JPH0617040Y2 - Mud drilling method mud sending device - Google Patents

Description

[Detailed description of the device] << Industrial application field >> This device relates to a mud sending device used in a mud drilling method.
In particular, the present invention relates to a mud sending device suitable for gelled mud having high viscosity.

<Prior art> As is well known, in construction works in the field of urban civil engineering, underground walls, tank peripheral walls, foundation piles, etc. are constructed by the mud drilling method.

In this method, clay such as bentonite is suspended in water, mud is added by adding a dispersant, thickener, etc., and the ground is excavated in a groove or circular shape to fill it with a predetermined depth. After excavating to muddy water, the mud water inside is replaced and the concrete is hardened to build walls and piles underground. However, for example, when the water permeability is large like the gravel ground along the riverbed, muddy water excessively permeates and flows into the surrounding ground, and it becomes difficult to constantly fill the digging pit with muddy water.

Therefore, the present applicant has previously dissolved guar gum and its modified products, or plant mucilages such as roasted bin gum, alone or in combination, and dissolved in water, and then added an additive such as borax or boric acid to form a gel. It was developed as muddy water. This gelled mud has a viscosity of tens of thousands of CP to tens of CP depending on the pH.
Varies over an extremely wide range.

Therefore, by using this type of gelled muddy water, sufficient permeation-preventing hardening can be obtained even in a water-permeable ground.

<< Problems to be solved by the invention >> However, this gelled mud has a problem that it is difficult to send mud due to its high viscosity and soft substance.

In other words, it is sufficient if there is a space for mixing and supplying near the site of the drill hole, but if it is difficult to obtain a site for the mud making plant near the site of the drill hole, the construction site and the gelled mud storage tank The distance between and is quite large, which makes mud sending work difficult.

This invention solves the above-mentioned problems, and an object thereof is to enable good mud sending even when the mud sending distance of this type of gelled mud is long.

<< Means for Solving Problems >> In order to achieve the above object, the present invention is directed to a mud feed pipe provided between an excavation hole and a liquid tank, and a suction pump installed at one end of the mud feed pipe. And a viscosity of 10,000 to 15,000 cp gelled mud is sucked by the pump and discharged from one of the mud pipe to the other mud drilling method for mud drilling method, the mud pipe, A plurality of air injectors, which are inclined toward the mud-sending direction and have injection ports provided at the center of the mud-sending tube, are projected through the air-suction end at predetermined intervals, and each of these air injectors is a pneumatic feed end of the compressor. It is connected to.

<< Operation >> The compressed air sent from the compressor is pressed into the mud pipe by the air injector, and becomes a bubble of the pressurized air to convey the highly viscous gelled mud in the direction of the pump.

<< Embodiment >> An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an explanatory view of a mud sending device showing a case where the present invention is applied at the time of mud recovery in a mud excavating direction.

In the figure, a mud feed pipe 3 is arranged between the excavation hole 1 and the recovery liquid tank 2 for the gelled mud water G. In the drill hole 1, a submersible sand pump 4 connected to the suction end of the mud pipe.
Has been inserted. A connecting pipe 5 is arranged at an appropriate interval in the middle of the mud sending pipe 3.

The connecting pipe 5 has a sectional shape shown in FIG.

In the figure, the connection pipe 5 is open at both ends, this portion is connected to the mud feed pipe 3, and an air injector 11 is provided so as to penetrate through the pipe wall of the connection pipe 5.

The air injector 11 has an injection port provided at the center of the connecting pipe 5 and is inclined toward the mud feeding direction.

Each injector 11 of the connecting pipe 5 is connected to the pneumatic feed end of the compressor 8 via a high pressure hose 9.

In the above configuration, the tremie pipe (not shown) is provided with the drill hole 1
When the concrete is poured into and the concrete is poured, the liquid level of the gelled mud G filled in the excavation hole 1 rises. At this time, the submersible sand pump 4 of the mud sending device is driven and the compressor 8 is driven.

