JPH07167357A - Tube joint and rubber packing - Google Patents

Abstract

PURPOSE:To provide a tube joint with sufficient sealing performance and resistance to drawing force secured only by manual fastening. CONSTITUTION:The inner bottom face of a union nut 14 or a pressure ring and the back face of a rubber packing are respectively placed to face the rear side to form a tapered face 17 of a down grade, and a sheet member formed of synthetitic resin material with excellent self-lubricating ability is interposed between the outer peripheral surface side of the tapered face 18 of the rubber packing 16 and the union nut 14 or pressure ring. Metal wedges 19 are integrally connected to plural places of the inner peripheral surface, corresponding to the outer peripheral surface of a connecting tube 4, of the rubber packing 16, or the metal wedges 19 are embedded in the inner peripheral surface, corresponding to the outer peripheral surface of the connecting tube, of the rubber packing 16, and the surface side of the metal wedges 19 are covered with rubber material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention inserts an end portion of a joint pipe, in which a screw is not engraved, into a receiving portion of a pipe or a joint body,
The present invention relates to a pipe joint of a system in which a metal rubber packing with a wedge and a sheet member having excellent self-lubricating properties are interposed and fastened, and the rubber packing.

[0002]

2. Description of the Related Art In addition to its simple and inexpensive point, a pipe joint with no thread at the pipe end has a flexible expansion and contraction in the joint portion, and as a result, a protective function that absorbs vibration, elongation, strain, etc. of the pipe well. Since it has a diameter of 13 to 50 mm, it has a relatively small diameter and a normal pressure of at most 5 Kg / cm ^2.
It has been used favorably for joining methods of low-pressure pipes to a certain degree.

However, in the conventional pipe joint, the holding force of the rubber packing with respect to the joint pipe is determined according to the tightening force of the union nut at the time of joining work, so that it is necessary to strongly tighten it with a large pipe wrench or the like in a place where pressure is applied. there were.
In addition, if rust-preventing oil, oil during screw cutting, etc. adheres to the pipe, the force to hold the joint pipe is extremely reduced and it is extremely difficult to reliably prevent the joint pipe from coming off. Met.

Therefore, in the past, measures were taken to solve the problem of retaining the joint pipe by using an annular wedge made of metal. This is as shown in FIG. 10 which is a semi-longitudinal sectional view of FIG. 9 and a partially enlarged view thereof. As shown in the figure, a receiving portion 2 is formed on the pipe end side of the joint body 1, and a male screw 3 is engraved on the outer peripheral surface side of the receiving portion 2.

On the other hand, an annular metal wedge 5, a metallic washer 6 and an annular rubber packing 7 are externally fitted and attached to the joint pipe 4 having no pipe end. The metal wedge 5 has a so-called C-ring shape in which the middle is cut, the back side is a tapered surface 8 with a downward slope toward the rear end side, and the inner peripheral surface side has a serrated uneven portion 9. Has been formed.

Further, the union nut 10 is formed with an internal thread 11 on the inner peripheral surface side of the tip, and the inner surface side of the through hole at the bottom is a tapered surface 12 that abuts the tapered surface 8 of the metal wedge 5. ing.

In the conventional pipe joint thus constructed, when the union nut 10 is tightened, the metal wedge 5
Further, the rubber packing 7 advances through the washer 6 and comes into contact with the receiving portion 2 of the joint body 1 and also comes into contact with the outer peripheral surface of the joint pipe 4. As the tightening of the union nut 10 progresses, the tapered surface 8 of the metal wedge 5 is pressed by the tapered surface 12 formed on the inner peripheral surface of the through hole, and the metal wedge 5
The sawtooth-shaped uneven portion 9 bites into the outer peripheral surface of the joint pipe 4. As a result, a strong pull-out resistance can be obtained, and the joining pipe 4 can be prevented from coming off.

Moreover, when the joining pipe 4 moves so as to deviate from the joint body 1 (movement to the left in FIGS. 9 and 10 relative to the joint body 1), the tapered surface of the metal wedge 5 is formed. 8 is pressed downward by the tapered surface 12 of the union nut 10, and the metal wedge 5 further digs into the outer peripheral surface of the joint pipe 4 to prevent deviation.

