JPH08200583A - Pipe coupling, and leakage preventing and leakage detecting system for pipe coupling - Google Patents

Abstract

PURPOSE: To reliably perform detection of leakage (confirmation of sealing properties) and prevention of discharging of inside fluid to the outside in the leakage. CONSTITUTION: A pipe coupling is formed by combination of an internal side coupling 50 with an external side coupling 52, and both couplings are provided with self-closing valve mechanisms by springs and has a structure wherein a fluid passage communicates after the self-closing valve mechanisms are opened in connecting of the couplings, and the connection of mutual coupling main bodies is held by a locking mechanism. An intermediate pressurizing space 80 is provided on connecting parts of the external side coupling to the internal side coupling, and an introducing hole 82 for pressurized fluid from the outside is so provided as to communicate with the space. O-rings 84, 86, 88 are respectively provided on the tip surface of the external side coupling main body and two parts pinching the external coupling side main body tip surface on the inner peripheral surface of the internal side coupling main body, and the annular intermediate pressurizing space is formed. A piping 90 is connected to the introducing hole for pressurized fluid, and a pressurized fluid supplying device 91 and a fluid pressure detecting device 92 are provided on it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint capable of preventing and detecting leaks. More specifically, an intermediate pressurizing space is provided at a connecting portion between a male side joint and a female side joint, and the space is provided from the outside. The present invention relates to a pipe joint in which a pressurized fluid can be introduced and the pressure in the intermediate pressurizing space can be constantly monitored to prevent leakage and detect leakage. This technology is required to completely prevent internal fluids from leaking outside, such as chemical, gas, and petroleum plants, as well as those related to nuclear power, and to connect and disconnect pipes for operation and maintenance. It is useful for pipe joints that require

[0002]

2. Description of the Related Art An example of a conventional pipe joint is shown in FIG. In the figure, A is a state at the time of connection, and B is a state at the time of disconnection. The pipe joint is composed of a combination of a female side joint 10 and a male side joint 12, and both joints are equipped with a self-closing valve mechanism by a spring inside the joint body. That is, the female joint 10 is provided with a valve mechanism including a coil spring 16 and a valve body 18 in a female joint body 14, and in a separated state, the valve body 18 is repulsed by the coil spring 16 so that the valve body 18 is in the female side. Inner peripheral protruding wall 14 of joint body 14
It is pressed against a and keeps closed. Similarly, in the male joint 12, a valve mechanism including a coil spring 22 and a valve body 24 is provided in the male joint body 20, and in a separated state, the valve body 24 is repulsed by the elastic force of the coil spring 22. The closed state is maintained by being pressed against the tip projecting wall 20a of the side joint body 20.

When the joint is connected, the self-closing valve mechanism is opened against the elastic force of the spring to connect the flow path. That is, when the male joint 12 is pushed into the female joint 10,
The tip surfaces of the valve bodies 18, 24 of both joints are in close contact with each other,
The flow paths are formed by pushing them inward and opening them. The female body joint 10 is used to hold the connection between the joint bodies.
Of the sleeve 26 provided on the outer periphery of the ball, the ball 28 held inside the sleeve, and the annular groove 3 formed on the outer periphery of the male joint 12.
It is done by a locking mechanism with 0. When disconnecting,
The sleeve 26 may be pulled out against the elastic force of the spring 32 on the inside thereof to free the ball 28, whereby the male side joint 12 can be separated from the female side joint 10. Prevention of leakage during connection is ensured by an O-ring 34 provided inside the female joint 10.

Conventionally, the function maintenance such as the sealing property of the pipe joint has been performed by the periodical replacement of the O-ring 34 and the leakage inspection. In addition, the confirmation of the connectivity during the period of use is made visually by the worker.

[0005]

The above-mentioned conventional pipe joints are focused on the purpose of development that they can be easily connected / disconnected, and the function at the time of connection can be confirmed visually by the operator. Since it was conducted by a leak test before use, it was impossible to remotely check the connectivity, sealability, and the presence or absence of leak during use at all times. In particular, in the field of nuclear power and the like, there is a need for a pipe joint that never leaks the contained fluid to the outside, and in that case, there is a great demand for remote monitoring for the presence or absence of leakage, but this was not possible with the prior art.

An object of the present invention is to detect leakage (confirm the sealing property) and to prevent the contained fluid from being released to the outside at the time of leakage, thereby improving safety. It is to provide a joint. Another object of the present invention is to provide a system capable of preventing leakage and detecting leakage when a pipe joint is used.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a combination of a female joint and a male joint, both joints each having a self-closing valve mechanism with a spring inside the joint main body, and at the time of joint connection. The self-closing valve mechanism is a pipe joint which can be opened and closed against the elastic force of the spring to connect the flow passages, and in which the joint bodies are held together by a locking mechanism so as to be freely separable. Here, the feature of the present invention is that an intermediate pressurizing space is provided at the connecting portion between the male side joint and the female side joint, and an introduction hole for pressurized fluid from the outside is provided so as to communicate with the intermediate pressurizing space. is there. For example, a seal member is provided at each of two positions on the inner end surface of the male joint body and the inner peripheral surface of the female joint body sandwiching the male joint body end surface, and these three seal members form an annular shape. The intermediate pressurizing space is formed, and the female joint body is provided with an introduction hole for the pressurized fluid from the outside.

