JP2001032974A - Pipe joint structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple and quick pipe connection with superior workability and improved seal member adhesion for increased sealing effect and enhanced durability of a seal member. SOLUTION: The opening end of socket 12 is expanded as an outward collar and the inner periphery and the outer periphery are tapered faces 18, 19, respectively, enlarged in diameter toward the end. The opening end of the socket of a seal member 14 is formed as a diameter expanded portion and the outer periphery of the expanded diameter portion as a tapered outer periphery 20 to be fitted to the inner periphery tapered face 18 of the outward collar 12b of the socket, and the outer end face of the expanded diameter portion of the seal member in the direction of the pipe axis is provided with a tapered end face 21 contracted in diameter outwardly to the direction of the pipe axis. A thin push ring 22 is fixed to, at least, the tapered end face. The inner periphery of a tightening band 15 is provided with a thrust portion 24, which has a tapered seal thrust face abutting on the thin push ring, and an engagement portion 25, which has an engagement guide face abutting on the outward collar outer periphery tapered face 19 of the socket, one being opposed to the other in the direction of the pipe axis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, this type of pipe joint has been disclosed in
One disclosed in Japanese Patent Application No. 0-132166 is known. This pipe joint is used, for example, when piping a main pipe for drainage through each floor in a high-rise building, or when piping a horizontal drawing pipe connected to the main pipe, and the like.
4, as shown in FIG. 15, the pipe end 3a of the other pipe 3 is inserted into the socket 2 of one pipe 1 via the cylindrical sealing member 4 and tightened and connected by the tightening ring 5. I have.

The receiving port 2 has a tapered outer surface 2a on the opening edge side that expands in the tube axis direction. Also,
The seal member 4 has a bulged portion 4b having a tapered outer peripheral surface 4a which is bulged at a port opening end edge side and abuts on the tapered inner surface 2b of the port 2. Further, the tightening ring 5 is a C type that can be fitted around the socket 2 and has a dividing portion 6 at one location in the circumferential direction, and has tightening flange portions 5a and 5b at opposite ends of the dividing portion 6 to separate the ring. The space between the parts 6 can be expanded and contracted. Further, an engagement guide surface 5c and a seal pressing surface 5d which are in contact with a receiving taper outer surface 2a formed of a tapered surface facing the pipe axis direction are formed on an inner peripheral surface of the tightening ring 5, and the pressing ring 5 is provided with the pressing surface. The surface 5d presses the enlarged diameter portion 4b in the tube axis direction.

[0004]

By the way, in the above-mentioned prior art, there is an advantage that the pipes 1 and 3 can be easily and quickly connected to each other by tightening the tightening flange portions 5a and 5b with the bolts 7 and the nuts 8. . However, since the seal pressing surface 5d of the tightening ring 5 and the seal member 4 are in direct contact with each other, there is no slippage between the rings when tightening the ring, and circumferential distortion generated in the ring due to tightening is directly applied to the seal member. As a result, the pressing force in the pipe axis direction on the sealing member does not act uniformly, so that a reliable sealing function cannot be exerted, and the durability of the sealing member is impaired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and has as its object to easily and quickly connect pipes to each other with good workability. It is an object of the present invention to provide a pipe joint structure capable of making the pressing force uniform, improving the adhesion of the seal member, enhancing the sealing effect, and improving the durability of the seal member.

[0006]

According to the present invention, the following technical measures are taken to achieve the above object. That is,
According to the present invention, a C-end capable of radially expanding and contracting by inserting a pipe end of the other pipe into a socket of one pipe via a cylindrical sealing member and externally fitting the outer circumference of an opening end side of the socket. In the pipe joint structure tightened and connected by the mold tightening band, the opening end of the receiving port is expanded to form an outward flange, and the inner peripheral surface and the outer peripheral surface are tapered to increase in diameter toward the end. And, while the receiving port opening end side of the sealing member is a bulging portion,
The outer peripheral surface of the enlarged diameter portion is a tapered outer surface that fits with the inner peripheral tapered surface of the outward flange of the receiving port, and the outer diameter surface of the enlarged diameter portion of the sealing member in the tube axis direction is reduced outward in the tube axis direction. A thin pressing ring is interposed between at least the tapering end surface and the tightening band, and a tapered seal pressing surface abutting on the thin pressing ring on an inner peripheral surface of the tightening band and the receiving hole of the receiving port are provided. It is characterized in that an engagement guide surface that abuts on the outer peripheral taper surface of the outward flange portion is provided to face the tube axis direction.

