JP3184754B2 - Double tube Double packer Injection tube used for injection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner filling pipe used in a ground improvement method, particularly a double pipe double packer filling method which is one of chemical liquid filling methods.

[0002]

2. Description of the Related Art One of the ground improvement methods for improving the properties of the ground is a chemical liquid injection method. The chemical injection method is performed by drilling the ground and injecting cement, bentonite, water glass, and other chemicals into the ground from the excavation hole, and various methods have been developed.

One of the chemical liquid injection methods is a double pipe double packer injection method. Double pipe double packer injection method,
In recent years, it has achieved many construction results because it can reliably improve the target ground layer and can be repeatedly injected.

In the double pipe double packer injection method, first, a target ground is drilled with a casing, and then an injection outer pipe having injection holes at predetermined intervals in the axial direction is installed in the ground. The injection inner tube with a double packer, which has a chemical solution ejection hole at the top and bottom in the axial direction of the ejection hole, is inserted into the outer tube for injection, and the inner tube for injection is moved in the axial direction to thereby inject the inner tube for injection. Is a method of injecting a chemical solution into the ground for each step while sequentially stepping up from the innermost injection hole, with the ejection hole of the injection tube corresponding to the injection hole of the outer injection tube.

[0005] Various types of such injection inner tubes have been developed and provided. Among them, typical ones are (1)
There are O-ring double packers and (2) hydraulic double packers.

(1) The O-ring type double packer is such that a ring is fitted around the outer periphery of a solid packer so that a chemical solution to be injected into the ground does not leak from between the packers.

(2) The hydraulic double packer is of a type in which a balloon-like packer is inflated with high-pressure water and sealed.

[0008]

However, the prior art has the following problems.

(1) The O-ring type double packer includes:
(A) The packer according to the O-ring type double packer cannot be contracted because it is solid, and much friction is required between the outer periphery of the O-ring and the inner surface of the outer injection tube to insert and withdraw the inner injection tube. Requires,

(B) Since the inner tube is made of steel, it cannot be inserted if the outer tube is bent.

(C) Since the injection inner pipe is made of steel and short, there is a problem that a lot of labor and time are required for refilling and cutting off.

(2) 'The hydraulic double packer can contract the packer at the time of insertion and withdrawal to perform the work, so that the work can be performed very easily.

However, since (a) the inner tube of injection has a double tube structure composed of a system for injecting a chemical solution and a system for expanding and contracting the packer, the disassembling and assembling work at the time of cleaning the inner tube for injection, etc. It takes a lot of time to clean (chemicals (chemicals) solidify without cleaning, making subsequent use impossible)

(B) The diameter of the injection inner tube becomes large, and it is impossible to cope with a small diameter injection outer tube.

(C) Increasing the diameter of the outer injection tube in accordance with the diameter of the inner injection tube increases the amount of the drug solution to be injected, resulting in poor economic efficiency.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to reduce the labor required for insertion and withdrawal operations of the injection inner tube and to make the outer injection tube bent. Another object of the present invention is to provide an injection inner pipe used in a double pipe double packer injection method, which can be inserted even if it is used, and can simplify the structure and improve the economic efficiency.

[0017]

