JPH0314991B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" This invention relates to a capsule for transporting a drug solution in a borehole.

"Conventional Technology" For example, in oil, geothermal and metal exploration, drilling wells are drilled.

However, since the well is at least 500 to 5,000 meters deep, water is lost during drilling.

When this happens, the circulating mud for drilling in the borehole escapes into the ground from the hole wall, making it impossible to maintain the head of the mud and causing the hole wall to collapse.

Therefore, a chemical solution having the effect of filling the water gap is supplied to this water loss location.

Conventionally, the method of supplying this fluid was through pipes that transported the chemical solution after the muddy water that preceded it, creating a so-called multiphase fluid. Due to problems with the rod's durability and the excessive time it takes to raise and lower the rod, a method of introducing capsules filled with a medicinal solution has recently been adopted.

The means for dispersing the drug solution from the capsule that has reached the hole bottom includes a method of destroying the entire capsule, or a method of destroying a part of the capsule by colliding a destruction weight against an easily breakable wall to form an injection hole. A method has been proposed in which a valve attached to the tip is opened by sending a messenger from the ground.

``Problem to be solved by the invention'' However, the above-mentioned method of destroying the whole system requires a destruction mechanism (bursting device for explosives, etc.) that must be handled with care, and some rupturing devices have holes. There is a risk of destroying the wall, and furthermore, it is necessary to provide a destruction mechanism within the capsule, which complicates the mechanism and reduces the amount of medicinal liquid sealed within the capsule. In addition, in the case of the method using a breaking weight, use a wire to prevent the attached breaking weight from falling off while the capsule is descending (the breaking weight may damage the drilling blade of the excavator if it remains in the hole after the impact breaking action). , which must be recovered) may become entangled, or the weight of the suspension may move within the drug solution due to factors such as the buoyancy of the drug solution inside the capsule, making it impossible to reliably destroy and inject at a predetermined depth. Furthermore, in the case of a method that opens a valve attached to the tip,
The valve may not open reliably due to water pressure in the hole, muddy water, excavation slime, etc.

"Means for Solving the Problems" and "Operation" The present invention was made in view of the above circumstances, and its gist is that the entire capsule or steel pipe or heat-resistant FRP designed as a mere container is
Assuming that the bottom plate, which is fitted into the cylinder body made of resin or the like, is made of a resin material made of thermoplastic material designed to soften to the point where the chemical solution diffuses at a predetermined depth, the conventional method described above is used. This method completely eliminates the problems associated with chemical liquid diffusion means.

"Example" This will be explained in detail below based on the drawings.

FIG. 1 is an overhead view of the entire capsule made of thermoplastic resin, and FIGS. 2 a and 2 b are vertical cross-sectional and developed views of the capsule bottom plate made of thermoplastic resin. In Figure 1, 1 is a capsule designed simply as a container for chemical solutions, and the entire capsule is made of vinyl chloride resin, vinyl acetate resin, acrylic resin, styrene resin, polyethylene, cellulose plastic, etc., which becomes plastic when heated. Manufactured with

The selection of the resin material and the design of its thickness etc. are based on the temperature at the depth in the borehole where water loss occurs, the selection of a resin whose softening temperature is at that temperature, the time required for descent, the softening (melting) time, etc. It is determined by comprehensively considering various factors. For example, the softening (dissolution) temperature of a thermoplastic resin in muddy water is approximately as follows.

Vinyl chloride resin (soft) 40 to 60°C (hard) 60 to 80°C Vinyl acetate resin 50 to 100°C Acrylic resin 80 to 150°C Also, the softening (dissolution) time is about 10 to 30 minutes. Furthermore, the temperature distribution in the borehole 2 is as shown in FIG.

In FIG. 1, 1a is a chemical solution inlet provided in the canopy, and 1b is a stop for hanging the wire 3.

Furthermore, it is preferable that the tip of the capsule be tapered as shown in the figure. This is because drilling hole 2 is, in addition to the above points, very few boreholes are vertical, and in some places the drilling angle is 30 degrees or 45 degrees, and the hole wall surface is smooth. It has a rough surface with irregularities rather than a surface, and therefore, in order to ensure a smooth descent of the capsule, the capsule itself must have a guiding ability.

In Figure 2, numeral 4 is the capsule cylinder body designed as a mere container, which is made of steel pipe or heat-resistant material.
Manufactured from FRP resin, etc.

4a is a chemical solution inlet provided in the canopy, and 4b is a stop for hanging the wire 3. The cylinder body 4 is intended to be recovered. Reference numeral 5 denotes a bottom plate portion which is fitted into the cylinder body 4, and in the illustrated example, it is provided with a screw fitting assembly formed by threaded portions 4c and 5a.

The bottom plate part 5 is made of the same material as the capsule 1 described above, and in this case, the design determining factors include not only the softening (dissolution) of the bottom plate part but also consideration of the possibility of disengagement of the fitting part. It will be done.

As naturally expected from the above explanation, in the present invention, the contained chemical solution is diffused by softening (dissolving) the thermoplastic resin. Figure 4 a, b Figure 5 a-c
Now, the procedure for dispersing the chemical solution in the present invention will be explained. In Figure 4 showing the use of the one in Figure 1,
The capsule 1 that has descended into the muddy water area (Figure a) is softened (dissolved), and the crack 6 is sealed by the diffusion of the chemical solution, and the wire 3 is pulled up (Figure b).

Next, Figures 5 a-c show the use of those in Figure 2.
The capsule that descended into the muddy area was (a
), the bottom plate part 5 softens (dissolves) and diffuses the chemical solution,
Seal the crack 6 (Figure b). Pull up the cylinder body 4 (Figure c).

"Effects of the Invention" The effects of the present invention described above are listed below.

(1) The chemical solution can be reliably diffused and water can be stopped at a specified location.

(2) The softened (dissolved) capsule becomes a sealant for cracks.

(3) There is no need for a mechanism to destroy the capsule.

(4) The capsule is simple and easy to work with.

(5) Water can be stopped at any point, such as in the middle of the hole wall.

(6) Low cost. In particular, the bottom plate dissolving type can be used repeatedly, and the bottom plate is also inexpensive, making it very inexpensive.

(7) The type that dissolves the entire capsule has good workability because it is possible to descend one capsule and then the next capsule in sequence, and is particularly advantageous in cases of large water leaks.

[Brief explanation of the drawing]

Figure 1 is an overhead view of the entire capsule of the present invention made of thermoplastic resin, Figures 2 a and b are longitudinal sections of the capsule bottom plate made of thermoplastic resin,
FIG. 3 is a diagram showing the temperature distribution in the borehole, and FIGS. DESCRIPTION OF SYMBOLS 1...Capsule, 2...Drilling hole, 3...Wire, 4...Cylinder body, 5...Bottom plate part, 6...Crack part.

Claims (1)

[Claims] 1. The entire capsule designed as a simple container or the bottom plate part that is designed to fit into the cylinder body made of steel pipe or heat-resistant FRP resin, etc., is designed to soften to the point where the chemical solution spreads at a predetermined depth. A capsule for transporting a chemical solution in a borehole, characterized in that it is made of a resin material made of a thermoplastic substance.