As described above, in the conventional pipe joint using the union nut 10, the withdrawal force of the joint pipe 4 is improved by using the metal wedge 5 in which the annular part is cut, and It is designed to prevent leakage of flowing fluid.

[0010]

However, in the fastening operation with the union nut 10, the tapered surface 12 of the union nut 10 strongly presses the tapered surface 8 of the metal wedge 5,
At the same time that the wedge 5 bites into the joint pipe 4, the joint pipe 4 is advanced, and as a result, the rubber packing 7 is pressed to secure a predetermined sealing property. Therefore, the rotation of the union nut 10 causes the plating of the tapered surface 8 of the metal wedge 5 to peel off, and abnormal corrosion of the metal wedge 5 progresses from this portion. If there is such abnormal corrosion, the metal wedge 5 is likely to be displaced in the axial direction, the force pressing the rubber packing 7 is reduced, and a seal failure is caused.

Further, as shown in FIG. 10, the step portion 1 cut into the metal wedge 5 is rotated by the rotation of the union nut 10 when it is fastened.
3 is formed, and when the pulling force to the left in the figure acts on the joint pipe 4, the tapered surfaces 8 and 12 between the union nut 10 and the metal wedge 5 do not slip, and the wedge 5 There was a drawback that the pressing force in the diameter reducing direction was not generated. In other words, the holding force of the joining pipe 4 may be reduced, and the joining pipe 4 may easily come off.

Further, since the joint body 1, the union nut 10, the wedge 5 and the joint pipe 4 are mechanically connected and coupled, respectively, these members are integrally locked by an excessive tightening torque. However, there is also a drawback that the expansion and contraction flexibility is lost and the vibration and strain of the pipe cannot be absorbed.

Furthermore, in the final stage of tightening,
Even if the union nut 10 is tightened, the joint pipe 4 may be tightened when the tips of the joint pipe 4 are in contact with each other in the joint body 1 or when the movement of the joint pipe 4 is restricted by the stopper member in the joint body. However, since the rubber packing 7 does not move forward, the rubber packing 7 may not be pressed and sufficient sealing properties may not be ensured.

As a countermeasure against the case where the wedge 5 does not move forward as described above, it is carried out while striking the rear end side of the metal wedge 5 using a screwdriver, a hammer or the like, but it is a complicated work. Yes, it was not preferable.

[0015]

DISCLOSURE OF THE INVENTION The present invention has been made by improving and removing the conventional problem in view of the above-mentioned problems, and it is a pipe joint which can secure a sufficient sealing property and pull-out resistance only by hand tightening. And the provision of rubber packing.

The first means adopted by the present invention in order to solve the above-mentioned problems is to provide a threaded joint pipe on a pipe or a joint body having a receiving portion with an external thread engraved on its outer peripheral surface. Insert the annular rubber packing to insert and insert the union nut into the receiving part by screwing and tightening the union nut so that the inner bottom surface of the union nut and the back side of the rubber packing face rearward, respectively. Taper surface with a downward slope, and metal wedges are integrally connected to multiple points on the inner peripheral surface corresponding to the outer peripheral surface of the joint pipe of the rubber packing, and self-lubricating between the rubber packing and the union nut. A pipe joint characterized in that a sheet member made of an excellent synthetic resin material is interposed.

In the second means adopted by the present invention, instead of the sheet member of the first means, one or both of the contact surfaces of the rubber packing and the union nut has a small sliding friction resistance, It is coated with a synthetic resin material such as Teflon that is slippery.

Further, the third means adopted by the present invention is to insert a threadless joint pipe into a pipe having a receiving portion or a joint body, insert a ring-shaped rubber packing and insert it, and insert a pressing ring into a bolt and a bolt. In a pipe joint having a structure in which it is tightened to a pipe or a joint body with a nut, the inner bottom surface of the push ring and the back surface side of the rubber packing are tapered surfaces with a downward slope toward the rear side, respectively,
A sheet member made of a synthetic resin material excellent in self-lubricating property between the rubber packing and the push ring by integrally combining metal wedges at a plurality of locations on the inner peripheral surface corresponding to the outer peripheral surface of the joining tube of the rubber packing. It is a pipe joint characterized by interposing.

