JPH0230891A - Method and apparatus for replacing underground buried pipe - Google Patents

Abstract

PURPOSE:To easily replace pipes under the ground by new pipes without a large-size propulsory machine by a method in which a precede pipe is advanced while cutting off an existing pipe under the ground from inside, a temporary pipe is set on the back side, and the temporary pipe is replaced by a new pipe. CONSTITUTION:A precede pipe A with a cutter bit is advanced while cutting off an existing pipe (a) buried under the ground from inside, and the excavated muck is removed from inside of the pipe A. A temporary pipe (f) is connected to the pipe A for placing it to the muck-removed places in order. The pipe (f) is then replaced by a new pipe (g).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to, for example, renewal of aging sewer pipes,
This article relates to a construction method and equipment for re-laying underground pipes.

[Conventional technology]

Conventionally, the open-cut method was used to replace existing pipes by excavating the old pipes and replacing them with new pipes, but this method had the drawbacks of causing traffic congestion and being prone to problems such as loosening of the ground. .

For this reason, various construction methods that do not involve excavation have been devised.

The first method is the so-called pipe-in-pipe method, in which a pipe with a diameter one size smaller than the existing length is inserted.

However, with this construction method, the diameter of the new pipe is smaller than the diameter of the existing pipe, which reduces the flow rate, and in the case of sewer pipes, the bottom height of the pipe increases, causing problems in relation to the pipes before and after it. there's a possibility that.

Furthermore, as a construction method to prevent the occurrence of this problem, there is a construction method using crushing such as expansion crushing and compression crushing, in which the old pipe is expanded and crushed, and then a new pipe is installed.
30, JP 62-125197, JP 62-146395, JP 60-160978
It is disclosed in the publication number etc.

In addition, the extrusion method and traction method, in which the existing pipe is pushed out with a new pipe or pulled out from the other end, are disclosed in Japanese Patent Application Laid-Open No. 62-1374.
It is disclosed in JP-A No. 86, JP-A-62-112894, JP-A-62-35188, JP-A-62-25697, etc.

Furthermore, as described in Japanese Patent Application Laid-open No. 61-33818, a construction method for digging around a buried pipe,
There is also a method of turning the inner surface of a buried pipe, as described in Japanese Patent No. 85.

[Problem to be solved by the invention]

However, when applying the above-mentioned crushing method, if the concrete contains reinforcing bars or if the connecting collar is made of steel, it cannot be easily crushed, and if the crushing method is applied using impact force, it may cause vibration pollution. There is also a risk of being triggered.

In addition, with the above extrusion method and traction method, the frictional force between the soil and the pipe is extremely large due to long-term burial, and there are problems with the location where the reaction force is taken and the strength of the pipe, and it is also possible to remove it by applying shock or vibration. However, it generates noise, which is not desirable.

The problem to be solved by the present invention is to solve the problems of conventional construction methods when replacing underground pipes, and to crush underground pipes with connecting collars in addition to reinforced concrete pipes, ceramic pipes, PVC pipes, etc. The purpose is to eliminate rock fragments and earth and sand, improve excavation efficiency, and also ensure that re-laying can be carried out without causing any damage to the surrounding area.

[Means to solve the problem]

To replace the underground pipe of the present invention, the underground pipe is excavated from the inner peripheral surface using a cutter bit installed in the lead pipe, and the excavated debris from the excavation is removed from the inside of the lead pipe. The above problem was solved by propelling and burying the new pipe in the removal section using a propulsion device.

〔Example〕

1 to 3 show the structure of a bit attached to a cutter head applied to the construction method of the present invention, and FIGS. 4 to 5 show the structure of the cutter head and its usage mode.

FIG. 1 shows the appearance of the cutter bit 1 described above.

In the figure, 2 indicates a main blade provided on the outer periphery of the truncated conical main body 3. The main blade 2 is usually made integrally with the main body 3 from high tensile strength alloy steel or the like.

FIG. 2 shows a cutaway view of FIG. 1 viewed from the direction of the line ■-■.

As shown in the figure, the main blade 2 provided on the outer periphery of the truncated conical main body 3 has a first blade row 21 arranged in a cross shape on the outer periphery of the main body 3. 21 and a second row of blades 22, which are arranged exactly 45 degrees apart, are arranged in three rows alternately in the direction of the rotation axis. Reference numeral 4 indicates a hole drilled at the bottom of the blade between the main blades 2, through which waste from the excavated existing pipe is transferred.

The arrangement and shape of the transfer hole 4 are based on the following points: the main blade at the tip plays a leading role in primary crushing of old pipes and rock, and the main blade in the last row plays a role in expanding the propulsion machine track.
It is preferable to provide one blade between each month 2 in each blade row 21 and 22, except for the front row and the rear row.

FIG. 3 is a diagram showing the longitudinal cross-sectional structure of the cutter bit l. Referring to the figure, a lumen 7 is formed in the interior thereof, which communicates with a pressure fluid supply hole 5 provided at the tip and a soil removal hole 6 provided at the rear end, and furthermore, the transfer hole 3 is connected to the Same internal cavity part 7
is connected to.

