JP4275953B2 - Flange joint for fluid piping connection - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flange joint for fluid pipe connection (hereinafter simply referred to as a flange joint) that ensures insulation between a fluid pipe and a connection object.
[0002]
[Prior art]
In many cases, a metal pipe connected to a device that uses a conductive body as a part of electrical wiring is required to be insulated from the device so as not to get an electric shock even if the tube is touched.
A simple means for providing insulation between equipment and piping is to interpose a rubber tube joint in the middle of the piping and cut off the current at the joint. If the tube is exposed, it is likely to be adversely affected by acid, alkali, heat, etc., and gas such as hydrogen permeates through the rubber structure and leaks.
Even if a metal pipe is inserted into a rubber tube and fastened or banded with a band, there is a problem of airtightness and reliability is poor.
On the other hand, the thing which gave the insulation to the flange joint by interposing an insulator between a flange and a volt | bolt is proposed by the content shown by patent document 1 or patent document 2, for example.
[0003]
[Patent Document 1]
JP-A-6-101789 [Patent Document 2]
JP 2000-329293 A.
[0004]
[Problems to be solved by the invention]
In the conventional flange joint, since the metal conductive surface is continuous in the fluid passage from the flange to the metal pipe, in the fluid passage, the equipment to be connected and the metal pipe that is the piping are flanges. Even though it is physically separated by the thickness of the insulation interposed between them, there is a high possibility of causing a discharge phenomenon, and water vapor charged in the fluid passage will pass through. In this case, the insulation against the water vapor cannot be secured.
In addition, if the bolt is a stud type that is screwed into the connection destination, voltage is applied to the bolt head (nut), which may cause a discharge phenomenon between the bolt head and the metal pipe. is there.
[0005]
[Means for Solving the Problems]
The present invention is a flange joint for fluid pipe connection with high insulation, and the structure thereof is provided around a first flange having a first bolt insertion hole provided around an end of a metal pipe, and a connection target An insulating gasket is sandwiched between a second bolt insertion hole corresponding to the first bolt insertion hole in the first flange or a second flange having a bolt screw hole. The insulating gasket protrudes coaxially with the third bolt insertion hole and the third bolt insertion hole at a portion corresponding to the first bolt insertion hole in the first flange. A cylindrical portion that can be inserted into the insertion hole is formed, and a fluid passage and a tube that can be inserted into the metal pipe are formed coaxially with the fluid passage at a portion corresponding to the metal pipe. 1st bolt insertion A fluid pipe connection flange joints are connected by a bolt via an insulating ring having a collar body at an end portion insertable cylindrical portion into the hole, it is interposed a bush between the bolt and the insulating ring It is characterized by that.
[0006]
Further, the present invention is the above-described flange joint for fluid pipe connection, in which a tubular end wall of the tube is formed by projecting the base end portion of the tube with the metal pipe in the first flange and the second flange. It is characterized by being sandwiched and supported by.
Furthermore, the present invention is the above-described flange joint for fluid pipe connection, wherein the insulating ring includes a ring wall that surrounds the head of the bolt to the tip at the periphery of the housing.
Then, the insulating gasket, or a flange cover for covering the outer periphery of the second flange on the periphery, also be or be interposed a gasket bead therebetween with the insulating gasket and the first and second flanges Can do.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a flange joint for fluid pipe connection according to the present invention will be described with reference to the drawings.
In FIG. 1, reference numeral 1 denotes a metal pipe which is an object to be connected. A first flange 2 having first bolt insertion holes 2 a and 2 a is provided around the end of the metal pipe 1. Yes.
3 is a 2nd flange provided in the connection object, and is the same shape as the said 1st flange 2, and the bolt insertion hole 2a. Bolt screw holes 3a and 3a are formed in the portion corresponding to 2a, and a cylindrical wall 3b is projected from the portion corresponding to the metal pipe 1.
4 is an insulating gasket made of rubber. The insulating gasket 4 has third bolt insertion holes 4a. 4a at portions corresponding to the first bolt insertion holes 2a and 2a in the first flange 2. 4a and the cylindrical portions 5 and 5 that can be inserted into the first bolt insertion holes 2a in the first flange 2 are provided in the third bolt insertion holes 4a. 4a is formed so as to be coaxial with the pipe 4a, and a fluid passage 6 and a tube 7 that can be inserted into the metal pipe 1 are formed coaxially with the fluid passage 6 so as to correspond to the metal pipe 1. Has been.