According to this structure of the present invention, since the enlarged diameter portion of the seal member does not directly contact the seal pressing surface of the tightening band, the circumferential sliding between the pressing surface and the pressing ring at the time of band tightening. Occurs, and the circumferential distortion of the tightening band is not directly transmitted to the sealing member. Therefore, the pressing ring uniformly applies an axial pressing force to the sealing member over the entire circumference by the pressing ring, and the sealing effect is reliably obtained. And the durability of the sealing member is improved. When the seal member is incorporated into the pipe, since the pressing ring is integrated, the positioning of the inner peripheral end face of the pressing ring becomes unnecessary, and the workability and accuracy are greatly improved, and the sealing function is improved. Can be. In addition, it is possible to prevent metal-to-metal contact between the inner peripheral end surface of the pressing ring and the outer peripheral surface of the tube.

Further, the pipe joint structure according to the present invention is characterized in that the inner peripheral edge diameter of the thin-walled pressing ring is larger than the inner diameter of the sealing member. According to such a configuration, the inner peripheral end surface of the pressing ring does not completely contact the outer peripheral surface of the pipe, and the gap formed between the inner peripheral end face of the pressing ring and the pipe by the tightening of the sealing member is one of the sealing members. The portion enters and the adhesion to the outer peripheral surface of the tube is improved, so that the sealing effect can be further enhanced. Further, it is preferable that the pressing wheel has a thickness of 0.5 to 2.5 mm and an inner peripheral edge diameter is 1 to 4 mm larger than an inner diameter of the sealing member. If the thickness of the pressing ring is less than 0.5 mm, the workability of fixing to the seal member is poor, and if it exceeds 2.5 mm, the moldability is poor, the weight increases, and the manufacturing cost increases.
The difference between the inner peripheral edge diameter and the seal member inner diameter is 1 mm.
If it is less than the minimum value, the clearance with the outer peripheral surface of the pipe is too small to ensure sufficient adhesion of the sealing member, and even if the dimensional difference exceeds 4 mm, the adhesion of the sealing member becomes insufficient.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of a pipe joint structure according to the present invention. As shown in FIG. 1, the pipe joint structure according to the present invention is configured such that a pipe end 13 a of the other pipe 13 is connected to a receiving end 12 formed in one end of the one pipe 11 in an expanded shape. Inserted through the sealing member 14,
C-type tightening band 1 fitted to the opening end of the receiving port 12
The main construction is such that the bolt 5 and the nut 17 fasten the joint 5 together.

Hereinafter, for convenience of explanation, the tube 11 having the socket 12 is referred to as a "female tube", and the tube 13 having the other opening is referred to as a "male tube". The receiving port 12 of the female side pipe 11 has a large diameter portion 12a and an outward flange portion 1 having an enlarged end at the large diameter portion 12a.
2b, a tapered inner surface 18 and a tapered outer surface 19 whose diameter increases toward the receiving end edge are formed on the inner and outer peripheral sides of the flange portion 12b. The inner diameter of the large-diameter portion 12a is set between the outer peripheral surface of the male tube 13 and the sealing member 14.
The thickness is such that the thin cylindrical portion 14a can be interposed.

The sealing member 14 has a thin cylindrical portion 14a.
And an enlarged portion 14b formed in an outward flange shape at one end (outer end in the tube axis direction) and an inward flange portion 14c formed so as to protrude radially inward at the other end (inner end in the tube axis direction). The outer diameter of the enlarged diameter portion 14b is fitted into the receiving port 12 so as to protrude. The enlarged diameter portion 14b of the seal member 14 has a tapered outer peripheral surface 20 that increases in diameter from the thin cylindrical portion 14a toward the outer end in the tube axis direction. The tapered end face 21 is reduced in diameter toward the outer end in the axial direction.
As shown in FIG. 5, a thin pressing ring 22 made of a thin metal plate is integrally fixed to the outer end face 14d by a fixing means such as bonding or baking, and the thin pressing ring 22 is fixed to the tapered end face 21 by a tightening method which will be described later. It is interposed between the attached band 15.