Further, in the fourth means adopted by the present invention, in place of the sheet member of the second means, one or both of the contact surfaces of the rubber packing and the push ring has a small sliding friction resistance, It is coated with a synthetic resin material such as Teflon that is slippery.

Further, a fifth means adopted by the present invention is an annular rubber packing used when a threadless joint pipe is inserted into a pipe having a receiving portion or a joint body and fastened with a push ring or a union nut. In the above, the rubber packing is characterized in that metal wedges are embedded at a plurality of positions on the inner peripheral surface side corresponding to the outer peripheral surface of the joining tube of the rubber packing.

[0021]

In the pipe joint of the first means of the present invention, as shown in FIG.
As shown in the embodiment of FIG. 3, an annular rubber packing 16 in which metal wedges 19 are integrally coupled to a plurality of locations on the inner peripheral surface side.
A sheet member 23 made of a synthetic resin such as Teflon having excellent self-lubricating property is interposed between the union nut 14 and the inner peripheral surface of the union nut 14. The seat member 23 effectively transmits the tightening torque of the union nut 14 to the rubber packing 16 without reducing the tightening torque by the frictional force between the union nut 14 and the rubber packing 16, and is a manual tightening of the worker. In addition, a sufficient sealing function and pullout resistance are obtained.

Further, when the joining pipe 4 moves so as to deviate, a strong force is applied to the rubber packing 16 toward the joining pipe 4 by the tapered surface 15 of the union nut 14 and the tapered surface 17 of the annular rubber packing 16. The metal wedge 19 embedded in the annular rubber packing 16 is strongly pressed into the joint pipe 4 to prevent deviation.

The pipe fitting of the third means of the present invention is, as shown in the embodiment of FIG. 4, the union nut 1 of the first means.
4 is replaced with a push ring 24, and the basic operation is the same as that of the first means. In addition, the second and fourth means of the present invention, in place of the seat member 23 of the first and third means, on either or both of the contact surfaces of the union nut 14 or the push ring 24 and the rubber packing 16. , Teflon or other synthetic resin material is coated, and the basic operation is the same in this case as well.

Rubber packing 16 of the fifth means of the present invention
As shown in the embodiments of FIGS. 1 to 8, metal wedges 19 are embedded and provided at a plurality of positions on the inner peripheral surface side, and are integrally connected to a rubber material. Wedge member 19
Is to be completely embedded in the rubber packing 16 or to be bonded with an adhesive after the rubber packing 16 is manufactured, and since the wedge member 19 is not separated independently from the rubber packing, the construction work can be performed. It is extremely convenient. Further, the wedge member 19 does not mix into the joint pipe 4 and the joint body 1 during the construction.

On the surface of the metal wedge 19 on the joint pipe 4 side,
Biting teeth 29 projecting at predetermined intervals in the axial direction are provided in the same direction as the outer peripheral surface direction of the joint pipe 4. By thus disposing the biting teeth 29 in a distributed manner, the wedge 19
The pressing force can be intensively transmitted to the joint pipe 4, and as a result, a strong fastening force can be obtained.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below with reference to the embodiments shown in the drawings. The same reference numerals as in the conventional case are the same members. 1 to 3 relate to an embodiment of the first invention, FIG. 1 is a vertical sectional view of a pipe joint showing a state before fastening, and FIG. 2 is a vertical sectional view of a pipe joint showing a state after fastening. FIG. 3 and FIG. 3 are vertical cross-sectional views when a pulling force acts on the joint pipe.

As shown in FIGS. 1 to 3, the union nut 14 according to this embodiment has an inner bottom surface formed into a tapered surface 15 which is downwardly sloped rearward (to the left in FIG. 1).
Further, as shown in FIGS. 1 to 3, an annular rubber packing 16
Is formed on the taper surface 17 of which the back side is downwardly inclined rearward (to the left in FIGS. 1 to 3), and the receiving portion 2 of the joint body 1 is formed.
The portion to be joined with the tapered surface is formed on the tapered surface 18 having a downward slope toward the tip side (right direction in FIGS. 1 and 2).

