JP2002195483A - Joint for purge, method of executing the same, and method of purge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts and improve efficiency in executing piping work of gas pipes, compared with a conventional method in which a joint for connecting pipes and that for air purge are separately mounted, by purging air remaining in pipes with a pipe connecting joint when the gas pipes are finally connected. SOLUTION: The peripheral surface of a spigot of an electrofusion cheese joint is threaded and a peripheral groove is formed, and an O-ring is set in the groove. Then a cap 15 is screwed and a joint 11 for purge can be sealed. Each end of pipes 16a and 16b connected by the joint 11 for purge is squeezed off by a squeeze-off tool 17, and after that, the end of the pipes is inserted into the joint 11 for purge and electrofused. Next, the squeeze-off tool 17 is detached with the cap 15 being taken off, and the air purge is executed. After the air purge, the cap 15 is attached again and the joint for purge is sealed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for purging which is used when connecting pipes in a pipe connection using resin pipes, for example, when connecting gas pipes, or when replacing defective pipes. And its construction method and purging method.

[0002]

2. Description of the Related Art Taking a gas pipe as an example, it is necessary to completely remove air remaining in the pipe when the pipe is finally connected in the pipe construction. If air remains in the pipe, the gas appliance used at the end will not ignite, or even if it ignites, the fire will go out on the way, and if left undisturbed, gas will be released after air is released Began to appear, and as a result,
This is because there is a risk of causing gas poisoning, gas explosion, fire or the like due to gas leakage.

[0003] Similarly, when replacing a defective portion of a pipe, it is necessary to completely remove air from the pipe. Therefore, conventionally, when the gas pipes are finally connected, gas purging is performed as follows. That is, as shown in FIG. 1, gas is supplied to each of the finally connected pipes 1a and 1b, and when gas starts to leak from each pipe end, a squeeze-off tool is provided near the pipe ends of each pipe 1a and 1b. And squeeze to close. Then, the two pipes 1a and 1b are connected by a socket joint 2, and after attaching a bypass saddle joint 3 as shown in FIG. 2, the pipe is pierced through the saddle joint 3 with the cap 4 removed. Thereafter, the squeeze-off tool is removed, and the air in the pipe is released from the saddle joint 3 by gas pressure. During the release, when gas starts to evolve, it is closed with a cap 4 and sealed, or the hole drilled through the saddle joint 3 is plugged and sealed.

Instead of closing the pipe using a squeeze-off tool, as shown in FIG. 3, it can be performed by injecting air into an airbag 6 inserted into the pipe through a bypass saddle joint 3 and inflating the same. .

FIG. 4 illustrates a procedure for replacing the defective portion 8a of the pipe 8, and a pair of bypass saddle joints 3 as shown in FIG. Of each saddle joint 3
So that the gas can be sent through the bypass pipe 9. Next, the inner saddle joint 3 is shown in FIG.
As shown in (2), a pair of airbags 6 are inserted into the upstream side and the downstream side, respectively, and each airbag 6 is inflated to close the pipe 8. Thereafter, the gas is sent through the bypass pipe 9.
After closing the pipe 8, the defective portion 8a is cut and removed, and then
Replace with a new tube and connect with a socket joint.
Thereafter, gas purging is performed as follows.

[0006] Of the two bypass saddle joints 3 on the inner side, air is extracted from the airbag 6 passed through one of the saddle joints 3 and the airbag 6 is pulled out from the saddle joint 3 in a state where the airbag 6 is narrowed. Alternatively, after plugging through the saddle joint 3, the air of the inner airbag 6 is released from the airbag 6 passed through the other saddle joint 3, and the airbag 6 is pulled out from the saddle joint 3. Thereby, the air remaining in the pipe is released from the saddle joint 3 by the gas pressure. When the gas starts to be released, the air is released from the other gas bag 6 on the outside and pulled out from the saddle joint 3, and then covered with a cap or plugged through the saddle joint 3.

In this case, similarly to the above, gas purging can be performed using a saddle joint and a pair of squeeze-off tools.

[0008]

Conventionally, when connecting pipes at the time of final connection of pipes or replacing a defective portion of pipes in the pipe construction using resin pipes, a socket joint and a bypass saddle joint are required as described above. .

SUMMARY OF THE INVENTION The present invention provides a purge joint which can reduce the number of steps required for final connection of a pipe or replace a defective part of a pipe, thereby reducing the number of steps and improving workability. An object of the present invention is to provide a construction method and a purge method.

