JPS5925073B2 - Spring water seepage prevention device in excavation - Google Patents

Description

[Detailed Description of the Invention] In wireline core collection polling, this invention sends pressurized water into the drill pipe, guides it into the drilled hole from the tip of the drill bit, and guides it to the outside through the mouth guide pipe. This invention relates to a spring water seepage prevention device for excavation using a positive circulation method.

In this type of drilling, especially in horizontal drilling, there is a risk that the hole will collapse due to seepage of spring water.

For this reason, the water pressure within the borehole must be maintained at a predetermined value to prevent seepage of spring water, not only during excavation but also during connection of the drill pipe.

This invention aims to provide an improved spring water seepage prevention device for excavation by structurally improving the water supply channel in excavation and maintaining the internal pressure of the borehole at a predetermined value even when connecting a drill pipe. It is something.

Another object of the present invention is to provide a device for preventing seepage of spring water in a drilling hole, which is improved so that the pressure inside the hole can be maintained at a predetermined value even when an inner tube is taken out in a coring.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings regarding a positive circulation horizontal drilling apparatus for core collection polling using a wireline method.

In the figure, reference numeral 1 denotes a drilling machine, through which a drill pipe blonde 2 is inserted, and is fed into a drilled hole by an appropriate means.

The drill pipe 2 includes an outer tube 4 with a drill bit 3 attached to its tip, and a bottomed inner tube 5 disposed within the outer tube 4.
The distal end of the inner tube 5 is open to the drill bit 3, and the proximal end is connected to a block 7 having a water channel 6.

The block 7 is equipped with a ball type check valve 8 made of a ball and a spring, and also has a spare head 9.
is provided at the proximal end.

A wire 11 is connected to an overshot 10 that removably engages with the spare head 9.
is the water swivel 12 via the drill pipe 2,
Via the stop valve 13 and guide valve 14,
The wire hoist 1 is led out to the outside and connected to the wire hoist 1 via a pulley 15.
6 is involved.

A mouth guide pipe 17 is installed at the mouth of the borehole, and the pipe 17 communicates with a branch 19 via a mouth stop valve 18, and a preventer 2 is connected to the branch 19.
By connecting 0, the gap between the drill pipe 2 and the mouth guide pipe 17 passing through the inside thereof is kept liquid-tight.

A water channel 21 from the branch 19 is communicated with a pressure regulating valve 22 and, via this, with a drainage channel 23.

In addition, the base end K of the guide pipe 14 (d side nipple 2
4 is provided, and the side nipple 24 is connected to a discharge port of a pump 26 via a hose 25.

The suction port of the pump 26 is connected to the suction tank 2.
7, and water is supplied to the suction tank 2γ.

In addition, in the figure, numerals 28, 29, and 30 are stop valves.

In such a configuration, the spare head 9 is normally locked in the outer tube 4, and is reliably held against the drill drop 2 against reverse water pressure during the digging process.

Therefore, pressure water introduced into the drill pipe 14 via the side nipple 24 by the action of the pump 26 is guided into the drill pipe 2 via the stop valve 13 and the water swivel 12.

Then, the pressure water led out into the drill bit 3 horizontal hole through the check valve 8 returns to the branch 19 through the mouth guide pipe 17 together with the slime, and is brought to the pressure regulating valve 22 through the water channel 21. .

When the pressure of this pressurized water exceeds a predetermined value, the valve 22 is opened, and when it falls below a predetermined value, the valve 22 is closed.

On the other hand, the cored core is stored in the inner tube 5.

In this state, there is no backflow of pressure water due to the action of the check valve 8, so even if you connect the drill rod 2, for example,
The water pressure inside the borehole does not decrease, and spring water seeps out.
This is prevented by the pressure inside the borehole, and wall collapse is therefore avoided.

In addition, in order to collect the core inside the inner tube 5, first, the overshot 1 is passed through the guide pipe 14.
0 is inserted and advanced into the drill pipe 2 via the water swivel 12 by water pressure, collides with the spare head 9, and releases the engagement with the drill pipe 2.

By unwinding the wire 11 in this state, the overshot 10, block 7, and inner tube 5 are returned.

On the other hand, since the pressurized water is continuously sent into the borehole through the check valve 8, the inside of the borehole is maintained constant despite the retreat of the inner tube 5.

In this state, the inner tube 5 is pulled back to the position of the guide pipe 14 and the stop valve 13 is closed.

As a result, the area after the water swivel 12 is sealed, so that the inside of the drill pipe 2 and the inside of the drill hole are maintained at a predetermined water pressure.

In this state, the inner tube 5 is removed from the guide pipe 14 and the core is collected.

To return the inner tube 5, reverse the above procedure, insert the inner tube 5, apply water pressure, and press the stop valve 13.
Open it and return the inner tube 5 (along with the block γ and spare head 9) into the drill pipe 2.

In this way, even when the inner tube 5 is removed from the drill pipe 2, the pressure of the pressurized water in the drilled hole can be maintained at a predetermined value.

For this reason, wall collapse due to seepage of spring water is avoided.

As described in detail above, this invention utilizes a wireline method in a positive circulation method in which pressurized water is sent into a drill pipe, guided into a drilled hole from the tip of a drill bit, and then led out to the outside via a mouth guide pipe. During core collection polling, a pressure adjustment valve is installed in the outlet path that communicates with the mouth guide pipe, so this works in conjunction with the conventional structure in which a check valve is installed in the inner tube for coring inside the outer tube of the drill pipe. By maintaining the internal water pressure in the borehole above a predetermined value, it is possible to prevent seepage of spring water and avoid wall collapse.Especially in collapsed spring water layers, it is possible to prevent wall collapse of the borehole. It has a great preventive effect.

The inner tube for coring that opens at the tip of the drill bit is removably equipped inside the drill pipe, and the overshot that is taken out with the check valve of the inner tube is installed with a water swivel against the drill nozzle. By providing a stopper valve between the guide pipe and the water swivel that communicate with each other, the internal pressure within the borehole can be maintained even when the inner tube is taken out and the core is collected.

[Brief explanation of drawings]

FIG. 1 is a schematic system diagram showing one embodiment of the present invention, and FIG. 2 (A) and (C) are partially longitudinal side views. 1...Testing machine, 2...Drill pipe rod, 3...Drill bit, 4...Outer tube, 5...Inner tube ,6
...Waterway, 7...Block, 8...
...Check valve, 9...Shair head, 10...
...Overshot, 11...Wire,
12...Water swivel, 13...
Stop knob lubricant, 14...Guide pipe, 1
5... Pulley, 16... Wire hoist, 17... Mouth guide, 18...
... Mouth stop valve, 19 ... Turnout, 2
0... Preventer, 21... Waterway,
22...10. Pressure adjustment valve, 23...Drain channel, 24...Side nipple, 25...
...Hose, 26...Pump, 27...
・Tank, 28, 29, 30...stop valve.

Claims (1)

[Claims] 1. A check valve is provided in the inner tube for coring in the outer tube of the drill pipe to maintain the internal water pressure in the drilling hole at a predetermined value or higher, and the core ring opens to the tip of the drill bit. In a wireline core collection polling device with a positive circulation system, the inner tube is removably installed inside the drill pipe and the inner tube is taken out with a check valve by an overshot. A drill pipe is inserted through the drill pipe, a pressure regulating valve is provided in a waterway that branches between the guide pipe and the preventer, and an inner tube taken out by the overshot is communicated with the drill pipe via a water swivel. 1. A device for preventing seepage of spring water in excavation, characterized in that the spring water can be introduced through a guide pipe, and a stop valve is provided between the guide pipe and the water swivel.