JPS58146783A - Method of communicating connecting section of pipe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called pipe-in-pipe construction method in which a steel pipe is drawn into an existing pipe to create a new pipe, and the present invention provides a method for connecting the end of the steel pipe drawn into the existing pipe and the existing pipe. It is about the method.

Conventionally, for example, when a water distribution pipe buried underground became obsolete, the old existing pipe was removed by excavating the entire surface of the road, and then a new pipe of the same diameter as the existing pipe was installed in its place. However, due to recent deterioration in road traffic conditions and pollution problems such as noise and vibration caused by excavation work, it is becoming extremely difficult to excavate the entire surface of the road.

Therefore, recently, the so-called pipe-in-by 1 method has been developed, which uses the existing pipe as a sheath pipe and draws a slightly smaller diameter steel pipe into it to create a new pipe line without removing the old pipe. It is becoming popular.

By the way, in the above-mentioned by-one-in-by-one construction method, existing pipes are used as part of the conduit in areas where the existing pipes can still be used or in areas where they are connected to valve chambers, etc.
It is necessary to connect the end of the drawn-in steel pipe and the inner peripheral part of the existing pipe except for that part so that the internal fluid can flow smoothly.

In this case, if the existing pipe is a steel pipe, as shown in Figure 1, the small-diameter end of the tapered snowflake (3) is welded to the end of the steel pipe (2) that has been pulled into a predetermined position. , after welding the large diameter side end to the inner peripheral part of the existing steel pipe W (1), the steel pipe (2)
The gap between the outer periphery of the fallen pipe (3) and the inner periphery of the existing steel pipe (1) is filled with mortar (4) etc. to connect the connection part, but the existing pipe is made of non-weldable materials such as concrete and cast iron. In this case, it was impossible to fix the single drop pipe, and the above connection method could not be applied because of the intrusion of internal fluid into the mortar.

In view of the above-mentioned conventional circumstances, the present invention provides a by-one-in-by-one construction method in which a steel pipe is drawn into an existing pipe made of a non-weldable material to create a new pipe. After sealing the gap with the inner periphery of the pipe using a sealing device, fill the outer periphery of the steel pipe with mortar, etc., and then connect the large diameter side of the tapered single drop to the inner periphery of the existing pipe, and weld the small diameter side to the end of the steel pipe. After that, a water-resistant grouting agent is filled into the outer circumferential gap of the falling pipe.

Fig. 2 and Fig. 8 show one embodiment of the present invention, Fig. 2 is a longitudinal sectional view, Fig. 8 is an enlarged view of section m in Fig. 2, and the existing pipe (5) is made of concrete, cast iron, etc. It is made of a non-weldable material, and a steel pipe (6) is drawn into it, and the wheels (not shown) are held concentrically with sliding fittings. After sealing the gap between the inner periphery of the pipe (5) and the outer periphery of the steel pipe (6) (usually 80 to 100 M) using the sealing device (7), fill the outer periphery gap of the steel pipe (6) with mortar 1v (2), etc. be.

The sealing device (7) is a ring-shaped packing made of an elastic material such as rubber or synthetic resin between the packing seat (8) fixed to the outer periphery of the end of the steel pipe (6) and the holding ring (9).
0 is inserted and tightened with a bolt Ql), so that the packing 0Q is crimped and sealed to the outer periphery of the steel pipe (6) and the inner periphery of the existing pipe (5), but the present invention is not limited to this. , other seal structures may also be used.

In order to facilitate handling, the sealing device (i) may be provided in advance on the outer periphery of a short steel pipe and welded to the end of the steel pipe (6) into which the short steel pipe is drawn.

Next, to the end of the steel pipe (6), weld the small-diameter end of a half-fall pipe a3, which has been cut into two or three in the circumferential direction and has a suitable tapered shape, and the outer periphery of the large-diameter side is welded to the end of the existing pipe (6). 5) It should be in contact with the inner periphery.

After that, a grouting agent (b) made of synthetic resin with excellent water resistance is applied to the gap between the outer periphery of the fallen pipe (6) and the inner periphery of the existing pipe (5). is injected/filled with a grout pump etc. from the injection port (to) provided in the single drop pipe (to), and as the grouting agent A19 solidifies, the single drop pipe (to)
and the existing pipe (5) are strongly integrated.

Note that it is desirable to apply primer (undercoat) to the inner circumferential surface of the existing pipe (5) in advance in order to improve the adhesion of the grout agent α.

Since the present invention is constructed as described above, even if the existing pipe is made of a non-weldable material, the connection with the end of the lead-in steel pipe can be made reliable and strong, and the resistance to fluid can be reduced.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view for explaining the connection method when the existing pipe is a steel pipe, Fig. 2 and Fig. 8 show an embodiment of the present invention, and Fig. 2 is a longitudinal cross-sectional view; FIG. 8 is an enlarged view of section m in FIG. 2. l: existing steel pipe, 2: steel pipe, 8: fallen pipe, 4: mortar,
5: Existing pipe, 6: Steel pipe, 7: Seal device, 8: Packing seat, 9: Holding ring, 10: Packing, ll: Bolt,
12: Mortar, 18: Slab pipe, 14 Nigeraud agent, 1
5: Inlet applicant Sumitomo Metal Industries Co., Ltd. Applicant Sumikin Steel Pipe Works Co., Ltd. Figure I Figure 21!1 Figure 3 A

Claims (1)

[Claims] (1) Conch! J-), in the by-one-in-pipe construction method in which a steel pipe (6) is drawn into an existing pipe (5) made of a non-weldable material such as cast iron to create a new pipe, the steel pipe (6) is drawn into the existing pipe (5). Steel! (6) and the existing pipe (5)
) After sealing the gap with the inner circumference with the sealing device (7),
The outer gap of the steel pipe (6) is filled with 7-ri/I' (2), etc., and the large diameter side of the tapered snow flake (to) is filled with the existing pipe (
5) After welding the small diameter side to the end of the steel pipe (6) in contact with the inner periphery, apply water-resistant grout α◆ to the outer periphery gap of the falling pipe (toward).
A method for connecting pipe connections, characterized by filling the joints with.