JPH07217785A - Sealing device at branch connection of gas conduit - Google Patents

Abstract

(57) [Summary] [Purpose] To properly branch and connect gas conduits. [Structure] A composite sheet 20 and a rubber sheet 25 having an insulating property and an elastic force are attached to the outer surface of the branch portion of the gas conduit 1, and further an O-ring 15 is attached to the periphery of the branch port 2, and then the branch portion The branched cheese 4 is fixed by the split sleeve 10. Since no welding means is used at the branch connection of the gas conduit 1, a welder skilled in welding work is not required, and the mist that the anticorrosive paint applied to the inside of the gas conduit 1 is gasified and floats does not occur. Therefore, there is no problem that the floating mist flows to the gas appliance of the customer and causes ignition failure. The soft butyl rubber layer 21 of the composite sheet 20 elastically deforms in response to the buckling deformation of the gas pipe 1 serving as the main pipe due to the behavior of the ground due to an earthquake or the bending load caused by an external factor such as a wheel load of a heavy vehicle. By entering the intervening gap of the O-ring formed on the inner peripheral surface of the sleeve body 11, the gas is reliably sealed and the problem of gas leakage does not occur.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a branch connection part of a gas pipe in which a branch pipe for drawing gas to a demand destination is branched from a gas pipe buried under a road. The present invention relates to a sealing device in a branch connection portion of a gas conduit that seals against leakage.

[0002]

2. Description of the Related Art A gas pipe is branched from a gas pipe buried under a road so that a branch pipe for drawing gas to a demand destination is branched. Conventionally, for example, as shown in FIG. 4, this branch connection portion is formed by welding and bonding a wrought iron socket 3 to a pipe body at a branch port 2 of a gas conduit 1, and connecting the branch pipe 5 to the wrought iron socket 3.
The connection port 6 of the branch fitting 4 to which is connected is connected by screwing a screw.

[0003]

By the way, in the case of the structure in which the wrought iron socket 3 is weld-bonded to the tube body of the gas conduit 1 as described above, an operator (welder) having a skill in welding work is required. In addition to this, there were the following problems.

That is, the gas conduit 1 is heated by heating during welding.
The paint for rust prevention applied to the inner surface of the pipe is gasified and peels off, which causes a floating phenomenon, so that the floating mist flows from the branch connection part through the branch pipe 5 to the gas appliance at the demand destination. However, there is a problem in that the proportional control valve of the gas appliance, the nozzle, and the like are clogged to cause ignition failure.

In order to eliminate the problems caused by such welding, the branch connection portion is provided with a split sleeve which is divided into upper and lower halves, and a socket (insertion port) for connecting the connection port of the branch fitting to the sleeve body. Prior art of a structure in which a branch metal fitting is connected to this is also proposed.

However, when the branch sleeve is laid in the ground by using the split sleeve, buckling deformation may occur at the branch connection due to external factors such as the behavior of the ground due to an earthquake or the wheel load of a heavy vehicle. There is a problem that gas leaks from the branch port due to this.

The present invention has been made in consideration of such a situation, and prevents gas from leaking from a branch connection portion even if the gas conduit undergoes buckling deformation, and also branches the gas conduit. It is an object of the present invention to provide a sealing device in a branch connection part of a gas conduit, which can be properly connected.

[0008]

As a means for achieving the above object, the present invention is a branch pipe branching method from a gas conduit buried in the ground to attach a split sleeve half-divided vertically to the gas conduit. The branch connecting portion of the gas pipe for branching the branch pipe by connecting the branch pipe branch fitting to the split sleeve branch port is configured as follows.

The upper and lower split sleeves are joined to the outer circumference of the pipe body through a sheet-like seal member, and one sleeve body is provided with a branch metal fitting corresponding to the branch port of the gas conduit. The sleeve includes an insertion port portion that airtightly connects the connection ports, and an O-ring that is arranged between the inner peripheral surface of the sleeve body and the seal member so as to surround the opening peripheral portion of the insertion port portion. The seal member interposed on the inner peripheral side of the main body has a three-layer structure in which a soft rubber layer softer than the rubber layer is compounded on the front and back of the intermediate rubber layer, and the gas conduit is laid with the upper and lower split sleeves fastened. Even when the tubular body of the gas conduit is deformed due to an external factor, the soft rubber layer of the seal member enters the intervening gap of the O-ring formed on the inner peripheral surface of the sleeve body to prevent the gas from the branch port. Characterized by being configured to block outflow Than it is.

