JP4221348B2 - Connection structure between flange piping and connection structure between flange piping and fluid equipment - Google Patents

Description

  The present invention relates to a connection structure between flange pipes and a connection structure between flange pipes and a fluid device, and more specifically, is handled in manufacturing processes in various technical fields such as semiconductor manufacturing, medical / pharmaceutical manufacturing, food processing, and chemical industry. The present invention relates to a connection structure for connecting flange piping used in a piping system of high-purity liquid or ultrapure water, or for connecting various fluid devices such as pumps and valves to flange piping.

  Conventionally, as means for connecting flange pipes so that fluid can freely pass through their fluid passages, the first flange part of the first flange pipe which is one flange pipe and the other flange are used. In general, a structure is adopted in which the second flange portion of the second flange pipe, which is a pipe, is fastened and fixed using a plurality of bolts and nuts via a ring-shaped gasket therebetween. As such an example, those disclosed in Patent Document 1 and Patent Document 2 are known.

Also, when connecting and connecting the flange pipe and a fluid device such as a pump or a valve, a connection structure according to the above-described connection structure between the flange pipes is employed. That is, this is a connection structure in which the flange portion of the flange pipe and the end portion of the fluid supply / exhaust port portion of the fluid device are opposed to each other via a gasket, and both are tightened and connected by a bolt or the like.
Japanese Patent Laid-Open No. 2000-120953 Japanese Patent Laid-Open No. 10-231969

In the connection structure described above, effective sealing performance is obtained by tightening the bolts until the predetermined surface pressure is reached between the pair of flange portions between which the gasket is sandwiched. However, since the bolt tightening force decreases with time, it has been necessary to periodically perform additional tightening in order to prevent the tightening force from decreasing, that is, leakage from the connection portion due to torque reduction. When sealing with a gasket, a very high tightening force is required. Therefore, high strength is required for the flange part of the flange piping and the fluid supply / exhaust part of the fluid equipment. It was also disadvantageous in terms of sex. Further, in the connection structure disclosed in Patent Documents 1 and 2 described above, irregularities in the fluid passage inside diameter of the gasket than the diameter of the fluid passage of the tubular at the flange portion of the flange piping and fluid equipment be one slightly larger Since it exists, there is a possibility that a liquid pool is generated in the portion, which may hinder high purity and cleanliness.

  The present invention has been made in view of such circumstances, and its object is to devise a connection structure between flange pipes in a liquid piping system and a connection structure between flange pipes and a fluid device. Accordingly, it is possible to maintain a good sealing performance with little additional tightening and to improve the assembling workability. Another object of the present invention is to achieve high purity by eliminating a liquid pool in the connecting portion.

The invention according to claim 1 of the present invention is the first flange pipe having the first flange portion 1B having a diameter larger than that of the tubular portion 1A and made of synthetic resin at the end portion of the tubular portion 1A having the tubular fluid passage 4. 1st flange part 1B of 1 and the 2nd flange piping which has the 2nd flange part 2B which is larger diameter than this tubular part 2A, and is made of a synthetic resin in the end part of tubular part 2A which has the tubular fluid passage 4 In the connection structure between the flange pipes, the second flange portion 2B is connected to and communicated with each other via a ring-shaped gasket G interposed between the first flange portion 1B and the second flange portion 2B.
The fluid passage 4 is opened so that the first flange portion 1B and the second flange portion 2B communicate with each other in a face-to-face relationship with each other, and a first seal end t1 is provided on the first flange portion 1B. And each of the second flange portions 2B is provided with a second seal end t2.
The first seal end portion t1 and the second seal end portion t2 are annular grooves formed in the outer diameter side portion of the fluid passage 4 opened at the end surfaces of the first flange portion 1B and the second flange portion 2B. 6 or an annular projection 18,
The gasket G is fitted to the annular groove 6 or the annular protrusion 18 of the first seal end t1 in the outer diameter side portion of the fluid passage 9 that opens to one end face facing the end face of the first flange portion 1B. An annular protrusion 8 or an annular groove 16 is formed, and an outer diameter side portion of the fluid passage 9 that opens to the other end surface facing the end surface of the second flange portion 2B of the gasket G, the second seal end t2 An annular protrusion 8 or an annular groove 16 that fits into the annular groove 6 or the annular protrusion 18 is formed,
The first flange portion 1B and the second flange portion 2B are attracted to each other via the gasket G across the first flange portion 1B and the second flange portion 2B, and this attracted state is maintained. Attracting means M for
Due to the pulling action of the pulling means M, the annular groove 6 or the annular protrusion 18 of the first seal end t1 and the annular protrusion 8 or the annular groove 16 of one end surface of the gasket G are included in the two seals. Flange piping configured such that the annular groove 6 or the annular protrusion 18 of the end t2 and the annular protrusion 8 or the annular groove 16 of the other end face of the gasket G are fitted together to form the fitting seal part 3. The connection structure between the two
The first seal end t1 or the second seal end t2 is constituted by the annular protrusion 18;
An annular second joint end 17 is formed between the annular projection 18 and the fluid passage 4 at the first seal end t1 or the second seal end t2 constituted by the annular projection 18, and this A tapered outer peripheral surface 17a that is tapered and tapered on the outer peripheral surface of the tip of the second joint end 17 is formed.
The annular groove 16 and the fluid passage 9 are formed on one end surface or the other end surface of the gasket G in which the annular groove 16 that fits the annular protrusion 18 of the first seal end t1 or the second seal end t2 is formed. An annular first joint end 15 is formed between the two ends, and a taper inner peripheral surface 15a that abuts the taper outer peripheral surface 17a is formed in a tapered shape on the tip inner peripheral surface of the first joint end 15. ,
The tapered inner peripheral surface 15a and the tapered outer peripheral surface 17a are brought into pressure contact with each other by pulling the first flange portion 1B and the second flange portion 2B through the gasket G by the pulling means M. It is configured.

The invention according to claim 2 is the connection structure between flange pipes according to claim 1, wherein the attracting means M has an outer diameter larger than that of the first flange portion 1B and the first and second flange pipes. A first split ring 25 fitted on the tubular portion 1A of the first flange pipe 1 so as to interfere with the first flange portion 1B in the direction of the axial center P of 1, 2;
An inward flange 24 having an opening 24a that allows passage of the first flange portion 1B and interferes with the first split ring 25 in the direction of the axis P is formed at one end, and the other A first cylindrical nut 22 having a male screw portion 22n formed on the outer periphery of the end;
A second split ring that has an outer diameter larger than that of the second flange portion 2B and is fitted on the tubular portion 2A of the second flange pipe 2 so as to interfere with the second flange portion 2B in the direction of the axis P. 25,
An inward flange 24 having an opening 24a that allows passage of the second flange portion 2B and interferes with the second split ring 25 in the axial center P direction is formed at one end, and the other A second cylindrical nut 23 formed with an internal thread 23n that can be screwed into the external thread 22n on the inner periphery of the end;
The first flange portion 1B and the second flange portion 2B are connected to each other by the tightening operation of the cylindrical nuts 22 and 23 by screwing the male screw portion 22n and the female screw portion 23n. It is comprised so that it may be drawn through.

According to a third aspect of the present invention, in the flange pipe-to-flange connection structure according to the first aspect, the attracting means M can be screwed into a male screw portion 1n formed on the outer peripheral portion of the first flange portion 1B. A cylindrical nut 21 having a female threaded portion, an outer diameter larger than that of the second flange portion 2B, and the second flange portion 2B in the direction of the axis P of the first and second flange portions 1B, 2B. A split ring 25 fitted on the tubular portion 2A of the second flange pipe 2 so as to interfere,
An inward flange 24 having an opening 24a that allows passage of the second flange portion 2B and interferes with the split ring 25 in the axial center P direction is provided at one end of the cylindrical nut 21. Formed,
The first flange portion 1B and the second flange portion 2B are configured to be attracted to each other via the gasket G by a tightening operation of the cylindrical nut 21 to the male screw portion 1n. Features.

The invention according to claim 4 is characterized in that the flange pipe connection structure according to claim 2 or 3 is provided with at least one of the following configurations (a) and (b). (A) The inner peripheral surface portions 21m, 22m, and 23m of the split ring inner fitting portion adjacent to the inward flange 24 of the cylindrical nuts 21, 22, and 23 are flat concentrically with the tubular fluid passage 4. An inner diameter of the inner peripheral surface portions 21m, 22m, and 23m and an outer diameter of the split ring 25 formed in a rectangular cross section are formed to have substantially the same diameter. (B) The outer diameter portions of the tubular portions 1A, 2A fitted to the split ring 25 are formed on a flat outer peripheral surface concentrically with the tubular fluid passage 4, and outside the outer diameter portion. The diameter and the inner diameter of the split ring 25 are formed to have substantially the same diameter.

According to a fifth aspect of the present invention, in the connecting structure between flange pipes according to the first aspect, the drawing means M is arranged in a state along the axial center P direction of the first and second flange pipes 1 and 2. It is composed of a bolt 41 and a nut 42 that pass through holes 1h and 2h formed in the flange portions 1B and 2B, respectively.
The nut 42 is fastened to the bolt 41 so that the first flange portion 1B and the second flange portion 2B are attracted to each other via the gasket G.

The invention according to claim 6 is the connection structure between flange pipes according to any one of claims 1 to 5, wherein the first and second flange portions 1B and 2B and the gasket G are formed of a fluororesin. It is characterized by being.

The invention according to claim 7 is the flange portion 2B of the flange pipe 2 having a flange portion 2B having a diameter larger than that of the tubular portion 2A and made of synthetic resin at the end portion of the tubular portion 2A having the tubular fluid passage 4. The fluid supply / discharge port portion 31b of the fluid device 31 including the fluid supply / discharge port portion 31b having a tubular fluid passage 34 made of synthetic resin is connected to the flange portion 2B and the fluid supply / discharge port portion 31b. In the connection structure between the flange piping and the fluid device that are connected in communication via a ring-shaped gasket G interposed between them,
The fluid passages 4 and 34 are opened so that the flange portion 2B and the fluid supply / exhaust port portion 31b communicate with each other in a face-to-face relationship, and a second seal end t2 is provided in the flange portion 2B. The fluid supply / exhaust port 31b is provided with a first seal end t1, respectively.
The first seal end portion t1 and the second seal end portion t2 are annular shapes formed on the outer diameter side portions of the fluid passages 34, 4 that open to the end surfaces of the fluid supply / discharge port portion 31b and the flange portion 2B. It is constituted by the groove 6 or the annular protrusion 18,
An annular projection that fits into the annular groove 6 or the annular projection 18 of the first seal end t2 on the outer diameter side portion of the fluid passage 9 that opens to one end surface facing the end surface of the flange portion 2B of the gasket G. 8 or an annular groove 16 is formed on the outer diameter side portion of the fluid passage 9 that opens to the other end surface of the gasket G that faces the end surface of the fluid supply / discharge port portion 31b. An annular protrusion 8 or an annular groove 16 that fits into the annular groove 6 or the annular protrusion 18 is formed,
The flange 2B and the fluid supply / exhaust port 31b are pulled together through the gasket G over the flange 2B and the fluid supply / exhaust port 31b, and at the same time, the pull is maintained. Provided with a shifting means M;
Due to the pulling action of the pulling means M, the annular groove 6 or the annular protrusion 18 of the first seal end t1 and the annular protrusion 8 or the annular groove 16 of one end surface of the gasket G are included in the two seals. Flange piping configured such that the annular groove 6 or the annular protrusion 18 of the end t2 and the annular protrusion 8 or the annular groove 16 of the other end face of the gasket G are fitted together to form the fitting seal part 3. And fluid equipment connection structure,
The first seal end t1 or the second seal end t2 is constituted by the annular protrusion 18;
An annular second joint end 17 is formed between the annular protrusion 18 and the fluid passages 34 and 4 at the first seal end t1 or the second seal end t2 constituted by the annular protrusion 18. In addition, a tapered outer peripheral surface 17a that is tapered and tapered on the outer peripheral surface of the tip end of the second joint end portion 17 is formed.
The annular groove 16 and the fluid passage 9 are formed on one end surface or the other end surface of the gasket G in which the annular groove 16 that fits the annular protrusion 18 of the first seal end t1 or the second seal end t2 is formed. An annular first joint end 15 is formed between the first joint end 15 and a taper inner peripheral surface 15a that abuts against the taper outer peripheral surface 17a is formed in a tapered shape on the tip inner peripheral surface of the first joint end 15. And
  The tapered inner peripheral surface 15a and the tapered outer peripheral surface 17a are brought into pressure contact with each other by pulling the flange portion 2B and the fluid supply / discharge port portion 31b through the gasket G by the pulling means M. It is configured.