The thin pressing ring 22 does not necessarily have to be fixed to the tapered end face 21 and the outer end face 14d, and achieves the object of the present invention only by being interposed between a fastening band 15 described later without being fixed. Can be. The thin-walled press ring 22 is formed by cutting a metal thin plate having a thickness of 0.5 mm to 2.5 mm into a ring shape and press-forming so that the cross-sectional shape becomes substantially “H” -shaped. And outer end surface 14d
Is fixed by an adhesive or baking. The inner diameter D of the pressing ring 22 is larger than the inner diameter d of the sealing member 14 (or the outer diameter of the male side tube 13) by an amount corresponding to the required clearance S. Due to the gap S, the pressing wheel 2
2 can be prevented from contacting the outer peripheral surface of the male side tube 13. The gap S is 0.5 mm
It is preferable to set it to 2 mm. Thereby, the adhesion of the seal member 14 to the outer peripheral surface of the male tube 13 can be secured, and the sealing effect can be enhanced.

The tapered outer peripheral surface 20 of the seal member 14 is in close contact with the tapered inner surface 18 of the receptacle 12 so as to enhance the sealing effect. The inner peripheral side of the outer end face 14d in the pipe axis direction of the seal member 14 is shown in FIG.
As shown in FIG. 2, the extension is extended to the outer end face of the pressing wheel 22, but this extension may be omitted. The cylindrical portion 14 a of the sealing member 14 is formed on the inner peripheral surface of the large-diameter portion 12 a of the receptacle 12 of the female tube 11 or the male tube 13.
The inner and outer diameters of the tube end 13a are determined so as to be able to come into contact with either one of the outer peripheral surfaces. The inner flange portion 14c of the seal member 14 is provided with the receiving large-diameter portion 12a of the female tube 11.
And the tube end 1 of the male side tube 13
3a is sandwiched between the end faces of the two pipes 11, 1
3 is formed so as to be flush with the inner peripheral surface.

The tightening band 15 is formed by pressing a metal band plate, for example, a stainless steel band plate, and as shown in FIG. 2, a C-shaped band main body 15a and the vicinity of the divided portion 23 of the main body 15a, that is, both ends. And fastening flange portions 15b, 15b which are spot-welded to the outer peripheral surface. As shown in FIG. 4, the band main body 15a is formed by cutting off a part of a ring in a circumferential direction to form a C-shape.
Its cross-sectional shape is substantially trapezoidal groove-shaped, and one of the opposing inner peripheral surfaces is a tapered seal pressing surface 24 a that comes into contact with the pressing ring 22.
And an inward flange-shaped engaging portion 25 having a tapered engagement guide surface 25a in which the other of the opposing inner peripheral surfaces abuts against the tapered outer surface 19 of the receptacle 12. And an outer peripheral wall portion 27 connecting the portions 24 and 25 in the width direction. The seal pressing surface 24a and the engagement guide surface 2
5a is provided with two notches 26 which divide the same into three in the circumferential direction, and an outer peripheral wall portion 27a of the notch 26 is provided.
Are easily bent, and the band main body 15a can be easily expanded and contracted.

The flange portion 15b has the same shape and size as the fixing portion 28 having the same curved surface as the outer peripheral wall surface of the main body 15a.
A fastening portion 29 substantially perpendicular to the fixing portion 28;
29 is provided with a reinforcing portion 30 for connecting an end portion in a width direction, that is, a tube axis direction, and a bolt hole 31 is provided in the fastening portion 29 (one is a U-shaped cutout, the other is a long hole). ing. The two flange portions 15b are fixed to the outer peripheral wall surface of the main body 15a by spot welding 32 such that the fixing portions 29 face the fixing portions 28. In the first embodiment, when the male side pipe 13 is inserted and connected to the receptacle 12 of the female side pipe 11, first, a seal member 14 is fitted into the receptacle 12 and preferably adhered by an adhesive. Then, the tightening portions 29, 29 of the tightening band 15 are pushed outward to expand the separating portion 23, that is, the tightening portion interval, and the outward flange portion 12b of the receiving port 12 and the enlarged diameter portion 14b of the seal member 14 Then, the fastening band 15 is externally fitted so as to wrap the pressing ring 22 from the outer peripheral side.

