JPH07103545B2 - Sleeve pipe installation device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is based on a sleeve injection method.
The present invention relates to a sleeve pipe erection device applied to ground improvement .

[0002]

[Prior art and its problems] The sleeve injection method is
Install a sleeve pipe (outer pipe) as an injection pipe in the
The inner pipe for injection equipped with the lupacker is placed in the sleeve pipe.
This is a method of inserting and injecting a chemical solution at an arbitrary position.

The ground improvement method by sleeve injection has already left a lot of construction results, and the construction process is schematically shown in FIG. In FIG. 5, from the left,
Boring process with casing a, seal grout b
The filling process, the sleeve pipe (outer pipe) c installation process, the casing a drawing process, the cracking and water pressing process and the grout injection process are shown. For cracking, water pressing and grout injection, the injection pipe (inner pipe)
d applies.

In the case of applying the sleeve injection method to improve the ground, the sleeve pipe is removed from the boring process.
The following problems were pointed out during the installation process
There is . (B) When performing under pressured water, in the boring process
The existing casing pipe mouth when adding the casing.
Spring is more likely to gush out and be dangerous. (B) Appropriate centering means when installing the sleeve pipe
It is not convenient.

The present invention can eliminate the above-mentioned problems by three
The purpose is to provide a bupipe installation device.
It was the one.

[0006]

SUMMARY OF THE INVENTION The present invention is a sleeve
The sleeve pipe applied to the construction method is built in the ground to be improved.
It is a device for digging in the casing for the ground to be improved.
Casing, and the rear part of the casing
It is inserted and removed at the insertion part and is integrally rotatable so that it can be rotated.
Tip bit and the tip in a state of being loosely inserted in the casing
The part can be inserted and connected in the insertion part at the rear of the tip bit.
Equipped with a leave pipe, the tip bit is open at the tip
An injection port with a check valve is provided to connect the casing and the tip bit.
In between, the casing is usually in the
State, and if necessary, the tip of the sleeve pipe tip
With the insertion and connection to the bit as the key, remove the casing from the above.
It is equipped with a stopper mechanism that can be released from the stop.
On the inner circumference of the front of the casing, slide it on the sleeve pipe.
A sleeve pipe erection device, characterized in that a movable seal ring is provided .

[0007]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, the erection device of the present invention comprises a casing 1, and a tip bit 2 and a casing pipe 3 which are removably inserted at the tip of the casing 1.

The tip bit 2 has a hollow tubular insertion portion 21 on the base end side, and the insertion portion 21 has an outer diameter which can be inserted into the tip portion of the casing 1 in a substantially sliding manner.

In order to fix the casing 1 to the tip bit 2 in the inserted state, as shown schematically in FIG. 4, a locking projection 22 is provided on the outer peripheral surface of the insertion portion 21 of the bit 2.
However, on the inner peripheral surface of the front end of the casing 1, locking grooves 12 that are engaged with and disengaged from the locking projections 22 in the axial direction are formed at two positions at intervals of, for example, 180 °.

As shown in FIG. 1, the tip bit 2 has an injection port 23 (not shown in FIG. 4) for ejecting the drilling water supplied through the casing 1 toward the ground. Check valve 24 for preventing backflow of pressurized water
Are provided together with the holding spring 25.

Between the casing 1 and the tip bit 2,
Normally, a stopper mechanism 4 is provided which holds the casing 1 in a state where it is prevented from coming off from the tip bit 2 and releases the state from the state where it is retained by using the insertion of the sleeve pipe 3 in the casing 1 as a key when necessary.

The stopper mechanism 4 includes a ball 42 inserted into and retractable from a hole 41 provided in the insertion portion 21 of the tip bit 2, and a cylinder inserted into the insertion portion 21 so as to be movable in the axial direction. 43 as a component, the cylinder 43 is configured so as to selectively take a closed position that coincides with the hole 41 and an open position that is displaced to the tip side from the hole 41. It is held in the closed position by the restriction stopper 45.

As shown in FIG. 1, when the cylinder 43 is in the closed position, the cylinder 43 receives the lower end of the ball 42, so that the ball 42 projects outward and the inner peripheral surface of the tip portion of the casing 1 is covered. The casing 1 is locked in the hemispherical recess 46 to prevent the casing 1 from coming off.

On the other hand, as shown in FIG. 2, the sleeve pipe 3 is inserted and installed in the casing 1, and by this insertion and installation, the cylinder 43 is pushed through the tip of the pipe 3 against the holding spring 44 to the open position toward the tip. Then, the ball 42 is released from being received by the tube 43, and can be retracted into the hole 41. Therefore, the casing 1 is released from the retaining state, and the tip bit 2 is released.
It becomes possible to disconnect from.

In the open position of the tube 43, it is necessary to form a peripheral gap 47 between the tip of the sleeve pipe 3 and the insertion portion 21 so as to allow the ball 42 to be retracted into the hole 41. For this purpose, the tip 31 of the sleeve pipe 3 is
Has a diameter smaller than the inner diameter of the insertion portion 21.

