JP2000154892A - Pipe fitting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe fitting having a retainer fixed with a gasket, capable of preventing a tightening member or a pipe from being scratched by the retainer and preventing an energizing claw part for mounting on the tightening member or the pipe from being deformed due to external force when a fitting main body is removed from the tightening member in maintenance. SOLUTION: A gasket 19 is fixed on a retainer 18 by spot-welding on a face of the gasket 19 on a side where the retainer 18 is mounted on a pipe 11. Moreover, the retainer 18 is mounted on the pipe 11 by an energizing claw part provided on the retainer 18. Such energizing claw part is molded integrally with a cylindrical protection part provided on the retainer 18 and exists in an outer peripheral face of the protection part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint used for a gas line for semiconductors.

[0002]

2. Description of the Related Art Conventionally, a pipe joint 100 as shown in FIGS. 6 and 7 has been used in a semiconductor gas piping line in a semiconductor manufacturing apparatus. Here, the pipe joint 100 shown in FIGS. 6 and 7 will be described. The outer ferrule 1 which is a thrust bearing is provided on the pipe 101.
04 is inserted. Further, an inner ferrule 103 is attached to the pipe 101. The inner ferrule 103 engages with a groove formed on the outer periphery of the pipe 101 and fits the pipe 101 and the outer ferrule 104 together.

Therefore, even if the joint body 105 is screwed into the tightening member 106 while rotating, the inside of the joint body 105 presses the outer ferrule 104,
Can transfer the inside of the joint body 105 without rotation. At this time, since the inner ferrule 103 has a wedge shape, the fitting between the pipe 101 and the outer ferrule 104 can be ensured.

When the joint body 105 is tightened to the tightening member 106, the pipe 101 moving inside the joint body 105 in a non-rotating state moves the gasket 109 held by the pipe 101 via a retainer 108. , Crushed.

Thus, the pipe joint 100 shown in FIGS. 6 and 7 can connect the flow path 107 of the tightening member 106 to the flow path 102 of the pipe 101. In addition, since the gasket 109 is sandwiched between the pipe 101 and the fastening member 106 at the connection surface between the flow paths 102 and 107, leakage from the connection surface between the flow paths 102 and 107 can be prevented.

[0006]

However, a retainer 108 for holding the gasket 109 on the pipe 101 is required.
In FIG. 8, as shown in FIGS.
Since the gasket 109 is fixed to the retainer 108 by bending A, the grip portion 108A of the retainer 108 is in a state of protruding from the surface of the gasket 109. Then, for maintenance or the like, the fastening member 1
When the joint body 105 is detached from the gasket 106, the retainer 10 protrudes from the surface of the gasket 109.
8 will be exposed to the outside.
There is a possibility that the fastening member 106 and the like may be damaged.

[0008] As shown in FIGS. 8 and 9, the urging claw 10 for attaching the retainer 108 to the pipe 101 is used.
8B has no thickness in order to generate an urging force due to bowing, and is provided in a state protruding from the retainer 108, and thus may be deformed by external force.

Accordingly, the present invention has been made to solve the above-mentioned problems, and has been developed in such a manner as maintenance.
An object of the present invention is to provide a pipe joint in which a retainer to which a gasket is fixed does not damage a tightening member or a pipe when a joint body is removed from the tightening member. Also,
An object of the present invention is to provide a pipe joint having a retainer that prevents a biasing claw portion for mounting on a fastening member or a pipe from being deformed by an external force.

[0009]

According to a first aspect of the present invention, there is provided a pipe joint, wherein the joint body is screwed into a fastening member so that the inside of the joint body is kept in a non-rotating state. Along with connecting the flow path of the tightening member to the flow path of the pipe moving in, a gasket held by the tightening member or the pipe via a retainer mounted on the tightening member or the pipe, A pipe joint for preventing leakage from the connection surface of the flow channel by being sandwiched by the connection surface of the flow channel, wherein the gasket is fixed to the retainer on an outer periphery or a surface on the mounting side of the retainer. It is characterized by being.

[0010] Further, the pipe joint according to claim 2 is characterized by claim 1.
Wherein the gasket is welded,
It is characterized in that it is fixed to the retainer by any one of bonding and caulking.

