JP2003129790A - Method and device for constructing pit mouth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method for a pit mouth, which adapts to a reduction in the diameter of a pit. SOLUTION: In a pipe burying construction method for pushing and burying a small-bore pipe into ground, after the erection of a pit frame 13, a cut-off pit mouth opening 12 is formed in a side wall; a pipe burying apparatus 1, which is equipped with a drive part 4 for rotating and driving an auger screw 5 for excavation and a propulsive device 18 for propelling a pipe, is installed in a bottom part of the opening 12; and by virtue of the propulsive device 18, a casing 11 with a cut-off pit mouth is fixed by a packing retainer of the opening 12, welding 25 and like, so that the cut-off pit mouth can be constructed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a wellhead and a device therefor, which enables a long pipe length to be buried even though it is a small vertical shaft in the pipe burying method and can be applied to a spring ground.

[0002]

2. Description of the Related Art Conventionally, a pipe burying device has been installed in a shaft excavated from the surface of the earth as a means for horizontally burying a relatively small-diameter pipe such as a water supply and sewer or a conduit pipe in the ground. A method in which pipes are successively added and embedded by excavating the ground and pushing and propelling the pipes from the rear is widely used. In the pipe burying device 1, as schematically shown in FIG. 8, a drive unit 4 is installed on a guide rail 3 in a shaft 2 excavated from the surface of the shaft so that the drive unit 4 can move back and forth. It is rotationally driven to excavate the ground by the auger head 6 at the tip thereof, and the propulsion device 7 (propulsion cylinder) pushes in the pipes 10, 10 ... By doing so, the pipe 10 is buried in the ground.

[0003]

However, in recent years, construction work has been increasing at a narrow site such as in the vicinity of a residential area. Therefore, the work site, especially the shaft 2 where the pipe burying mechanism is installed, is excavated. The space available is limited and it is extremely difficult to excavate large shafts.

Under these circumstances, when only a small-diameter shaft can be excavated, the pipe length that allows the buried pipe to be added is restricted, and the work of adding the pipe 10 at the time of construction is increased, and the pipe 10 is increased. Since the length is short, the work efficiency is low and the cost is high.

Further, it is necessary to downsize the pipe burying device in order to cope with a small-diameter shaft, but downsizing of the pipe burying device has already reached its limit, and further downsizing cannot be achieved. Nearly impossible.

In view of the above points, the present invention provides a construction method and apparatus which can improve the construction of the shaft itself so that the pipe material can be used as long as possible, and can be applied even if the shaft is installed in a spring ground. It was done as an issue.

[0007]

As a means for solving the above problems, the present invention is a pipe burying method for burying and burying a small diameter pipe in the ground, in which a vertical shaft frame is erected from the ground and a side wall has an opening for a well hole. Is formed and is projected to the outer side surface of the opening for the well hole of the shaft frame to construct a still water well hole.

Incidentally, in detail, a shaft frame is built from the ground,
After forming a wellhead opening on the side wall, a water blocking packing is installed in the opening together with a packing retainer, and a pipe burying device equipped with a driving unit for rotating the excavating auger screw and a propulsion device for propelling the pipe at the bottom of the packing. Installed, the casing with a water stop pit is embedded in the ground through the opening for the pit by the propulsion device, and after the filling, the rear end and the water seal packing retainer are partially fixed by welding or the like to stop the water. It is designed to form a wellhead.

[0009] Further, if the casing is provided with a water stop pit with rotation by the drive unit, and the ground is excavated by the face formed at the tip of the casing with a water stop pit, the thrust is embedded by the propulsion device. Construction can be performed more efficiently.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings.

1 to 5 are plan views showing steps of the wellhead construction method according to the present invention.

First, a vertical hole is cut in a predetermined place to form a vertical shaft frame 1
3 is built in the vertical direction to construct the vertical shaft 2, and then the left and right guide rails 3 of the pipe embedding device 1 are installed in the lower portion of the vertical shaft 2 and the drive unit 4 is mounted on the guide rail 3 so as to be movable back and forth. At the same time, the left and right propulsion cylinders 7 for moving the rotary pressing plate 19 and the drive unit 4 forward and backward are installed as usual.

Next, attach the wellhead casing to the propulsion unit,
The opening 12 for a wellhead is formed on the side wall of the vertical shaft frame 13 by a method such as fusing so that the casing 11 with a stillhole mouth can be inserted as densely as possible.

When this shaft is built in a spring ground, the outer side of the vicinity of the planned opening 12 for the wellhead is improved by a chemical injection method according to a standard method before the fusing opening 12 for the wellhead is formed, and the opening for the wellhead is opened. Temporarily prevent spring water from flowing into the vertical shaft when the part 12 is formed.