The insulating gasket 4 is provided with a flange cover 8 covering the outer periphery of the second flange 3 on the periphery.
The first and second flanges 2 and 3 and the insulating gasket 4 are substantially diamond-shaped and are bolted at two locations. These are triangular or circular, or the number of bolting locations is changed. The design is free.
[0008]
These first flange 2, second flange 3, and insulating gasket 4 sandwich the insulating gasket 4 between the first flange 2 and the second flange 3, and connect the insulating ring 9 and the bush 10. Then, the bolt 11 is fastened and fixed.
The insulating ring 9 is made of epoxy resin, and has a casing 9b at the upper end of the cylindrical portion 9a that can be inserted into the bolt insertion hole 2a. And a ring wall 9c surrounding the tip of the bolt including the bolt.
The bush 10 includes a housing 10b at the upper end edge of the inner cylinder 10a that can be inserted into the cylinder portion 9a of the insulating ring 9, and is made of a highly rigid metal.
[0009]
In order to fasten and fix the flange joint formed in this way with a bolt, for example, the bolt 11 is screwed into the bolt screw hole 3a in the second flange 3 and fixed like a stud bolt. The protruding tube 7 is inserted into the metal pipe 1, and the cylindrical portion 5 is inserted into the first bolt insertion hole 2 a in the first flange 2, so that the insulating gasket 4 is in close contact with the first flange 2. .
Subsequently, the cylindrical wall 3b protruding from the first flange 2 is pushed into the tube 7 of the insulating gasket 4, and the insulating ring is inserted into the cylindrical portion 5 inserted into the first bolt insertion hole 2a. 9 is inserted, and then the inner cylinder 10a of the bush 10 is inserted into the cylinder 9a of the insulating ring 9, and the bolt fixed to the second flange 3 in the inner cylinder 10a. 11 is inserted and tightened with a nut 11b through a washer 11a.
The insulating ring 9 and the bush 10 are positioned by the casings 9b and 10b, respectively, and the rubber insulating gasket 4 is fixed in size with the lower end of the inner cylinder 10a of the bush 10 being in pressure contact with the second flange 3. It is tightened.
[0010]
In the flange joint assembled as shown in FIG. 2, since the tube 7 formed in the insulating gasket 4 is inserted into the metal pipe 1, the insulating gasket 4 extends to the creeping portion of the tube 7 with respect to the metal pipe. Insulation is continued, and the insulation in the fluid passage is kept high. Even if a fluid such as charged water vapor passes through, it does not affect the outside.
Further, the tube 7 is supported by being sandwiched and supported by the base end portion between the joint portion of the first flange 2 with the metal pipe 1 and the cylindrical wall 3 b protruding from the second flange 3. Even if there is a load, it is not pulled inward.
Further, the periphery of the bolt head (nut) 11b is surrounded by the ring wall 9c up to the head of the bolt, the space between the metal pipe 1 and the metal pipe 1 is shielded by the ring wall 9c, and the peripheral surface of the second flange 3 is Since it is covered with the flange cover 8, electric discharge is also prevented.
Reference numeral 12 shown in the drawing is an O-ring for securing a sealing property between the second flange 3 and the object to be connected, and 13 and 13 are insulations in the flanges 2 and 3, respectively. The insulating gasket 4 and the first and second surfaces of the insulating gasket 4 are protruded from the front and back surfaces of the insulating gasket 4 so as to correspond to the concave grooves 3c and 3c formed around the fluid passage 6. This is a gasket bead that maintains a sealing property between the first and second flanges 2 and 3.
[0011]
In the embodiment, the second flange employs a bolt screw hole instead of the second bolt hole. However, in the present invention, the bolt insert hole and the bolt screw hole have the same meaning. The same applies to the relationship between the bolt head and the nut.
The second flange assumes that the object to be connected is like a container. However, when the object to be connected is a metal pipe, the first flange and the second flange are used. It is assumed that the tube is not distinguished from the second flange, and the tube is inserted into the metal pipe in the same manner as the first flange with respect to the second flange, and can be shaped symmetrically.
[0012]
【The invention's effect】
According to the present invention, it is possible to maintain high insulation in the fluid passage by ensuring the creepage distance of the tube. In particular, even when charged water vapor or the like passes through the fluid passage, insulation against the water vapor is ensured. Is done.