Further, metal wedges 19 are integrally embedded in a plurality of locations on the circumference of the rubber packing 16 on the inner peripheral surface side at equal positions. As the embedding method, the rubber packing 16 may be integrally joined at the time of manufacturing, or the rubber packing 16
After manufacturing, it may be embedded and bonded separately.

Further, between the outer peripheral surface side of the rubber packing 16 and the inner peripheral surface side of the union nut 14, a seat member 23 made of synthetic resin having excellent self-lubricating property is fitted. There is. Teflon is most suitable for the sheet member 23.

The inner diameter of the annular rubber packing 16 is larger than the outer diameter of the threadless joint pipe 4 by a dimension t = 0.3-.
The size is set to be large by 0.5 mm so that the attachment work to the joining pipe 4 can be easily performed. Further, the outer diameter C of the tip of the metal wedge 19 of the rubber packing 16 in FIGS.
Is set to be smaller than the inner diameter D of the bottom of the union nut 14 when the union nut 14 is tightened to reduce its diameter.

This dimensional relationship is such that when a force in the direction of departure is applied to the joining pipe 4, a part of the metal wedge 19 enters the bottom of the union nut 14 together with the rubber packing 16 to make the metal. Applying a force in the diameter reducing direction to the wedge 19,
This is for improving the tightening holding force of the joint pipe 4.
The area where the metal wedge 19 enters the bottom of the union nut 14 is sufficient from the left end side to a location of 1/4 to 1/2, and thus the thickness and the taper angle of the metal wedge 19 are large. It is set.

Next, an operation mode in the case where a pipe joint is constructed by using each member constructed as described above will be described. First,
The union nut 14, the sheet member 23, and the rubber packing 16 are externally fitted and mounted on the outer peripheral surface of the distal end of the joining pipe 4 in this order. Then, the female screw 11 of the union nut 14 is screwed into the male screw 3 of the joint body 1, and as shown in FIG. 1, tightening by hand is started.

The tightening force of the union nut 14 advances the rubber packing 16 through the synthetic resin sheet member 23 having excellent self-lubricating property (moves to the right in FIGS. 1 to 3).
Let Then, in the rubber packing 16, the taper surface 18 at the tip abuts on the receiving portion 2 of the joint body 1, and thereafter, the rubber packing 16 receives a stress in the diameter reducing direction as shown in FIG.
The inner peripheral surface thereof comes into strong contact with the joint pipe 4, and the rubber packing 16 secures a sufficient sealing property between the receiving portion 2 of the joint body 1 and the joint pipe 4.

In this case, the synthetic resin sheet member 23
Prevents the direct contact between the union nut 14 and the rubber packing 16 and significantly reduces the frictional force on the back surface side of the rubber packing 16 to reduce the tightening torque of the union nut 14 without reducing the rubber packing 16
I try to make it effectively transmitted to.

As a result, the receiving portion 2 of the rubber packing 16
Also, it is possible to increase the frictional force on the joint pipe 4 and to exert a sufficient sealing function. As described above, the seat member 23 having excellent self-lubricating property is provided between the union nut 14 and the rubber packing 16 to reduce the frictional force between them, so that a sufficient seal can be obtained even by hand tightening. It is possible to exert the function, and the work of constructing the pipe joint becomes extremely easy.

Further, the union nut 1 is attached to the rubber backing 16.
Since the tightening torque by 4 is effectively transmitted, the metal wedge 19 integrally connected to the rubber packing 16 bites into the outer peripheral surface of the joining pipe 4 with sufficient force, and has a function of holding it tightly. .

Next, the case where the joint pipe 4 moves to deviate from the joint body 1 from such a state is shown in FIG.
Will be described with reference to. In this case, the joint pipe 4 is the joint body 1
On the other hand, it tries to move relatively to the left side of FIG.
However, when such joining pipe 4 moves, the rubber packing 16 is tapered to the inner peripheral surface of the union nut 14 mechanically integrated with the joint body 1.
Reduce the diameter to the left in the figure through the rubber packing 16
Increase the compression force of.

