JPS58160693A - Method of executing branch pipe in method of pipe-in-pipe construction - 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 new construction method for branch pipes in the so-called pipe-in-pipe construction method, in which a steel pipe is drawn into an existing pipe to create a new pipe line.

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 road.

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

However, in places where a branch pipe is connected to an existing pipe, a method for connecting the newly rehabilitated pipe to the branch pipe has not been developed. Therefore, the construction costs were relatively high and the construction period was long.

In order to eliminate the above-mentioned drawbacks of the conventional technology, the present invention has developed a method for connecting branch pipes so that the bi-one pipe construction method can be applied to existing pipes to which branch pipes are connected. The explanation will be based on.

Fig. 1 is a cross-sectional view of the central part of a branch pipe showing an embodiment of the present invention, and inside the existing pipe (1) to which the branch pipe (2) is connected, a prayer pipe is installed using the known pipe-in-pipe construction method. A rehabilitated pipe (3) made of steel pipe that serves as a road is drawn in and held concentrically with wheels or special fittings (not shown), and a branch pipe is installed at a position corresponding to the branch pipe (2) of the rehabilitated pipe (3). (2)
A round hole (4) with a diameter larger than the inner diameter of the hole is bored.

Then, a straight rehabilitated single pipe (6) having a required length and an outer diameter slightly smaller than the inner diameter of the branch pipe (2) is connected to the small-diameter end of the tapered tubular reducer (7), and the reducer - A seal gasket (7) with a ■-shaped cross section, whose rounded rear end is secured by the gasket fastener (9).
8) is attached to the rehabilitation tube (3).
Insert into the branch pipe (2) through the round hole (4) from the inside, and insert the 7-growth gasket (8) attached to the outer periphery of the reducer (7) of the insertion pipe (5) into the entire existing pipe (1). The gap in the inner circumference of the branch pipe (2) is sealed by crimping the peripheral surface, and the large diameter end of the resin kneecer (7) is connected to the round hole (4).
The peripheral part is welded to the rehabilitation pipe (3).

After that, mortar 01 or the like is injected into the gap between the outer periphery of the rehabilitated pipe (3) and the inner periphery of the existing pipe (1) using a known grout hole method or injection pipe method. It is provided so that it is pressed into the gap and self-seals.

Note that the seal packing (8) is not limited to the structure shown in the drawings, and may have other seal structures.

Since the present invention is configured as described above, the buy-in-pipe construction method can be applied not only to existing pipes and branch pipes made of steel pipes but also to cases where they are made of non-weldable materials such as concrete pipes or cast iron pipes. The branch pipe connection part can be reliably and firmly constructed from inside the rehabilitated pipe of the new pipe, thus reducing construction costs and shortening the construction period.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the central part of branching snow showing an embodiment of the present invention. l: Existing pipe, 2: Branch pipe, 8: Rehabilitation pipe, 4: Round hole, 5:
Insertion pipe, 6: Rehabilitated single pipe, 7: Reducer, 8 Niji-μ
Patchkin, 9: Patchkin fastener, lO2 mortar Figure 1

Claims (1)

[Claims] (1) In the pipe-in-pipe construction method in which a rehabilitated pipe (3) is drawn into the existing pipe (1) to which the branch pipe (2) is connected to create a new pipe, the pipe is drawn into the existing pipe (1). A round hole (4) is bored in the corresponding position of the rehabilitated pipe (3) & branch pipe (2), and the rehabilitated single pipe (6) with an outer diameter slightly smaller than the inner diameter of the branch pipe (2) is inserted into the Y juicer ( Connect to the small diameter end of the reducer (7) and attach a packing stopper (
9) Attach the seal gasket (8) with the rear end suspended! Insert 'IF (5)'e, said round hole (4
) into the branch pipe (2) and seal the seal packing (
8) to the inner circumferential surface of the existing pipe (1), and after welding the large diameter end of the resin knee (7) to the rehabilitated pipe (3), the outer circumferential gap of the rehabilitated pipe (3) is A branch pipe construction method in the pipe-in-pipe construction method, which is characterized by filling the pipe with 7-ply yva* or the like.