[0011] Further, the pipe joint according to claim 3 is characterized by claim 1.
Alternatively, the pipe joint according to claim 2, wherein the flow path of the pipe and the flow path of the fastening member are connected to another flow path by another pipe joint. A pipe joint according to claim 4 is the pipe joint according to claim 1 or 2, wherein the flow path of the pipe and the flow path of the fastening member are connected to another flow path by welding. It is characterized by that.

[0012] Further, the pipe joint according to claim 5 is characterized by claim 1.
5. The pipe joint according to claim 4, wherein the pipe or the fastening member is a connection joint. The pipe joint according to claim 6 is:
The pipe joint according to any one of claims 1 to 4, wherein the pipe or the fastening member is a connection port of a fluid device.

[0013] Further, the pipe joint according to claim 7 is provided in claim 1.
The pipe joint according to any one of claims 4 to 4, wherein the pipe joint is used for connecting flow paths of respective fluid devices fixed at respective mounting positions.

In the pipe joint according to the eighth aspect, the joint body is screwed into the fastening member to connect the flow paths of the two pipes that move inside the joint body without rotating. Through a retainer mounted on one of the pipes, a gasket held on one of the pipes,
A pipe joint for preventing leakage from the connection surface of the flow channel by being sandwiched by the connection surface of the flow channel, wherein the gasket is fixed to the retainer on an outer periphery or a surface on the mounting side of the retainer. It is characterized by being.

Further, the pipe joint according to claim 9 is the same as claim 8.
Wherein the gasket is welded,
It is characterized in that it is fixed to the retainer by any one of bonding and caulking.

A pipe joint according to a tenth aspect is the pipe joint according to the eighth or ninth aspect, wherein a flow path of the pipe is connected to another flow path by another pipe joint. It is characterized by. An eleventh aspect of the present invention is the pipe joint according to the eighth or ninth aspect, wherein a flow path of the pipe is connected to another flow path by welding.

According to a twelfth aspect of the present invention, there is provided a pipe joint according to any one of the eighth to eleventh aspects, wherein one of the pipes is a connection joint. A pipe joint according to a thirteenth aspect is the pipe joint according to any one of the eighth to eleventh aspects, wherein one of the pipes is a connection port of a fluid device.

According to a fourteenth aspect of the present invention, there is provided the pipe joint according to any one of the eighth to eleventh aspects, wherein the flow path of each fluid device fixed to each mounting position is provided. It is characterized by being used to connect.

In the pipe joint according to a fifteenth aspect, by screwing the joint body to the tightening member, the joint member of the pipe moves in a non-rotating state inside the joint body. A gasket held by the tightening member or the pipe is held by the connecting surface of the flow channel via a retainer attached to the tightening member or the pipe with a biasing claw while connecting the flow paths. A pipe joint for preventing leakage from the connecting surface of the flow path,
The retainer is provided with a protection portion having the biasing claw therein.

The pipe joint according to claim 16 is the pipe joint according to claim 15, wherein the flow path of the pipe and the flow path of the tightening member are formed by another flow path and another pipe joint. It is characterized by being connected. A pipe joint according to claim 17 is the pipe joint according to claim 15, wherein the flow path of the pipe and the flow path of the fastening member are connected to another flow path by welding. And

A pipe joint according to claim 18 is the pipe joint according to any one of claims 15 to 17, wherein the pipe or the fastening member is a connection joint. And A pipe joint according to claim 19 is the pipe joint according to any one of claims 15 to 17, wherein the pipe or the tightening member is a connection port of a fluid device. And

According to a twentieth aspect of the present invention, the joint body is screwed with the fastening member to connect the flow paths of the two pipes moving inside the joint body without rotating. By interposing a gasket held on one side of the pipe by a connecting surface of the flow path via a retainer mounted on one side of the pipe with an urging claw portion, leakage from the connecting surface of the flow path can be prevented. A pipe joint for preventing, wherein a protection portion in which the urging claw portion is provided is provided on the retainer.

The pipe joint according to claim 21 is the pipe joint according to claim 20, wherein the flow path of the pipe is connected to another flow path by another pipe joint. . A pipe joint according to a twenty-second aspect is the pipe joint according to the twentieth aspect, wherein a flow path of the pipe is connected to another flow path by welding.