A leak prevention / leakage detection system using such a pipe joint includes a pressurized fluid supply device for connecting a pipe to a pressurized fluid introduction hole of the pipe joint and supplying a pressurized fluid to the pipe.
And a fluid pressure detection device for detecting the pressure of the pressurized fluid. For example, the pressurized fluid supply device is composed of a pressurized fluid supply source that supplies a clean pressurized fluid and a solenoid valve provided on the outlet side thereof, and the fluid pressure detection device detects the pressure sensor and its electrical output. It will consist of a pressure display alarm that is displayed at a remote location. If necessary, a pressure gauge that can be monitored on site may be provided.

[0009]

If the pressurized fluid is introduced from the outside into the space for intermediate pressurization, the pressurized fluid from the outside will not flow into the interior of the fitting even if connection failure or seal member failure occurs in the fitting. It will enter and the contained fluid will not leak out. That is, leakage of the contained fluid to the outside can be completely prevented. Further, if the pressure of the pressurized fluid is constantly monitored, it is possible to detect the connection failure and the defect of the seal member at an early stage by reducing the pressure.

[0010]

1 is an explanatory view showing an embodiment of the pipe joint according to the present invention, and FIG. 2 shows the separated state.
This pipe joint is composed of a combination of a female side joint 50 and a male side joint 52, and both joints are equipped with a self-closing valve mechanism by a spring inside the joint body. That is, the female joint 50 includes a valve stem 55 fixed to the center of the female joint main body 54, and a packing holder 58 that slides in the axial direction with respect to the inner peripheral surface of the female joint main body 54 on the outside thereof. A valve mechanism having a coil spring 56 that repels the packing holder 58 outward in the axial direction is provided. In the separated state shown in FIG. 2, the packing 59 on the front end surface of the packing holder 58 presses the rear surface of the front end of the valve stem 55 to maintain the closed state. The male joint 52 is a male joint body 60.
A valve mechanism having a coil spring 62 and a valve body 64 is provided inside, and in the separated state, the valve body 64 is repelled axially outward by the repulsive force of the coil spring 62, and the packing 65 thereof is on the male side. The front end inner wall 60a of the joint body 60 is pressed to maintain a closed state.

When the joint is connected, the self-closing valve mechanism is
It is opened against the elastic force of the spring and connects the flow path.
That is, when the male joint 52 is pushed into the female joint 50, the tip surface of the male joint body 60 contacts the tip surface of the packing holder 58 to push the packing holder 58, and at the same time, the tip surface of the valve stem 55 contacts the valve body 64. Push in the valve body 64. With this, it becomes open state,
A flow path is formed. And holding the connection between the joint bodies,
A ball 68, which is held by a ball holder 67 so as to be retractable in the radial direction on the outer circumference of the female joint 50, an axially movable sleeve 66 provided on the outer circumference of the male joint body 60, and an annular shape into which the ball 68 is fitted. This is done by a locking mechanism consisting of the groove 70. At the time of disconnection, the sleeve 66 may be pulled out against the elastic force of the spring 72 inside thereof to free the ball 68, whereby the male joint 52 can be separated from the female joint 50.

A feature of the present invention is that an intermediate pressurizing space 80 is provided at a connecting portion between the female side joint 50 and the male side joint 52, and a pressurizing fluid introduction hole from the outside is provided so as to communicate with the intermediate pressurizing space 80. The point 82 is provided. Space 8 for intermediate pressurization here
0 is an O-ring 84 provided on the front end surface of the male joint body 60.
And O-rings 86 and 88 provided at two positions on the inner peripheral surface of the female joint body 54 sandwiching the tip end surface of the male joint body, a total of three sealing members. The intermediate pressurizing space 80 may be formed by a clearance due to a clearance between the inner circumference of the female joint 50 and the outer diameter of the male joint 52. The pressurizing fluid introduction hole 82 is, for example, a hole having a diameter of about 1 cm, and is threaded to connect the pressurizing pipe 90.

A pipe 90 is connected to a pressurizing fluid introduction hole 82 of an intermediate pressurizing space 80 of the pipe joint, and a pressurizing fluid supply device 91 for supplying the pressurizing fluid to the pipe 90 and the pressurizing fluid are provided. And a fluid pressure detection device 92 for detecting pressure. Specifically, for example, as shown in FIG. 3, the pressurized fluid supply device includes a pressurized fluid supply source 94 that supplies clean pressurized fluid,
The fluid pressure detection device is composed of a solenoid valve 95 provided on the outlet side thereof, and the fluid pressure detection device is composed of a pressure sensor 96 and a pressure display alarm device 97 for displaying its electric output at a remote position. If necessary, a pressure gauge 98 for site monitoring may be installed. If remote monitoring is not required, only the pressure gauge may be installed as the fluid pressure detection device.

