JP2754194B2 - Hydraulic crusher packer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packer for performing hydraulic crushing using a well bore excavated in rock.

[0002]

In general, a packer for hydraulic crushing divides a predetermined section in a well bore excavated in a bedrock with a pair of rubber seals and applies water pressure to the partitioned section to forcibly crack. It is used to increase the permeability of the rock and to calculate the stress state in the rock from the water pressure at the time of crack formation. Only when the cracks formed are perpendicular to the axis of the well and the thickness of the target rock is sufficiently thin to allow drilling of a well that penetrates the rock, Hei 7-29701
No. 5), the amount of opening of a crack can be measured by the same method. However, in the case of hydraulic fracturing at the site, in general, the position at which the hydraulic fracturing is performed is extremely deep, and it is not possible to excavate a well that penetrates the target rock. Can not. Therefore, a method of indirectly estimating from the displacement of the rock on the rock surface had to be adopted. Also, even with this method, measurement was practically impossible when the hydraulic crushing position was very deep in the borehole.

[0003] The present invention has been made in view of the above-described background, and an object of the present invention is to generate a crack in rock in a relatively deep borehole that does not penetrate, and An object of the present invention is to provide a packer for hydraulic crushing that can directly measure the opening amount of a crusher.

[0004]

In order to achieve the above object, a packer for hydraulic crushing according to the present invention comprises a deeper packer unit integrated with a packer shaft and a hole-side packer unit sliding on the packer shaft. Each of the packer sections has a rubber seal that can be radially expanded by being compressed by fluid pressure, and a pressure water is applied between the packer pressure line for applying pressure to the deeper packer section and both packer sections. And a water injection line for injecting water is provided through the packer shaft, and a displacement meter for measuring a relative displacement amount of both packer portions is attached to the packer shaft.

[0005] The hydraulic crushing packer having the above structure is
A fluid injection section is formed between the two packers by applying a fluid pressure to both the packers at a predetermined position in the well and compressing and expanding the rubber seal in the radial direction to the hole wall. Then, when the rock is crushed by injecting the pressure water into the water injection section through the water injection line, the hole-side packer moves on the packer shaft in accordance with the opening displacement amount of the crack. From the relative movement of the two packers, the opening displacement amount of the crack at the time of crack formation by hydraulic fracturing can be measured.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing an example of a packer for hydraulic crushing according to the present invention. As shown in the figure,
The packer includes a deeper packer portion 2 integrated with the packer shaft 1 and a hole-side packer portion 3 that slides on the packer shaft 1. Each packer part 2,
3 has one or two compressible rubber seals 4, and when two rubber seals 4 are attached as shown in the figure, a metal ring 5 is attached between them. Also,
The packer shaft 1 has a deeper packer pressure line 6 for applying fluid pressure to the deeper packer portion 2 and a water injection line 7 for injecting pressurized water between the two packer portions 2 and 3. . In the figure, reference numeral 8 denotes a hole-side packer pressure line for applying fluid pressure to the hole-side packer portion 3. Further, a displacement meter 9 (for example, a differential displacement meter) for measuring a relative displacement amount of both the packers 2 and 3 is attached to the packer shaft 1 by a gripper 10.

After the packer is inserted into a well bore excavated in the bedrock, a pressure is applied by a fluid through a deeper packer pressure line 6 and a hole-side packer pressure line 8, whereby the rubber seals 4 of the packers 2 and 3 are formed. Are compressed and expanded in the radial direction, and the packer portions 2 and 3 are fixed to the hole walls, respectively. In this state, the pressurized water is injected into a water injection space partitioned by the rubber seal 4 through a water injection line 7 passing through the packer shaft 1. The water injection line 7 is connected to a pressure gauge 11 attached to the tip of the packer, and simultaneously measures the pressure. Thereafter, when the pressure of the injection water increases, a crack is formed in the bedrock in the section partitioned by the two packer parts 2 and 3. At this time, since the two packers 2 and 3 sandwiching the crack are independently fixed to the hole wall, the deeper packer 2 is leftward in the drawing, and the hole-side packer 3 is not fixed in the drawing. Now move to the right. By measuring the relative displacement of these two packer parts 2 and 3 with the displacement meter 9 attached to the packer shaft 1, the opening displacement of the crack can be known.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, FIGS. 2 and 3 are partial sectional views showing a packer according to the present invention. In these figures, 20 is the packer shaft, 30 is the deeper side packer part, and 40 is the hole side packer part. 21 is a deeper packer pressure line, and 22 is both packer parts 30 and 4.
A water injection line for injecting pressure water during 0, a cable line 23 connected to a pressure gauge 25 protected by a tip cap 24, and a hole-side packer pressure line 26. Reference numeral 27 denotes a displacement meter for measuring the relative displacement between the two packer units 30 and 40, which is attached to the packer shaft 20 by a gripper 28.

As shown in FIG. 2, two rubber seals 31 are provided around the packer shaft 20 and three metal rings 32 are sandwiched between the two rubber seals. A piston 33 and a casing 34 for guiding the piston 33 are disposed adjacent to the casing 33. The movement of the casing 34 is restricted by a tip cap 24 screwed to the tip of the packer shaft 20. A deeper packer pressure line 21 passing through the packer shaft 20 is formed between the piston 33 and the casing 34.
Open between. A coil spring 35 is inserted into the piston 33, and the rubber seal 31 and the metal ring 32 are constantly pressed by the coil spring 35.