[0024] A pipe joint according to claim 23 is the pipe joint according to any one of claims 20 to 23, wherein one of the pipes is a connection joint. A pipe joint according to claim 24 is the pipe joint according to any one of claims 20 to 23, wherein one of the pipes is a connection port of a fluid device.

According to a twenty-fifth aspect of the present invention, there is provided a pipe joint according to any one of the first to twenty-fourth aspects, wherein the pipe joint is used in a semiconductor gas piping line. .

[0026] The pipe joint of the present invention having such specific items is provided by screwing the joint body to the tightening member.
The flow path of the tightening member is connected to the flow path of the pipe that moves inside the joint body without rotating. Alternatively, the joint body is screwed into the fastening member to connect the flow paths of the two pipes that move inside the joint body without rotating.

In these, the gasket is sandwiched between the connecting surfaces of the flow paths in order to prevent leakage from the connecting surfaces of the flow paths. Such a gasket is held by a fastening member or a pipe via a retainer attached to the fastening member or the pipe.

The gasket is fixed to the retainer on the outer periphery of the gasket or on the surface of the gasket where the retainer is mounted. Therefore, there is nothing that protrudes from the surface of the gasket, such as the gripper of the retainer of the prior art. Therefore, even if the joint body is removed from the fastening member for maintenance or the like, the retainer to which the gasket is fixed does not damage the fastening member or the pipe.

The retainer is attached to a tightening member or a pipe with a biasing claw provided on the retainer.
Such an urging claw portion is provided inside a protection portion provided on the retainer. Therefore, the urging claw for mounting the retainer on the tightening member or the pipe, even if it is not thick enough to generate the urging force due to buckling, does not protrude from the protection part of the retainer. There is no deformation due to external force.

That is, in the pipe joint of the present invention, there is no gasket in which the gasket is fixed to the retainer on the outer periphery of the gasket or on the surface of the gasket on which the retainer is mounted, and projects from the gasket surface. Therefore, when the joint body is removed from the fastening member for maintenance or the like, the fastening member or the pipe is not damaged by the retainer to which the gasket is fixed.

In particular, when the pipe joint of the present invention is used to connect the flow paths of the respective fluid devices fixed at the respective mounting positions, there is something that protrudes from the surface of the gasket. In order to secure a moving space to avoid being hurt by something that protrudes from the surface of the gasket when removing the joint body from the tightening member and taking out the fluid device for maintenance, etc. It is not necessary to perform an operation of releasing the fixing of the mounting position of the other fluid device, and it is only necessary to release the fixing of the mounting position of only the fluid device.

The urging claw for mounting the retainer on the tightening member or the pipe is provided inside the protective portion provided on the retainer, and is in a state protruding from the protective portion provided on the retainer. It is not deformed by external force.

[0033]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is an exploded view of the pipe joint 10 of the present embodiment. Pipe fitting 10 of the present embodiment
Is a flow passage 12 (see FIG. 1) of a pipe 11 and a fastening member 16.
Of the inner ferrule 13, a wedge-shaped inner ferrule 13, an outer ferrule 14, which is a thrust bearing, a joint body 15, and a tightening member 1.
6, a retainer 18, a metal gasket 19, and the like.

FIG. 1 shows a pipe joint 10 according to the present embodiment.
FIG. In the pipe joint 10 of the present embodiment, the outer ferrule 14 is inserted into the pipe 11. Further, the pipe 11 has an inner ferrule 13.
Is installed. The inner ferrule 13 is
While engaging with the groove formed in the outer periphery of the pipe 11,
The pipe 11 and the outer ferrule 14 are fitted together.

Therefore, even if the joint body 15 is screwed into the tightening member 16 while rotating, and the inside of the joint body 15 presses the outer ferrule 14, the pipe 11 keeps the inside of the joint body 12 in a non-rotating state. Can be relocated. At this time, since the inner ferrule 13 has a wedge shape, the fitting between the pipe 11 and the outer ferrule 14 can be ensured.

Then, the joint body 1 is
When the joint 5 is tightened, the pipe 11 that moves inside the joint body 15 in a non-rotating state causes the gasket 19 held on the pipe 11 via the retainer 18 to be in a crushed state.

As a result, the pipe joint 10 shown in FIG. 1 and FIG.
Channel 17 can be connected. In addition, channel 1
Since the gasket 19 is sandwiched between the pipe 11 and the fastening member 16 at the connection surfaces 2 and 17, leakage from the connection surfaces of the flow paths 12 and 17 can be prevented.