According to an eighth aspect of the present invention, in the connection structure between the flange pipe and the fluid device according to the seventh aspect, the attracting means M is a male screw portion 31n formed on the outer peripheral portion of the fluid supply / discharge port portion 31b. A cylindrical nut 21 having a female screw portion 21n that can be screwed to the flange portion 2B, and an outer diameter larger than that of the flange portion 2B, and the flange in the axial center P direction of the flange portion 2B and the fluid supply / discharge port portion 31b. A split ring 25 fitted on the tubular portion 2A of the flange pipe 2 so as to interfere with the portion 2B,
An inward flange 24 having an opening 24a that allows passage of the flange 2B and interferes with the split ring 25 in the direction of the axis P is formed at one end of the cylindrical nut 21. And
The flange portion 2 </ b> B and the fluid supply / discharge port portion 31 b are configured to be pulled together via the gasket G by a tightening operation of the cylindrical nut 21 to the male screw portion 31 n. And

The invention according to claim 9 is the connection structure between the flange pipe and the fluid device according to claim 7, wherein the attracting means M has an outer diameter larger than that of the flange portion 2B and the flange portion 2B and the fluid device. A first split ring 25 fitted on the tubular portion 2A of the flange pipe 2 so as to interfere with the flange portion 2B in the direction of the axis P of the fluid supply / discharge port portion 31b;
An inward flange 24 having an opening 24a that allows passage of the flange portion 2B and interferes with the first split ring 25 in the axial center P direction is formed at one end portion, and the other end portion. A first cylindrical nut 23 having a male screw portion 23n formed on the outer periphery thereof;
The fluid supply / discharge port portion 31b has an outer diameter larger than an outward flange 31f formed at the end of the fluid supply / discharge port portion 31b and is external to the fluid supply / discharge port portion 31b so as to interfere with the outward flange 31f in the axis P direction. A second split ring 27 to be fitted;
An inward flange 24 having an opening 24a that allows passage of the outward flange 31f and interferes with the second split ring 27 in the direction of the axis P is formed at one end, and the other end A second cylindrical nut 22 formed with an internal thread portion 22n that can be screwed into the external thread portion 23n on the inner periphery of the portion,
The flange portion 2B and the fluid supply / exhaust port portion 31b are mutually connected to each other by the tightening operation of the cylindrical nuts 23 and 22 by screwing the male screw portion 23n and the female screw portion 22n. It is comprised so that it may be drawn through.

The invention according to claim 10 is the connection structure between the flange pipe and the fluid device according to claim 8 or 9, wherein at least one of the following (A) and (B) is provided. Features. (A) The inner peripheral surface portions 21m, 22m, and 23m of the split ring inner fitting portion adjacent to the inward flange 24 of the cylindrical nuts 21, 22, and 23 are concentric with the tubular fluid passages 4 and 34. It is formed on a flat inner peripheral surface, and the inner diameters of the inner peripheral surface portions 21m, 22m and 23m and the outer diameters of the split rings 25 and 27 formed in a rectangular cross section are formed to have substantially the same diameter. . (B) The outer diameter portion of the tubular portion 2A or the fluid supply / discharge port portion 31b on which the split rings 25 and 27 are fitted is formed on a flat outer peripheral surface concentric with the tubular fluid passages 4 and 34. In addition, the outer diameter of the outer diameter portion and the inner diameters of the split rings 25 and 27 are formed to have substantially the same diameter.

According to an eleventh aspect of the present invention, in the connection structure between the flange pipe and the fluid device according to the seventh aspect, the attracting means M includes an outward flange 31f formed on an outer periphery of the fluid supply / discharge port portion 31b. Bolts 41 that pass through holes 2h and 31h formed in the flange portion 2B and the outward flange 31f, respectively, in a state along the axis P direction of the flange portion 2B and the fluid supply / discharge port portion 31b. And a nut 42,
The flange portion 2 </ b> B and the fluid supply / exhaust port portion 31 b are configured to be attracted to each other via the gasket G by tightening the nut 42 to the bolt 41.

The invention according to claim 12 is the connection structure between the flange pipe and the fluid device according to any one of claims 7 to 11, wherein the fluid supply / exhaust port portion 31b, the flange portion 2B, and the gasket G are provided. It is characterized by being made of a fluorine resin.

According to the first aspect of the present invention, the annular groove and the annular protrusion are connected to the flange pipe by the gasket and the flange parts sandwiched between the flange part of the first flange pipe and the flange part of the second flange pipe. Since a fitting seal part is formed by fitting along the axial direction, an excellent sealing action is exhibited even if these flange sealing parts do not strongly press each other only by the presence of these fitting seal parts. Become so. Therefore, the pulling means for connecting both flange pipes does not need to be tightened with a high pressure as in the prior art when sandwiching the gasket between both flange portions, and it is sufficient to tighten and fix with a normal tightening force. Since there is no change in the inner diameter of the gasket due to strong tightening, the fluid passage of the gasket and the fluid passage of the flange pipe can be made to have a constant diameter without any irregularities so that no liquid pool is generated. As a result, torque reduction with time-dependent change of the attracting means is reduced, and tightening is unnecessary or almost not required. Good sealing performance can be maintained over a long period of time, and assembly workability is also improved. An improved connection structure between flange pipes can be provided.

The first seal end t1 and the second seal end formed in the first and second fluid supply / discharge ports, respectively, and the annular protrusion or ring formed on one end surface and the other end surface of the gasket, respectively. Since the groove fits with each other to form a fitting seal portion, it is possible to prevent liquid leakage from between the first and second fluid supply / discharge ports and to obtain excellent sealing performance.

For example, if such a connection structure is used in the piping system of a cleaning device in a semiconductor manufacturing facility, the area occupied by the device can be reduced while ensuring good sealing performance, and a large flow path is secured. As a result, the circulation flow rate is increased, and the high purity of the chemical solution can be enhanced to contribute to the yield improvement.

The fluid supply / exhaust ports are attracted by the attracting means so as to approach each other via the gasket, and the approaching state can be maintained, so that the fluid devices ensure good sealing performance without liquid leakage. The obtained state can be maintained over a long period of time, and a connection structure between fluid devices having excellent reliability can be provided.

According to the first aspect of the present invention, in the seal connection state, the inner diameter side of the fitting portion between the annular protrusion at the first seal end or the second seal end and the annular groove at one end face or the other end face of the gasket In addition, there is a configuration in which the taper inner peripheral surface of the first joint end and the taper outer peripheral surface of the second joint end are in pressure contact with each other, so that the sealing property is further improved and there is no liquid pooling portion, resulting in high purity. In addition to the construction of the seal portion that can promote the following effects, the following effects can be obtained.

That is, when the rigidity of the inner diameter side portion of the annular groove is insufficient, the first joint end portion of the gasket may be inclined and deformed toward the inner diameter side as the annular protrusion is fitted into the annular groove. However, the first joint end to be inclined and deformed is supported by the first seal end or the second seal end of the second seal end from the inner diameter side, and the first joint end lacks rigidity. Therefore, it is possible to prevent the inclination deformation toward the inner diameter side, thereby securing a tubular fluid passage in which no liquid pool is generated.

According to the invention which concerns on Claim 2, the 1st cylindrical nut and 2nd flange piping with which the 1st flange piping side is equipped via the 1st and 2nd split type ring externally fitted by each tubular part Fitting the ring-shaped protrusion or ring groove on the first and second flanges with the ring-shaped groove or ring protrusion on the gasket side by simply screwing and tightening the second cylindrical nut on the side Thus, the first and second flange portions, that is, the first and second flange pipes can be connected in communication. A convenient and easy-to-handle pulling means that can maintain the connection state by simply stopping the screwing of the cylindrical nuts can be obtained as a compact and space-saving rational means.

In addition, since a pair of split rings and a pair of cylindrical nuts are used, each flange portion does not need a configuration for connection such as forming a screw, and the first and second flange portions are the same. It is also preferable that each flange portion can be made common and inexpensive, such as being able to be made.

In addition, each cylindrical nut can be externally fitted to and detached from the corresponding flange part, and in the externally fitted state, it interferes with the corresponding flange part in the axial direction via the split ring, so a pair of cylindrical nuts The split ring and the cylindrical nut can be retrofitted to the first and second flange pipes while allowing direct connection between the first and second flange portions.

In addition, it is possible to reliably transmit the tightening force between the cylindrical nuts to the first and second flange portions while making it rational that only a small number of parts are required. Therefore, a pair of cylindrical nuts and a pair of split rings are used without taking the difficult manufacturing method of fitting the cylindrical nuts corresponding to the first and second flange pipes into the tubular portions. Connection operation between flange pipes can be done easily and conveniently.

According to the third aspect of the present invention, the cylindrical nut engaged with the second flange part via the split ring is simply operated by screwing the male nut of the first flange part into the first nut. It is possible to connect the first and second flange portions, that is, the first and second flange pipes, by fitting the annular protrusion or annular groove of the first and second flange portions with the annular groove or annular protrusion on the gasket side. it can. A convenient and easy-to-handle attracting means that can maintain the connection state by simply stopping the screwing of the cylindrical nut can be obtained as a compact and space-saving rational means.

  Further, the cylindrical nut can be freely fitted and detached from the second flange portion, and in the fitted state, the cylindrical nut interferes with the second flange portion via the split ring in the axial direction. The split ring and the cylindrical nut can be retrofitted to the second flange pipe while allowing direct connection between the two flange portions. In addition, it is possible to reliably transmit the tightening force of the cylindrical nut to the second flange portion with a small number of parts and only one kind of parts that is economical and reasonable. Therefore, the connecting operation between the flange pipes using the cylindrical nut is simple and convenient without taking the difficult manufacturing means of attaching the cylindrical nut to the tubular portion when the second flange pipe is manufactured. Yes.

According to the invention described in claim 4 , (a) a portion adjacent to the inward flange at the inner back portion of the inner diameter portion of the cylindrical nut is formed on the flat inner peripheral surface portion concentric with the tubular fluid passage, and A configuration in which the inner diameter of the inner peripheral surface portion and the outer diameter of the split ring formed in a rectangular cross section are formed to have substantially the same diameter, and (b) the outer diameter portion of the tubular portion in which the split ring is externally fitted Is formed on a flat outer peripheral surface concentrically with the fluid passage of the tubular portion, and has at least one of a configuration in which the outer diameter of the outer diameter portion and the inner diameter of the split ring are formed to have substantially the same diameter. Therefore, when the cylindrical nut is screwed, the split ring is tilted and it is in a state where it is tilted, or the axial pressing force due to the screwing of the cylindrical nut is not transmitted well to the flange part. The occurrence of defects can be reduced, and the flange part can be effectively Made pressure, the advantage of being able to satisfactorily attracting in a direction toward the flange portions to each other to each other is obtained. In particular, if both (A) and (B) are provided, the above-mentioned problems can be prevented, and the above-described effects can be further enhanced.