As shown in FIG. 3, the hole side packer section 40 has a cylindrical member 41 slidable on the packer shaft 20 to the right, and two rubber seals 42 are provided around the cylindrical member 41. Two metal rings 43 are provided so as to sandwich them, and the flange portion 41a of the cylindrical member 41 is
Plays the role of the metal ring on the left (left). A piston 44 and a casing 45 for guiding the piston 44 are disposed adjacent to the right metal ring 43. The casing 45 is provided with a locking member 4 screwed to the right end of the cylindrical member 41.
6 restricts its movement. The hole side packer pressure line 26 penetrates the casing 45 and opens between the piston 44 and the casing 45. A coil spring 47 is inserted into the piston 44, and the rubber seal 42 and the metal ring 4 are
3 is always in a pressed state. The ring member 48 disposed on the left side of the flange portion 41a of the cylindrical member 41 is a kind of spacer for changing the length of the pressure water injection section, and is locked to the cylindrical member 41 by the pin 49. I have.

When the packer having the above configuration is inserted into the well and water is injected from the deeper packer pressure line 21, fluid pressure is applied between the casing 34 and the piston 33, and as a result, the piston 33 moves rightward in FIG. When the rubber seal 31 is pushed and moved, the rubber seal 31 is compressed via the metal ring 32 and expands in the radial direction, and the deep-side packer portion 30 is tightly fixed to the hole wall. On the other hand, when water is injected from the hole side packer pressure line 26, fluid pressure is applied between the casing 45 and the piston 44, and as a result, the piston 44 is pushed to the left in FIG. It is compressed via the metal ring 43 and expands in the radial direction, and the hole side packer portion 40 is also fixed to the hole wall in close contact. Next, when pressure water is supplied from the water injection line 22 to form a crack in the rock, the displacement of the opening of the formed crack can be measured by the displacement meter 27 as described with reference to FIG. Further, since the water injection line 22 is connected to the pressure gauge 25 attached to the tip of the packer, the water injection pressure is also measured at the same time.

Here, an example of use of the above-mentioned packer will be described. The actual site used was the tunnel at the Kamioka Mine Mozumi Pit in Gifu Prefecture. A 6-meter horizontal borehole with a diameter of 76 mm was excavated in the bedrock in the tunnel, and the above-mentioned packer was inserted therein. After tightly fixing both packers 30, 40 to the hole wall,
Water for crushing was injected from the water injection line 22, and the water injection section was pressurized to form a crack. Then, the opening displacement amount of the formed crack was measured by a displacement meter. The result is shown in FIG.
Shown in

From FIG. 4, water injection is started and the pressure is reduced to about 1
It can be seen that a crack was formed when the pressure increased to 30 kgf / cm ² . After that, if you continue to inject water,
Although the pressure decreases slightly, the width of the crack seems to continue to expand due to the pulsating pressure curve. And
After the water injection valve is closed and water injection is stopped, the opening displacement shows a decreasing tendency, but the pressure release valve is opened to reduce the pressure to 0 kg.
It can be seen that the crack was not completely closed even when lowered to f / cm ² .

[0015]

As described above, the use of the packer for hydraulic crushing of the present invention makes it possible to crack even when hydraulic crushing is carried out in a relatively deep borehole which does not penetrate. The opening displacement amount of the crack can be directly measured at the position where the crack is formed. Moreover, since the opening displacement of the crack is not restricted as in a conventional packer having a pair of rubber seals on one shaft, the original opening amount can be measured.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a packer according to the present invention.

FIG. 2 is a partial sectional view of a deeper side showing an embodiment of the packer according to the present invention.

FIG. 3 is a partial cross-sectional view of the same hole side.

FIG. 4 is a graph showing the results of an experimental example using the hydraulic crushing packer shown in FIGS. 2 and 3.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packer shaft 2 Deep side packer part 3 Hole side packer part 4 Rubber seal 5 Metal ring 6 Deep side packer pressure line 7 Water injection line 8 Hole side packer pressure line 9 Displacement gauge 10 Gripping tool 11 Pressure gauge 20 Packer shaft 21 Deep side Packer pressure line 22 Water injection line 23 Cable line 24 Tip cap 25 Pressure gauge 26 Hole side packer pressure line 27 Displacement meter 28 Gripping tool 30 Deep side packer part 31 Rubber seal 32 Metal ring 33 Piston 34 Casing 35 Coil spring 40 Hole side packer part 41 cylindrical member 42 rubber seal 43 metal ring 44 piston 45 casing 46 locking member 47 coil spring

Continuation of the front page (72) Inventor Mitsugu Yamashita 2-12-4 Sengen, Tsukuba, Ibaraki 105 Toyo Corp. (56) References JP 2-60837 (JP, B2) JP 6-7057 (JP) , Y2) (58) Field surveyed (Int. Cl. ⁶ , DB name) E21C 37/06 G01B 5/14

Claims (1)

(57) [Claims] 1. A packer unit comprising: a deeper side packer unit integrated with a packer shaft; and a hole side packer unit sliding on the packer shaft. Each of the packer units is compressed by a fluid pressure and is expandable in a radial direction. It has a rubber seal, a packer pressure line for applying fluid pressure to the deeper packer part and a water injection line for injecting pressurized water between both packer parts are provided through the packer shaft, and both A hydraulic crushing packer, wherein a displacement meter for measuring a relative displacement amount of the packer portion is attached to the packer shaft.