When the sleeve pipe 3 is inserted and installed, the pipe 3 tends to be pushed out of the casing pipe 1 by the spring force of the holding spring 44. In order to counter this pushing tendency, a threaded portion 32 is formed on the outer peripheral surface of the portion of the sleeve pipe 3 subsequent to the tip small diameter portion 31, and the threaded portion 32 is formed on the inner peripheral surface of the base end portion of the insertion portion 21. Contact it is configured such that screwed to the screw portion 23 formed on the
Ri, ahead of the sleeve pipe 3 at threaded connection to the front end bit 2
Firmly insert the end into the insertion part 21 of the tip bit 2.
Can be combined.

FIG. 1 shows a situation at the time of forming a hole. A tip bit 2 is inserted into the tip of a casing 1, and a stopper mechanism 4 holds the casing 1 against the tip bit 2. In the state shown in FIG. 1, by rotating the casing 1 while supplying drilling water, the tip bit 2
In addition, the drilling guide with the drilling water ejected from the injection hole 23 of the bit 2 can form a drilling hole having a predetermined depth in the ground to be improved. During drilling work, the slime produced is
Both of them guide the outside of the casing to the mouth part while backflowing . Although the sleeve pipe 3 is shown in FIG. 1 for convenience,
During the drilling work, the sleeve pipe 3 does not exist in the casing 1.

The drilling work on the ground to be improved is carried out by replenishing the casing 1 until a predetermined depth is reached. However, since the injection port 23 of the tip bit 2 is provided with a check valve 24, it is temporarily pressed. Even in the case of construction under water, there is no fear that the water under pressure will flow back into the casing 1 through the nozzle 23, and the work of adding the casing 1 can be safely performed without the danger of spring water.

Further, since the drilling work is performed in a state where the casing 1 is fixed to the tip bit 2 via the stopper mechanism 4, the rotation of the casing 1 may be interrupted when the casing 1 is added or when the casing 1 is rotated backward. However, there is no risk that natural cutting will occur between the casing 1 and the tip bit 2, and the drilling operation can be performed safely and reliably regardless of the structure in which the tip bit 2 can be cut when necessary.

[0021] After completion of the boring work by the casing 1, further tip sleeve pipe 3 is installed into the casing 1, as shown in FIG. 2 is a front end bit 2 plug
It is inserted and coupled in the portion 21. The stopper mechanism 4 serves as the casing 1 with the insertion and connection of the sleeve pipe 3 as a key.
Is released from the retaining state, so that the casing 1 is ready to be separated from the tip bit 2, and by pulling out the casing 1 in the state shown in FIG. 2, the sleeve pipe 3 is moved to the insertion setting position. , Can be left with the tip bit 2. Insert and connect to the insertion part 21 of the tip bit 2
The sleeve pipe 3 is located at the center of the hole,
Centering is done automatically.

A seal ring 11 is attached to the inner peripheral surface of the front portion of the casing 1 in order to prevent spring water from coming out of the casing 1 when the casing 1 is pulled out. As the casing 1 is pulled out, the sealing 11 slides on the sleeve pipe 3 to close the gap between the casing 1 and the pipe 3.

After the casing 1 is pulled out to the vicinity of the mouth, the sleeve pipe 3 inserted and installed and the pipe 3
Utilizing an injection pipe (see FIG. 5) inserted therein, the ground is improved by injecting grout through a seal grout filling step into the drilled hole, a cracking step and a water pressing step.

[0024]

[Effects] According to the erection device of the present invention, since the check valve is provided at the injection port of the tip bit, the measure for preventing the spring water from the casing is perfect, and the seal provided in the casing 1 is also effective.
When pulling out the casing 1 with the reel ring 11,
The measures to prevent spring water from flowing are perfect, and the sleeve pipe 3
Construction can be done safely even under pressured water.

Further, although the casing is constructed so that it can be separated from the tip bit when necessary, since the casing is normally retained by the stopper mechanism by the action of the stopper mechanism, the casing is inadvertently separated during drilling work. There is no risk that it will occur, and work can be performed safely.

Further, the tip portion of the sleeve pipe is a tip bit.
Since it is inserted and connected in the insertion part of
Automatic centering of sleeve pipe in drilling hole
It will be carried out automatically, and it is possible to save the trouble of centering
It

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a diagram corresponding to FIG. 1 showing a situation when a sleeve pipe is inserted and installed.

FIG. 3 is a view corresponding to FIG. 1 showing a situation of pulling out a casing.

FIG. 4 is a partial detailed view showing a connection structure between a casing and a tip bit.

FIG. 5 is an explanatory diagram showing an example of a conventional ground improvement method.

[Explanation of symbols]

 1 Casing 2 Tip bit 3 Sleeve pipe 4 Stopper mechanism

Claims (1)

[Claims] 1. A sleeve applied to a sleeve injection method.
A device for building a pipe in the ground to be improved,
Casing for digging casing for improved ground,
Can be inserted into and removed from the front end of the
Tip bit and casein which are integrally rotatably inserted and joined
Insert the tip into the rear part of the tip bit while loosely inserting
Equipped with a sleeve pipe that can be inserted and joined in the only part
The bit is equipped with a check valve with a check valve that opens at the tip.
A casing is usually installed between the housing and the tip bit.
Hold the tip bit in a retaining state and slide it when necessary.
The key is to insert and connect the tip of the pipe to the tip bit.
Then, the stopper that can release the casing from the above retaining
-A mechanism is provided, and further on the inner circumference of the front part of the casing
Features a seal ring that can slide on the sleeve pipe
The device for installing a sleeve pipe, which is characterized in that