Therefore, the rubber packing 16 receives a stress in the diameter reducing direction, the metal wedge 19 further digs into the joint pipe 4, and functions to prevent the joint pipe 4 from deviating. Also in this case, the synthetic resin sheet member 2 having excellent self-lubricating property
No. 3 prevents the rubber packing 16 and the union nut 14 from directly contacting each other, and remarkably reduces the frictional force on the back surface side of the rubber packing 16, so that the movement of the rubber packing 16 in the radial direction is reduced. The joint pipe 4 is converted into the joint pipe 4 with a strong force to prevent the joint pipe 4 from deviating.

In the second means of the present invention, instead of the sheet member 23 of the first means, a synthetic resin material such as Teflon which has the same function (less sliding friction resistance and is slippery) is used.
Inner peripheral surface side of union nut 14 or rubber packing 1
The outer peripheral surface of 6 or both of them are coated.

Next, an embodiment of the third means of the present invention will be described with reference to FIG. As shown in the figure, in this embodiment, instead of the union nut 14 of the first means,
The push ring 24 is used. This push ring 24
Is fastened to the flange 27 of the joint body 1 using the bolt 25 and the nut 26. Fastening with the bolt 25, the nut 26, and the flange 27 is performed at a plurality of positions in the entire circumferential direction.

In the embodiment of the third means, with the seat member 23 and the annular rubber packing 16 fitted in the push ring 24, the push ring 24 is temporarily fixed to the joint body 1 first. After that, the workability is better when the joining pipe 4 is inserted through the push ring 24 and the rubber packing 16 and then inserted into the socket 2 of the joint body 1.

Therefore, if the push ring 24 is tightly fitted to the joint body 1 side before the joining pipe 4 is inserted, the rubber packing 16 is reduced in diameter, which makes it difficult to insert the joining pipe 4. Therefore, in this embodiment, the temporary fixing member 28 made of hard vinyl chloride is mounted between the push ring 24 and the outer peripheral surface of the receiving portion 2 of the joint body 1. This temporary fixing member 2
When the final tightening is performed, No. 8 is stretched flat and intervenes in that state, and does not hinder the final tightening. The other constitutions and effects are the same as in the case of the above-mentioned first embodiment of the invention.

In the fourth means of the present invention, the sheet member 23 of the third means is omitted, and instead, a synthetic resin material such as Teflon which has the same function (less sliding friction resistance and is slippery) is used. The inner peripheral surface side of 24, the outer peripheral surface side of the rubber packing 16, or both of them are covered.

Next, an embodiment of the fifth means of the present invention will be described with reference to FIGS. In this example,
As shown in FIGS. 5, 7 and 8, biting teeth 29 of the joining pipe 4 are formed on the inner peripheral surface side of the metal wedge 19 embedded in the annular rubber packing 16 at predetermined intervals in the pipe axial direction. It is dispersed by projecting in the same direction as the outer peripheral surface direction. In this way, by making the engaging teeth 29 disperse and project, a space 21 (see FIG. 5) is formed between the surface of the rubber material thinly coated on the inner peripheral surface side of the metal wedge 19 and the joint pipe 4. Can be formed. This space 21 has a biting tooth 29.
This is for ensuring a bite into the joint pipe 4 and for concentrating the elastic compression force generated in the rubber packing 16 on the bite teeth 29.

Further, by distributing the biting teeth 29, it is possible to concentrate the stress acting on the metal wedges 19 on these distributed biting teeth 29. Therefore, due to the space 21 and the distributed biting teeth 29, the reducing force acting on the rubber packing 16 is concentrated on the biting teeth 29, and the biting teeth 29 are connected to each other within the range of the space 21. 4 will be bitten by a stronger force, and as a result, a strong tightening holding force for preventing deviation of the joint pipe 4 will be obtained.