In addition, if measures are taken to prevent the discharge phenomenon with a flange cover or an insulating ring, the reliability will be further improved, and gasket bead processing will be applied between the insulating gasket and the flange, resulting in perfect sealing performance. It will be something.
Further, even if there is an internal pressure load, the proximal end portion of the tube is sandwiched and supported by the joint portion between the first flange 2 and the metal pipe and the cylindrical wall projecting from the second flange. It is prevented from being pulled inward.
[Brief description of the drawings]
FIG. 1 is an exploded explanatory view showing a flange joint according to the present invention with a part cut away.
FIG. 2 is an assembly explanatory view showing a flange joint partly cut away.
[Explanation of symbols]
1 ... Metal pipe, 2 ... First flange, 2a ... First bolt insertion hole, 3 ... Second flange, 3a ... Bolt screw hole, 3b ... Cylindrical wall, 3c ... Recessed groove, 4 ... Insulating gasket, 4a ... 3rd bolt insertion hole, 5 ... Tubular part, 6 ... Fluid passage, 7 ... Tube, 8 ... Flange cover, 9 ... Insulating ring, 9a..Cylinder, 9b..Case, 9c..Ring wall, 10..Bushing, 10a..Inner cylinder, 10b..Case, 11..Bolt, 11a..Washer, 11b..Nut 12, O-ring, 13 gasket gasket bead.

Claims (5)

A first flange that is provided around the end of the metal pipe and includes a first bolt insertion hole, and a second flange that is provided in the connection target and corresponds to the first bolt insertion hole in the first flange. An insulating gasket is sandwiched between a bolt insertion hole or a second flange having a bolt screw-in hole, and the insulating gasket has a portion corresponding to the first bolt insertion hole in the first flange. In addition, a third bolt insertion hole and a cylindrical portion protruding coaxially with the third bolt insertion hole and insertable into the first bolt insertion hole are formed, and corresponds to a metal pipe. A tube that can be inserted into the fluid passage and the metal pipe protrudes coaxially with the fluid passage, and has a casing at the end of the cylindrical portion that can be inserted into the first bolt insertion hole. Bolted through the insulated ring That a flange joint for fluid pipe connection,
A flange joint for connecting a fluid pipe, wherein a bush is interposed between the bolt and the insulating ring. A first flange that is provided around the end of the metal pipe and includes a first bolt insertion hole, and a second flange that is provided in the connection target and corresponds to the first bolt insertion hole in the first flange. An insulating gasket is sandwiched between a bolt insertion hole or a second flange having a bolt screw-in hole, and the insulating gasket has a portion corresponding to the first bolt insertion hole in the first flange. In addition, a third bolt insertion hole and a cylindrical portion protruding coaxially with the third bolt insertion hole and insertable into the first bolt insertion hole are formed, and corresponds to a metal pipe. A tube that can be inserted into the fluid passage and the metal pipe protrudes coaxially with the fluid passage, and has a casing at the end of the cylindrical portion that can be inserted into the first bolt insertion hole. Bolted through the insulated ring That a flange joint for fluid pipe connection,
A fluid pipe connection characterized in that the base end portion of the tube is sandwiched and supported by a seam portion of the first flange with the metal pipe and a cylindrical wall projecting from the second flange. For flange joints. A first flange that is provided around the end of the metal pipe and includes a first bolt insertion hole, and a second flange that is provided in the connection target and corresponds to the first bolt insertion hole in the first flange. An insulating gasket is sandwiched between a bolt insertion hole or a second flange having a bolt screw-in hole, and the insulating gasket has a portion corresponding to the first bolt insertion hole in the first flange. In addition, a third bolt insertion hole and a cylindrical portion protruding coaxially with the third bolt insertion hole and insertable into the first bolt insertion hole are formed, and corresponds to a metal pipe. A tube that can be inserted into the fluid passage and the metal pipe protrudes coaxially with the fluid passage, and has a casing at the end of the cylindrical portion that can be inserted into the first bolt insertion hole. Bolted through the insulated ring That a flange joint for fluid pipe connection,
A flange joint for connecting a fluid pipe, wherein the insulating ring includes a ring wall that surrounds the head of the bolt to the tip at the periphery of the housing. The flange joint for fluid piping connection in any one of Claims 1-3 with which the insulating gasket was provided with the flange cover which covers the outer periphery of a 2nd flange in a periphery. The flange joint for fluid piping connection according to any one of claims 1 to 4 , wherein a gasket bead is interposed between the insulating gasket and the first and second flanges.

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