JPH0434314Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The invention is useful, for example, for branch pipes and merging pipes in internally treated pipes such as water and sewerage pipes and gas pipes that have been repaired by inserting new pipes into existing pipes. This invention relates to the structure of an opening for connecting branch pipes such as pipes.

More specifically, an opening for connecting a branch pipe is formed in the peripheral wall of the internally treated pipe, in which an inner pipe made of synthetic resin or the like is installed inside an existing pipe or the like, and the gap between the existing pipe and the inner pipe is filled with cement. Regarding the structure of

[Prior Art] This type of branch pipe connection opening has conventionally been [1] As shown in Figure 3 of the drawings, an opening for connecting an existing pipe 1'
After cutting out and removing a part of the cement 3' over its entire circumference, a cap 6 is fixed to the outer circumference of the inner pipe 2', and a hole is bored in the inner pipe 2' to form a branch path.

[2] As a branch joint, a joint with a cylindrical part that is fitted inside the branch saddle is used, a tapered part is formed at the lower end of the cylindrical part, and a packing is attached to the small diameter part of the taper. In this state, insert the packing into the branch opening, and then pull up the tapered part with the lower end of the packing locked on the inner surface of the tube to expand the diameter of the packing by the slope of the taper, and expand the diameter of the packing to the circumference of the branch hole. Fix with the gasket pressed against the surface (for example, see JP-A-56-167986).

The techniques described in [1] and [2] above were known.

[The problem that the idea aims to solve]

However, in the prior art described in the former [1], the adhesion between the cement and the inner pipe is not so good, so the work must be done carefully when cutting out and removing the existing pipe and cement. However, there was a risk that the cement and inner pipe would easily separate from each other in areas other than the areas scheduled for removal. Additionally, since the existing pipe and a portion of the cement are removed from around the entire circumference of the pipe, the strength of the pipe as an internally treated pipe is significantly reduced in that area, and the inner pipe is exposed, making it more susceptible to damage. There is a certain inconvenience.

Therefore, in order to avoid these inconveniences,
It is necessary to protect the pipeline by covering a wide area around the opening with cement or the like, which tends to reduce work efficiency and increase costs.

In addition, the conventional technology described in the latter [2] is useful in that it can reduce the range of removal of notches in existing pipes and cement, but expensive branch joints with special configurations are required at all branch points. Therefore, an increase in costs in this respect is unavoidable.

Furthermore, with this structure, the whole thing is inserted into the branching opening with the gasket attached to the tapered part, which means that the gasket must be expanded beyond the amount set by the length of the tapered part and its slope. It is something that cannot be circumvented, and therefore,
In the case of a small-diameter tube with a relatively small inner surface treatment tube, the amount of movement of the tapered portion is very small, so there is a problem in that it is difficult to expand the diameter sufficiently.

An object of the present invention is to provide an opening structure for connecting branch pipes that is easy to work with, is cost-effective, and has a good water-stopping effect.

[Means to solve the problem]

The technical means of the present invention taken to achieve the above object is to install an inner pipe inside the pipe, and to form a branch pipe connection on the peripheral wall of the internally treated pipe with the gap between this pipe and the inner pipe filled with cement. In the structure of the opening, the outer circumferential surface of the bush that penetrates the peripheral wall of the internally treated tube is covered with a sealant, and both ends of the bush, including the sealant-coated portion, are closer to the inner circumferential surface of the inner tube. The inner tube protrudes outward from the inner surface and the outer circumferential surface of the tube, and the inner tube is prevented from coming off by pressing the opening periphery of the inner tube and the opening periphery of the tube by the outer circumferential surfaces of both ends. Both end portions are fixed in a state where the diameter is expanded so that the diameter is expanded.

[Effect]

In other words, by pressing the opening periphery of the tube and inner tube with the outer circumferential surface of the bushing whose tip has an enlarged diameter, the bushing is fixed to the internally treated tube in a manner that prevents it from coming off, and at the same time, the outer circumferential surface of the bushing A sealing material covering the inner tube is tightly attached to the inner tube, and can prevent the transport fluid from entering the peripheral edge of the opening formed in the peripheral wall of the inner surface treatment tube.

