JPS5933757B2 - Method for expanding small diameter holes using muddy water - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for enlarging a curved or horizontal small diameter hole provided underground while carrying out excavated soil using muddy water.

Conventionally, in the method of enlarging a curved or horizontal small diameter hole provided underground, as shown in Figs. 16 and the gap between the preceding curved small diameter hole 1 and the preceding drill pipe 2.

However, in the case of the conventional method, since muddy water containing excavated soil flows between the excavated hole and the pipe, there is a fear that the excavated soil may remain or the enlarged hole may become enlarged due to scouring.

Therefore, as a method for solving the above-mentioned problem, the present inventors
As shown in FIG. 3, an excavated soil recovery hole 3 for recovering excavated soil is provided in the hole expansion bit 5, and the amount of muddy water is adjusted by a muddy water volume adjustment device 4 in the drilling mud water spout hole 9 and the preceding drill pipe 2. Dividing the flow, drilling using the muddy water coming out of the drilling muddy water spouting hole 9, mixing the muddy water passing through the muddy water flow hole 10 in the drill pipe with the excavated soil collected from the excavated soil recovery hole 3, and flowing it. We proposed a method in which hole expansion is carried out over the entire section while draining muddy water mixed with the drilling crew to the ground ahead.

However, in this method, muddy water is pumped from the rear ground and discharged to the front ground until completion of the hole expansion excavation of the entire section, which significantly increases the amount of muddy water used.

For this reason, there are problems in that the cost of drilling for hole expansion becomes high, muddy water equipment such as a muddy water tank becomes large-sized, and a large space is required for installing the muddy water equipment.

It is an object of the present invention to provide a method for expanding curved or horizontal small diameter holes using muddy water, which advantageously solves the above-mentioned problems.

Next, the present invention will be explained in detail using illustrated examples.

First, as shown in Fig. 1, a curved or horizontal small-diameter hole 1 in the form of an arc with both ends open to the ground surface is prepared by a conventional method, and the hole 1 is completely inserted into the curved or horizontal small-diameter hole 1. A front solid shaft portion of a hole expansion bit 5 is connected to the rear end of the preceding drill pipe 2 (the connection portion is not shown), and the hole expansion bit 5 is connected to an excavated soil recovery hole 3. ,
Mud water amount adjustment device 4 consisting of a control valve, mud water spout hole 9 for drilling
A mud water outflow hole 10 in the drill pipe is provided, and the front end of a subsequent drill vibro made of a steel pipe having approximately the same rigidity as the preceding drill pipe 2 is attached to the rear solid shaft portion of the hole expanding bit 5. The rear end of the subsequent drill vibro is gripped by the rotary propulsion device 7 and propelled while being rotated.

As shown in FIG. 5, the flow of mud during propulsion is carried out through the drill pipe, which has a mud water spout hole 9 for drilling and a mud water volume adjustment device 4, which is provided in the bit. The muddy water that flows into the muddy water spouting hole 9 is spouted out to the front of the excavation surface and mixed with the excavated soil, and the muddy mixed excavated soil is collected from the excavated soil recovery hole 3 and sent to the drill. The mud flows in the preceding drill pipe 2 along with the mud flow divided into the in-pipe mud water outflow hole 10 and is discharged to the ground surface in front.

In this way, after drilling a hole for a certain length, the drilling is stopped, and for the next drilling, mud is pumped from the ground ahead into the drill pipe 2 and the mud water amount adjustment device 4. , the flow is reversed through the subsequent drill vibro (see Figure 6), and is directed to the rear ground, and then the above-mentioned hole expansion drilling and muddy water cleaning work are repeated alternately as many times as necessary to complete the entire section. Expansion drilling will be carried out over the entire area.

Note that when the hole expansion ratio is small with respect to the small diameter hole 1, the sheath tube support member 12, the bearing 13, the thrust bearing 14, the support flange 15, and the sheath tube 16 may be omitted.

Further, in the figure, 11 is a bit for drilling small diameter holes, and 17 is a sheath pipe joint.

According to this invention, the hole-expanding bit 5 is provided with the excavated soil recovery hole 3 and the muddy water amount adjusting device 4 at the rear end of the preceding drill pipe 2 inserted into the curved or horizontal small-diameter hole 1. In the drilling method for a small diameter hole in which the hole expanding bit 5 is rotatably propelled by a rotary propulsion device 7 via a subsequent drill vibro, muddy water is sent from the rear end of the drill vibro on the ground and the drilling The soil is recovered through the excavated soil recovery hole 3 provided in the hole expansion bit 5, and flows inside the preceding drill pipe 2 in the curved or horizontal small diameter hole 1 with the flow rate adjusted by the muddy water regulating device 4. The muddy water is used to transport the excavated soil to the ground in front of the ground, and then the drilling is carried out, and then the drilling is stopped and the muddy water on the ground in front is transferred to the advance drill pipe 2 and the muddy water amount adjustment device for the next drilling. 4
, the flow inside the subsequent drill vibro is reversed and the air is flown backward to the ground.
Next, the holes are expanded over the entire section by repeating the above-mentioned hole expansion drilling and muddy water treatment alternately, so it is possible to drill long distances by repeatedly using a small amount of muddy water. It is possible to perform long-distance drilling using muddy water at low cost, and the muddy water equipment such as a muddy water tank can be made small, and the installation space for the muddy water equipment can also be small.

[Brief explanation of drawings]

Figure 1 is a longitudinal side view showing the state in which a curved small diameter hole is drilled;
Fig. 2 is a longitudinal side view showing a curved small-diameter hole being enlarged, Fig. 3 is a partially cutaway schematic longitudinal side view near the bit portion, Fig. 4 is a front view showing the front side of the bit, and Fig. 5 is FIG. 6 is a partially cutaway schematic vertical side view showing the flow of muddy water during excavation, and FIG. 6 is a partially cutaway schematic longitudinal side view showing the flow of muddy water when the muddy water is sent back. In the figure, 1 is a small diameter hole, 2 is a leading drill pipe, 3 is an excavated soil recovery hole, 4 is a mud water volume adjustment device, 5 is a hole expansion bit, 6 is a trailing drill pipe, 7 is a rotary propulsion device, and 9 is a drilling device. 10 is a mud water flow hole in the drill pipe, 12
1 is a sheath tube support member, 13 is a bearing, 14 is a thrust bearing, 1
6 is a sheath pipe, and 17 is a sheath pipe joint.

Claims (1)

[Claims] 1 Attach a hole expansion bit 5 equipped with an excavated soil recovery hole 3 and a muddy water volume adjustment device 4 to the rear end of the preceding drill pipe 2 inserted into a curved or horizontal small diameter hole 1,
In a method for expanding a small diameter hole in which the hole expanding bit 5 is rotationally propelled by a rotary propulsion device 7 via a subsequent drill vibro, the muddy water and excavated soil introduced from the rear end of the drill vibro on the ground are expanded. The excavated soil is collected through the hole 3 provided in the hole bit 5, and then collected through the curved or horizontal small diameter hole 1.
The muddy water flowing inside the preceding drill pipe 2 with the flow rate adjusted by the muddy water regulating device 4 is used to transport the excavated soil to the ground in front of the ground before drilling the hole, then stopping the drilling and drilling the next hole. For the hole expansion drilling, muddy water on the ground in front is made to flow backward through the preceding drill pipe 2, the muddy water volume adjustment device 4, and the following drill vibro, and is discharged to the rear ground. A method for enlarging a small diameter hole using muddy water, which is characterized by repeating the steps alternately and enlarging the hole over the entire section.