After that, the formed wellhead opening 12 is formed.
Then, a water blocking packing 17 'is fixedly installed together with a packing retainer 18' with a bolt 21 'or the like to form a water blocking well mouth opening 12'.

The rotational force generated by the motor mounted on the drive unit 4 is transmitted to the casing 11 with a water stop hole through the screw shaft 5'of the front conduit 9 and the clutch panel 6a of the auger head 6, and is stopped when the water stop hole is constructed. Casing with water port 11
Is driven to rotate. In this clutch mechanism, as shown in FIG. 7, the excavation force transmission member 6b is in a fixed position, and the auger head is provided with a groove that is movable in the axial direction. Since the head moves to the left, the wellhead casing 11 no longer rotates.

Further, the casing 11 with a still water well opening is provided with a rotating pressure plate 19 and a well mouth casing mounting portion 16 for fixing the rear end, and the casing mounting portion 21 with a still water well opening has a different outer diameter. Multiple types (eg 200φ, 2
In order to be able to correspond to the casing 11 with a still water well opening of 50φ, 300φ), in the drawing, there are three types of mounting portions 21 having different diameters. Then, the casing 1 with a still water well opening is attached to one of the mounting portions 21 corresponding to the outer diameter of the casing 11 with a still water well opening.
The rear end of 1 is fixed by a bolt 22.

In the casing 11 with a water stop pit, a spiral screw blade 15 is provided on the inner periphery of the tip side over a few rounds, and excavated earth and sand is discharged by the screw blade 15 and the inside of the front conduit 9 is discharged. It is designed to be carried out through the shaft 2 through the shaft.

In the case of soft ground or the like, the screw blades 15 can be eliminated. In that case, the rotary excavation of the auger head and the rotary pressing plate 19 by the propulsion cylinder 7 are performed.
It is possible to push the casing 11 with a water stop pit into the ground by the pushing force of the.

Therefore, first, as shown in FIG. 1, in a state where the drive unit 4 is retracted, the rotary pressing plate 19 is fitted into a portion corresponding to the diameter of the water stop pit casing mounting portion 16 and fixed by the bolt 21 '. Next, the propulsion cylinder 7 is extended to move the casing 11 with the water stop hole to the water stop hole opening 12 of the shaft frame 13.
And the rotational force of the drive unit 4 is transmitted to the casing with water stop hole 11 via the clutch shaft 6a of the auger head 6 via the screw shaft of the leading conduit, and the casing with water stop hole 1
1 is rotationally driven, and the rotary pressing plate 19 is moved forward by the propulsion cylinder 7.

As a result, the ground is excavated by the tip screw blades 15 of the casing 11 with a still water pit and the cutting edge 14 at the tip of the tip conduit 9 to enter the ground, and the excavated earth and sand is inside the casing 11 with a still pit. It is discharged and collected in the vertical shaft 2 through the inside of the front conduit 9 via the screw blade 15 of FIG.

When the propelling cylinder 7 pushes the rotary pressing plate 19 away, the casing with a water stop shaft 11 is separated, and the propelling cylinder 7 is moved in a shortened manner so that the rotary pressing plate 19 and the drive unit 4 are retracted. Casing with wellhead 1
A rear end of the outer periphery of 1 and the portion of the water blocking packing presser 18 'are partially fixed by welding 22 or the like to form a water blocking pit. As for this fixation, the casing 11 with a still pit mouth is connected to the front conduit 9 and the buried pipe 10.
The movement of the casing 11 with a water stop shaft is prevented by the frictional force between the pipe and the water seal packing 27 at the time of the movement, and only a part thereof may be used.

Incidentally, the casing 1 with a still water well opening in which the outer peripheral rear end of the casing 11 with a still water well opening and the water tight packing pressing portion 18 'are partially fixed by welding or the like to form the water well opening.
The disturbing part in the shaft 2 of 1 is cut off (Fig. 3).

The water blocking packings 17 and 17 'are made of rubber, synthetic resin or the like, and the inner circumference thereof is in close contact with the outer circumferential surface of the pipe 10 to be buried so that the spring water generated when the pipes are buried inside the vertical shaft 2. Block inflow.

After that, the casing mounting portion 16 with the still water inlet is removed from the rotary pressing plate 19, and the auger screw 5 and the pipe 10 to be buried are set instead, and the pipe 10 and the auger screw 5 already buried. And push the pipe 10 forward by extending the propulsion cylinder 7

At this time, the pipe 10 is the casing 1 with a still water pit mouth.
1, and the outer peripheral surface is placed in a water-stop state by water-stop packing 27 and pushed (FIG. 4).

As described above, since the water stop pit is constructed so that it does not project into the vertical shaft 2 at all, the inner diameter of the vertical shaft 11 can be fully used to suspend and connect the pipe 10, and the vertical shaft 2
It is possible to use a tube having a longer tube length than that of the conventional tube.