The operation method of this system is as follows. First, after connecting the pipe joint, the solenoid valve 95 is opened to supply a clean pressurized fluid from the pressurized fluid supply source 94 to the intermediate pressurizing space 80.
Then, the solenoid valve 95 is closed. The pressure of the pressurized fluid may be arbitrary as long as it exceeds the pressure of the contained fluid.
Then, the pressure is continuously monitored by the pressure sensor 96 and the pressure display alarm 97. With this, if pressure cannot be applied immediately after connection, it is possible to detect a poor connection of the pipe joint, and if pressure drops due to pressure monitoring after the solenoid valve is closed, it is determined that leakage has occurred, and early It is possible to issue an alarm to. In this way, it is possible to always remotely confirm and detect the sealing property during the use period, which has been impossible in the past. Further, when leakage occurs due to deterioration of the seal member, this pressurized fluid flows into the inside from the leakage location, and it is possible to prevent the contained fluid from leaking to the outside.

Table 1 shows an example of fluid types and pressures used in the nuclear field.

[Table 1]

Here, the pressure relationship is not limited to the above numerical relationship, as long as the pressure of the pressurized fluid is higher than the pressure of the contained fluid. It is preferable to use the same kind of fluid as described above because it is possible to prevent impurities from being mixed into the inside due to leakage. As the type of fluid, those shown in Table 2 are also assumed.

[0017]

[Table 2]

However, if the pressurized fluid is of a different type from the contained fluid, leakage causes the impurity component of the contained fluid to rise.

FIG. 4 shows an example in which a plurality of pipe joints are installed side by side. A pipe 90 is connected to each of the pressurizing fluid introduction holes of the pipe joint including the female side joint 50 and the male side joint 52, an electromagnetic valve 95 is provided in each pipe 90, and a common pressurized fluid source 94 is provided. Pressurized fluid can be supplied. Further, each of the pipes 90 is provided with a pressure sensor 96, and an electric signal from each pressure sensor 96 is guided to the pressure display alarm device 97.

[0020]

As described above, according to the present invention, the intermediate pressurizing space is provided in the connecting portion between the male side joint and the female side joint, and the introduction hole for the pressurized fluid from the outside is provided so as to communicate therewith. As a result, by introducing a pressurized fluid into the intermediate pressurizing space and monitoring the pressure, it is possible to constantly monitor the sealing performance remotely. At the same time, it is possible to prevent the contained fluid from leaking to the outside when a failure occurs in the seal member.
This significantly improves the safety of the pipe joint. In particular, it is preferable to use a clean fluid of the same type as the inclusion fluid as the pressurized fluid because it is possible to prevent impurities from entering the inside of the pipe joint.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a pipe joint according to the present invention.

FIG. 2 is an explanatory view of the separated state.

FIG. 3 is an explanatory diagram showing an example of a pipe joint, a pressurized fluid supply device, and a fluid pressure detection device.

FIG. 4 is an explanatory view of a case where a plurality of pipe joints are installed side by side.

FIG. 5 is an explanatory diagram showing an example of a conventional technique.

[Explanation of symbols]

 50 Female Joint 52 Male Male Joint 54 Female Joint Main Body 55 Valve Stem 56 Coil Spring 58 Packing Holder 60 Male Side Joint Main Body 62 Coil Spring 64 Valve Main Body 66 Sleeve 68 Ball 70 Annular Groove 72 Spring 80 Intermediate Pressurization Space 82 Inlet Hole 90 Piping 91 pressurized fluid supply device 92 fluid pressure detection device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunihiko Goto Nitto Koki Co., Ltd. 2-9-4 Nakaikenoue, Ota-ku, Tokyo

Claims (4)

[Claims] 1. A combination of a female side joint and a male side joint, both joints each having a self-closing valve mechanism by a spring inside the joint body, and when the joint is connected, the self-closing valve mechanism is For connecting and disconnecting pipe joints that are opened against resistance to repulsion and connect the flow passages, and hold the joint body connections with a locking mechanism, for intermediate pressurization at the connection between the male and female joints. A pipe joint, characterized in that a space is provided and an introduction hole for pressurized fluid from the outside is provided so as to communicate with the space for intermediate pressurization. 2. A seal member is provided at each of two positions sandwiching the end surface of the male joint body and the inner peripheral surface of the female joint body between the end surface of the male joint body, and these three seal members are provided. The pipe joint according to claim 1, wherein an annular intermediate space for pressurization is formed by, and a female-side joint body is provided with an introduction hole for pressurized fluid from the outside. 3. A pressurized fluid supply device which connects a pipe to the pressurized fluid introduction hole of the pipe joint according to claim 1 and supplies the pressurized fluid to the pipe, and detects the pressure of the pressurized fluid. Leakage prevention / leakage detection system for pipe joints equipped with a fluid pressure detection device. 4. The pressurized fluid supply device comprises a pressurized fluid supply source for supplying a clean pressurized fluid and a solenoid valve provided on the outlet side thereof, and the fluid pressure detection device comprises a pressure sensor and its The leak prevention / leakage detection system for a pipe joint according to claim 3, further comprising a pressure display alarm device for displaying an electric output at a remote position.