According to the fifth aspect of the present invention, the pulling means is configured by simple means of providing bolts and nuts penetrating between both flange portions by passing holes formed in both flange portions. be able to. That is, it is possible to obtain a connection structure between flange pipes having various advantages while being a simple and inexpensive drawing means.

According to the invention of claim 6 , since the first and second flange portions are formed of a fluororesin having excellent chemical resistance and heat resistance, the fluid is a chemical solution or a chemical liquid. However, even if it is a high-temperature fluid, the connection structure portion is not deformed and easily leaks, and a good sealing property can be maintained .

The fluororesin is a resinous substance obtained by polymerization of ethylene and derivatives thereof in which one or more hydrogen atoms are substituted with fluorine, and is stable at high temperatures and excellent in water repellency.

Further, it is preferable in that it has a small coefficient of friction, extremely high chemical resistance, and high electrical insulation.

According to the invention concerning Claim 7, the said effect by the invention concerning Claim 1 can be exhibited similarly also in the connection structure of flange piping and a fluid apparatus.

According to the invention concerning Claim 8 , the said effect by the invention concerning Claim 2 can be exhibited similarly also in the connection structure of flange piping and a fluid apparatus.

According to the invention concerning Claim 9 , the said effect by the invention concerning Claim 3 can be exhibited similarly also in the connection structure of flange piping and a fluid apparatus.

According to the invention of claim 1 0, the function and effect of the invention according to claim 4, can be exhibited also in the connecting structure between the flange pipe and fluid apparatus.

According to the invention of claim 1 1, the function and effect of the invention according to claim 5, can be exhibited also in the connecting structure between the flange pipe and fluid apparatus.

According to the invention according to claim 1 2, the function and effect of the invention according to claim 6, can be exhibited also in the connecting structure between the flange pipe and fluid apparatus.

Hereinafter, preferred embodiments of a connection structure between flange pipes according to the present invention and a connection structure between flange pipes and a fluid device will be described with reference to the drawings. FIGS. 1-8 is a figure regarding the connection structure of flange piping, It demonstrates as the reference examples 1 and 2, Example 1, and the reference example 3. FIG. 9 to 15 are diagrams relating to the connection structure between the flange pipe and the fluid device, and will be described as Reference Examples 4, 5, Example 2 and Reference Examples 6 , 7. FIG.
(Reference Example 1 )

As shown in FIG. 1, the flange pipe connection structure according to the reference example 1 is provided at the end of a tubular portion 1A having a circular fluid passage 4 at a first flange having a larger diameter and a circular section than the tubular portion 1A. At the end of the first flange portion 1B of the first flange pipe 1 made of a fluororesin (an example of synthetic resin) such as PTFE having the portion 1B and the tubular portion 2A having the circular fluid passage 4, the tubular portion The second flange portion 2B of the second flange pipe 2 made of a fluororesin (an example of synthetic resin) such as PTFE having a second flange portion 2B having a diameter larger than 2A and a circular cross section is connected to the first flange portion 1B and the second flange portion 2B. It is comprised as a connection part of flange piping connected in communication via the ring-shaped gasket G interposed between 2 flange parts 2B.

In the reference example 1, the first flange pipe 1 and the second flange pipe 2 are the same as each other, and have a common axis P. As shown in FIG. 1B and the 2nd flange part 2B are connected in the sealing state via the ring-shaped gasket G pinched | interposed between these. At that time, the two flange portions 1B and 2B are attracted to each other via the gasket G by the attracting means M, and the first seal end t1 and the gasket formed on the end surface of the first flange portion 1B by this attracting action. The fitting seal portion 3 is formed by fitting with each other between the one end face of G and between the second seal end t2 formed on the end face of the second flange portion 2B and the other end face of the gasket G. The

  In the connection part of both flange piping shown in FIG. 2, the 1st seal end part t1 formed in the end surface of the 1st flange part 1B, and the 2nd seal end part t2 formed in the end surface of the 2nd flange part 2B Are the same structure, only the first seal end t1 will be described, and the second seal end t2 will be denoted by the same reference numeral and the description thereof will be omitted. The first seal end t <b> 1 is formed on the outer diameter side portion of the opening end of the fluid passage 4 on the end face of the first flange portion 1 </ b> B that opens the fluid passage 4 so as to be open outwardly concentrically with the fluid passage 4. It is constituted by an annular groove 6. In addition, the first seal end t1 has a taper-shaped taper that is widened toward the inner periphery of the tip of the annular first joint end 5 formed between the inner diameter portion of the annular groove 6 and the fluid passage 4. A peripheral surface 5a is formed. The annular groove 6 is formed in a shape having a deep cross-sectional rectangle in the direction of the axis P of the fluid passage 4 at a position relatively close to the outer diameter side from the fluid passage 4, and an inner peripheral surface 6a thereof is a first joint end portion. 5 also serves as an outer peripheral surface.

  As shown in FIGS. 2 and 4, the gasket G is formed in a ring shape having a circular fluid passage 9 having the same diameter as the fluid passage 4 in the center, and is open at one end face facing the end face of the first flange portion 1B. An annular protrusion 8 that fits into the annular groove 6 of the first seal end t1 is formed on the outer diameter side portion of the fluid passage 9 to be opened, and the fluid passage 9 opens to the other end surface facing the end surface of the second flange portion 2B. An annular protrusion 8 that fits in the annular groove 6 of the second seal end t2 is formed on the outer diameter side portion of the second seal end portion t2. Further, an annular second joint end portion 7 is formed between the annular projection 8 on the one end surface and the other end surface of the gasket G and the fluid passage 9, and the outer peripheral surface of the distal end portion of the second joint end portion 7 is A tapered outer peripheral surface 7a that comes into contact with the tapered inner peripheral surface 5a of the first joint end portion 5 is tapered to be tapered. The annular protrusion 8 is formed in a shape having a long rectangular cross section in the direction of the axis P of the fluid passage 9, and the protruding length is set to be slightly shorter than the depth of the annular groove 6. Between the 2nd junction end part 7 and the cyclic | annular protrusion 8, it is the cyclic | annular trough part which expands ahead, and it has the structure which the 1st junction end part 5 fits into this trough part.

  As shown in FIG. 2, the fitting seal portions 3 are formed by fitting the annular grooves 6 and 6 of the first and second seal end portions t1 and t2 and the annular projections 8 and 8 on both end faces of the gasket G, respectively. Is done. In this case, if the thickness in the free state of the annular protrusion 8, that is, the radial dimension is set to a value larger than the groove width in the free state of the annular groove 6, that is, the radial dimension, the annular groove is formed by the attracting means M described later. The fitting seal portion 3 formed by fitting the ring 6 and the annular protrusion 8 to each other is configured such that both the inner diameter side peripheral surface 6a and the outer diameter side peripheral surface 6b of the annular groove 6 and the annular protrusion 8 are pressed in the radial direction. Primary and secondary seal portions S1 and S2. However, the fitting seal portion 3 is preferably formed so as to satisfy both the primary and secondary seal portions S1 and S2 in terms of enhancing the sealing performance, but only the primary seal portion S1 or the secondary seal portion 3 It may be formed so as to satisfy only the seal portion S2.

At least the first flange portion 1B of the first flange pipe 1, the at least second flange portion 2B of the second flange pipe 2, and the gasket G are all formed of a fluorine-based resin such as PFA or PTFE, and both flange pipes The diameters d1 and d2 of the fluid passages 1 and 2 and the diameter d3 of the gasket G are set to the same value. For example, the first flange pipe 1 (and second) formed by fixing and integrating a tubular portion 1A formed of a material other than fluororesin such as metal, non-ferrous metal, and PE resin and a first flange portion 1B made of fluororesin. It is also possible to use flange piping 2). In Reference Example 1, both flange portions 1B and 2B are the same, and the gasket G is formed symmetrically, but this is not restrictive.

  Pulling means M is provided across the first and second flange pipes 1 and 2, and the pulling means M pulls the first flange portion 1 </ b> B and the second flange portion 2 </ b> B toward each other via the gasket G. It is configured so that the drawn state can be maintained. When the flanges 1B and 2B are pulled toward each other via the gasket G by the pulling means M, first, the annular groove 6 and the annular protrusion 8 are fitted, and most of them are fitted. Then, the taper inner peripheral surface 5a and the taper outer peripheral surface 7a come into contact with each other. When the taper inner peripheral surface 5a and the taper outer peripheral surface 7a are in strong pressure contact and the approaching movement of both flange portions 1B and 2B is stopped, the space between the annular groove 6 and the annular protrusion 8 in the direction of the axis P , And the outer diameter portion 1g from the annular groove 6 on the end face of the first flange portion 1B and the axial center P direction of the outer diameter portion 10 from the annular protrusion 8 of the gasket G, and the annular end face of the second flange portion 2B. A gap is set between each of the protrusions 8 between the outer diameter portion 2g and the outer diameter portion 10 of the gasket G in the axial center P direction. That is, a gap is provided between the outer diameter portions 1g, 10 and 2g so that the tapered inner peripheral surface 5a and the tapered outer peripheral surface 7a are in contact with each other. Thereby, an effective sealing function at the primary and secondary seal portions S1 and S2 in the fitting seal portion 3 by fitting the annular groove 6 and the annular protrusion 8 is obtained, and the tapered inner peripheral surface 5a and the tapered outer peripheral surface are obtained. In the tertiary seal portion S3 formed between the fluid passages 7a and 7a, there is no gap between the fluid passages 4 and 4 and the fluid passages 9 having the same diameter so that the liquid can be kept clean. It can flow.

  As shown in FIGS. 1 to 3, the attracting means M is composed of a total of four parts including two sets of split rings 25, 25 and a pair of cylindrical nuts 22, 23. The first split ring 25 fitted on the first flange pipe 1 has an outer diameter larger than that of the first flange part 1B, and the first flange part in the direction of the axis P of the first and second flange pipes 1 and 2 It is fitted on the tubular portion 1A of the first flange pipe 1 so as to interfere with 1B, and is composed of a split ring that is divided into two or more than three. The first cylindrical nut 22 has an inward flange 24 having an opening 24a that allows passage of the first flange portion 1B and interferes with the first split ring 25 in the axial center P direction at one end portion. The cylindrical nut is formed and has a male screw portion 22n formed on the outer periphery of the other end.

  The second split ring 25 fitted on the second flange pipe 2 has an outer diameter larger than that of the second flange part 2B and also interferes with the second flange part 2B in the axial center P direction. The tubular portion 2A is externally fitted, and is constituted by a split ring that is divided into two or more than three. The second split ring 25 is the same component as the first split ring 25. The second cylindrical nut 23 is allowed to pass through the second flange portion 2B, and an inward flange 24 having an opening 24a that interferes with the second split ring 25 in the axial center P direction is provided at one end portion. The cylindrical nut is formed and formed with a female screw portion 23n that can be screwed to the male screw portion 22n on the inner periphery of the other end portion. That is, the diameter of the second cylindrical nut 23 is larger than the diameter of the first cylindrical nut 22. Then, the first flange portion 1B and the second flange portion 2B are connected to each other via the gasket G by the tightening operation between the cylindrical nuts 22 and 23 by screwing the male screw portion 22n and the female screw portion 23n. It is configured to be drawn in the approaching direction and to be able to maintain the drawn state (see FIG. 3).

