JPH0750628Y2 - Pipe fitting - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint, and is particularly suitable for use in a pipe system for supplying ultrapure water, sterile water, etc. used in the fields of electronic industry, pharmaceutical manufacturing, food manufacturing, etc. Related to piping joints.

[0002]

2. Description of the Related Art In piping systems for supplying ultrapure water, aseptic water, etc. used in the fields of electronic industry, pharmaceutical manufacturing, food manufacturing, etc., in order to maintain high water quality, piping for forming flow paths While improving the cleanliness and stability of the inner surface,
It is necessary to strictly avoid the formation of a liquid pool that causes bacteria to propagate in the flow path and the intrusion of dust from the piping components such as the joint into the flow path. Therefore, the pipe joint in the pipe system also has its own restrictions, and the pipe joint having the structure shown in FIG.

In this conventional pipe joint, simple flanges (11a) and (12a) are integrally formed at the pipe ends of the pipes (11) and (12) to be connected, and the inner surface and In addition to facilitating cleaning and stabilization of the connecting surface, the flanges (11a), (12a) of these pipes (11), (12) are made to face each other, and a lap joint mounted on the outer peripheral side of By connecting with a holding member (14) such as a ferrule clamp, dust generation from the joint part is suppressed to a low level, while at the same time, the flange (11a), (12a) has an annular mounting between the sealing surfaces on the innermost diameter side. Liquid sealing with the O-ring (13) prevents the formation of a liquid pool at the joint part, and even when dust is generated from the crimping surfaces of both flanges (11a), (12a), The O-ring (13) prevents dust from entering the flow path. In addition, a sealing recess (11b) having a rectangular cross section is provided around the innermost sealing surface of the flange (11a) of one pipe (11), and the other pipe (1
The seal surface on the innermost diameter side of the flange in 2) is provided with a seal protrusion (12b) that fits into the former seal recess (11b). To ensure proper alignment of (11a) and (12a), the innermost diameter side of both flanges (11a) and (12a) for mounting and filling the O-ring (13). An annular space with a rectangular cross section is formed.

[0004]

However, in the above-mentioned conventional pipe joint, the pipes to be connected can have a relatively simple shape, and the inner surface and the connecting surface can be easily cleaned and stabilized. In addition, by mounting an O-ring on the innermost diameter side of both flanges to be joined, a liquid pool that causes bacterial growth can be formed at the joint part and dust from the crimping surface of the flange. Although it can be prevented from invading into the flow path, there are problems in terms of its pipe workability and maintenance of the liquid seal in case of pressure fluctuation inside the pipe.

That is, since the flange end faces of the pipe ends of one and the other of the pipes to be connected are in a mating relationship of male and female, the directionality of the combination occurs in these pipes, and the pipe construction is complicated. It should be Further, since the O-rings for liquid sealing are formed on the innermost diameter side of both flanges and are mounted in the annular space having a rectangular cross section that opens to the inner diameter side, the pressure inside the pipe is on the negative side. In this case, this O-ring is likely to fall inward and impair the liquid sealing function, which causes a serious trouble.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and the flanges formed at the pipe ends of the pipes to be connected have the same shape to facilitate the piping work. , The O-rings can be attached to the innermost diameter sides of the flanges of both pipes to be connected, and the formation of a liquid pool at the joint can be prevented, and the pressure inside the pipe becomes negative. Even in such a case, it is an object of the present invention to provide a pipe joint capable of reliably holding the O-ring that is annularly mounted on the innermost diameter side without dropping inward and stably maintaining the liquid sealing function. .

[0007]

In order to achieve the above object, the present invention has the following configuration. That is, in the pipe joint according to the present invention, a flange is formed at the pipe end, and the seal end face of the flange has a rectangular axial cross-sectional shape, and the innermost diameter side is smaller than the depth of the main body portion. A tubular body formed by surrounding a sealing recess formed in an annular small projection protruding in the axial direction with the flanges of the respective pipe ends facing each other, while the annular recess formed by the sealing recesses of the facing flanges. A fitting ring having a rectangular cross-section made of a hard material was fitted on the outer peripheral side of the space, an O ring was mounted inside the fitting ring, and the flanges of these pipes were mounted on the outer peripheral side. It is characterized by being joined by a holding member.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a sectional view showing the structure of a pipe joint according to an embodiment of the present invention.

In FIG. 1, (1) and (1 ') are tubes made of stainless steel (JIS; SUS316L).
(1) and (1 ') are flanges (1a) and
(1a ') is integrally formed. Also,
The seal end surface of each flange (1a), (1a ') has a rectangular axial cross-sectional shape, and an annular small protrusion whose innermost diameter side projects in the axial direction with a dimension smaller than the depth of the main body.
(1c), seal recesses of the same shape formed in (1c ') (1b), (1b')
Are installed around. The tubular bodies (1) and (1 ′) are passivated by electrolytically polishing the inner diameter surface and the seal end surface of the flange and then heating them at a high temperature.