In FIG. 1, the gasket 19 is
While being held by the pipe 11 via the retainer 18,
In FIG. 2, the gasket 19 is held by the fastening member 16 via the retainer 18, but may be held by either.

Here, the pipe joint 10 shown in FIGS.
, The retainer 18 to which the gasket 19 is fixed will be described. FIG. 4 is a front view of the retainer 18 to which the gasket 19 is fixed. FIG. 3 shows a retainer 18 to which a gasket 19 is fixed, which is cut by a dashed line in FIG.
FIG.

As shown in FIGS. 3 and 4, the gasket 1
9 is fixed to the retainer 18 by spot welding 20 (see FIG. 4) on the surface of the gasket 19 on the mounting side of the retainer 18. Specifically, in the pipe joint 10 shown in FIG.
The surface of the gasket 19 on the side mounted on 1 is fixed to the retainer 18. In the pipe joint 10 shown in FIG. 2, the gasket 19 is such that the retainer 18 is
The surface of the gasket 19 on the side mounted on 6 is fixed to the retainer 18.

Therefore, as shown in the section of the prior art, like the grip portion 108A of the retainer 108 shown in FIGS. 8 and 9, the one that protrudes from the surface of the gasket 19 is the pipe joint 10 of the present embodiment. Does not exist at all. Therefore, in the pipe joint 10 shown in FIG. 1, the retainer 18 to which the gasket 19 is fixed does not damage the pipe 11 even when the joint body 15 is removed from the fastening member 16 for maintenance or the like. Also, the pipe joint 1 shown in FIG.
At 0, even if the joint body 15 is removed from the fastening member 16 for maintenance or the like, the retainer 18 to which the gasket 19 is fixed does not damage the fastening member 16.

The retainer 18 is provided with a biasing claw 18B provided on the retainer 18 so that the pipe joint 1 shown in FIG.
At 0, it is attached to the pipe 11, and in the pipe joint 10 shown in FIG.
The biasing claw portion 18B is formed integrally with a cylindrical protection portion 18C provided on the retainer 18, and is present in the outer peripheral surface of the protection portion 18C.

Therefore, the urging claw 18B for mounting the retainer 18 on the tightening member 16 or the pipe 11 is provided on the retainer 18 even if the urging claw 18B is not thick enough to generate an urging force due to bending. Since it does not protrude from the protected portion 18C, it is not deformed by external force.

That is, in the pipe joint 10 according to the present embodiment, the gasket 19 is fixed to the retainer 18 on the surface of the gasket 19 on the mounting side of the retainer 18 so as to protrude from the surface of the gasket 19. Does not exist, so that when the joint body 15 is removed from the fastening member 16 for maintenance or the like, the fastening member 16 or the pipe 11 is not damaged by the retainer 18 to which the gasket 19 is fixed.

The urging claw 18B for mounting the retainer 18 on the tightening member 16 or the pipe 11 is provided inside the protective portion 18C provided on the retainer 18, and is provided on the retainer 18. Since it is not in a state of protruding from 18C, it is not deformed by external force.

It should be noted that the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention. For example, in the pipe joint 10 of the present embodiment, the gasket 19 is fixed to the retainer 18 on the surface of the gasket 19 on the mounting side of the retainer 18. However, even if the gasket 19 is fixed to the retainer 18 on the outer periphery of the gasket 19,
When the joint body 15 is detached from the tightening member 16 for maintenance or the like, the gasket 1 may not be present at all.
9 or a pipe 1
1 can be prevented from being damaged.

In the pipe joint 10 of the present embodiment, the gasket 19 is fixed to the retainer 18 by welding, but may be fixed to the retainer 18 by bonding, caulking, or the like.

Further, in the pipe joint 10 of the present embodiment, the urging claw portion 18B provided on the retainer 18 is formed integrally with the protection portion 18C provided on the retainer 18, but the protection portion 18C Protective unit 1
8C may be separately formed and provided on the retainer 18. The shape of the protection portion 18C is cylindrical, but the urging claw 1
Any shape may be used as long as it can be protected from external force by the presence of 8B.