  The opening 24a of the inward flange 24 of each cylindrical nut 22, 23 is set to a minimum inner diameter dimension sufficient to allow the passage of the flange portions 1B, 2B. The outer diameter of each split ring 25 is set to be slightly smaller than the inner diameter of the inner diameter portion 22a so that it can enter the inner diameter portion 22a of the first cylindrical nut 22, and the inner diameter is each tubular shape. It is set to the minimum dimension that allows the parts 1A and 2A to be fitted externally. A portion of the second cylindrical nut 23 adjacent to the inward flange 24 has a smaller diameter than the female screw portion 23n and the inner diameter portion 23a connected to the inner screw portion 23n in order to closely fit the second split ring 25 therein. An inner peripheral surface portion 23m is formed.

  A portion adjacent to the inward flange 24 in the inner diameter portion 22a of the first cylindrical nut 22 is slidable in the axial direction on the first split mold ring 25, and the width dimension of the first split ring 25 is set. An inner peripheral surface portion 22m having a length in the axial center P direction to cover is formed on a flat inner peripheral surface concentric with the fluid passage 4. The inner peripheral surface portion 23 m of the second cylindrical nut 23 described above is also formed on a flat inner peripheral surface concentric with the fluid passage 4. That is, the inner peripheral surface portion 22m that is the inner back portion of the inner diameter portion 22a of the first cylindrical nut 22 is formed on a flat inner peripheral surface concentric with the fluid passage 4, and the inner diameter of the inner peripheral surface portion 22m is While the fitting tolerance is set to be slightly larger than the outer diameter of the first split ring 25 formed in a rectangular cross section, the inner peripheral surface portion 23m of the second cylindrical nut 23 is connected to the fluid passage 4. Dimensionally set to a fitting tolerance state in which the inner peripheral surface portion 23m is concentrically flat on the outer peripheral surface and the inner diameter of the inner peripheral surface portion 23m is slightly larger than the outer diameter of the first split ring 25 formed in a rectangular cross section. Has been. In addition, the inner diameter of each split ring 25 is set to be approximately the same as the diameter of the root of each flange portion 1B, 2B in each tubular portion 1A, 2A so as to come into surface contact with each flange portion 1B, 2B.

  As a result, when the first and second cylindrical nuts 22 and 23 are screwed together and the respective cylindrical nuts 22 and 23 are screwed, the split rings 25 and 25 are tilted. It is possible to prevent the inconvenience that the pressing force in the axis P direction due to the screwing of the first and second cylindrical nuts 22 and 23 is not transmitted well to the flange portions 1B and 2B. The flange portions 1B and 2B are pushed to each other, so that both flange portions 1B and 2B can be satisfactorily drawn toward each other. That is, the inner peripheral surface portions 22m and 23m of the split ring inner fitting portion adjacent to the inward flange 24 of the cylindrical nuts 22 and 23 are formed on a flat inner peripheral surface concentric with the tubular fluid passage 4, and In the region where the inner diameter of the inner peripheral surface portions 22m, 23m and the outer diameter of the split ring 25 formed in a rectangular cross section are larger than the outer diameter of the split ring 25, the inner diameter of the inner peripheral surface portions 22m, 23m. They are formed with almost the same diameter.

  The operation procedure for connecting and connecting the two flange portions 1B and 2B using the pulling means M is as follows. First, as shown in FIG. 3A, the first cylindrical nut 22 is fitted to the outer periphery of the tubular portion 1A of the first flange pipe 1 through the outer diameter side of the first flange portion 1B. And the 2nd cylindrical nut 23 is fitted in the outer periphery of 2 A of tubular parts of the 2nd flange piping 2 through the outer-diameter side of 2nd flange part 2B. Since each cylindrical nut 22 and 23 can pass the 1st and 2nd flange parts 1B and 2B, respectively, these flange pipes 1 and 2 have their other ends already connected to fluid equipment etc. Even in the case, it is possible to externally fit the tubular portions 1A and 2A from the end portions on the flange portions 1B and 2B side without any problem. In addition, if a hexagonal part or a two-sided width part for turning operation with a spanner tool or the like is formed at the inward flange side end of each cylindrical nut 22, 23, it is convenient in tightening and disassembling operation. .

  Next, as shown in FIG. 3 (b), the first split ring 25 is passed between the first flange 1B and the tip of the first cylindrical nut 22 and is in contact with the side surface of the first flange portion 1B. The second flange portion is fitted on the outer periphery of the tubular portion 1A of the first flange pipe 1 and the second split ring 25 is passed between the second flange 2B and the tip of the second cylindrical nut 23. It fits on the outer periphery of the tubular portion 2A of the second flange pipe 2 in a state of abutting against the side surface of 2B. At this time or before that, the gasket G may be attached to the end face of one of the flange portions 1B, 2B through temporary fitting between the annular protrusion 8 and the annular groove 6. Next, the two flange portions 1B and 2B are connected to each other through the gasket G, and the first cylindrical nut 22 and the second cylindrical nut 23 are screwed together in that state, thereby performing a tightening operation [FIG. 3 (c). By performing the reference, the connection state shown in FIGS. 1 and 2 is obtained.

  The first flange pipe 1 and the second flange pipe 2 are attracted in the direction approaching each other by the attracting means M, and in the connected state, as shown in FIG. G is pressed and clamped. Further, as described above, the annular grooves 6 and 6 on the end surfaces of both flange portions 1B and 2B and the annular protrusions 8 on both end surfaces of the gasket G are press-fitted to form the fitting seal portions 3 and 3. In addition, the taper inner peripheral surface 5a and the taper outer peripheral surface 7a are brought into pressure contact with each other so that the fluid passage 4 of the first flange pipe 1, the fluid passage 9 of the gasket G, and the fluid passage 4 of the second flange pipe 2 are spanned. Therefore, it is possible to exhibit a good sealing function of allowing the liquid to flow without leakage and liquid accumulation.

  If the radial dimension of the annular protrusion 8 is slightly larger than the radial dimension of the annular groove 6 and is inserted in a press-fit state, the inner diameter side peripheral surface 6a and the outer diameter side peripheral surface 6b and the annular protrusion 8 are formed. A highly effective primary seal portion S1 and secondary seal portion S2 are obtained by being pressed strongly in the radial direction. In this case, the outer diameter side portion of the annular groove 6 of both flange portions 1B and 2B has sufficient rigidity due to sufficient thickness (diameter dimension), but the inner diameter side portion of the annular groove 6 is thin (radial direction). Since only the first joint end 5 (which is short in dimension) is not in a rigid state, the first joint end 5 is inclined and deformed toward the inner diameter side as the annular protrusion 8 is press-fitted into the annular groove 6. The diameter of the tubular fluid passage 4 may be partially reduced.

  However, as shown in FIG. 2, the second joint end portion 7 of the gasket G is positioned on the inner diameter side of the first joint end portion 5 in a state where the taper inner peripheral surface 5a and the taper outer peripheral surface 7a are in close contact with each other. Therefore, the presence of the second joint end portion 7 has an advantage that the deformation of the first joint end portion 5 toward the inner diameter side (diameter reduction deformation) is prevented. That is, not only the function as the tertiary seal portion S3 by the press contact between the taper inner peripheral surface 5a and the taper outer peripheral surface 7a is obtained, but the rigidity of the first joint end portion 5 is compensated for and the tubular fluid passages 4, The diameter of 4 is regulated so as not to change, and a reduction in contact pressure between the primary seal portion S1 and the secondary seal portion S2 can be prevented to effectively exhibit excellent sealing performance.

  Although the relationship between the annular groove 6 and the annular protrusion 8 has been described a little earlier, as shown in FIG. 5, the diameter width (groove width) 6w of the annular groove 6 in the free state and the diameter of the annular protrusion 8 in the free state. The diameter width (groove width) of the annular groove 6 is made smaller than the diameter width (thickness) of the annular protrusion 8 so that the width (thickness) 8w becomes 6w × (1.05 to 1.5) = 8w. It is preferable that the fitting seal portion 3 is formed by press-fitting both. As a result, the fitting seal portion 3 formed by fitting the annular groove 6 and the annular projection 8 can exhibit extremely good sealing performance without leakage. In addition, as described above, in this seal connection state, the recess depth of the annular groove 6 is set so that a gap in the axial center P direction is formed between the annular groove 6 and the annular protrusion 8. If the value is slightly larger than the protruding amount, it is advantageous in that the taper inner peripheral surface 5a and the taper outer peripheral surface 7a are reliably pressed against each other.

  As shown in FIG. 5, the relationship between the taper inner peripheral surface 5a and the taper outer peripheral surface 7a is such that when both flange portions 1B and 2B are moved relatively close to each other by movement in the axis P direction, Abutting on the tapered inner peripheral surface 5a of the first joint end portion 5 of the first flange portion 1B (or the second joint end portion 5 of the second flange portion 2B) from the tip end side of the taper outer peripheral surface 7a at the joint end portion 7. The inclination angle α of the taper outer peripheral surface 7a should be 1 to 30 degrees, preferably 3 to 10 degrees smaller than the inclination angle θ of the taper inner peripheral surface 5a (1 to 30 degrees + α = θ). Further, after tightening the flange portions 1B and 2B by the first and second cylindrical nuts 22 and 23, a gap is provided between the tapered outer peripheral surface 5a except for the tip portion of the tapered outer peripheral surface 7a, and A tertiary seal portion S3 that increases the surface pressure between the tip end portion of the tapered outer peripheral surface 7a and the tapered inner peripheral surface 5a can be formed, which is preferable.

  As shown in FIG. 5, the annular groove 6 may be formed on a tapered surface 6 a whose opening side end portion is inclined so as to be expanded so that the annular protrusion 8 can easily enter. As shown in FIG. 5, the tip corner 8 a of the annular protrusion 8 may have a shape that is cut obliquely by chamfering or the like in order to easily enter the annular groove 6. The corner portion s between the annular protrusion 8 and the seal end portion 7 may be subjected to curved surface processing so that the shape thereof smoothly changes as shown in FIG. Further, the tip end portion 7b of the seal end portion 7 may be chamfered so as not to have a pin angle as shown in FIG. The first and second cylindrical nuts 22 and 23 and the first and second split rings 25 and 25 are made of various materials such as non-ferrous metals such as metals and aluminum alloys in addition to fluororesins such as PFA and PTFE. It is possible to make it.

By the way, as shown in the second flange pipe 2 in FIG. 2, the outer diameter portion 2k of the tubular portion 2A on which the split ring 25 is fitted is formed on the flat outer peripheral surface concentrically with the tubular fluid passage 4, In addition, the outer diameter of the outer diameter portion 2k and the inner diameter of the split ring 25 are formed to be substantially the same in a region where the inner diameter of the split ring 25 is larger than the outer diameter of the outer diameter portion 2k. This is more convenient. If this configuration is adopted, the split ring 25 and the tubular portion 2A can be smoothly moved relative to each other without being twisted during the tightening operation of the cylindrical nut 23, and both flange portions 1B, 2B by the pulling means M can be moved. The function of efficiently performing the pulling movement is promoted. When combined with a fitting structure having a fitting tolerance between the inner peripheral surface portion 23m of the second cylindrical nut 23 and the outer diameter portion of the split ring 25, the follow-up of the split ring 25 by the screwing of the cylindrical nut 23 is performed. The movement is further smoothed, and the connection means can be firmly connected without leakage while easily operating the attracting means M. Naturally, the above-described configuration can be applied to the first flange pipe 1.
(Reference Example 2 )

As shown in FIG. 6, the connection structure between the flanged pipes according to Reference Example 2 is basically the same structure as the connection structure between the flanged pipes according to Reference Example 1 shown in FIG. It is. In this case, the attracting means M is attached to the flange portions 1B and 2B in a state along the outer diameter side portions of the first and second flange portions 1B and 2B and the axis P direction of the first and second flange portions 1B and 2B. It comprises a bolt 41 and a nut 42 that can pass through the formed holes 1h and 2h.