Further, the vertical shaft 2 and the casing 11 with the still water shaft entrance.
Also, the casing 11 with a still water pit mouth and the buried pipe 10 are protected by the water sealing packings 17 and 17 ', so that construction can be performed without problems even in the case of spring ground.

In the illustrated example, the vertical shaft 2 is shown as a perfect circle, but even if the vertical shaft has a shape other than a perfect circle, the water stop hole can be constructed in the same manner.

[0030]

As described above, according to the present invention, since the water stop pit is constructed so as to project from the vertical shaft into the ground,
Since the wellhead never projects into the vertical shaft, it is possible to effectively cope with the downsizing of the vertical shaft.

In the spring ground, the vertical shaft, the casing with the still water well mouth, the casing with the still water well mouth, and the buried pipe are protected by the waterproof packing, so that the construction can be carried out without any problem.

Further, according to a second aspect of the present invention, the casing with a still water well mouth is buried so as to project from the vertical shaft into the ground by utilizing the drive unit and the propulsion mechanism of the pipe burying device. If it is fixed to the vertical shaft frame by welding, etc., it can be constructed by utilizing the function of the pipe burying device without the need for manual digging work of the wellhead, and the risk of falling tables and water can be avoided. .

Moreover, since there is no manual digging, it is possible to construct a water stop pit accurately and in a short time, thereby improving work efficiency and reducing cost.

According to the third aspect of the present invention, when the wellhead casing is buried, it is inserted into the ground while being rotated by the driving portion of the pipe burying device, so that the wellhole can be constructed more efficiently.

[Brief description of drawings]

FIG. 1 is a plan view showing a state immediately before the start of construction of a still water well.

FIG. 2 is a drawing showing a state in which a casing with a water stop pit is pushed into the ground.

FIG. 3 is a plan view showing the completion of construction of a still water well entrance.

FIG. 4 is a plan view showing a state before pushing in a pipe to be buried.

FIG. 5 is a plan view showing a pushed-in state of a pipe to be buried.

FIG. 6 is an enlarged view of part A in FIG. Enlarged view of part B.

FIG. 7 is a schematic diagram of a clutch mechanism.

FIG. 8 is a side view showing an outline of a pipe burying device.

[Explanation of symbols]

1 Pipe burying device 2 shafts 4 drive 5 auger screw 6 Auger head 7 Propulsion device (cylinder) 8 blades 9 Destination conduit 10 pipes (buried pipes) 11 Casing with still water pit 12,12 'Wellhead opening, still water wellhead opening 13 Vertical shaft frame 14 cutting edge 15 Casing screw blade 16 Wellhead casing mounting part 17,17 'Water-stop packing 18, 18 'Packing foot 19 Rotating pressure plate

Claims (6)

[Claims] 1. A pipe burying method for squeezing and burying a small-diameter pipe in the ground, in which a shaft frame is built from the ground, an opening for a shaft is provided in this shaft frame, and the shaft is constructed by projecting to the outer surface side of the shaft. A wellhead construction method characterized by that. 2. A pipe burying method for squeezing and burying a small-diameter pipe in the ground, in which a vertical shaft frame is erected from the ground, a vertical shaft is provided with a water stop shaft for casing, and an auger screw for excavation is rotationally driven at the bottom thereof. A pipe burying device including a drive unit for driving the pipe and a propulsion device for propelling the pipe is installed, and the casing with a water stop pit is embedded into the ground from the water stop pit for the casing by the propulsion device. And a part of an outer edge of the packing presser of the water stop well for the casing are fixed by welding or bolting to form the water stop well construction method. 3. The casing is provided with rotation through the drive unit via a clutch plate, and is pushed by the propulsion device while excavating the ground by a cutting blade formed at the tip of the casing with water stop well. The wellhead construction method according to claim 2, which is configured to be buried. 4. In a pipe burying method for squeezing and burying a small-diameter pipe in the ground, a vertical shaft frame is erected from the ground, a water stop shaft for casing is provided in the vertical shaft frame, and an auger screw for excavation is rotationally driven at the bottom thereof. A pipe burying device including a drive unit for driving the pipe and a propulsion device for propelling the pipe is installed, and the casing with a water stop pit is embedded into the ground from the water stop pit for the casing by the propulsion device. And a part of the outer edge of the packing retainer of the water stop well for the casing are fixed by welding or bolting to form the water stop well. 5. The pipe burying device according to claim 4, wherein the casing mounting portion with a still water well mouth of the propulsion device has a plurality of types of mounting portions corresponding to the still water well mouth casings having a plurality of pipe diameters. 6. The pipe burying device according to claim 4, wherein the casing with a water stop pit has a cutting blade at the tip thereof and a ring-shaped screw blade for sending the excavated earth and sand backward to the inner periphery of the tip portion.