[0010]

According to the above-mentioned structure, since welding means is not used at the branch connecting portion of the gas conduit, a welder skilled in welding work is not required, and the rust-preventive paint applied inside the pipe of the gas conduit is not required. Since the mist that gasifies and floats is not derived, the problem that the floating mist flows to the gas appliance of the customer and causes ignition failure does not occur.

Even when the main gas pipe is a steel pipe which causes buckling deformation, the soft rubber layer of the seal member is formed on the inner circumference of the sleeve body against buckling deformation caused by external factors during installation. By entering the intervening gap of the O-ring formed on the surface, the sealing of the gas is ensured and the problem of gas leakage does not occur.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings described below, the same parts as those in FIG. 4 are designated by the same reference numerals.

FIG. 1 and FIG. 2 show an embodiment of a sealing device at a branch connecting portion of a gas conduit according to the present invention. As shown in these drawings, a branch cheese 4 that connects the supply pipe 5 via a split sleeve 10 is attached to a position surrounding the branch port 2 of the gas conduit 1.

The split sleeve 10 is divided into a sleeve body 11 and a sleeve body 17. The sleeve main body 11 is provided with a holding cylinder portion 12 for closely holding the connection port 6 of the branched cheese 4 and a flange portion 13 protruding horizontally on both sides with respect to the axial direction of the gas conduit 1. Further, a male screw portion is formed on the outer peripheral surface of the connection port 6 of the branched cheese 4, and the holding cylinder portion 1 of the sleeve body 11 is further formed.
A female screw portion is formed on the inner peripheral surface of 2, and the branched cheese 4 is connected to the sleeve body 11 by screwing the male screw portion and the female screw portion. Split sleeve 1
On the inner wall surface of 0, a positioning groove 14 having a size surrounding the periphery of the branch port 2 of the gas conduit 1 is formed. Positioning groove 1
An O-ring 15 is fitted to 4.

The sleeve body 17 is provided with a flange portion 16 projecting in the same direction as the sleeve body 11.
The sleeve body 11 and the sleeve body 17 are fastened together by bolts 18 and nuts 19 mounted between the flange portions 13 and 16.

A composite sheet 20 having a three-layer structure is interposed between the outer peripheral surface of the gas conduit 1 and the inner peripheral surface of the sleeve body 11. Outer peripheral surface of gas conduit 1 and sleeve body 17
A rubber sheet 25 is interposed between the inner peripheral surface and the inner peripheral surface.

FIG. 3 shows the details of the composite sheet 20, for example, the soft butyl rubber layers 21 and 2 having a thickness of 3 mm.
3, the NBR rubber layer 22 having a thickness of 3 mm is sandwiched between the two. Although not shown, the composite sheet 20 is formed with an opening so as not to block the branch port 2 of the gas conduit 1 when it is mounted on the outer surface of the gas conduit 1.

Next, a method of mounting the gas conduit branching device having such a configuration will be described. First, the composite sheet 20 is attached to the outer surface of the gas conduit 1. At this time, the opening of the composite sheet 20 is aligned with the branch port 2 of the gas conduit 1 so that the composite sheet 20 does not block the branch port 2 of the gas conduit 1.

After the mounting of the composite sheet 20, the sleeve body 11 of the split sleeve 10 is mounted on the outer surface of the gas conduit 1 from above the composite sheet 20. At this time, the holding cylinder portion 12 of the sleeve body 11 and the branch port 2 of the gas conduit 1 are aligned with each other.

After mounting the sleeve body 11, the rubber sheet 25 and the sleeve body 17 are mounted on the lower half side of the gas conduit 1. After the mounting of the sleeve body 17 is completed, the flanges 13 and 16 are fastened with bolts 18 and nuts 19.

After the split sleeve 10 has been attached to the gas conduit 1, the connection port 6 of the branched cheese 4 is connected to the holding cylinder portion 12 of the sleeve body 11 by screwing the screw portion. Branched cheese 4
In that case, the supply pipe 5 is connected in advance.

