JP2000257772A - Detachment preventive tube fitting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a set bolt to press a lock ring. SOLUTION: An annular seal material 6 is arranged between an inner periphery of a socket 2 and an outer periphery of an insert port 4 and a compression mechanism 11 to compress the seal material 6 is provided on a part on the deep side of the socket 2 rather than a head end of the insert port 4 on this tube fitting. A lock ring storage groove 18 is formed on the inner periphery of the socket 2 on the opening side rather than the seal material 6, and an annular lock ring 19 is stored. An annular groove 24 is formed on the outer periphery of the insert port 4, and the lock ring 19 is engaged with it in a tightened state. Outer peripherally directed tapered surfaces 22, 23 are formed on a side part on the socket opening side and a side part on the socket deep side on the lock ring 19, and inner-peripherally directed tapered surfaces 20, 21 in correspondence with the tapered surfaces 22, 23 of the lock ring 19 are formed on a side part on the socket opening side and a side part on the socket deep side in the lock ring storage groove 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint for preventing separation.

[0002]

2. Description of the Related Art As a pipe joint for a ductile cast iron pipe used for a water pipe, an annular sealing material is arranged between an inner periphery of a receiving port and an outer periphery of a receiving port, and a pipe fitting is provided from a leading end of the receiving port. Also, there is known an apparatus provided with a compression mechanism for compressing a sealing material in a portion on the back side of the receptacle. Also, as other fittings,
There is also known an arrangement in which an annular sealing material is disposed between the inner periphery of the opening of the receiving port and the outer periphery of the insertion opening, and the sealing material is compressed by a pressing ring fastened to an end of the receiving opening. ing. Among these pipe joints, those having detachment prevention performance are known.

Conventionally, in order to provide a pipe joint of this type with a detachment preventing function, a lock ring accommodating a circumferential direction is accommodated in a lock ring accommodating groove on an inner periphery of a receiving port of one of the pipes. An annular groove is formed on the outer periphery of the insertion opening of the other pipe inserted into the opening, and a plurality of set bolts in the circumferential direction are threaded from the outer periphery of the receiving opening through the wall of the receiving opening into the lock ring receiving groove. As a result, the outer peripheral surface of the lock ring is pressed, and the lock ring is tightened in the annular groove of the insertion port while being held in the lock ring housing groove.

[0004] When a detachment force acts on the joint from the ground, the lock ring accommodating groove, the lock ring and the annular groove are caught in the axial direction with each other, so that the required detachment prevention performance can be exhibited. Is configured. In order to ensure the performance of the lock ring to prevent detachment, the following points must be realized.

[0005] The lock ring does not float up from the annular groove, and is located at a position where the lock with the annular groove can be maintained.・ The receiving port and the insertion port are not eccentric. -The lock ring must not be twisted when a release force is applied. Conventionally, these necessary items are realized by pressing the outer peripheral surface of the lock ring with a plurality of set bolts in the circumferential direction as described above.

[0006]

In recent years, there has been a request from users to use a ductile cast iron pipe having such a pipe joint having a detachment prevention function for a pipe in a tunnel or a pipe in an existing pipeline. ing. However, in these tunnels and existing pipelines, the gap between the newly installed ductile cast iron pipe and the inner surface of tunnels and existing pipelines is generally narrow.
There is a problem that it is difficult to apply the set bolt from the outer surface of the receiving port when joining the pipes.

Accordingly, an object of the present invention is to solve such a problem and to realize a separation preventing pipe joint having a configuration in which set bolts are omitted.

[0008]

In order to achieve this object, the present invention provides an annular sealing member between an inner periphery of a receiving port and an outer periphery of a receiving port, and a receiving port located closer to the tip of the receiving port. In a pipe joint provided with a compression mechanism for compressing a sealing material at a portion on the back side of the seal ring, a lock ring receiving groove is formed on an inner periphery of a receiving port on an opening side of the sealing material, and an annular lock ring is formed in the lock ring receiving groove. Is accommodated, and an annular groove is formed on the outer periphery of the insertion port,
Fit the lock ring into this annular groove in a tight state,
A taper surface facing the outer periphery is formed on the side of the lock opening on the side of the receiving opening and the side on the back of the receiving opening, and the side of the locking ring receiving groove on the receiving opening side and the side on the receiving back are formed. In addition, a taper surface facing inward corresponding to the taper surface of the lock ring is formed.