The pipe bodies (1), (1 ') are arranged such that the flanges (1a), (1a') at the pipe ends face each other, and the flanges (1a), (1a ') face each other. ), The fitting ring (2) made of stainless steel (JIS; SUS316L) with a square cross section is fitted on the outer peripheral side of the annular space formed by the seal recesses (1b), (1b '). A ferrule in which an O-ring (3) made of Teflon is annularly mounted in the annular space inside (2) and then both flanges (1a) and (1a ') are attached to the outer peripheral side thereof. It is connected and connected by the clamp (4).

Here, the fitting ring (2) has a seal recess of the flanges (1a), (1a ') whose outer diameter is substantially equal to that of the seal recess (1b) and whose widthwise dimensions are opposed to each other. (1b), (1b ') is a ring having a square cross-sectional shape slightly smaller than the axial dimension of the annular space formed, the seal recesses (1b), (1b) of the opposing flanges (1a), (1a') It is supposed to be fitted to the outer peripheral surface of ') with a predetermined fitting accuracy. This mating ring (2)
By being fitted to the outer peripheral side of each of the seal recesses (1b), (1b '), both flanges (1a), (1a') of the tubular bodies (1), (1 ') are assembled. Make centering easy and reliable. The outer surface of the fitting ring (2) is subjected to the same passivation treatment as that of the pipe bodies (1) and (1 ′).

On the other hand, when the O-ring (3) is joined and connected by the ferrule clamp (4), the opposing flange (1
a), (1a ') seal recesses (1b), (1b') are formed inside the fitting ring (2) in the annular space, which is deformed and filled, and the inner end face of the tubular body (1), (1) 1 ') has a diameter and a cross-sectional area that are equal to or slightly projecting from the inner diameter surface of 1'), and prevent the formation of a liquid pool in the joint portion and fulfill the liquid seal of the joint portion.

The small annular projections (1c), (1c ') formed on the innermost diameter side of the seal recesses (1b), (1b') smoothly deform the O-ring (3) without damaging it. The axial cross-sectional shape is made to project in a triangular shape that gradually inclines while reducing the diameter toward the innermost diameter surface.

In the pipe joint of this embodiment having the above-mentioned structure, no liquid pool is formed in the joint portion,
Moreover, since the flanges formed at the pipe ends of the pipes to be connected have the same shape, there is no directionality of the combination, and the pipe construction is significantly facilitated. Further, since the O-ring is mounted on the innermost diameter side of the joint portion, even if dust is generated from the crimping surfaces of the flanges facing each other and the contact surface of the flange and the fitting ring, the O-rings generate the dust. It is possible to reliably prevent dust from entering the flow path. In addition, since a small annular projection protruding in the axial direction is formed on the innermost diameter side of the seal recess where the O-ring is mounted and filled, even if the pressure inside the pipe is negative, this annular projection is formed. The small protrusion can securely hold the O-ring without dropping it inward.

In this embodiment, the tubular body and the fitting ring are made of stainless steel (SUS316L) and the predetermined surface is passivated, but this is an example. As long as it is stable to sterilized water or the like and has no eluate or the like, it may be made of another constituent material such as a glass lining material or a synthetic resin material. Also, O
Similarly, the ring is not limited to the one made of Teflon, but may be made of another material such as Viton.

[0016]

As described above, according to the pipe joint of the present invention, the flanges formed at the pipe ends of the pipes to be connected have the same shape to facilitate the pipe construction. An O-ring can be attached to the innermost diameter side of both flanges of the pipes to be connected to prevent formation of a liquid pool at the joint, and the quality of water such as ultrapure water or sterile water flowing inside the pipes. Can be maintained at a high level, and even if the pressure inside the pipe is on the negative side, the O
The ring can be securely held without falling inward, and its liquid sealing function can be stably maintained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a piping joint according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a configuration of a conventional piping joint.

[Explanation of symbols]

 (1), (1 ')-Tube (1a), (1a')-Flange (1b), (1b ')-Seal recess (1c), (1c')-Small annular projection (2 ) --Mating ring (3) --O ring (4) --Ferrule clamp

Front page continuation (72) Nobuyuki Hirose 286-1 Noguchi-cho, Kakogawa-shi, Hyogo Prefecture A-413 (72) Teizo Mizutani 6-13-2, Fujita-cho, Moriguchi-shi, Osaka (56) References 60-184795 (JP, A) Actual Kaihei 3-98362 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A flange is formed at a pipe end, and a sealing end surface of the flange has a rectangular axial cross-sectional shape, and an innermost diameter side thereof projects in the axial direction with a dimension smaller than a depth of a main body portion. The pipes, which are formed by surrounding the sealing recesses formed in the annular small projections, are arranged so that the flanges of the respective pipe ends face each other, while the rigid body is formed on the outer peripheral side of the annular space formed by the sealing recesses of the facing flanges. A fitting ring with a rectangular cross-section made of material is fitted and the O inside the fitting ring
A pipe joint, characterized in that a ring is mounted, and the flanges of these pipes are joined by a holding member mounted on the outer peripheral side thereof.