The gist of the present invention is to provide an ejection hole provided at a tip end portion, and an upper and lower expandable rubber and a lower packing which are respectively provided above and below the ejection hole. It is inserted into an injection outer tube having an injection hole at a predetermined interval in the axial direction, having rubber and installed in the ground, and moved in the axial direction to match the injection hole with the injection hole of the injection outer tube. A double-pipe double-packer injection method for injecting a chemical solution into the ground from each injection hole, a nozzle pipe provided with a discharge hole, and slidable inside the nozzle pipe. Provided is a spring assembly having a plunger that can open and close the ejection hole by the injection pressure of the chemical solution, and a biasing unit that urges the plunger so that the ejection hole is closed when the injection pressure of the chemical solution is not applied. Preparation Oil is sealed in a space surrounded by the plunger and the lower packer rubber so that the lower packer rubber expands and contracts by sliding of the plunger, so that the inside of the upper packer rubber, the ejection hole, and the plunger can be pressed. An injection inner pipe used for a double pipe double packer injection method, characterized in that a chemical injection path for communicating with a nozzle pipe and through which a chemical liquid pumped from the ground flows is formed inside. The gist of the invention according to claim 2 is to have an ejection hole provided at a tip portion, and upper and lower expandable rubbers and a lower packer rubber respectively provided above and below the ejection hole. It is inserted into the injection outer tube having an injection hole at a predetermined interval in the axial direction, and is moved in the axial direction to match the ejection hole with the injection hole of the injection outer tube, and the chemical solution from each injection hole is placed in the ground. A double-tube double-packer injection method,
A nozzle pipe provided with an ejection hole, a plunger slidably provided inside the nozzle pipe, capable of opening and closing the ejection hole by the injection pressure of the chemical, and an ejection hole in a state where the injection pressure of the chemical is not applied. And a biasing means for biasing the plunger so that the upper plunger is closed. The upper plunger is slidably fitted into an upper cylinder communicating with the inside of the upper packer rubber, and the upper plunger is Oil is sealed in a space surrounded by the upper packer rubber and the upper cylinder so that the upper packer rubber expands and contracts by sliding, and the upper cylinder and the ejection hole so that the upper plunger can be pressed.
A double nozzle, characterized in that a chemical solution injection flow path through which a chemical solution pumped from the ground flows inside is communicated with the nozzle pipe and the inside of the lower packer rubber so that the plunger can be pressed, It is in the inner pipe used for the pipe double packer injection method. The gist of the invention described in claim 3 is that the ejection holes provided at the tip portion, the ejection holes provided at the top and bottom of the ejection holes, and the ejection holes provided at the top and bottom of the ejection holes respectively. In addition, it has an expandable upper packer rubber and a lower packer rubber, is inserted into an injection outer tube having an injection hole at a predetermined interval in the axial direction, which is installed in the ground, and is moved in the axial direction. A nozzle pipe having an injection hole, which is used for a double-pipe double-packer injection method, in which the injection hole is made coincident with the injection hole of the injection outer tube, and a chemical solution is injected into the ground from each injection hole. A plunger slidably provided inside the nozzle pipe and capable of opening and closing the ejection hole by the injection pressure of the chemical, and a plunger such that the ejection hole is closed when no injection pressure of the chemical is applied. Energizing hand An upper plunger is slidably fitted in an upper cylinder communicating with the inside of the upper packer rubber, and the upper packer rubber is expanded and contracted by sliding of the upper plunger. Oil is sealed in the space surrounded by the upper cylinder and
Oil is sealed in a space surrounded by the plunger and the lower packer rubber so that the lower packer rubber expands and contracts by sliding of the plunger, and the upper cylinder, the ejection hole, and the plunger are pressed so that the upper plunger can be pressed. Injection used for the double pipe double packer injection method, characterized in that a chemical injection path is formed in the inside, which is communicated with the nozzle pipe so that it can be pressed, and in which the chemical liquid pumped from the ground flows inside. Exist in the inner tube.

Since the packer for the infusion tube according to the present invention can be expanded and contracted, the labor required for inserting and lifting the infusion tube can be reduced. Also, insertion is possible even if the outer injection tube is bent.

In addition, since it is not a double tube structure, it is possible to reduce the diameter. Therefore, the injection amount of the drug solution is reduced,
Enables improved economic efficiency.

Further, since the structure can be simplified, the disassembly and assembly work can be facilitated.

[0021]

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

(Embodiment 1) The injection inner pipe 100 according to Embodiment 1 is used for a double pipe double packer injection method. As shown in FIG. 1, it is schematically constituted by an inner tube main body 10, a spring assembly 130, and an upper packer assembly 110 and a lower packer assembly 120 which are connected vertically above and below the spring assembly 130. FIG. 1 shows an inner tube 100 for injection.
Is drawn as a cross section. Arrows in the figure indicate the flow of the chemical solution.