Further, according to the present invention, an annular sealing member is arranged between the inner periphery of the opening of the receiving opening and the outer periphery of the insertion opening, and the sealing material is compressed by a pressing ring fastened to the end of the receiving opening. In the pipe joint configured as described above, a lock ring receiving groove is formed on the inner periphery of the receiving port on the back side of the seal material, an annular lock ring is stored in this lock ring receiving groove, and an annular groove is formed on the outer periphery of the insertion port. A lock ring is fitted in this annular groove in a tightened state, and a tapered surface facing the outer periphery is formed on the side of the lock ring on the side of the receiving opening and the side of the receiving side on the back side. The inner peripheral side tapered surface corresponding to the tapered surface of the lock ring is formed on the side portion on the receiving port opening side and the side portion on the receiving side deep side in the above.

In such a configuration, when a detaching force is applied to the joint from the ground, the side of the annular groove on the inner side of the receiving hole is caught by the lock ring, and the tapered surface of the lock ring is formed by the lock ring receiving groove. Press the tapered surface. Then
An inward force along the radial direction is applied to the lock ring from the tapered surface of the lock ring receiving groove by the reaction,
The lock ring is strongly pressed by the annular groove and is reliably caught in the axial direction, so that the required detachment prevention performance is exhibited.

When a large pushing force acts on the joint from the ground, the lock ring is similarly caught in the annular groove by the action of the tapered surface. For this reason, the insertion hole is prevented from entering the inside of the reception port more than necessary, which may cause a situation where the insertion hole reaches, for example, the compression mechanism and adversely affects the compression mechanism. Is reliably prevented.

Therefore, according to the present invention, an annular sealing member is arranged between the inner periphery of the receptacle and the outer periphery of the insertion port, and the sealing member is compressed to a portion on the back side of the receptacle from the sealing material. A detachable pipe joint provided with a compression mechanism, and an annular sealing material disposed between the inner periphery of the opening of the receiving opening and the outer periphery of the insertion opening, and the sealing material is fastened to the end of the receiving opening by a pressing ring. Can be realized without using a set bolt for pressing the lock ring.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a pipe joint for preventing separation according to an embodiment of the present invention. As shown here, a socket 2 is formed at the end of one ductile cast iron pipe 1 joined to the underground and inserted into the inside of the socket 2 at the end of the other ductile cast iron pipe 3. The insertion hole 4 to be formed is formed.

On the inner periphery of the receiving port 2, a tapered sealing material pressure contact surface 5 facing the back side of the receiving port 2 is formed, and between the sealing material pressing surface 5 and the outer peripheral surface of the insertion opening 4. Accommodates an annular rubber seal member 6. An inner peripheral surface 7 and a rear end surface 8 are formed in a portion of the receiving port 2 on the back side of the sealing material pressing surface 5. Receiving port 2 rather than tip surface 9 of insertion port 4
The inner peripheral surface 7 and the rear end surface 8
An annular space 10 is formed, which is surrounded by a tip surface 9 of the seal member. A compression mechanism 11 for compressing the seal material 6 between the seal material pressing surface 5 and the outer peripheral surface of the insertion opening 4 is formed in the annular space 10. Is provided. The compression mechanism 11 includes a pressing wheel 12 in which divided pieces divided into a plurality along the circumferential direction are assembled in an annular shape,
A plurality of bolts 13 in the circumferential direction screwed to the pressing ring 12 in the tube axis direction, and a connecting rod 15 in the tube axis direction provided between the head 14 of the bolt 13 and the rear end face 8 of the socket 2.
The tip 13 of the pressing ring 12 compresses the sealing material 6 based on the reaction force caused by the bolt 13 being unscrewed from the pressing ring 12 and the connecting rod 15 pressing the rear end face 8, whereby It is configured such that a predetermined sealing performance can be exhibited between the receiving port openings.

A lock ring accommodating groove 18 is formed in the inner periphery of the receiving port 2 on the opening side of the sealing material pressing surface 5. A lock ring 19 is housed. Tapered surfaces 20 and 21 facing inward are formed on the side of the lock ring housing groove 18 on the side of the receiving opening and the side on the back side of the receiving, respectively. These tapered surfaces 20 and 21 are formed so as to be inclined at an angle of, for example, 30 degrees with respect to the pipe diameter direction. The side of the lock ring 19 on the opening side of the receiving opening and the side on the back side of the receiving opening correspond to the tapered surfaces 20 and 21 of the receiving groove 18, for example, the same as the tapered surfaces 20 and 21 of the receiving groove 18. These tapered surfaces 2 are formed at an angle.
0, 21 can be in contact with the outer peripheral tapered surface 2
2, 23 are formed.