Further, in the pipe joint 10 of the present embodiment, the fastening member 16 is a connection joint, or
It may be a connection port of a fluid device. Also, pipe 1
1 may be a connection joint or a connection port of a fluid device.

The pipe joint 10 of the present embodiment is a so-called weldless joint, and the flow path 12 of the pipe 11 and the flow path 17 of the fastening member 16 are connected to another flow path by another pipe joint. However, as shown in a pipe joint 30 shown in FIG. 5, a so-called welded joint may be used in which the flow path 32 of the pipe 31 is connected to another flow path by welding. . Similarly, the flow path 37 of the fastening member 36 may be connected to another flow path by welding.

The pipe joint 30 shown in FIG. 5 is used for a semiconductor gas piping line, and is provided with bolts 41 and 42 fixed to respective mounting positions by bolts.
The pipe joint 30 shown in FIG. 5 is used to connect the flow passages 43 (corresponding to a fluid device). In the pipe joint 30 shown in FIG. From, for maintenance, etc.
Remove the joint body 35 from the fastening member 36, for example,
When the valve 42 is taken out, in order to secure a moving space for avoiding being damaged by an object protruding from the surface of the gasket 39, the fixing of the mounting positions of the other valves 41 and 43 is released. There is no need to perform any operation, and it is only necessary to release the fixing of the mounting position of only the valve 42.

Further, the pipe joint 10 of the present embodiment is configured such that the joint body 15 is screwed into the tightening member 16 so that the flow path 12 of the pipe 11 that moves inside the joint body 15 in a non-rotating state. Thus, the two pipes which move inside the joint main body 15 in a non-rotating state by screwing the joint main body 15 to the tightening member 16 are used. May be connected.

Further, the present invention is not limited to use in a semiconductor gas piping line, but may be used in other piping lines.

[0054]

According to the pipe joint of the present invention, there is no gasket in which the gasket is fixed to the retainer on the outer periphery of the gasket or on the side of the gasket on which the retainer is mounted, and projects from the gasket surface. Therefore, when the joint body is removed from the fastening member for maintenance or the like, the fastening member or the pipe is not damaged by the retainer to which the gasket is fixed.

In particular, when the pipe joint of the present invention is used to connect the flow paths of the respective fluid devices fixed at the respective mounting positions, there is something that protrudes from the surface of the gasket. In order to secure a moving space to avoid being hurt by something that protrudes from the surface of the gasket when removing the joint body from the tightening member and taking out the fluid device for maintenance, etc. It is not necessary to perform an operation of releasing the fixing of the mounting position of the other fluid device, and it is only necessary to release the fixing of the mounting position of only the fluid device.

The urging claw for mounting the retainer on the tightening member or the pipe is provided inside the protective portion provided on the retainer and is in a state of protruding from the protective portion provided on the retainer. It is not deformed by external force.

[Brief description of the drawings]

FIG. 1 is a view showing a cross section of a pipe joint of the present invention.

FIG. 2 is an exploded view of the pipe joint of the present invention.

FIG. 3 is a view showing a cross section of the retainer to which the gasket is fixed in the pipe joint of the present invention, taken along a dashed line in FIG. 4;

FIG. 4 is a front view of the retainer to which the gasket is fixed in the pipe joint of the present invention, as viewed from the non-attaching side.

FIG. 5 is a view showing a part of a semiconductor gas piping line in which the pipe joint of the present invention is used.

FIG. 6 is an exploded view of a conventional pipe joint.

FIG. 7 is a diagram showing a cross section of a conventional pipe joint.

FIG. 8 is a view showing a cross section of the retainer to which the gasket is fixed in the conventional pipe joint, which is cut by a dashed line in FIG. 9;

FIG. 9 is a diagram showing a front view of a retainer to which a gasket is fixed in a conventional joint, viewed from a non-attaching side.