A bolt 16 having a bolt 17 passed through a bolt hole 31 (elongated hole) of one of the tightening portions 29 and a nut 17 screwed into a screw tip thereof is inserted into the bolt hole 31 of the one tightening portion 29. 31 (U-shaped cutout hole)
By rotating the bolt 16 in the screwing direction, the two tightening portions 29 are drawn toward each other, the diameter of the tightening band 15 is reduced, and the engaging guide surface 25a is brought into contact with the tapered outer surface 19 of the receiving port 12, and the seal is pressed. The surface 24a is lightly brought into contact with the pressing wheel 22 to temporarily fix it. In addition, if it is made to be shipped from the factory in this temporarily tightened state, the workability at the site such as piping becomes very good.

As described above, the female side tube 1 in the temporarily tightened state
The tube end 13a of the male-side tube 13 is inserted into one of the receiving ports 12, and the inner flange 14c of the sealing member 14 is sandwiched between the inner step 12c of the receiving port 12 and the tip of the pipe end 13a. To Next, the bolt 16 is rotated in the screwing direction,
The band body 15a is guided by the tapered outer surface 19 of the socket 12 and contracts radially inward by moving the two tightening portions 29 of the tightening band 15 toward each other inward.
Since the engagement guide surface 25a of 5a is engaged with the tapered outer surface 19 of the outward flange portion 12b, the thin pressing ring 22 is inward in the tube axial direction by the seal pressing surface 24a of the bunt main body 15a which is in contact therewith. It is pressed in the direction of the receptacle 12.

Therefore, since the seal member 14 is compressed along the pipe axis direction and expanded in the radial direction at the same time, the tapered outer peripheral surface 20 of the expanded diameter portion 14 b is formed on the tapered inner surface 18 of the receiving port 12. The inner peripheral surface of the enlarged diameter portion 14b of the seal member is strongly adhered to the outer peripheral surface of the tube end portion 13a of the male tube 13 while being strongly adhered. In this way, the connection and sealing between the female tube 11 and the male tube 13 can be easily and efficiently performed. According to the first embodiment, since the enlarged diameter portion 14b of the seal member 14 does not directly contact the seal pressing surface 24a of the tightening band 15, the circumferential direction between the pressing surface 24a and the pressing ring 22 at the time of band tightening. , The circumferential strain of the band body 15a of the tightening band 15 is not directly transmitted to the seal member 14, and therefore, the seal member 14 is provided with an axial pressing force by the pressing ring 22 over the entire circumference. It acts uniformly, ensures a sealing effect, and improves the durability of the sealing member 14.

The female tube 11 of the seal member 14
Also, when the push ring 22 is integrated into the receiving port 12, since the pressing ring 22 is integrated, the positioning of the inner peripheral end face of the pressing ring 22 becomes unnecessary, and the workability and accuracy are greatly improved, and the sealing function can be enhanced. In addition, it is possible to prevent metal-to-metal contact between the inner peripheral end surface of the press wheel 22 and the outer peripheral surface of the male tube 13. FIG. 6 shows a cross section of a main part of a pipe joint structure according to a second embodiment of the present invention, which is different from the first embodiment in that the cross-sectional shape of the pressing ring 22 is a one-letter type. It is possible to expect the same operation and effect as. Therefore, the same reference numerals as those in FIG.

FIG. 7 shows a cross section of a main part of a third embodiment of the pipe joint structure according to the present invention, which differs from the first embodiment in that the outermost peripheral surface of the enlarged diameter portion 14b of the seal member 14 has an annular shape. A convex portion 14e is formed, and an outer peripheral end of the pressing wheel 22 is bent toward the receiving port 12 to form an annular flange portion 22a.
The annular projection 14e is formed by the flange 22a and the end face of the receiving port 12.
Therefore, the same operation and effect as those of the first embodiment can be expected. Therefore, the same components as those of FIG. 5 are denoted by the same reference numerals as those of FIG. 5, and detailed description is omitted.