As shown in FIG. 6, the biting teeth 29 are manufactured by an annular split mold composed of left and right rubber molds 30 and 31 and a core mold 32. By providing the convex portion 33 that comes into contact with the concave portion between the biting teeth 29 of the metal wedge 19, the biting teeth 2 at the time of manufacturing
9 and the core die 32 do not come into contact with each other, and the life of the molding die can be extended.

By the way, the present invention is not limited to the above-mentioned embodiment, and, for example, three metal wedges 19 are arranged on the inner peripheral surface side of the rubber packing 16 at equal positions on the circumference. Although the case has been described, there may be a plurality of other cases. The number of installations depends on the size of the joint pipe 4 and the metal wedge 1.
It may be determined according to the size of 9 or the like.

Further, the metal wedge 19 and the rubber packing 16
As a matter of course, in addition to the case of integrally molding in advance in a factory or the like, the metal wedges 19 may be integrally combined using an adhesive after the rubber packing 16 is manufactured.

[0049]

As described above, in the first and second means of the present invention, metal wedges are integrally connected to at least a plurality of locations on the inner peripheral surface side of the annular rubber packing, and the rubber packing back surface is formed. Since a seat member made of synthetic resin with excellent self-lubricating property is placed between the taper surface on the side and the taper surface side of the union nut or the push ring, the tightening torque of the union nut or the push ring can be adjusted with the union nut or the push ring. The rubber packing can be effectively transmitted to the rubber packing without being reduced by the frictional force between the packing and the rubber packing, and the rubber packing can be reduced in diameter. Can be demonstrated.

Since the rubber packing is interposed,
The union nut or the push ring and the metal wedge never become in a mechanically locked state, and even when a force in the deviating direction acts on the joint pipe, the expansion and contraction flexibility is always impaired. It is possible to provide an excellent pipe joint of this type.

Further, in the final stage of tightening, even if the tips of the joint pipes are in contact with each other in the joint body or the movement of the joint pipe is restricted by the stopper member in the joint body, Due to the elastic force of the rubber packing, it is possible to further tighten the union nut or the push ring. In this case, the elastic compression force of the rubber packing becomes even stronger, and the metal wedge can hold the joint pipe tightly. In addition, the rubber packing can ensure excellent water tightness.

Furthermore, in the past, if rust-preventing oil, oil for thread cutting, etc. adhered on the pipe, the force for holding the joint pipe would be extremely reduced, and the joint pipe could be reliably removed. It was extremely difficult to prevent, but in the present invention, even when these oils are present, the metal wedge bites into the joint pipe,
It is possible to reliably prevent the deviation.

Further, when the joining pipe moves so as to deviate, the rubber packing is prevented from directly contacting the union nut or the push ring with the synthetic resin sheet member, and the frictional force on the back side of the rubber packing is reduced. By doing so, a large compressive force is generated in the rubber packing, and as a result, it is possible to reduce the diameter of the rubber packing and cause the metal wedge to bite strongly into the joint pipe and prevent the deviation.

On the other hand, in the rubber packing of the fifth means of the present invention, metal wedges are embedded in a plurality of positions on the inner peripheral surface side and integrally joined to the rubber material, and the wedge member and the rubber packing. Construction work is extremely convenient because it does not separate independently. In addition, the wedge member does not mix into the joint pipe and the joint body during construction. In addition, since the metal wedge is not exposed, it does not cause abnormal corrosion.

Further, on the surface of the metal wedge on the side of the joint pipe, biting teeth are provided at predetermined intervals in the axial direction, whereby a space for securing a biting margin with the joint pipe is provided. Can be formed, and the pressing force of the wedge can be centrally transmitted to the joint pipe, resulting in a strong fastening force.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a state before fastening of a pipe joint according to a first means of the present invention.

FIG. 2 is a vertical cross-sectional view showing a state after fastening of the pipe joint according to the first means of the present invention.

FIG. 3 is a vertical cross-sectional view showing a case where a force in a departure direction is applied to the pipe joint according to the first means of the present invention.

FIG. 4 is a vertical sectional view of a pipe joint according to a third means of the present invention.

FIG. 5 is a vertical sectional view showing a pipe joint according to a fifth means of the present invention.