An annular groove 24 in which the lock ring 19 is fitted in a tight state is formed on the outer periphery of the insertion opening 4.
Hook portions 25 and 26 that can be hooked on the side wall of the annular groove 24 are formed in the lock ring 19 in the radial direction. As shown in the figure, when the lock ring 19 is fitted into the annular groove 24 of the insertion opening 4 in a tightly fitted state, there is a gap between the outer peripheral surface of the lock ring 19 and the inner peripheral surface of the housing groove 18. A space 27 is provided for the lock ring 19 to elastically expand its diameter. That is, the lock ring 19 is housed in the lock ring housing groove 18 when no external expanding force is applied, but the outer diameter thereof is smaller than the inner diameter of the lock ring housing groove 18. It is formed with.

In such a configuration, the receiving port 2 and the insertion port 4
When the sealing member 6 and the compression mechanism 11 are accommodated in the receiving port 2,
The insertion port 4 is inserted into the receptacle 2 in which the lock ring 19 is accommodated in the socket 8. At this time, the insertion opening 4 is inserted in a state where the lock ring 19 is elastically expanded by a diameter expander or the like using the space 27. Then, the insertion port 4 enters the inside of the receiving port 2 while passing through the inside of the lock ring 19 and the sealing material 6. Instead of using the above-described diameter expanding tool for the lock ring 19, a tapered surface is formed on the outer periphery of the distal end of the insertion port 4, and the lock ring 19 is utilized by utilizing the space 27 by the action of the tapered surface. May be configured so that the insertion opening 4 enters the inside of the receiving opening 2 while elastically pushing and expanding the opening.

When the slot 4 is inserted to a position where the annular groove 24 corresponds to the lock ring 19, the lock ring 19 fits into the annular groove 24 due to its elasticity, and fits into the outer periphery of the annular groove 24 in a tight state. , The state shown in the figure. Next, the worker enters the pipe and pushes the bolt 1
By unscrewing 3, the sealing material 6 can be compressed as shown in the drawing to exhibit the required sealing performance.

In this manner, the joining between the receiving port 2 and the insertion port 4 is completed. In this state, when a large detaching force acts on the joint from the ground, a large exit force acts on the insertion port 4. The tapered surface 22 of the lock ring 19 hooked on the annular groove 24 strongly presses the tapered surface 20 of the housing groove 18, and a reaction inward applies an inward force in the radial direction from the tapered surface 20 to the lock ring 19. Is done.
For this reason, the lock ring 19 is strongly pressed by the annular groove 24, and the hooked portion 25 is securely hooked on the side wall of the annular groove 24, so that the required detachment prevention performance is exhibited.

On the other hand, when a large pushing force acts on the joint from the ground, the tapered surface 23 of the lock ring 19 strongly pushes the tapered surface 21 of the accommodation groove 18, and similarly, the lock ring 19 and the annular groove 24 is securely caught. For this reason, the opening 4 is more than the receiving port 2
Is prevented from getting inside. As a result, the insertion 4
Is prevented from arriving at the compression mechanism 11 and thereby adversely affecting the compression mechanism 11.

In this manner, the tapered surfaces 20 to 23 of the housing groove 18 and the lock ring 19 provide the following:
The role of the conventional set bolt can be replaced.
The lifting of the lock ring 14 from the annular groove 24 when the separating force acts as described above can be prevented. The eccentricity between the receiving port 2 and the insertion port 4 when the separating force is applied is suppressed.

Since the pressing force against the annular groove 24 is applied to the lock ring 19, the lock ring 19 is unlikely to be twisted when a separating force is applied, so that a large separation preventing performance can be expected. Therefore, a pipe joint having detachment prevention performance can be realized without using a set bolt for pressing the lock ring 19. Therefore, this type of earthquake-resistant pipe joint can be easily used for pipes in tunnels and pipes in existing pipes.

FIG. 2 shows a pipe joint for preventing separation according to another embodiment of the present invention. Here, one ductile cast iron tube 1
On the inner circumference of the opening of the receiving port 2, a tapered sealing material pressing surface 5 facing the opening side of the receiving port 2 is formed, and an annular shape is formed between the sealing material pressing surface 5 and the outer peripheral surface of the insertion opening 4. The rubber sealing material 6 is accommodated. A flange 31 is formed on the outer periphery of the opening of the receiving port 2, and the pressing ring 32 fitted in the insertion port 4 is fastened to the flange 31 by a T-head bolt / nut 33, and the sealing material 6 is formed by the pressing ring 32. Is compressed,
Thereby, it is configured such that a predetermined sealing performance can be exhibited between the receiving port openings. The distal end surface 9 of the insertion opening 4 is located close to the rear end surface 8 of the receiving opening 2.