The inner tube body 10 is a hollow flexible tube extending to the ground. The base end of the inner tube main body 10 on the ground side is connected to a liquid injection device for injecting a chemical solution, and the front end is connected to the upper packer assembly 110.

The upper packer assembly 110 includes an upper packer pipe 111 serving as a base, packer nipples 112 respectively attached to upper and lower ends thereof, a packer cap 113 attached outside each packer nipple 112, and a packer nipple 112. And a packer rubber 114 fixed to the packer cap 113.

The upper packer pipe 111 is a steel tubular body in which an upper chemical liquid passage 111a penetrating in the axial direction is formed. A spanner hook 111b is formed on an outer surface of the upper part in the installed state. A joint portion 111c is formed at the upper end. A male screw is cut into the joint portion 111c, and the joint portion 111c is screwed with a female screw cut at the tip of the inner tube main body 10.

The packer nipple 112 is, as shown in FIG. 2, a substantially cylindrical body made of steel having a wrench hook 112a formed at one end. The tubular parts face each other when attached to the upper packer pipe 111. ing. The inner diameter of the packer nipple 112 is equal to the outer diameter of the upper packer pipe 111, and is fitted to the outer surface of the upper packer pipe 111. Spanner hook 112a on the outer surface of the cylindrical part
The flange 112b is formed at a slight interval from the flange 112b. With this flange 112b, a spanner hook 112a
A groove 112c is formed between the two. The flange 113a of the packer cap 113 is fitted in such a groove 112c.

The packer cap 113 is a substantially cylindrical body made of steel with the above-mentioned flange 113a formed at one end thereof toward the inside in the radial direction. The packer cap 113 is attached to the packer nipple 112 with the flanges 113a facing in opposite directions. Installed. The inner diameter is larger than the outer diameter of the packer nipple 112, and a cylindrical gap is formed in the mounted state. The both ends of the packer rubber 114 are fixed by being sandwiched in this gap. Packer rubber 114
Is a straight cylindrical body that can be expanded and contracted. A spring assembly 13 is provided at the lower end of the upper packer assembly 110.
0 is connected.

The spring assembly 130 includes a nozzle pipe 131 having an ejection hole 131b, and a plunger 13 slidably provided inside the nozzle pipe 131 and capable of opening and closing the ejection hole 131b by injection pressure of a chemical.
2, and return springs 133 and 134 (biasing means) for biasing the plunger 132 so as to close the ejection holes 131b when no injection pressure of the chemical solution is applied.

The nozzle pipe 131 is a steel tubular body in which a middle chemical liquid passage 131a penetrating in the axial direction is formed. Two ejection holes 131b for ejecting the chemical liquid, which communicate with the middle chemical liquid flow path 131a, are in communication. As shown in FIG. 4, the ejection hole 131 b is formed on the side of the upper end of the nozzle pipe 131 on the opposite side in the radial direction. A male screw 131c is cut in the upper part. This male screw 131
c is screwed to a connector 125 screwed to the lower end of the upper packer assembly 110.

The connector 125 is provided with a flange 125a at the center in the axial direction on the inner side surface. The inner diameter at the flange 125a is larger than the inner diameter at the upper end of the nozzle pipe 131. Therefore, the flange 125a protrudes radially inward, and the contact surface 1
25b are formed.

As shown in FIG. 1, the plunger 132 is a substantially cylindrical body having a solid outer contour, and seal rings 132a and 132b are fitted on the upper and lower sides in the axial direction. Plunger 13
The outer diameter of 2 is substantially equal to the inner diameter of the nozzle pipe 131. Therefore, the upper end of the plunger 132 contacts the contact surface 125b of the connector 125 in a state where the plunger 132 is urged by the return springs 133 and 134.