As a result, the split sleeve 10 and the gas conduit 1 are
Since the O-ring 15 is interposed between the branch opening 2 and the branch opening 2, the gas leakage from the branch opening 2 is prevented. Further, the branched cheese 4 and the gas conduit 1 are electrically insulated by the rubber layer 22 and the rubber sheet 25 of the composite sheet 20. Furthermore, although the opening edge of the branching port 2 of the gas conduit 1 is slightly weaker in strength, stress is applied to the opening edge of the branching port 2 due to external factors such as the behavior of the ground due to an earthquake or the wheel load of a heavy vehicle. Even when the buckling deformation is caused by the addition of the elastic member, the soft butyl rubber layer 21 of the composite sheet 20 elastically deforms and enters the positioning groove 14 into which the O-ring 15 is fitted, and the split sleeve 1
The O-ring 15 between 0 and the branch port 2 maintains the airtightness.

As described above, in this embodiment, the composite sheet 20 and the rubber sheet 25 having the insulating property and the elastic force are attached to the outer surface of the branch portion of the gas conduit 1, and the O-ring is further provided around the branch opening 2. After mounting 15, the branched cheese 4 was fixed by the split sleeve 10 at the branch point.

Therefore, since no welding means is used at the branch connecting portion of the gas conduit 1, a welder skilled in welding work is not required, and the rust preventive paint applied to the inside of the gas conduit 1 is gasified and floats. There is no problem that the floating mist flows to the gas appliance of the demand destination and the ignition failure occurs because no mist is generated.

The soft butyl rubber layer 21 of the composite sheet 20 is elastic against the buckling deformation of the gas pipe 1 which is the main pipe due to the bending behavior due to the external factors such as the behavior of the ground due to the earthquake or the wheel load due to the heavy vehicle. By deforming and entering the intervening gap of the O-ring formed on the inner peripheral surface of the sleeve body 11, the sealing of the gas is ensured and the problem of gas leakage does not occur.

[0026]

As described above, according to the sealing device for the branch connecting portion of the gas conduit of the present invention, since welding means is not used for the branch connecting portion of the gas conduit, a welder skilled in welding work is required. It is not necessary, and since the mist that the anticorrosive paint applied to the inside of the gas conduit is gasified and floating does not occur, the problem that the floating mist flows to the gas appliance of the customer and causes ignition failure does not occur.

In addition, the soft rubber layer of the seal member is formed by the soft rubber layer of the seal member on the inner circumference of the sleeve body in response to buckling deformation of the gas pipe serving as the main pipe due to bending load due to external factors such as ground behavior due to earthquake or wheel load due to heavy vehicle. By entering the intervening gap of the O-ring formed on the surface, the sealing of the gas is ensured and the problem of gas leakage does not occur. Therefore, even if the gas conduit is a steel pipe and the pipe body is subjected to buckling deformation, it is possible to appropriately perform the branch connection of the gas conduit, such as preventing leakage of gas from the branch connection portion.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a sealing device in a branch connection portion of a gas conduit of the present invention.

FIG. 2 is a cross-sectional view showing a sealing device at a branch connection portion of the gas conduit shown in FIG.

FIG. 3 is a diagram showing details of the composite sheet of FIG.

FIG. 4 is a cross-sectional view showing a branched cheese structure for connecting a conventional gas conduit and a supply pipe.

[Explanation of symbols]

 1 Gas Conduit 2 Branch Port 4 Branch Cheese 5 Supply Pipe 10 Split Sleeve 11 Sleeve Main Body 12 Holding Cylinder 13, 16 Flange 15 O Ring 17 Sleeve Body 20 Composite Sheet 21,23 Butyl Rubber Layer 22 Rubber Layer 25 Rubber Sheet

Claims (1)

[Claims] 1. A branch pipe in which a split sleeve, which is divided into upper and lower halves, is attached to the gas conduit by a branch pipe branching method from a gas pipe buried in the ground, and a branch pipe branch metal fitting is connected to the split sleeve branch opening. In the branch connection part of the gas conduit for branching work, the split sleeve, which is divided into upper and lower parts, is joined to the outer circumference of the pipe body via a sheet-shaped sealing member, and one of the sleeve bodies has a gas conduit Is arranged between the inner peripheral surface of the sleeve body and the seal member so as to surround the insertion port portion that airtightly connects the connection port of the branch fitting corresponding to the branch port of And a seal member interposed on the inner peripheral side of the sleeve body,
A three-layer structure in which a soft rubber layer that is softer than the rubber layer is compounded on the front and back of the intermediate rubber layer, and the pipe body of the gas conduit is deformed by external factors while the gas conduit is laid with the upper and lower split sleeves fastened. Also in this case, the soft rubber layer of the seal member enters the intervening gap of the O-ring formed on the inner peripheral surface of the sleeve body to block the outflow of gas from the branch port. Sealing device at branch connection of conduit.