Furthermore, even if the opening of the internally treated pipe is cut and formed somewhat roughly, the cement and the internal pipe will not separate to some extent because the bush firmly presses the opening periphery of the pipe and the internal pipe. Even if this happens, the branched flow path can be maintained without any problem.

Furthermore, when forming the opening, it is only necessary to form a hole in the inner surface treatment tube that is sufficient for the bush to pass through, so it is possible to form a hole in the inner surface treatment tube that covers a wide range of area around the entire circumference of the inner surface treatment tube as in the past. There is no need to remove the cement, and there is no need to protect the pipeline. In addition, in this invention, instead of installing a branch joint with a special structure into the branch opening formed in the inner surface treatment pipe, a bush with a sealing material coating, which is extremely simple in structure, is installed. Therefore, it is possible to perform water stop treatment at a much lower cost than with conventional structures such as those using the branch joint.

In addition, the bush has both ends protruding into and out of the inner surface treatment tube, and the protruding portion is expanded, so this expansion portion depends on the diameter of the opening for branching and the inner surface treatment. It can be made large regardless of the wall thickness of the pipe, and the adhesion to the opening periphery can be sufficiently improved.

[Effect of idea]

As a result, leakage of the transportation fluid from the opening periphery of the inner pipe is prevented, and by integrating the pipe and the inner pipe, the function of the internally treated pipe can be fully demonstrated, and its deterioration can be suppressed. Now I can do it.

Furthermore, the openings can be easily formed, improving efficiency, and the protection of the conduit, which was conventionally required, can be omitted, leading to cost reductions.

Therefore, as a whole, it has become possible to provide an excellent opening structure that is easy to work with, provides a water-stopping effect, and can prevent deterioration of the inner surface treatment tube at an advantageous cost.

[Example] Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 shows a cross section of the structure of an opening for connecting a branch pipe such as a branch pipe or a merging pipe in an internally treated pipe P whose inner periphery has been repaired. Internal treatment pipe P
Existing pipes such as cast iron pipes and PC pipes 1 are examples of pipes.
An inner pipe 2 such as a polyethylene pipe is installed inside the pipe, and a milky cement 3 is filled into the gap between the inner pipe 2 and the existing pipe 1 and solidified.

A copper bush 4 that passes through an opening A formed in the peripheral wall of the internally treated pipe P is fixed to the opening for connecting the branch pipe. This bushing 4 is positioned so that its both ends protrude inward from the inner peripheral surface of the inner pipe 2 and outward from the outer peripheral surface of the existing pipe 1, and its entire diameter is expanded to meet the inner surface of the opening. While being crimped, both end portions 4a and 4b are bent and enlarged in diameter. And these both enlarged diameter portions 4
By pressing the opening periphery 2a of the inner pipe 2 and the opening periphery 1a of the existing pipe 1 with the outer circumferential surfaces of a and 4b, the bush 4 is fixed in position without coming off, and the inner pipe 2 and the cement 3 are It is designed to prevent peeling.

The outer peripheral surface of the bush 4 is covered with a sealing material 5, and the bushing 4 is pressed against the opening periphery 2a of the inner tube 2 to prevent it from coming off, and at the same time, the sealing material 5 is tightly attached to the inner tube 2. The transport fluid passing through the inner surface treatment tube P is prevented from leaking to the peripheral edge of the opening A formed in the peripheral wall of the inner surface treatment tube P. Therefore, it is possible to prevent the transport fluid from entering the contact surface between the cement 3 and the inner pipe 2, and to prevent the transport fluid from leaking to the outside through the three cement layers.

Next, the procedure for constructing the branch pipe connection opening having the above structure will be explained.