[0010]

The invention according to claim 1 is used at the time of final connection of pipes in piping construction with resin pipes,
Alternatively, it is a joint for purging used when replacing a defective portion of a pipe made of a resin pipe, and is provided with a purge port such as a spigot, and prevents leakage of fluid from the purge port to a cheese joint-like joint connecting the pipes. It is characterized in that sealing means is provided.

In the present invention, the purging of the unnecessary fluid remaining in the pipe can be performed by the same method as the above-mentioned conventional method. According to the invention, the connection of the tubing and the purging of the waste fluid are performed at one joint.

[0012] The purge port of the purge joint of the present invention takes the form of a spigot. As a joint having such a spigot, there is a cheese joint, but a spigot is provided in a body protruding from the joint so as to protrude laterally, and a saddle portion of the service tee joint is formed in a socket joint shape. It may be one that has been made.

The former cheese joint has one purge port, and the latter service-tee joint type has two purge ports, ie, a body end and a spigot. Purging is possible from any of them. Is simpler in structure, and it is simpler to seal the purge port, since it is sufficient to seal one spot of the spigot.

The present invention is suitably applied to gas piping, but can also be applied to piping for passing other fluids. Claim 2
According to the present invention, the sealing means of the present invention comprises a cap attached to the purge port, preferably screwed to close the purge port, and an o-ring interposed between the cap and the purge port. The invention according to claim 3 is characterized in that the sealing means is formed of a seal plug which is fitted to a purge port or which is fitted to a hole formed in a resin pipe through a purge joint. I do.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the purge joint has a heating wire buried in an inner peripheral surface which is a joint surface with the resin tube, and is electrically fused to the tube by energization. It is an electrofusion joint.

According to the present invention, the fusion bonding with the tube can be performed reliably and efficiently. The invention according to claim 5 is a construction method in which the joint for purging according to any one of claims 1 to 4 is a joint capable of tying a resin pipe.
When connecting pipes at the time of final connection of pipes or replacing defective pipes and connecting the new pipe to the original pipe, after passing the above-mentioned purge joint through one of the connected pipes It is characterized in that the other pipes are opposed to each other, and then the purge joint is shifted so as to extend over both pipes, and then fusion-bonded to both pipes.

According to a sixth aspect of the present invention, there is provided the purging joint according to the first to fourth aspects of the present invention, wherein the purging joint has a step on the inner periphery so that a predetermined amount of the resin pipe can be inserted. This is an enforcement method for joints that are not possible.When pipes are finally connected at the time of piping work, one pipe and connecting pipe are connected using a connecting pipe, and then the other pipe is connected using a connecting pipe. When connecting the pipe and the connecting pipe using a socket joint and replacing the defective part of the pipe with a new pipe and connecting the new pipe to the original pipe, one of the original pipe and the new pipe must be connected. After connecting using a purge joint, the other tube and the new tube are connected using a socket joint.

[0018] The invention according to claim 8 is the invention according to claims 5 to 7.
It relates to a method of discharging and purging unnecessary fluid remaining in the pipe after construction according to the construction method of the invention described, and prior to the final connection of the pipe at the time of construction of the pipe or replacement of a defective part of the pipe. The pipe is closed by a pipe closing means at an appropriate distance from the pipe end face or the expected cutting line, and after the application according to the construction method according to claim 4 to 7, the sealing by the sealing means is released. home,
The blockage by one of the pipe closing means is released, and unnecessary fluid remaining in the pipe is purged through a purge port for purging, and then sealed by the sealing means.

The pipe closing means used in the present invention includes, for example, a squeeze-off tool and an air bag shown in FIG.
The method using a squeeze-off tool is simple, and the workability is good and preferable.

[0020]

FIG. 5 shows a purge joint according to an embodiment of the present invention. The joint 11 is provided with a heating wire on an inner peripheral surface in which a resin pipe is inserted and in contact with the resin pipe. Is a so-called electrofusion joint in which fusion bonding with a resin pipe is performed by energization. In a conventional electrofusion cheese joint 12 shown in FIG. 6, a screw is formed on an outer peripheral surface of a spigot 13 as a purge port. And a peripheral groove is formed, an o-ring 14 is fitted in the peripheral groove, and a cap 15 which constitutes a sealing means together with the o-ring 14 is covered from above the spigot 13 and screwed and attached. There is no step on the inner peripheral surface, and the inner peripheral surface is slidably fitted into the resin tube so that a so-called knotting pipe can be formed.

