantly guide the tip guide 2 downward. When such a guide ball 28 is provided, a bellows portion 8 is attached to the guide tube 31.
11 is preferably formed in advance to impart elasticity.

When the gas main pipe d is urgently shut off using the device of the present invention, the gas supply light pipe a is cut off as shown in Fig. 9.
is removed at the gas tank to form a working port _A1 , connect the U-shaped pipe C to this working port _A1 , and seal the gas with water. Other suitable means can be used for gas blockage.

Next, as shown in FIG. 10, the wire passing machine 1 is operated to insert the flexible wire 11 from the U-shaped tube c into the outer tube a under the guidance of the tip guide 2. The togai tube a has a diameter of 20 to 60 mmφ and often includes about 5 to 10 bends b in the middle, but in the present invention, the tip guide 2 guides the flexible wire inside the togai tube a. 11 can be inserted without any problem.

After the tip guide 2 reaches the gas main pipe d by inserting the flexible wire 11, the inverted type is connected from the supply hose 4 to the guide tube 3.
By supplying pressurized fluid into the inside of the tip guide 2, or by pushing the protrusion 42 of the supply hose 4 into the flexible wire 11 in the case of the extrusion type, the bag 3 is made to protrude from the inside of the tip guide 2 to the outside. By supplying and expanding pressurized fluid, for example compressed air, into the bag 3 through the supply hose 4, the purpose of shutting off the gas main d, as shown in FIG. 11, can be achieved.

After the leakage point has been repaired and there is no longer a need to shut off the gas, the pressurized fluid is released through the supply hose 4, the bag 3 is deflated, and the wire passing machine 1 is operated. The current state can be restored by pulling out the flexible wire 11 and the bag 3 outside the tube, then removing the U-shaped tube c, and reconnecting the working port _A1 of the outboard tube A to the gas tank. .

Effects In the present invention, since the wire passing machine is equipped with a tip guide that can sufficiently pass through the gas supply light outer tube having about 5 to 10 bends, it is possible to The purpose of shutting off can be achieved easily, quickly and reliably by using such a gas supply light pipe, and since the light pipe is used, emergency shutoff can be performed at the location closest to the leakage point. There will be no inconvenience to anyone other than the nearest customer.

[Brief explanation of drawings]

Fig. 1 is a partial vertical sectional view showing an example of the manual implementation of the present invention, Fig. 2 is a longitudinal sectional view showing an example of the automatic implementation of the invention, and Fig. 3 is an enlarged sectional view of the tip guide. 3-a and 3-b are enlarged sectional views showing modified examples of the tip guide, FIGS. 4 to 6 are explanatory views of the guiding principle of the tip guide, and FIG. 7 is a partial enlarged sectional view of the supply hose protrusion. FIG. 8 is a partially enlarged cross-sectional view of the gripping portion, and FIGS. 9 to 11 are partial longitudinal cross-sectional views showing the state of the gas main emergency shutoff operation by the apparatus of the present invention in the order of work steps. In the figure, 1 is a wire threading machine, 11 is a flexible wire, 2 is a tip guide, 21 to 23 are guide balls,
24 and 25 are coil springs, 3 is a bag, and 4 is a supply hose.

Claims (1)

[Claims] 1 At the tip of a hollow flexible wire that is inserted into the gas main through a supply light pipe branched from the gas main using a wire passing machine, it is placed at both ends and at least one point in the middle. A hollow tip guide consisting of a guide ball and a coil spring that sequentially connects the guide balls is attached by connecting both hollow parts, and an inflatable and deflated bag for shutting off the gas main pipe is installed in the hollow part of the tip guide. an emergency gas main pipe, characterized in that a supply hose is inserted into the hollow part of the flexible wire to supply pressurized fluid as appropriate into the bag, while the bag is stored so as to be able to protrude to the outside when necessary. Shutoff device.