FIG. 6 is a partial vertical cross-sectional view showing a molding die for rubber packing according to a fifth means of the present invention.

FIG. 7 is a front view of a rubber packing according to a fifth means of the present invention.

FIG. 8 is a vertical sectional side view of a rubber packing according to a fifth means of the present invention.

FIG. 9 is a semi-longitudinal sectional view showing a conventional pipe joint.

FIG. 10 is a partially enlarged view of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Joint main body 2 ... Receptacle part 3 ... Male screw 4 ... Junction pipe 11 ... Female screw 14 ... Union nut 15 ... Union nut taper surface 16 ... Rubber packing 17 ... Tapered surface on the back side of rubber packing 18 ... Tip of rubber packing Side tapered surface 19 ... Metal wedge 20 ... Synthetic resin sheet member

Claims (7)

[Claims] 1. A pipe having a socket having an external thread engraved on the outer peripheral surface thereof, or a joint body, into which a threadless joint pipe is inserted, and an annular rubber packing is inserted and inserted to insert the union nut into the socket. In a pipe joint with a structure that is screwed and tightened, the inner bottom surface of the union nut and the back surface side of the rubber packing are tapered toward the rear side, and the inner circumference corresponding to the outer peripheral surface of the joint tube of the rubber packing. A pipe joint characterized in that metal wedges are integrally connected to a plurality of positions on the surface, and a sheet member made of a synthetic resin material having excellent self-lubricating property is interposed between the rubber packing and the union nut. . 2. A pipe having a socket having an external thread engraved on its outer peripheral surface or a joint body is inserted into a joint pipe having no thread, and a ring-shaped rubber packing is inserted and inserted to insert the union nut into the socket. In a pipe joint with a structure that is screwed and tightened, the inner bottom surface of the union nut and the back surface side of the rubber packing are tapered toward the rear side, and the inner circumference corresponding to the outer peripheral surface of the joint tube of the rubber packing. Metal wedges are integrally connected to a plurality of points on the surface, and one or both of the contact surfaces of the rubber packing and the union nut are coated with a synthetic resin material such as Teflon that has low sliding friction resistance and is slippery. A pipe joint characterized by the following. 3. A structure having a structure in which a threadless joint pipe is inserted into a pipe or a joint body having a receiving portion, an annular rubber packing is inserted and fitted, and a push ring is tightened to the pipe or the joint body with bolts and nuts. In the pipe joint, the inner bottom surface of the push ring and the back surface side of the rubber packing are tapered surfaces that are inclined downward toward the rear side, respectively, and the metal packing is provided at a plurality of locations on the inner peripheral surface corresponding to the outer peripheral surface of the joining tube of the rubber packing. A pipe joint in which a wedge is integrally connected, and a sheet member made of a synthetic resin material having excellent self-lubricating property is interposed between the rubber packing and the push ring. 4. A structure having a structure in which a threadless joint pipe is inserted into a pipe or a joint body having a receiving portion, an annular rubber packing is inserted and inserted, and a push ring is tightened to the pipe or the joint body with bolts and nuts. In the pipe joint, the inner bottom surface of the push ring and the back surface side of the rubber packing are tapered surfaces that are inclined downward toward the rear side, respectively, and the metal packing is provided at a plurality of locations on the inner peripheral surface corresponding to the outer peripheral surface of the joining tube of the rubber packing. A pipe joint in which a wedge is integrally connected, and one or both of the contact surfaces of the rubber packing and the push ring is coated with a synthetic resin material such as Teflon which has low sliding friction resistance and is slippery. 5. A ring-shaped rubber packing used when a threadless joint pipe is inserted into a pipe having a socket or a joint body and fastened with a push ring or a union nut, the outer periphery of the joint pipe of the rubber packing. A rubber packing in which metal wedges are embedded at a plurality of positions on the inner peripheral surface side corresponding to the surface. 6. The pipe joint according to claim 1, wherein biting teeth in the same direction as the circumferential direction of the joint pipe project from the inner peripheral surface of the metal wedge. Or rubber packing. 7. The pipe joint or the rubber packing according to claim 6, wherein a plurality of biting teeth are provided side by side.