When the resin pipes are finally connected in the pipe construction of the gas pipe, which is an example of use of the present invention, as shown in FIGS. 7 and 8, the pipe ends of both pipes 16a and 16b to be connected are connected. Squeeze-off is performed using a squeeze-off tool 17 which is a pipe closing means, and the purging joint 11 is passed through one resin pipe 16a using a purging joint 11 shown in FIG. 5, and then both resin pipes 16a and 16b are connected. After the shaft cores are aligned and aligned on a straight line, the purge joint 11 is shifted over the other resin tube 16b and straddles both resin tubes 16a and 16b.

Then, the purge joint 11 is energized for a predetermined time to fuse and join the purge joint 11 and the resin tubes 16a and 16b. After the fusion bonding, the cap 15 of the purge joint 11 is formed.
Then, the squeeze-off tools 17 on both sides are removed to release the squeeze-off. Along with this, the air of the unnecessary fluid remaining in the pipe is released by gas pressure from the spigot 13 which is the purge port of the purge joint 11, and is gas-purged. When gas, which is a useful fluid, starts to come out, cover the end of the spigot 13 with a cap 15 and screw it in to attach.
Seal.

FIG. 9 shows a method of connecting pipes when a purge joint has a step on its inner peripheral surface and a cheese joint which cannot be tied is used. The resin pipes 19a and 19 to be connected are shown.
b, a resin pipe 19c is interposed therebetween, and the resin pipe 19a and the resin pipe 19c are connected by the joint 11 for purging, and then the resin pipe 19b and the resin pipe 19c are connected by an electrofusion socket joint 21. Prior to the connection of the resin tubes 19a, 19c,
9b is squeezed off with a squeeze-off tool and the resin pipe 1
After connecting 9c, gas purging is performed in the same manner as in the above embodiment, and sealing is performed after gas purging.

FIGS. 10 and 11 show a construction method for replacing a defective portion of the gas pipe with the defective portion 23c.
The same bypass saddle joint 24 as the conventional bypass saddle joint is fused to each of the resin pipes 23a and 23b on both sides of the joint, and both joints 24 are connected by the bypass pipe 25 so that gas can be sent through the bypass pipe 25. Later
The squeeze-off tool 17 is used to squeeze off the resin pipes 23a and 23b on both sides of the defective portion 23c.
Thereafter, the defective portion is cut and removed, and replaced with a new tube 23d. Then, the pipe 23d is connected to the one resin pipe 23a with the joint 11 for purging, and the pipe 23d is connected to the other resin pipe 23b with the socket joint 21. After connecting the two resin tubes 23a and 23b via the tube 23d, the squeeze-off tool 17 is removed, and the air remaining in the tubes is removed by the joint 1
Purge from 1.

Each of the joints of the above embodiments has a cheese joint shape in which a spigot is protruded from the joint, but in another embodiment, a spigot protrudes from the side on a body portion protruded from the joint. The shape of the formed service tee is formed. In this case, purging can be performed from any of the two purging ports, that is, the body and the spigot.

In each of the above embodiments, the squeeze-off tool 17 is used as the pipe closing means. As shown in FIG. 3, the bypass saddle joint 3 is attached, and the airbag 6 is inserted into the pipe through the joint to inflate the pipe. By doing so, the tube may be closed.

In each of the above embodiments, an example in which the present invention is applied to a gas pipe has been described. However, the present invention can be similarly applied to a pipe through which a liquid such as a gas or water passes.

[0028]

According to the joint for purging of the first aspect of the present invention, the connection between the resin tubes and the purging of the unnecessary fluid are performed, and the connection and the purging of the tubes are performed using separate joints. In comparison with this, the number of parts can be reduced, the number of steps can be reduced, and workability can be improved.

According to the second aspect of the present invention, a cap is attached to the outlet, and in the third aspect of the present invention, the seal plug is fitted to a hole formed in a purge port or a pipe. This makes it easy to seal. Then, the workability of the fusion work can be improved. When the purge joint is a joint capable of connecting pipes as in the invention of claim 5, the pipes can be connected only by the purge joint.

According to the sixth and seventh aspects of the present invention, even if the purge joint is a joint that cannot be tied and connected, the pipe can be connected by combining with the socket joint.