[Explanation of symbols]

 10, 30 Pipe joint 11, 31 Pipe 12, 32 Pipe flow path 15, 35 Joint body 16, 36 Tightening member 17, 37 Tightening member flow path 18, 38 Retainer 18B Urging claw 18C Protecting part 19, 39 Gasket 41, 42, 43 Valve

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Ichinoji Koryo 850 Horinouchi-cho, Kasugai-shi, Aichi Prefecture Inside Kasugai Works (72) Inventor Naoki Ito 850 Horinouchi-machi, Kasugai-shi, Aichi Kasugai Corporation In-house F-term (reference) 3H014 DA01 DA07

Claims (25)

[Claims] A joint body is screwed to a fastening member to connect a passage of the fastening member to a passage of a pipe moving inside the joint body in a non-rotating state, and Through the attachment member or the retainer mounted on the pipe, by sandwiching the gasket held by the fastening member or the pipe by the connection surface of the flow path,
A pipe joint for preventing leakage from a connecting surface of the flow path, wherein the gasket is fixed to the retainer on an outer periphery or a surface on a mounting side of the retainer. 2. The pipe joint according to claim 1, wherein the gasket is fixed to the retainer by any one of welding, bonding, and caulking. 3. The pipe joint according to claim 1, wherein the flow path of the pipe and the flow path of the fastening member are connected to another flow path by another pipe joint. Pipe fittings. 4. The pipe joint according to claim 1, wherein the flow path of the pipe and the flow path of the fastening member are connected to another flow path by welding. . 5. The pipe joint according to claim 1, wherein the pipe or the fastening member is a connection joint. 6. The pipe joint according to claim 1, wherein the pipe or the tightening member is a connection port for a fluid device. 7. The pipe joint according to any one of claims 1 to 4, wherein the pipe joint is used for connecting a flow path of each fluid device fixed at each mounting position. Pipe fittings. 8. The joint body is screwed into the fastening member to connect the flow paths of the two pipes that move inside the joint body in a non-rotating state, and are mounted on one of the pipes. In a pipe joint that prevents leakage from the connection surface of the flow path by sandwiching a gasket held on one of the pipes by a connection surface of the flow path via a retainer, the gasket may have an outer periphery or the retainer. A pipe joint characterized by being fixed to the retainer on a surface on the mounting side of (1). 9. The pipe joint according to claim 8, wherein the gasket is fixed to the retainer by any one of welding, bonding, and caulking. 10. The pipe joint according to claim 8, wherein a flow path of the pipe is connected to another flow path by another pipe joint. 11. The pipe joint according to claim 8, wherein a flow path of the pipe is connected to another flow path by welding. 12. The pipe joint according to claim 8, wherein one of the pipes is a connection joint. 13. The pipe joint according to claim 8, wherein one of the pipes is a connection port of a fluid device. 14. The pipe joint according to any one of claims 8 to 11, wherein the pipe joint is used for connecting a flow path of each fluid device fixed at each mounting position. Pipe fittings. 15. A fitting body is screwed into the fastening member to connect a flow path of the fastening member to a flow path of a pipe moving inside the fitting body in a non-rotating state, and By clamping a gasket held by the tightening member or the pipe with a connecting surface of the flow channel through a retaining member or a retainer mounted on the pipe with a biasing claw, the connecting surface of the flow channel A pipe joint for preventing leakage from a pipe, wherein a protective portion having the biasing claw portion is provided on the retainer. 16. The pipe joint according to claim 15, wherein the flow path of the pipe and the flow path of the fastening member are connected to another flow path by another pipe joint. 17. The pipe joint according to claim 15, wherein the flow path of the pipe and the flow path of the tightening member are connected to another flow path by welding. 18. The pipe joint according to claim 15, wherein the pipe or the fastening member is a connection joint. 19. The pipe joint according to claim 15, wherein the pipe or the tightening member is a connection port of a fluid device. 20. The joint body is screwed with the fastening member to move inside the joint body without rotation.
Along with connecting the flow paths of the pipes, via a retainer fitted with a biasing claw on one of the pipes,
In a pipe joint for preventing leakage from a connecting surface of the flow channel by sandwiching a gasket held on one side of the pipe by a connecting surface of the flow channel, the protection portion including the biasing claw portion may be provided by the retainer. A pipe joint characterized by being provided in a pipe. 21. The pipe joint according to claim 20, wherein a flow path of the pipe is connected to another flow path by another pipe joint. 22. The pipe joint according to claim 20, wherein a flow path of the pipe is connected to another flow path by welding. 23. The pipe joint according to claim 20, wherein one of the pipes is a connection joint. 24. The pipe joint according to claim 20, wherein one of the pipes is a connection port of a fluid device. 25. The pipe joint according to any one of claims 1 to 24, wherein the pipe joint is used in a semiconductor gas piping line.