First, as shown in Figure 2A, the inner surface treatment tube P
Attach the cap 6 for connecting the branch pipe to. In the figure, 7 is an annular sealing material. Subsequently, as shown in FIG. 2B, an opening A is bored in the peripheral wall of the inner surface treatment tube P. Then, as shown in FIG. 2C, this opening A
A bush 4 whose outer peripheral surface is covered with a sealing material 5 is inserted into the bush 4 . Thereafter, as shown in FIG. 2D, the diameter of the entire bush 4 is expanded using a bush diameter expander 8, and at the same time, both tip portions 4a and 4b are bent outward, and the outer circumferential surface of the bush 4 is expanded into the inner tube 2. and press against the opening peripheral portions 2a, 1a of the existing pipe 1.

The bush diameter expander 8 includes a rod 9 with a flat plate 9a attached to its tip, and a cylindrical member 1 into which the rod 9 is fitted.
0, and the flat plate 9a at the tip of the rod 9 and the cylindrical member 1
Thick-walled cylindrical elastic resistance 11 made of rubber etc. interposed between
It is made up of When expanding the diameter of the bush 4 and bending both end portions 4a and 4b, the bush diameter expander 8 is inserted into the bush 4, and the rod 9 is pulled upward in the figure with the cylindrical member 10 fixed. . Then, the flat plate 9a at the tip of the rod 9
By applying pressure with the cylindrical member 10 and elastically deforming the thick cylindrical elastic body 11 outward in the radial direction of the bush diameter expander 8, the entire diameter of the bush 4 is expanded and both tip portions are expanded. 4a and 4b are each bent outward to enlarge the diameter. When the diameter expansion is completed, the pressure on the thick-walled cylindrical elastic body 11 is released, and the bush diameter expansion tool 8 is pulled out from the bush 4.

Thereafter, the branch pipe 12 is fixed to the metal fitting 6 with bolts, and the connected state of the branch pipe 12 shown in FIG. 1 is obtained.
In the figure, 13 is an annular sealing material.

The material, shape, etc. of the bush 4 can be changed as appropriate. For example, when the bush 4 with a positioning flange processed and formed is positioned in the opening A, the flange of the bush 4 comes into contact with the outer peripheral surface of the existing pipe 1 and automatically It is also preferable that the insertion depth of the bush 4 can be determined according to the timing.

The inner surface treatment pipe P can be used as a water pipe, a sewer pipe, a gas pipe, or the like.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 show an embodiment of the opening structure for connecting a branch pipe in an internally treated pipe according to the present invention,
FIG. 1 is a sectional view of a branch pipe connecting portion, and FIGS. 2A to 2D are sectional views showing the branch pipe connection process. FIG. 3 is a sectional view corresponding to FIG. 1 showing a conventional example. DESCRIPTION OF SYMBOLS 1... Pipe, 1a... Opening periphery of tube, 2... Inner pipe, 2a... Opening periphery of inner pipe, 3... Cement, 4... Bush, 4a, 4b... Tip portion of bush, 5... Sealing material, P... Inner surface treatment tube, A... Opening formed in the peripheral wall of the inner surface treatment tube.

Claims (1)

[Scope of claim for utility model registration] In addition to installing the inner pipe 2 in the pipe 1, this pipe 1
A structure of a branch pipe connection opening formed in the peripheral wall of the internally treated pipe P in which the gap between the internally treated pipe P and the internally treated pipe P is filled with cement 3, and a bush 4 that penetrates the peripheral wall of the internally treated pipe P.
The outer circumferential surface of the bushing 4 is covered with a sealing material 5, and both ends of the bushing 4, including the portion covered with the sealing material 5, are on the inner side of the inner circumferential surface of the inner tube 2 and on the outer side of the outer circumferential surface of the tube 1. It is prevented from coming off by pressing the opening periphery 2a of the inner tube 2 and the opening periphery 1a of the tube 1 by the outer circumferential surfaces of both end portions 4a and 4b of the inner tube 2 and the opening periphery 1a of the tube 1. , an opening structure for connecting a branch pipe in an internally treated pipe in which both end portions 4a and 4b are fixed in an enlarged state.