  Bolts 41 and nuts 42 constituting the pulling means M are arranged at a plurality of locations (for example, three locations) around the flange portions 1B and 2B at equal angles, and the first and second flange portions 1B, 1B, It is configured to be able to draw 2B in a direction approaching each other and to be able to maintain the drawing state. That is, by tightening the bolt 41 and the nut 42, the first and second flange portions 1B and 2B are moved closer to each other via the gasket G, and the annular grooves 6 and 6 on the end surfaces of both flange portions 1B and 2B , The fitting operation of the first and second seal end portions t1 and t2 by press fitting the annular projections 8 on both end faces of the gasket G, and thereby the first joint end portion 5 and the second joint end The primary seal seal S3 and the secondary seal seal S2 are press-fitted between the annular groove 6 and the annular projection 8 so that the tertiary seal portion S3 is formed with the portion 7 without any gap. Thus, it is possible to maintain the seal connection state in which the fitting seal portion 3 is formed.

FIG. 7 shows a connection structure between flange pipes according to the first embodiment. In the connection structure between the flange pipes according to the reference example 1, the first and second seal end portions t1 and t2 are formed by the annular groove 6, and the annular protrusions 8 are formed on both end faces of the gasket G, respectively. As in the first embodiment shown in FIG. 7, the first and second seal end portions t1 and t2 may be formed by the annular protrusions 18, and the annular grooves 16 may be formed on both end faces of the gasket G2.

That is, in the first embodiment, as shown in FIGS. 7 and 8, the annular groove 16 is formed on the outer diameter portion of the opening end portion of the fluid passage 9 that opens at both end faces of the gasket G , concentrically with the fluid passage 9. It is formed in an open direction. Further, a tapered inner circumferential surface 15 a is formed so as to be widened toward the inner circumferential end of the annular first joint end 15 formed between the inner diameter portion of the annular groove 16 and the fluid passage 9. The annular groove 16 is formed in a shape having a rectangular cross section extending in the direction of the axis P of the fluid passage 9, and the inner peripheral surface 16 a also serves as the outer peripheral surface of the first joint end 15.

On the other hand, the first of the first and second flange pipe 1, the second flange portion 1B, first and second seal end t1, t 2 is formed on each end face of the 2B are first and second flange portions 1B, Fitting formed integrally with the outer diameter side portion of the open end portion of the tubular fluid passage 14 on each end face of 2B so as to fit concentrically with the fluid passage 14 and into the annular groove 16 on the gasket G side. It is constituted by the protrusion 18. Further, the first and second seal end portions t1 and t2 are formed on the tip outer peripheral surface of the annular second joint end portion 17 formed between the annular protrusion 18 and the fluid passage 14, and on the tapered inner peripheral surface 15a. The abutting tapered outer peripheral surface 17a is tapered to form a tapered shape. The annular protrusion 18 is formed in a shape having a long cross-sectional rectangle in the direction of the axis P of the fluid passage 14, and the protruding length is set to be slightly shorter than the depth of the annular groove 16. Between the 2nd junction end part 17 and the cyclic | annular protrusion 18, it is the cyclic | annular valley part which expands, and it has the structure which the 1st junction end part 15 fits in this valley part.

Further, in order to obtain the functions of the primary and secondary seal portions S1 and S2 effective in the seal connection state in which the annular protrusion 18 having a larger radial dimension is press-fitted into the annular groove 16 of the gasket G, On the outer diameter side of the groove 16, an annular outer peripheral projection 19 having a sufficiently large radial dimension and rigidity is formed. On the other hand, an annular large groove 20 is formed on the outer diameter side of the annular projection 18 constituting the first and second seal end portions t1 and t2 for fitting the outer circumferential projection 19 with a gap.

Also in the first embodiment, the inner circumferential surface of the taper is designed to function as the tertiary seal portion S3 in the seal connection state in which the annular protrusion 18 is fitted into the annular groove 16 to form the primary seal portion S1 and the secondary seal portion S2. 15a and the taper outer peripheral surface 17a are in contact with each other between the annular groove 16 and the annular protrusion 18 and between the outer peripheral protrusion 19 and the large annular diameter groove 20 in the direction of the axial center P so as to ensure contact with each other. Is set to The pulling means M used in the connection structure according to the first embodiment has the same structure as that of the reference example 1 so that the first and second flange portions 1B and 2B can be pulled toward each other. And it is comprised so that a drawing state can be maintained, and the same code | symbol as the drawing means M by the reference example 1 is attached | subjected to the corresponding location.
(Reference Example 3)

The connection structure between the flange pipes according to the reference example 3 is different from the connection structure between the flange pipes according to the reference example 1 in the drawing means M. That is, instead of the drawing means M shown in FIG. 2 consisting of four parts of a pair of cylindrical nuts 22, 23 and two sets of split rings 25, 25, as shown in FIG. A cylindrical nut 21 having a structure in which the outer peripheral female screw portion of the first cylindrical nut 22 is changed to an inner peripheral male screw portion, a pair of split rings 25, and a first flange portion 1B (or a second flange 2B). The pulling means M is composed of a female screw portion 1n formed on the outer periphery of the pipe. The pulling means M in the connection structure (see FIG. 10) according to Reference Example 4 to be described later is replaced with a connection structure between the flange pipes 1 and 2. It is used. With such a configuration, the second cylindrical nut 23 and the pair of split rings 25 can be omitted by forming the outer peripheral screw on one of the flange portions 1B, 2B. The disassembly is facilitated and the cost can be improved.

Next, referring to FIGS. 9 to 15, reference embodiments and embodiments of the connection structure between the flange pipe and the fluid device will be described as Reference Examples 4, 5, Example 2 and Reference Examples 6 , 7 . There are various fluid devices such as a pump, a valve, an accumulator, and a storage container. In the following, a manual stop valve will be described as an example.
(Reference Example 4)

As shown in FIG. 9, the connection structure between the flange piping and the fluid device according to the reference example 4 is configured at a connection portion between the manual stop valve 31 and the second flange piping 2. That is, at the end of the tubular portion 2A having the tubular fluid passage 4, the flange portion 2B of the flange pipe 2 having a flange portion 2B having a diameter larger than that of the tubular portion 2A and the fluid supply having the tubular fluid passage 34 are provided. A ring-shaped gasket G interposed between the flange portion 2B and the fluid supply / exhaust port portion 31b is connected to the fluid supply / exhaust port portion 31b of a manual stop valve (an example of a fluid device) 31 provided with an exhaust port portion 31b. This is a connection structure that communicates through the connection. The manual stop valve 31 includes a valve body 31H, a rotation operation unit 31K, a pair of fluid supply / discharge ports 31a and 31b, and the like.

  As an example, as shown in FIG. 10, the manual stop valve 31 and the flange pipe 2 seal the fluid supply / discharge port portion 31 b on the out side of the manual stop valve 31 and the flange portion 2 </ b> B through a gasket G. Communication connection in the state. At this time, the out-side fluid supply / discharge port portion 31b and the flange portion 2B are attracted to each other via the gasket G by the attracting means M, and are formed on the end surface of the fluid supply / discharge port portion 31b by this attracting action. The first seal end t1 and one end surface of the gasket G, and the second seal end t2 formed on the end surface of the flange portion 2B and the other end surface of the gasket G are fitted to each other. A seal portion 3 is formed.

  The first seal end t1 formed on the end surface of the fluid supply / exhaust port portion 31b shown in FIG. 10 and the second seal end t2 formed on the end surface of the flange portion 2B have the same structure and the second seal. Since the end portion t2 is the same as that of the second flange portion 2B shown in FIG. 2, only the first seal end portion t1 will be described, and the second seal end portion t2 will be assigned the same or corresponding symbol. The description is omitted. The first seal end t1 is formed on the outer diameter side portion of the opening end of the fluid passage 34 on the end face of the fluid supply / exhaust port 31b that opens the tubular fluid passage 34, and is open outwardly concentrically with the fluid passage 34. The annular groove 6 is formed. In addition, the first seal end t1 has a tapered taper that is widened toward the inner peripheral end of the annular first joining end 5 formed between the inner diameter portion of the annular groove 6 and the fluid passage 34. A peripheral surface 5a is formed. The annular groove 6 is formed in a shape exhibiting a deep cross-sectional rectangle in the direction of the axis P of the fluid passage 34 at a position relatively close to the outer diameter side from the fluid passage 34, and the inner peripheral surface 6a thereof is a first joint end portion. 5 also serves as an outer peripheral surface.

  As shown in FIGS. 10 and 4, the gasket G is formed in a ring shape having a tubular fluid passage 9 having the same diameter as the fluid passage 34 of the fluid supply / exhaust port portion 31b at the center, and the out-side fluid supply / discharge port portion 31b. An annular projection 8 that fits into the annular groove 6 of the first seal end t1 is formed on the outer diameter side portion of the fluid passage 9 that opens to one end face that faces the other end face, and faces the end face of the flange portion 2B. An annular protrusion 8 that fits into the annular groove 6 of the second seal end t2 is formed on the outer diameter side portion of the fluid passage 9 that opens to the end face. Further, an annular second joint end portion 7 is formed between the annular projection 8 on the one end surface and the other end surface of the gasket G and the fluid passage 9, and the outer peripheral surface of the distal end portion of the second joint end portion 7 is A tapered outer peripheral surface 7a that comes into contact with the tapered inner peripheral surface 5a of the first joint end portion 5 is tapered to be tapered. The annular protrusion 8 is formed in a shape having a long rectangular cross section in the direction of the axis P of the fluid passage 9, and the protruding length is set to be slightly shorter than the depth of the annular groove 6. Between the 2nd junction end part 7 and the cyclic | annular protrusion 8, it is the cyclic | annular trough part which expands ahead, and it has the structure which the 1st junction end part 5 fits into this trough part.

  As shown in FIG. 10, the fitting seal portions 3 are formed by fitting the annular grooves 6 and 6 of the first and second seal end portions t1 and t2 and the annular projections 8 and 8 on both end faces of the gasket G, respectively. Is done. In this case, if the thickness in the free state of the annular protrusion 8, that is, the radial dimension is set to a value larger than the groove width in the free state of the annular groove 6, that is, the radial dimension, the annular groove is formed by the attracting means M described later. The fitting seal portion 3 formed by fitting the ring 6 and the annular protrusion 8 to each other is configured such that both the inner diameter side peripheral surface 6a and the outer diameter side peripheral surface 6b of the annular groove 6 and the annular protrusion 8 are pressed in the radial direction. Primary and secondary seal portions S1 and S2. However, the fitting seal portion 3 is preferably formed so as to satisfy both the primary and secondary seal portions S1 and S2 in terms of enhancing the sealing performance, but only the primary seal portion S1 or the secondary seal portion 3 It may be formed so as to satisfy only the seal portion S2.

  At least the out-side fluid supply / exhaust port portion 31b of the manual stop valve 31, the at least flange portion 2B of the flange pipe 2, and the gasket G are all made of a fluorine-based resin such as PFA or PTFE. The diameter d1 of the tubular fluid passage 34 of the valve 31, the diameter d2 of the tubular fluid passage 4 of the flange pipe 2, and the diameter d3 of the tubular fluid passage 9 of the gasket G are set to the same value.