FIG. 4 is a cross-sectional view of the cutter head 10 in which the cutter bit 1 of the present invention is attached to the leading tube A, and FIG. 5 is a front view of the cutter head IO.

Referring to these figures, generally four cutter heads 10 are rotatably mounted via bearings D around a rear shaft C of a guide casing B at the tip to the leading pipe. The compressed fluid, usually compressed air, in the leading pipe A communicates with the compressed fluid supply hole 5 of the cutter bit 1 via the rotary seal ring F, and the soil discharge hole 6 at the rear end is connected to the leading pipe. It opens to the discharge port G of. As shown in FIG. 5, the cutter bit 1 is attached to the cutter head 10 so that the maximum radius R corresponds to the radius of the existing pipe a.

This allows the driver installed inside the lead pipe (
By rotating the cutter bit l by the rotation of the drill bit (not shown), the lead pipe A penetrates through the underground pipe A by the thrust of the propulsion machine while the rock cutting blade 2 crushes the underground pipe a. The crushed pipe pieces and earth and sand are sucked into the internal cavity 7 of the cutter bit 1 through the suction hole 4 of the cutter bit 1, and at the same time, pressure fluid is supplied through the pressure fluid supply hole 5 at the tip of the cutter bit 1. is press-fitted, the pipe fragments and earth and sand are transferred to the inside of the lead pipe A, and the amount of pipe debris and earth and sand that accumulates in the lead pipe type is reduced, so the penetration and frictional resistance of the lead pipe A is reduced, and the propulsion Increase speed and improve propulsion effect.

FIG. 6 to FIG. 8 are diagrams showing the embodiment of the construction method of the present invention in order of steps.

FIG. 6 shows a state in which an existing pipe a is excavated by the cutter head 10 of the present invention. In the figure, a plurality of existing pipes a are laid between a manhole b on the departure side and a manhole C on the arrival side. d shows the starting casing built near the starting side manhole C.

First, when replacing the existing pipe a, a small-diameter propulsion machine e is installed in this starting casing d, and the
The cutter 10 shown in FIG. 5 is rotated and propelled by a propulsion device e. As the small diameter propulsion device 12, in the specification of Japanese Patent Application No. 198213/1982,
It is preferable to use the propulsion device disclosed by the applicant.

Then, while propelling a leading pipe type with a cutter head 10 attached to the tip inside the existing pipe a by a propulsion device e, the existing pipe a is excavated, the excavated waste of the existing pipe a is discharged from the rear, and the temporary pipe is Connect f to the leading pipe Δ.

FIG. 7 shows that the cutter head 10 shown in FIG. 6' is propelled to reach the reaching manhole C, and a temporary pipe is connected between the starting casing d and the reaching manhole C in a leading pipe manner. This shows the state replaced by f.

FIG. 8 shows a state in which the new main pipe g is being propelled by the propeller e to replace the temporary pipe f.

In this way, the existing pipe a is excavated and removed from the inside,
A temporary pipe was installed in the removed area, and a propulsion machine was used to
The tracheal tube is pushed out by the new tube to the destination man-ball, and a new tube is installed in its wake.

〔Effect of the invention〕

The following effects can be achieved by the present invention.

(1) The existing pipe is scraped from the inside and the scraps are discharged from the propulsion casing to the outside.
Replacement/exchange becomes possible.

(2) Since a large reaction force is not required for replacement, a special propulsion machine is not required, and a conventional small-diameter propulsion machine can be used.

(3) Since the cutter head itself has soil removal capability, the excavation propulsion effect is dramatically improved.

(4) Less noise is generated due to vibrations, etc.

[Brief explanation of the drawing]

The accompanying drawings illustrate embodiments of the invention. 1 to 5 show the cutter head of the present invention;
Figures 8 to 8 are diagrams showing the process of replacing the buried pipe using the cutter head. : Cutter bit: Bit body: Pressure fluid supply hole: Inner cavity: Cutter head: First blade row 2: Main blade 4: Earth and sand transfer hole 6: Discharge hole 22: Second blade row Patent applicant Kyoei Doken Co., Ltd.

Claims (1)

[Scope of Claims] 1. Excavating an underground pipe from the inner circumferential surface using a cutter bit provided in the leading pipe, removing the excavated debris from the inside of the leading pipe, and propelling it to the removal section. A method for replacing underground pipes, which is characterized by propelling and burying new pipes using a machine. 2. A main blade row is arranged in the direction of the rotation axis, and a dirt transfer hole is bored in the bottom of the main blade row, and a bore is provided inside the cutter bit, and a pressure fluid supply hole provided at the tip and a rear A re-laying device for an underground pipe, characterized in that a discharge hole provided at an end, and a discharge hole and a transfer hole are respectively communicated with the inner cavity.