The lock ring accommodating groove 18 of the receiving port 2 is formed on the inner periphery of the receiving port 2 on the back side of the sealing material pressing surface 5. The configuration of the tapered surfaces 20 and 21 formed in the lock ring storage groove 18 and the configuration of the tapered surfaces 22 and 23 of the lock ring 19 stored in the lock ring storage groove 18 are the same as those in FIG. Yes, it has the same effect.

FIG. 3 shows another example of the configuration of the lock ring housing groove 18. That is, in the lock ring accommodating groove 18 shown in FIG. 1 and FIG.
The lock ring accommodating groove 18 of FIG. 3 has an inner peripheral side portion,
That is, only the portions that are in contact with the tapered surfaces 22 and 23 of the lock ring 19 that are fitted in the annular groove 24 of the insertion opening 4 are formed as the tapered surfaces 20 and 21. The other portion 34 of the lock ring housing groove 18 is formed to have a normal rectangular cross section. Even in such a configuration, similarly, the tapered surfaces 20 and 21 and the tapered surface 2
The function and effect by contact with 2, 23 can be exhibited.

[0026]

As described above, according to the present invention, an annular sealing material is arranged between the inner periphery of the receptacle and the outer periphery of the insertion port, and the sealing material is disposed between the tip of the insertion port and the back side of the reception port. In a pipe joint provided with a compression mechanism for compressing a sealing material, an annular sealing material is arranged between an inner periphery of an opening of a receiving opening and an outer periphery of an insertion opening, and a press ring fastened to an end of the receiving opening. In the pipe joint configured to compress the seal material, a lock ring receiving groove is formed on the inner periphery of the receiving port, an annular lock ring is stored in the lock ring receiving groove, and an annular groove is formed on the outer periphery of the insertion port. And a lock ring is fitted in this annular groove in a tightened state, and a tapered surface facing the outer periphery is formed on the side of the lock ring on the side of the receiving opening and the side of the receiving side on the back side, and the lock ring is accommodated. To the side of the groove on the opening side of the socket and the side on the back side of the socket Since a taper surface facing inward corresponding to the taper surface of the lock ring is formed, a pipe joint having detachment prevention performance can be realized without using a set bolt for pressing the lock ring. In addition, this type of separation preventing pipe joint can be easily used for pipes in tunnels and pipes in existing pipes.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a separation-preventing pipe joint according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main part of a separation-preventing pipe joint according to another embodiment of the present invention.

FIG. 3 is a view showing another example of the lock ring housing groove according to the present invention.

[Explanation of symbols]

 Reference Signs List 2 receiving port 4 insertion port 6 sealing material 11 compression mechanism 18 lock ring accommodation groove 19 lock ring 20, 21 taper surface 22, 23 taper surface 24 annular groove

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akira Nakayama 2-26, Ohama-cho, Amagasaki-shi, Hyogo F-term in Kubota Mukogawa Works (reference) 3H015 FA01 FA06

Claims (2)

[Claims] A compression mechanism for arranging an annular sealing material between an inner periphery of a receiving opening and an outer periphery of an inserting opening and for compressing the sealing material at a portion of the receiving opening farther than a leading end of the inserting opening. The pipe joint provided, wherein a lock ring receiving groove is formed on the inner periphery of the receiving port on the opening side of the sealing material, an annular lock ring is received in the lock ring receiving groove, and an annular groove is formed on the outer periphery of the insertion port. A lock ring is fitted in this annular groove in a tightened state, and a tapered surface facing the outer periphery is formed on the side of the lock ring on the side of the receiving opening and the side of the receiving side on the back side. And a taper surface facing inward corresponding to the tapered surface of the lock ring is formed on a side portion on the side of the receiving opening and a side portion on the side on the inner side of the receiving port. 2. An arrangement in which an annular sealing material is disposed between an inner periphery of an opening of a receiving opening and an outer periphery of an insertion opening, and the sealing material is compressed by a pressing ring fastened to an end of the receiving opening. Pipe joint, a lock ring receiving groove is formed on the inner periphery of the receiving port on the back side of the sealing material, an annular lock ring is received in the lock ring receiving groove, and an annular groove is formed on the outer periphery of the insertion port. Then, the lock ring is fitted in the annular groove in a tightened state, and a tapered surface facing the outer periphery is formed on the side of the lock ring on the side of the receiving opening and the side of the receiving side on the back side. A detachable pipe joint, wherein tapered surfaces facing the inner circumference corresponding to the tapered surface of the lock ring are formed on the side portion on the opening side of the receiving port and the side portion on the inner side of the receiving port.