  An attraction means M is provided across the manual stop valve 31 and the flange pipe 2, and the attraction means M causes the out-side fluid supply / discharge port portion 31 b of the manual stop valve 31 and the flange portion 2 B of the flange pipe 2 to be mutually connected. It draws in the direction which approaches via the gasket G, and it is comprised so that this drawn state can be maintained. When the fluid supply / exhaust port portion 31b and the flange portion 2B are pulled toward each other via the gasket G by the pulling means M, first, the annular groove 6 and the annular protrusion 8 are fitted to each other. After the portions are fitted, the tapered inner peripheral surface 5a and the tapered outer peripheral surface 7a come into contact with each other. When the tapered inner peripheral surface 5a and the tapered outer peripheral surface 7a are in strong pressure contact with each other and the fluid supply / exhaust port portion 31b and the flange portion 2B stop moving toward each other, the shaft between the annular groove 6 and the annular projection 8 is stopped. Between the center P direction, between the outer diameter portion 31g from the annular groove 6 on the end surface of the fluid supply / discharge port portion 31b, between the annular projection 8 of the gasket G and the outer diameter portion 10, and between the flange portion 2B. From the annular projection 8 on the end face, a gap is set between the outer diameter portion 2g and the outer diameter portion 10 of the gasket G in the axial center P direction. That is, a gap is provided between the outer diameter portions 31g, 10 and 2g so that the tapered inner peripheral surface 5a and the tapered outer peripheral surface 7a are in contact with each other. Thereby, an effective sealing function at the primary and secondary seal portions S1 and S2 in the fitting seal portion 3 by fitting the annular groove 6 and the annular protrusion 8 is obtained, and the tapered inner peripheral surface 5a and the tapered outer peripheral surface are obtained. In the tertiary seal portion S3 formed between the fluid passages 7a and 7a, there is no gap between the fluid passages 34 and 4 and the fluid passages 9 having the same diameter so that the liquid is kept clean. It can flow.

  As a specific example of the attracting means M, for example, as shown in FIGS. 9 and 10, it is screwed into a male screw 31 n formed on the outer peripheral portion of the out-side fluid supply / discharge port portion 31 b of the manual stop valve 31. It consists of a cylindrical nut 21 provided with a free female screw 21n, and a split ring 25 that is split into two or more than three that interferes with the flange portion 2B of the flange pipe 2 in the direction of the axis P thereof. By tightening the cylindrical nut 21 to the male screw 31n of the mouth portion 31b, the fluid supply / discharge port portion 31b and the flange portion 2B can be pulled toward each other via the gasket G, and the pulled state is maintained. It is configured to be maintainable.

  The opening portion 24a of the inward flange 24 of the cylindrical nut 21 is set to a minimum inner diameter dimension sufficient to allow passage of the flange portion 2B, and the outer diameter of the split ring 25 is set to the cylindrical nut 21. The inner screw 21n and the inner diameter portion 21a connected to the inner screw 21n and the inner diameter portion 21a are set to be slightly smaller than the inner diameter, and the inner diameter is set to a minimum dimension that allows the tube portion 2A to be fitted externally. In addition, although illustration is abbreviate | omitted, you may employ | adopt the close fitting structure which has the fitting tolerance shown in FIG. 2 in the fitting part of the outer diameter of the tubular part 2A, and the inner diameter of the split ring 25.

  Further, an axial center that is slidable in the axial direction on the split ring 25 and covers the width of the split ring 25 between the inner back end portion of the female screw 21n and the flange portion 2B in the cylindrical nut 21. An inner peripheral surface portion 21 m having a length in the P direction is formed in a flat state concentrically with the fluid passage 4. That is, the inner diameter portion 21a between the female screw 21n of the cylindrical nut 21 and the inward flange 24 is formed on a flat inner peripheral surface concentric with the fluid passage 4, and the inner diameter portion 21a has a rectangular cross section. The inner peripheral surface portion 21m is dimensioned to a fitting tolerance that is slightly larger than the outer diameter of the formed split ring 25. On the other hand, as described above, the outer peripheral portion of the tubular portion 2A adjacent to the flange portion 2B is formed in a flat outer peripheral surface concentrically with the fluid passage 4, and the outer diameter of the outer peripheral surface and the inner diameter of the split ring 25 And may be formed to have substantially the same diameter. As a result, when the cylindrical nut 21 is screwed, the split ring 25 is inclined, and the pressing force in the axis P direction due to the screwing of the cylindrical nut 21 on the flange portion 2B is good. The inconvenience of not being transmitted can be prevented, and the flange portion 2B can be effectively pushed, and the fluid supply / exhaust port portion 31b and the flange portion 2B can be satisfactorily drawn toward each other.

  The operation procedure for connecting and connecting the fluid supply / exhaust port portion 31a and the flange portion 2B using the pulling means M is as follows. First, as shown to Fig.11 (a), the cylindrical nut 21 is fitted to the outer periphery of 2 A of tubular parts of the flange piping 2 through the flange part 2B. Next, as shown in FIG. 11B, the split ring 25 is fitted on the tubular portion 2 </ b> A through the gap between the flange portion 2 </ b> B and the tip of the tubular nut 21. At this time or before that, the gasket G may be attached to the end surface of the fluid supply / exhaust port portion 31b or the end surface of the flange portion 2B through provisional fitting between the annular protrusion 8 and the annular groove 6. Next, the fluid supply / exhaust port portion 31b and the flange portion 2B are attached to each other via the gasket G, and the cylindrical nut 21 is slid in that state, and then screwed onto the male screw 31n of the fluid supply / discharge port portion 31b. By performing the tightening operation [see FIG. 11C], the connection states shown in FIGS. 9 and 10 are obtained.

  The manual stop valve 31 and the flange pipe 2 are drawn toward each other by the drawing means M, and as shown in FIG. 10, in the connected state, the fluid supply / discharge port portion 31b and the flange portion 2B Thus, the gasket G is pressed and clamped. Further, as described above, the annular grooves 6 and 6 on the end surfaces of the fluid supply / exhaust port portion 31b and the flange portion 2B and the annular protrusions 8 on both end surfaces of the gasket G are press-fitted and fitted to the fitting seal portion 3. 3 and the taper inner peripheral surface 5a and the taper outer peripheral surface 7a are brought into pressure contact with each other, whereby the fluid passage 34 of the fluid supply / discharge port 31b, the fluid passage 9 of the gasket G, and the fluid passage of the flange pipe 2 A good sealing function is exhibited in which the liquid can flow between the four without leakage and liquid accumulation.

  If the radial dimension of the annular protrusion 8 is slightly larger than the radial dimension of the annular groove 6 and is inserted in a press-fit state, the inner diameter side peripheral surface 6a and the outer diameter side peripheral surface 6b and the annular protrusion 8 are formed. A highly effective primary seal portion S1 and secondary seal portion S2 are obtained by being pressed strongly in the radial direction. In this case, the outer diameter side portion of the annular groove 6 between the fluid supply / discharge port portion 31b and the flange portion 2B has sufficient rigidity (diameter dimension), but the inner diameter side portion of the annular groove 6 has a thickness. Since the first joint end 5 is thin (short in radial direction) and not in a rigid state, the first joint end 5 has an inner diameter as the annular projection 8 is press-fitted into the annular groove 6. There is a fear that the diameter of the tubular fluid passage 4 may be partially reduced due to tilting to the side.

  However, as shown in FIG. 10, the second joint end 7 of the gasket G is positioned on the inner diameter side of the first joint end 5 with the taper inner peripheral surface 5a and the taper outer peripheral surface 7a being in close contact with each other. Therefore, the presence of the second joint end portion 7 has an advantage that the deformation of the first joint end portion 5 toward the inner diameter side (diameter reduction deformation) is prevented. That is, not only the function as the tertiary seal portion S3 by the press contact between the taper inner peripheral surface 5a and the taper outer peripheral surface 7a is obtained, but also the lack of rigidity of the first joint end portion 5 is compensated for and the fluid passages 34, 4 By restricting the diameter so as not to change, the contact pressure between the primary seal portion S1 and the secondary seal portion S2 is prevented from being lowered, and excellent sealing performance can be effectively exhibited.

  Regarding the relationship between the annular groove 6 and the annular protrusion 8, as shown in FIG. 5, the radial width (groove width) 6w in the free state of the annular groove 6 and the radial width (thickness) 8w in the free state of the annular protrusion 8 are as follows. , 6w × (1.05-1.5) = 8w so that the diameter width (groove width) of the annular groove 6 is smaller than the diameter width (thickness) of the annular protrusion 8, and the two are press-fitted together. Thus, it is preferable to form the fitting seal portion 3. As a result, the fitting seal portion 3 formed by fitting the annular groove 6 and the annular projection 8 can exhibit extremely good sealing performance without leakage. In addition, as described above, in this seal connection state, the recess depth of the annular groove 6 is set so that a gap in the axial center P direction is formed between the annular groove 6 and the annular protrusion 8. If the value is slightly larger than the protruding amount, it is advantageous in that the taper inner peripheral surface 5a and the taper outer peripheral surface 7a are reliably pressed against each other.

  As shown in FIG. 5, the relationship between the taper inner peripheral surface 5 a and the taper outer peripheral surface 7 a is such that when the fluid supply / exhaust port portion 31 b and the flange portion 2 </ b> B are relatively moved by movement in the axis P direction, Tapered inner peripheral surface so that the fluid supply / discharge port portion 31b and the taper inner peripheral surface 5a of the first joint end portion 5 of the flange portion 2B come into contact with the tapered outer peripheral surface 7a of the second joint end portion 7 of the gasket G from the front end side. The inclination angle α of the taper outer peripheral surface 7a should be 1 to 30 degrees, preferably 3 to 10 degrees smaller than the inclination angle θ of 5a (1 to 30 degrees + α = θ). Further, even after the cylindrical nut 22 is tightened, the gap between the tapered outer peripheral surface 5a and the tapered inner peripheral surface 5a except for the tip portion of the tapered outer peripheral surface 7a is provided, so that the surface between the distal end portion of the tapered outer peripheral surface 7a and the tapered inner peripheral surface 5a. The tertiary seal portion S3 that increases the pressure can be formed, which is preferable.

As shown in FIG. 5, the annular groove 6 may be formed on a tapered surface 6 a whose opening side end portion is inclined so as to be expanded so that the annular protrusion 8 can easily enter. As shown in FIG. 5, the tip corner 8 a of the annular protrusion 8 may have a shape that is cut obliquely by chamfering or the like in order to easily enter the annular groove 6. The corner portion s between the annular protrusion 8 and the seal end portion 7 may be subjected to curved surface processing so that the shape thereof smoothly changes as shown in FIG. Further, the tip end portion 7b of the seal end portion 7 may be chamfered so as not to have a pin angle as shown in FIG. The cylindrical nut 21 and the split ring 25 can be made of various materials such as non-ferrous metals such as metals and aluminum alloys in addition to fluororesins such as PFA and PTFE. As the fluid device 31, there are an accumulator, a pump, a heat exchanger and the like in addition to the manual stop valve 31.
(Reference Example 5)

The connection structure between the flange piping and the fluid device according to the reference example 5 is basically the same as the connection structure according to the reference example 4 shown in FIG. 10 except that the drawing means M is different as shown in FIG. . The attracting means M in this case includes an outward flange 31f and a flange portion 2B formed on the outer periphery of the distal end portion of the fluid supply / discharge port portion 31b, and an outward flange 31f and a flange in a state along the axis P direction. It consists of a bolt 41 and a nut 42 which can pass through holes 31h and 2h formed in the portion 2B.