FIGS. 8 to 10 are views for explaining a method of manufacturing the tightening band 15 in the pipe joint structure according to the present invention, particularly a method of manufacturing the band main body 15a. As shown in FIG. 8, the band main body 15a cuts a metal band plate, for example, a stainless steel band plate to a required length, and has both ends in the width direction at the pressing portion forming portion 24A and the engaging portion forming portion 25.
A cut-out portion 26 is provided at A at a position that divides this into three in the longitudinal direction to reach the outer peripheral wall portion 27a, and the band body material 33 is formed. Then, the blank 33 is pressed by the press at the position indicated by the one-dot chain line 34 in FIG.
And the engaging portion 25 are bent inwardly in the width direction to form a trapezoidal groove shape so as to form an inward flange, and as shown in FIG. The outer flange portion 12b is curved so as to form an arc having the same radius of curvature as the radius of the outermost end face of the outer flange portion 12b, and the outer peripheral wall portion 27a between the cutout portions 26 is curved in the opposite direction to be in a developed state.

By forming into the developed shape shown in FIG. 9, the structure of the press die becomes very simple, and the press die can be manufactured easily, accurately and at low cost. Then, the tightening flange portion 15b separately press-molded on the outer surface of the outer peripheral wall portion 27 at both ends thereof is fixed to the band main body 15a formed as shown in FIG. The fastening band 15 in the deployed state shown in FIG. 10 can be completed. When the tightening band 15 in the unfolded state shown in FIG.
The opposing inner surfaces of the center or left and right curved portions of the band main body 15a, that is, the engagement guide surface 25a and the seal pressing surface 24a are pressed against the tapered outer surface 19 and the pressing wheel 22 of the socket outward flange 12b, and the gap between the notches 26 is formed. The outer peripheral wall portion 27a is bent in a direction in which the outer peripheral wall portion 27a extends substantially straight, and
b may be opposed to each other and connected by bolts 16 and nuts 17 as shown in FIG.

FIGS. 11 to 13 show another manufacturing method of the tightening band 15 of the pipe joint structure according to the present invention. This is different from the above-mentioned method. As shown in FIG. 11, a band forming material 35 in this band forming method includes a tightening portion forming portion 29A and a reinforcing portion forming portion 30 which constitute the flange portion 15b.
A is provided. When the material 35 is press-formed, the seal pressing portion forming portion 24A and the engaging portion forming portion 25A are opposed inward in the width direction in the same manner as described above at the positions indicated by dashed lines 36, 36 in FIG. And the outer peripheral wall portion forming portion 27A is curved in an arc shape. On the other hand, the fastening portion forming portion 29A is formed into an outer peripheral wall portion forming portion 27A.
And the reinforcing portion forming portion 30A is located at a position shown by a one-dot chain line 37 in FIG. The outer peripheral wall portion 2 is bent substantially at right angles inward on the opposite side.
7, the reinforcing portion forming portion 30 </ b> A is welded 38 to the outer peripheral wall portion 27 (see FIG. 13) after being brought into contact with the outer surface.
As shown in FIG. 10, the integrated tightening band 15 in the unfolded state.
Can be completed.

In the case where the thus-formed unified tightening band 15 is assembled in the state shown in FIG. 12, it can be performed in the same manner as the one formed by the above-described method. According to the method of forming the integrated clamping band 15, only one set of molding dies is required, and it is possible to obtain the mold with high precision, ease, and low cost. In the present invention,
The number of the cutout portions 26 of the tightening band 15 is two in the above embodiment, but may be one, or three or more. Further, the present invention is not limited to the above embodiment, and the design can be appropriately changed.

For example, the seal member 14 is provided on the male side tube 1.
3 may be adhered to the outer surface of the pipe end.
It is not necessary to adhere to 1 and 13. Also, sealing member 1
4 may have a structure that does not include one or both of the cylindrical portion 14a and the inner flange portion 14c. When the cylindrical portion 14a is not provided, the large diameter portion 12a of the receiving port 12 is unnecessary. Further, the bolt holes 3 of the tightening band 15 are formed.
1 has a long hole on one side and a cutout on the other,
Both can be slots or U-shaped notches.