According to the eighth aspect of the present invention, the unnecessary fluid remaining in the pipe can be purged.

[Brief description of the drawings]

FIG. 1 is a diagram showing a conventional example when pipes are finally connected in piping work.

FIG. 2 is a front view of a bypass saddle joint.

FIG. 3 is a view showing a state where an airbag is inserted through a bypass saddle joint.

FIG. 4 is a diagram showing when a defective portion of a pipe is replaced.

FIG. 5 is a partial cross-sectional front view of a purge joint.

FIG. 6 is a front view of a conventional cheese joint.

FIG. 7 is a schematic diagram when pipes are finally connected in piping work.

FIG. 8 is a schematic diagram when performing a gas purge.

FIG. 9 is a schematic diagram showing a pipe connection method when a purge joint that cannot perform knotting is used.

FIG. 10 is a schematic diagram at the time of construction when replacing a defective portion of a pipe.

FIG. 11 is a schematic diagram when performing gas purging.

[Explanation of symbols]

11. Fitting for purging 12. Electrofusion fitting 13. Spigot 14. O-ring 15. Cap 16a, 16b, 19a, 19b, 19c, 23a, 2
3b, 23d Pipe 17 Squeeze-off tool 24 Bypass saddle joint 25 Bypass pipe

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naotake Udashi 1-2-1, Waki-cho, Waki-machi, Kuga-gun, Yamaguchi Prefecture Inside Mitsui Chemicals, Inc. (72) Inventor Hiroaki Tanaka 6, Waki-cho, Waki-cho, Kuga-gun, Yamaguchi Prefecture 1-2 No. 2 in Mitsui Chemicals, Inc. (72) Inventor Hiroshi Goshiro 3-5 Kasumigaseki, Chiyoda-ku, Tokyo F-term in Mitsui Chemicals, Inc. 3H019 BA04 BB02

Claims (8)

[Claims] 1. A purging joint which is used at the time of final connection of a pipe in a pipe construction using a resin pipe or used when replacing a defective portion of a pipe made of a resin pipe, comprising a purge port such as a spigot, A joint for purging, wherein a joint for connecting pipes is provided with a sealing means for preventing leakage of fluid from a purge port. 2. The apparatus according to claim 1, wherein said sealing means comprises a cap attached to the purge port to close the purge port, and an o-ring interposed between the cap and the purge port.
A purge joint as described. 3. The purging apparatus according to claim 1, wherein said sealing means comprises a seal plug fitted into a purge port or fitted into a hole formed in a resin pipe through a purge joint. Fittings. 4. A purging joint, wherein a heating wire is buried in an inner peripheral surface which is a joining surface with a resin tube, and the tube is an electrofusion joint which is electrically fused by energization. A purge joint as described. 5. A joint for purging, which is capable of tying a resin pipe through a knotted pipe, when a pipe is finally connected at the time of piping, or by replacing a defective portion of the pipe, and replacing the new pipe with the original pipe. When connecting the pipes, the purge joint is passed through one of the pipes to be connected, and then the other pipe is faced.Then, the purge joint is shifted so as to span both pipes, and then fused to both pipes. 5. The method according to claim 1, wherein the bonding is performed.
The construction method using the joint for purging described above. 6. A joint in which a purging joint has a step on an inner peripheral surface to allow a fixed amount of a resin tube to be inserted thereinto, and cannot be knotted. The method according to any one of claims 1 to 4, wherein the connecting pipe is used to connect one pipe and the connecting pipe using a purge joint, and then the other pipe is connected to the connecting pipe using a socket joint. A purge joint as described. 7. A joint in which a purging joint has a step on an inner peripheral surface and a fixed amount of a resin tube can be inserted thereinto, and knotting piping is impossible. When the new pipe is connected to the old pipe by replacement, one of the old pipe and the new pipe is connected using the purge joint, and then the other pipe and the new pipe are connected to the socket joint. The joint for purging according to any one of claims 1 to 4, wherein the joint is used for connection. 8. When pipes are finally connected at the time of pipe installation, or when a defective portion of the pipe is replaced, a portion which is an appropriate distance from an end face of the pipe or a planned cutting line is closed by a pipe closing means. Next, after the application according to the enforcement method according to claim 5 to 7, the sealing by the sealing means is released, and then the blocking by one of the pipe closing means on both sides is released, and the unnecessary fluid remaining in the pipe is purged. A purging method characterized by purging through an opening and then sealing with the sealing means.