  Bolts 41 and nuts 42 constituting the pulling means M are arranged at equal angles at a plurality of locations (for example, three locations) around the outward flange 31f and the flange portion 2B. 1b and the flange part 2B can be pulled in a direction approaching each other, and the pulled state can be maintained. That is, by tightening the bolt 41 and the nut 42, the fluid device 31 and the flange pipe 2 are moved closer to each other via the gasket G, and the annular grooves 6 on the end surfaces of the fluid supply / discharge port portion 31b and the flange portion 2B are moved. , 6 and the annular projections 8 on both end faces of the gasket G are press-fitted together, and the first and second seal end portions t1, t2 are fitted together, and thereby the first joint end portion 5 and the first joint end portion 5 are The primary and secondary seal portions are formed by press-fitting between the annular groove 6 and the annular protrusion 8 so that the tertiary seal portion S3 is formed between the two joining end portions 7 and the both ends 5 and 7 are press-contacted without gaps. The seal connection state in which the fitting seal portion 3 is formed so that S1 and S2 are generated can be maintained.

FIG. 13 shows a connection structure between a flange pipe and a fluid device according to the second embodiment. In the connection structure according to the reference example 4 , the first and second seal end portions t1 and t2 are formed by the annular groove 6 and the annular protrusions 8 are formed on both end faces of the gasket G, respectively. As in the connection structure according to the second embodiment, the first and second seal end portions t1 and t2 may be formed by the annular protrusions 18 and the annular grooves 16 may be formed on both end faces of the gasket G, respectively.

That is, in the connection structure according to the second embodiment, as shown in FIGS. 13 and 8, concentric with the fluid passage 9 at the outer diameter portion of the open end portion of the tubular fluid passage 9 that opens at both end faces of the gasket G. The annular groove 16 is formed to open outward. Further, a tapered inner circumferential surface 15 a is formed so as to be widened toward the inner circumferential end of the annular first joint end 15 formed between the inner diameter portion of the annular groove 16 and the fluid passage 9. The annular groove 16 is formed in a shape having a rectangular cross section extending in the direction of the axis P of the fluid passage 9, and the inner peripheral surface 16 a also serves as the outer peripheral surface of the first joint end 15.

  On the other hand, the first and second seal end portions t1 and t2 formed on the end surfaces of the fluid supply / discharge port portion 31b of the fluid device 31 and the flange portion 2B of the flange pipe 2 are the fluid supply / discharge port portion 31b and the flange portion 2B. Are formed in a projecting manner so as to be concentric with the fluid passages 34 and 4 and to be fitted into the annular groove 16 on the gasket G side. It is constituted by the fitting protrusion 18. Further, the tapered inner peripheral surface of the first and second seal end portions t1 and t2 is formed on the tip outer peripheral surface of the annular second joint end portion 17 formed between the annular protrusion 18 and the fluid passages 34 and 4. A tapered outer peripheral surface 17a that abuts on 15a is tapered to form a tapered shape. The annular protrusion 18 is formed in a shape having a rectangular cross section that is long in the direction of the axis P of the fluid passages 34, 4, and the protruding length is set to be slightly shorter than the depth of the annular groove 16. Yes. Between the 2nd junction end part 17 and the cyclic | annular protrusion 18, it is the cyclic | annular valley part which expands, and it has the structure which the 1st junction end part 15 fits in this valley part.

  Further, in order to obtain the functions of the primary and secondary seal portions S1 and S2 effective in the seal connection state in which the annular protrusion 18 having a larger radial dimension is press-fitted into the annular groove 16 of the gasket G, On the outer diameter side of the groove 16, an annular outer peripheral projection 19 having a sufficiently large radial dimension and rigidity is formed. On the other hand, an annular large groove 20 is formed on the outer diameter side of the annular protrusion 18 constituting the first and second seal end portions t1 and t2 for fitting the outer peripheral protrusion 19 with a gap.

Also in the second embodiment, the inner circumferential surface of the taper is designed to function as the tertiary seal portion S3 in the seal connection state in which the annular protrusion 18 is fitted in the annular groove 16 to form the primary seal portion S1 and the secondary seal portion S2. 15a and the taper outer peripheral surface 17a are in contact with each other between the annular groove 16 and the annular protrusion 18 and between the outer peripheral protrusion 19 and the large annular diameter groove 20 in the direction of the axial center P so as to ensure contact with each other. Is set to Attracting means M used in the connecting structure according to the second embodiment has been made in view of those same structure of Example 4, can not attracting the direction approaching was how fluid supply and discharge port portion 31b and the flange portion 2B to each other In addition, the attracting state can be maintained, and corresponding portions are denoted by the same reference numerals as the attracting means M according to Reference Example 4 .
(Reference Example 6)

FIG. 14 shows a connection structure between the flange piping and the fluid device according to Reference Example 6 . This discloses another structural example of the attracting means M, and a case where the structure is applied to a connection structure between the manual stop valve 31 and the flange pipe 2 will be described. That is, the pulling means M according to the connection structure of Reference Example 6 includes a female screw portion 23 that can be screwed into a male screw portion 31n formed on the outer peripheral portion of the fluid supply / discharge port portion 31b, and a cylinder having an inward flange 24. And a snap ring 26 that interferes with the flange portion 2B and the cylindrical nut 21 in the direction of the axis P of the fluid supply / discharge port portion 31b and the tubular portion 2A. The fluid supply / discharge port portion 31b and the flange portion 2B come close to each other via the gasket G by the tightening operation by screwing the female screw portion 21n of the cylindrical nut 21 to the male screw portion 31n of the fluid supply / discharge port portion 31b. It is configured to be able to be pulled in the direction and to be able to maintain the pulled state. The snap ring 26 is fitted in the outer circumferential groove 2m formed at the end of the flange portion 2B.

The pulling means M according to the present reference example 6 has a cylindrical nut on the outer periphery of the first flange portion 1B (or the second flange portion 2B) of the first flange pipe 1, as indicated mainly by phantom lines in FIG. By forming the male screw portion 1n that can be screwed into the female screw portion 21n, the present invention can also be applied to the connection structure between the flange pipes 1 and 2 shown in FIG. In this case, the outer diameter of the flange portion 1B where the male screw portion 1n is formed is made larger than the outer diameter of the other flange portion 2B, thereby making the shape simpler than that of the second cylindrical nut 23. A cylindrical nut 21 can be used.
(Reference Example 7)

FIG. 15 shows a connection structure between the flange piping and the fluid device according to the reference example 7 . This discloses a further example of the structure of the pulling means M, and a case where the structure is applied to a connection structure between the manual stop valve 31 and the flange pipe 2 will be described. That is, the pulling means M according to the connection structure of Reference Example 7 includes a cylindrical nut 28 having a female screw portion 28n that can be screwed into a male screw portion 31n formed on the outer peripheral portion of the fluid supply / discharge port portion 31b, and a flange. The split ring 29 interferes with both the part 2B and the flange pipe 2 side end of the cylindrical nut 28 in the axial center P direction. The split ring 29 has a plurality of through holes 29b for bolt insertion, and is fastened with bolts B to the flange pipe 2 side end of the cylindrical nut 28. By tightening the female screw portion 28n formed on the cylindrical nut 28 by screwing the fluid supply / discharge port portion 31b to the male screw portion 31n, the fluid supply / discharge port portion 31b and the flange portion 2B attach the gasket G to each other. It is comprised so that it can be pulled in the direction which approaches via, and a drawing state can be maintained. In addition, although illustration is abbreviate | omitted, you may apply the attracting means M in this reference example 7 to the connection structure of the flange piping 1 and 2. FIG.

Other reference example of that, as shown mainly in phantom in FIG. 2, the connecting structure between a fluid device 31 and the flange pipe 2, a pair of split rings 27, 25, a pair of cylindrical nut 22, A configuration using the attracting means M according to 23 is also possible. In this structure, the fluid device 31 has a configuration in which an outward flange 31f is formed at the tip of the fluid supply / exhaust port portion 31b, and the first split ring that is externally fitted to the tubular portion 2A of the flange pipe 2 is provided. A second split ring 27 having an inner diameter larger than 25 is externally fitted to the fluid supply / discharge port portion 31b. In this case, for the convenience of assembling the second split ring 27, the outer flange 31f passes between the distal end of the cylindrical nut 22 that fits the fluid supply / discharge port 31b through the outward flange 31f and the outward flange 31f. It is necessary to set the length of the fluid supply / exhaust port portion 31b in the axis P direction so that there is a gap larger than the width of the second split ring 27 in the axis P direction.

  In addition to this, as the attracting means M, a fluid supply / exhaust port portion 31b such as a support frame device (not shown) that draws the fluid device 31 and the flange pipe 2 or the flange pipes 1 and 2 in a direction in which they are brought close to each other. The flange portion 2B or the flange portions 1B and 2B can be pressed and maintained.

  Although illustration is omitted, either one of the end surfaces of the flange portions 1B and 2B of the flange pipes 1 and 2 or the end surface of the fluid supply / discharge port portion 31b of the fluid device 31 and the end surface of the flange portion 2B of the flange pipe 2 An annular groove 6 and a first joint end 5 as shown in FIG. 2 and FIG. 10 are formed in one of these, and an annular projection 18 and a second joint end 17 as shown in FIG. 7 and FIG. It is also possible to adopt a connection structure using a gasket having a structure to be formed. Of course, in this case, the annular protrusion 8, the annular groove 16, and the first groove are formed on the one end surface and the other end surface of the gaskets G and G 2 to correspond to the shapes of the end surfaces of the fluid supply / discharge port portion 31 b and the flange portions 1 B and 2 B. Needless to say, the two joining end portions 15 and 7 are formed.