[0026]

As described above, in the pipe joint structure according to the present invention, the opening end of the receiving port of one of the pipes is expanded to form an outward flange, and the inner peripheral surface and the outer peripheral surface have the ends. A tapered surface that increases in diameter toward the portion, and the receiving opening opening end side of the seal member is a bulged portion, and the outer peripheral surface of the bulging portion is an outer peripheral flange inner peripheral tapered surface of the receiving port. A tapered outer surface to be fitted, and a tube axial direction outer end surface of the expanded portion of the seal member has a tapered end surface whose diameter is reduced outward in the tube axial direction, and at least a thin wall between the tapered end surface and the tightening band. A pressing wheel is interposed,
A tapered seal pressing surface abutting on the thin pressing ring and an engaging guide surface abutting on an outward flange portion pa surface of the receiving port are provided on an inner peripheral surface of the tightening band in a tube axial direction facing shape. Since the pipes are connected easily and quickly, the workability is good, and the circumferential strain generated when tightening and reducing the diameter of the tightening band can be prevented from being directly transmitted to the seal member. In this case, the pressing force in the tube axis direction can be made uniform to improve the adhesion of the sealing member, enhance the sealing effect, and improve the durability of the sealing member.

When the inner peripheral edge diameter of the thin-walled pressing ring is larger than the inner diameter of the sealing member, it is possible to prevent metal contact between the inner peripheral end face of the pressing ring and the outer peripheral surface of the pipe.

[Brief description of the drawings]

FIG. 1 is a partially broken front view showing a first embodiment of a pipe joint structure according to the present invention.

FIG. 2 is a front view of the tightening band in the embodiment.

FIG. 3 is a right side view of FIG. 2;

FIG. 4 is a sectional view taken along line AA of FIG. 2;

FIG. 5 is an enlarged view of a portion B in FIG. 1;

FIG. 6 is a sectional view of a main part (corresponding to a section B in FIG. 1) showing a second embodiment of the pipe joint structure according to the present invention.

FIG. 7 is a sectional view of a main part (corresponding to a section B in FIG. 1) showing a third embodiment of the pipe joint structure according to the present invention.

FIG. 8 is a plan view of a band body forming material of a tightening band in the pipe joint structure according to the present invention.

FIG. 9 is a developed front view of the band main body after press molding is completed.

FIG. 10 is an exploded front view of the completed tightening band.

FIG. 11 is a plan view of an integrally molded material of a tightening band in the pipe joint structure according to the present invention.

FIG. 12 is a front view showing a fastening portion connected state of a fastening band formed integrally.

FIG. 13 is a sectional view taken along line CC of FIG. 12;

FIG. 14 is a sectional view of a conventional example.

FIG. 15 is a front view of a fastening ring in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 One pipe (female side pipe) 12 Reception port 12b Outer flange 13 The other pipe (male side pipe) 13a Pipe end part 14 Seal member 14a Inflated part 15 Tightening band 18 Tapered inner surface 19 Tapered outer surface 20 Tapered outer peripheral surface 22 Thin-walled press wheel 24 Pressing portion 24a Seal pressing surface 25 Engagement portion 25a Engagement guide surface

Claims (3)

[Claims] 1. The end of one tube is connected to the end of the other tube.
A pipe joint structure which is inserted through a cylindrical sealing member and tightened and connected by a radially expandable and contractable C-shaped tightening band which is externally fitted to an outer periphery of an opening end of the socket, wherein an opening end of the socket is provided. Is expanded to form an outward flange portion, and the inner peripheral surface and the outer peripheral surface are tapered surfaces that increase in diameter toward an end portion, and the receiving port opening end side of the seal member is an expanded diameter portion. The outer peripheral surface of the enlarged diameter portion is a tapered outer surface fitted with the inner peripheral tapered surface of the outward flange portion of the receiving port, and the outer peripheral surface of the enlarged diameter portion of the seal member in the axial direction is reduced outward in the axial direction. A tapered end face having a diameter is provided, and a thin-walled press ring is interposed at least between the tapered end face and the tightening band, and a tapered seal pressing surface abutting the thin-walled press ring on an inner peripheral surface of the tightening band and the bearing. The engagement guide surface that abuts on the outer tapered surface of the outward flange of the mouth is A pipe joint structure provided in a direction. 2. An inner peripheral edge diameter of said thin pressing ring is larger than an inner diameter of a sealing member.
The pipe joint structure according to the above. 3. The thin pressing ring having a thickness of 0.5 to 2.
3. The pipe joint structure according to claim 1, wherein the diameter is 5 mm, and the inner peripheral edge diameter is 1 to 4 mm larger than the inner diameter of the seal member. 4.