If the submersible sand pump 4 alone is used, it becomes very difficult to send mud when the distance between the drill hole 1 and the liquid tank 2 is long, and the gelled mud pumped by the pump 4 is stored in the mud pipe 3 Adhered to and solidified into a gel in a state of being filled inside, and finally mud cannot be sent only by the pumping force of the pump 4.

However, at this time, by driving the compressor 8 at the same time as the pump 4, the pressurized air is blown through the injector 11 in the same direction as the gelled mud pressure feeding direction as indicated by the arrow in FIG. Correspondingly, the gelled muddy water G is pressed, and while being mixed with gas and liquid, it is pressure-fed to the next pipe position of the connecting pipe 5. Although the pressure-fed energy by such pressure air is gradually reduced, the pressure-air blown out from the injector 11 in the next section sequentially performs the pressure-feeding operation, and finally is sent to the liquid tank 2 and recovered. It will be.

The submersible sand pumps 4 to 5 were actually used.
The first connecting pipe is placed at a distance of m, then the second connecting pipe is placed at a position 30 m away from the first connecting pipe, and the mud is sent at a position within 30 m of the second connecting pipe. The tube was connected to the collection tank. The viscosity of the gelled mud in the drill hole 1 is 10,0.
00 ~ 15,000CP, the air pressure of the compressor 8 is 7
It was kg / cm ² .

Under the above conditions, the submersible sand pump and compressor were driven simultaneously, and when the mud water was pumped through the mud pipe, it was confirmed that the mud feeding work could be performed more smoothly than when using the submersible sand pump alone. confirmed.

In addition, the arrangement interval of the injectors should be set according to the gelling viscosity, and when the viscosity is high compared to the construction example, the interval can be shortened, and when the viscosity is low, it can be dealt with and the experiment can be performed. By repeating the process, it is possible to easily determine the relationship between the installation intervals according to the viscosity.

Further, as a pneumatic feeding method of the compressor 8, it is possible to intermittently feed the air instead of continuously.

Further, although the muddy water has been described in the embodiment, it can be applied to the case of sending mud from the liquid tank into the excavation hole 1 contrary to the above. In this case, the air pressure sending direction of the air injector 11 can be reversed. It will be good.

<< Effects of the Invention >> As described in detail with reference to the embodiments above, according to the mud drilling method mud sending device of the present invention, the compressed air pressure-fed from the air compressor is used as auxiliary power, so that the conventional pump is used. Compared with the case where gelled mud is pumped by a single unit, the driving power of the pump can be small, the pipe diameter of the mud feed pipe can also be made small, and further an injector can be provided according to the mud feed distance, Even if it is a long distance, it is possible to satisfactorily carry out the mud sending work with relatively small power.

Therefore, the present invention is particularly suitable for a mud excavation method using high viscosity gelled mud, and when the distance between the excavation site and the mud storage tank is large.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall explanatory view of a mud sending device showing a case where the present invention is applied during mud recovery of a mud drilling method, and FIG. 2 is a sectional view of a connecting pipe equipped with an air injector. . 1 ... Drilling hole, 2 ... Liquid tank 3 ... Mudging pipe, 5 ... Connection pipe 11 ... Air injector 8 ... Compressor, 9 ... High pressure rubber hose G ... Gelled mud water

Claims (1)

[Scope of utility model registration request] 1. A mud sending pipe provided between an excavation hole and a liquid tank, and a suction pump installed at one end of the mud sending pipe, wherein the gelled mud having a viscosity of 10,000 to 15,000 cp is provided. A mud sending device for sucking up with a pump and discharging from one side of the mud sending pipe to the other, wherein the mud sending pipe is inclined in the midway of the mud sending direction, and an injection port A plurality of air injectors provided at the center of the mud pipe are projected through at a predetermined interval, and each of these air injectors is connected to the pneumatic feed end of the compressor. apparatus.