Overall schematic diagram showing the connection structure between flange pipes in Reference Example 1 FIG. 1 is a cross-sectional view of the main part showing the connection structure of FIG. (A)-(c) is explanatory drawing which shows the connection procedure of the connection structure of FIG. Half-cut cross-sectional view of the gasket used in the connection structure of FIG. Sectional drawing of the principal part which shows various different shapes of the fitting seal part of the connection structure of FIG. Half cutaway cross-sectional view of the main part showing the connection structure of flange pipes according to Reference Example 2 Half cutaway cross-sectional view of the main part showing the connection structure of flange pipes according to Example 1 Half-cut cross-sectional view of the gasket used in the connection structure of FIG. Schematic overall showing the connection structure between the flange pipe and a fluid device according to the Reference Example 4 FIG. 9 is a cross-sectional view of the main part showing the connection structure of FIG. 9 and the schematic connection structure according to Reference Example 3 . (A)-(c) is explanatory drawing which shows the connection procedure of the connection structure of FIG. Schematic overall showing the connection structure between the flange pipe and a fluid device according to the Reference Example 5 Schematic overall showing the connection structure between the flange pipe and fluid apparatus according to Example 2 Schematic overall showing the connection structure between the flange pipe and a fluid device according to the Reference Example 6 Schematic overall showing the connection structure between the flange pipe and a fluid device according to the Reference Example 7

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st flange piping 1h, 2h, 31h Hole 1A Tubular part 1B 1st flange part 1n Male thread part 2 2nd flange piping 2A Tubular part 2B 2nd flange part 3 Mating seal part 4, 9, 34 Fluid passage 5, 15 First joint end 15a Tapered inner peripheral surface 6, 16 Annular groove 6a Inner diameter portion 7, 17 Second joint end 17a Tapered outer peripheral surface 8, 18 Annular projections 21, 22, 23 Cylindrical nuts 21m, 22m, 23m Inside Peripheral surface portion 21n Female thread portion 22n Male thread portion 23n Female thread portion 24 Inward flange 24a Opening portion 25, 27 Split ring 31 Fluid device 31b Fluid supply / discharge port portion 31f Outward flange 31n Male thread portion 41 Bolt 42 Nut t1 First 1 seal end t2 2nd seal end G gasket M pulling means P shaft center

Claims (12)

The first flange portion of the first flange pipe having a first flange portion having a diameter larger than that of the tubular portion and made of a synthetic resin at the end of the tubular portion having the tubular fluid passage, and the tubular fluid passage. The second flange portion of the second flange pipe having a second flange portion having a diameter larger than that of the tubular portion and made of synthetic resin at an end portion of the tubular portion, and the first flange portion and the second flange portion, It is a connection structure of flange pipes that communicate with each other via a ring-shaped gasket interposed between them.
The fluid passage is opened so that the first flange portion and the second flange portion communicate with each other in a face-to-face relationship with each other, a first seal end portion is provided in the first flange portion, and the second flange portion is provided. Each flange has a second seal end,
The first seal end portion and the second seal end portion are formed by an annular groove or an annular protrusion formed in an outer diameter side portion of the fluid passage that opens at each end face of the first flange portion and the second flange portion. Configured,
An annular protrusion or annular groove that fits into the annular groove or annular protrusion of the first seal end is formed on the outer diameter side portion of the fluid passage that opens to one end face facing the end face of the first flange portion of the gasket. An annular projection formed and fitted into the annular groove or annular projection of the second seal end portion on the outer diameter side portion of the fluid passage that opens at the other end surface facing the end surface of the second flange portion of the gasket Or an annular groove is formed,
A pulling means for pulling the first flange portion and the second flange portion through the gasket and maintaining the pulling state over the first flange portion and the second flange portion. Prepared,
The annular groove or annular protrusion of the first seal end and the annular protrusion or annular groove of the one end surface of the gasket by the drawing action by the drawing means, and the annular groove of the second seal end Or the annular protrusion and the annular pipe or the annular groove on the other end face of the gasket are fitted together to form a fitting seal part, and the connection structure between flange pipes ,
The first seal end or the second seal end is constituted by the annular protrusion,
An annular second joint end is formed between the annular projection and the fluid passage at the first seal end or the second seal end constituted by the annular projection, and this second joint end. A tapered outer peripheral surface that is tapered to the outer peripheral surface of the tip is formed,
One end surface or the other end surface of the gasket in which an annular groove that fits the annular protrusion of the first seal end portion or the second seal end portion is formed is formed between the annular groove and the fluid passage. 1 joint end portion is formed, and a taper inner peripheral surface that comes into contact with the taper outer peripheral surface is formed in a taper shape on the tip inner peripheral surface of the first joint end portion,
Flange piping configured such that the tapered inner peripheral surface and the tapered outer peripheral surface are pressed against each other by pulling the first flange portion and the second flange portion together through the gasket by the pulling means. Connection structure between each other. The pulling means has an outer diameter larger than that of the first flange portion and is external to the tubular portion of the first flange pipe so as to interfere with the first flange portion in the axial direction of the first and second flange pipes. A first split mold ring to be fitted;
An inward flange having an opening that allows passage of the first flange portion and interferes with the first split ring in the axial direction is formed at one end portion, and on the outer periphery of the other end portion. A first cylindrical nut formed with a male screw part;
A second split ring that has an outer diameter larger than that of the second flange portion and is fitted onto the tubular portion of the second flange pipe so as to interfere with the second flange portion in the axial direction;
An inward flange having an opening that allows passage of the second flange portion and interfering with the second split ring in the axial direction is formed at one end portion, and an inner periphery of the other end portion And a second cylindrical nut formed with a female screw portion that can be screwed to the male screw portion.
The first flange portion and the second flange portion are attracted to each other via the gasket by the tightening operation of the cylindrical nuts by screwing the male screw portion and the female screw portion. The connection structure between flange pipes according to claim 1, which is configured. The pulling means has a cylindrical nut provided with a female screw portion that can be screwed into a male screw portion formed on an outer peripheral portion of the first flange portion, and an outer diameter larger than that of the second flange portion. A split ring that is fitted on the tubular portion of the second flange pipe so as to interfere with the second flange portion in the axial direction of the first and second flange portions;
An inward flange having an opening that allows passage of the second flange portion and interferes with the split ring in the axial direction is formed at one end of the cylindrical nut,
The clamping operation to the male threaded portion of the tubular nut, flange according to claim 1, wherein the first flange portion and the second flange portion is configured to be attracted through the gasket to one another Connection structure between pipes. The connection structure of flange piping of Claim 2 or 3 provided with the structure of at least one of following (I) and (B). (A) An inner peripheral surface portion of the split ring inner fitting portion adjacent to the inward flange of the cylindrical nut is formed on a flat inner peripheral surface concentric with the tubular fluid passage, and the inner periphery thereof The inner diameter of the surface portion and the outer diameter of the split ring formed in a rectangular cross section are formed to have substantially the same diameter. (B) An outer diameter portion of the tubular portion fitted on the split ring is formed on a flat outer peripheral surface concentrically with the tubular fluid passage, and an outer diameter of the outer diameter portion and the split portion The inner diameter of the mold ring is formed to be substantially the same diameter. The attraction means is composed of bolts and nuts that are passed through holes formed in the flange portions in a state along the axial direction of the first and second flange pipes;
Connecting structure of the flange pipe each other according to claim 1, and the second flange portion and the first flange portion is configured to be attracted through the gasket to one another by tightening the nut on the bolt. The connection structure between flange pipes according to any one of claims 1 to 5 , wherein the first and second flange portions and the gasket are formed of a fluorine-based resin. The flange portion of the flange pipe having a synthetic resin flange portion having a diameter larger than that of the tubular portion at the end portion of the tubular portion having the tubular fluid passage, and the fluid supply having the synthetic resin tubular fluid passage. A flange pipe and a fluid device that connect the fluid supply / discharge port portion of the fluid device including the discharge port through a ring-shaped gasket that is interposed between the flange portion and the fluid supply / discharge port portion. The connection structure of
The fluid passage is opened so that the flange portion and the fluid supply / discharge port portion communicate with each other in a face-to-face relationship, the first seal end portion is provided in the flange portion, and the fluid supply / discharge port portion is provided. Each with a second seal end,
The first seal end and the second seal end are configured by an annular groove or an annular protrusion formed in an outer diameter side portion of the fluid passage that opens at each end face of the flange portion and the fluid supply / discharge port portion. Has been
An annular protrusion or annular groove that fits into the annular groove or annular protrusion of the first seal end is formed on the outer diameter side portion of the fluid passage that opens to one end face facing the end face of the first flange portion of the gasket. An annular shape that is formed and fitted into the annular groove or annular projection of the second seal end portion on the outer diameter side portion of the fluid passage that opens to the other end surface facing the end surface of the fluid supply / discharge port portion of the gasket Forming protrusions or annular grooves,
A pulling means for pulling the flange portion and the fluid supply / discharge port portion through the gasket and maintaining the pulling state across the flange portion and the fluid supply / discharge port portion,
The annular groove or annular protrusion of the first seal end and the annular protrusion or annular groove of the one end surface of the gasket by the drawing action by the drawing means, and the annular groove of the second seal end Alternatively, the annular protrusion and the annular protrusion or the annular groove on the other end face of the gasket are fitted together to form a fitting seal portion, and the flange pipe and the fluid device are connected .
The first seal end or the second seal end is constituted by the annular protrusion,
An annular second joint end is formed between the annular projection and the fluid passage at the first seal end or the second seal end constituted by the annular projection, and this second joint end. A tapered outer peripheral surface that is tapered to the outer peripheral surface of the tip is formed,
One end surface or the other end surface of the gasket in which an annular groove that fits the annular protrusion of the first seal end portion or the second seal end portion is formed is formed between the annular groove and the fluid passage. 1 joint end portion is formed, and a taper inner peripheral surface that comes into contact with the taper outer peripheral surface is formed in a taper shape on the tip inner peripheral surface of the first joint end portion,
Flange piping configured so that the tapered inner peripheral surface and the tapered outer peripheral surface are brought into pressure contact with each other by pulling the flange portion and the fluid supply / discharge port portion through the gasket by the pulling means. And fluid equipment connection structure. The pulling means has a cylindrical nut provided with a female screw part that can be screwed into a male screw part formed on an outer peripheral part of the fluid supply / discharge port part, and has an outer diameter larger than that of the flange part. A split ring that is externally fitted to the tubular portion of the flange pipe so as to interfere with the flange portion in the axial direction of the flange portion and the fluid supply / exhaust port portion;
An inward flange having an opening that allows passage of the flange portion and interferes with the split ring in the axial direction is formed at one end of the cylindrical nut,
The flange pipe according to claim 7 , wherein the flange portion and the fluid supply / discharge port portion are drawn together via the gasket by a tightening operation of the cylindrical nut to the male screw portion. And fluid equipment connection structure. The attracting means has an outer diameter larger than that of the flange portion and is fitted on the tubular portion of the flange pipe so as to interfere with the flange portion in the axial direction of the flange portion and the fluid supply / discharge port portion. The first split ring,
An inward flange having an opening that interferes with the first split mold ring in the axial direction is formed at one end, and a male screw is provided on the outer periphery of the other end. A first cylindrical nut formed with a portion;
A second outer fitting that has an outer diameter larger than an outward flange formed at an end of the fluid supply / discharge port portion and is externally fitted to the fluid supply / discharge port portion so as to interfere with the outward flange in the axial direction. Split ring,
An inward flange having an opening that allows passage of the outward flange and that interferes with the second split ring in the axial direction is formed at one end, and at the inner periphery of the other end. A second cylindrical nut formed with a female screw portion that can be screwed into the male screw portion;
The flange portion and the fluid supply / exhaust port portion are attracted to each other via the gasket by the tightening operation of the cylindrical nuts by screwing the male screw portion and the female screw portion. The connection structure of the flange piping of Claim 7 comprised and the fluid apparatus. The connection structure between the flange pipe and the fluid device according to claim 8 or 9 , comprising at least one of the following configurations (a) and (b). (A) An inner peripheral surface portion of the split ring inner fitting portion adjacent to the inward flange of the cylindrical nut is formed on a flat inner peripheral surface concentric with the tubular fluid passage, and the inner periphery thereof The inner diameter of the surface portion and the outer diameter of the split ring formed in a rectangular cross section are formed to have substantially the same diameter. (B) The outer diameter portion of the tubular portion or the fluid supply / exhaust port portion to be externally fitted to the split ring is formed on a flat outer peripheral surface concentrically with the tubular fluid passage, and the outer diameter portion The outer diameter and the inner diameter of the split ring are formed to have substantially the same diameter. The pulling means is an outward flange formed on the outer periphery of the fluid supply / discharge port portion, and the flange portion and the outward flange in a state along the axial direction of the flange portion and the fluid supply / discharge port portion. It consists of bolts and nuts that pass through holes formed in each of the
The connection between the flange pipe and the fluid device according to claim 7, wherein the flange portion and the fluid supply / discharge port portion are attracted to each other via the gasket by tightening the nut to the bolt. Construction. The connection structure between the flange pipe and the fluid device according to any one of claims 7 to 11 , wherein the fluid supply / discharge port portion, the flange portion, and the gasket are formed of a fluorine-based resin.

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