Return spring 1 shown in FIGS. 1 and 3
When the nozzles 33 and 134 are loaded in the nozzle pipe 131, their upper ends are in contact with the lower surface of the plunger 132 and are urged upward. The lower end is in contact with a contact surface 138a formed on the joint 138.

The joint 138 is connected to the nozzle pipe 131
It is screwed on a male screw 131d cut at the lower end of the. The lower packer assembly 120 is connected to the spring assembly 130 via such a joint 138.

The lower packer assembly 120 has substantially the same structure as the upper packer assembly 110. Oil O is sealed in a gap surrounded between the inside of the lower packer assembly 120 and the lower surface of the plunger 132. A tip cap 121 is screwed to the outer surface of the lower end. In the figure, the same components as those of the upper packer assembly 110 are denoted by the same reference numerals. In the figures, reference numerals 150 to 15
Reference numeral 4 denotes an O-ring for sealing a chemical solution.

As shown in FIG. 1, the upper packer pipe 11
1, the nozzle pipe 131, and the lower packer pipe are connected to each other, the upper chemical liquid flow path 111 a and the middle chemical liquid flow path 131 a form a chemical liquid injection flow path 140.

Next, a construction method will be described.

After drilling the ground with a casing, the outer pipe for injection 1 shown in FIG. 4 is installed in the casing, and then the casing is pulled out and the outer pipe for injection 1 is set in the ground G.

Next, the injection inner tube 10 with a double packer
0 is inserted into the outer tube 1 for injection.

Next, the inner injection tube 100 is moved in the axial direction so that the ejection hole 131b of the inner injection tube 100 coincides with the deepest injection hole 2 of the outer injection tube 1.

Next, the chemical is pumped from the ground into the chemical injection channel 140 to expand the packer rubbers 114 and 114, and the chemical M is injected into the ground G through the injection hole 2.

Next, the injection hole 131b is aligned with the injection hole immediately above by moving the injection inner tube 100 upward,
The chemical M is injected into the ground G from the injection hole.

This process is sequentially performed up to the uppermost injection hole, and the chemical M is injected into the ground G from each injection hole.

Next, the operation of the inner tube 100 will be described.

The chemical solution injection flow path 140 is passed through the inner pipe main body 10.
As shown in FIG. 6, the chemical solution M inflates the upper packer assembly 110 and presses the packer rubber 114 against the inner surface of the outer injection tube 1 to press the outer liquid tube 1 as shown in FIG.
And the gap between the inner tube 100 and the injection tube 100 are closed.

At the same time, as shown in FIGS. 5 and 6,
The chemical M flows into the middle chemical flow channel 131a, and the plunger 132 is pushed down by the injection pressure of the chemical M. When the plunger 132 is pushed down, the packer rubber 114 (not shown in FIG. 5) of the lower packer assembly 120 is expanded by the oil O (not shown in FIG. 5), and the packer rubber 114 is pressed against the inner surface of the outer filling tube 1. hand,
The gap between the outer tube 1 and the inner tube 100 is closed.

On the other hand, when the plunger 132 is pushed down, the ejection hole 131b is opened, and the chemical M is ejected from the ejection hole 131b. Therefore, the spring coefficients of the springs 133 and 134 are determined from the above operation. That is, the chemical M
The injection pressure may be such that the packing of the packer rubber 114 can be completely closed and the plunger 132 has a spring coefficient capable of pushing down.

When the press-fitting of the chemical solution M is stopped, the two packer rubbers 114, 114 contract due to their own contracting force. On the other hand, the ejection of the chemical solution M from the valve assembly 130 also stops.

By such an operation, the chemical liquid M can be injected from the deepest injection hole to the shallowest injection hole.

Next, the effect of the injection inner tube 100 will be described.

The inner pipe used for the double pipe double packer injection method is capable of expanding and contracting the packer.
The labor required for the zero insertion work and the lifting work can be reduced. Further, even if the outer injection tube 1 is bent, it can be inserted.

Further, since there is no need to provide a flow path for pressurizing the packer separately from the chemical liquid injection flow path 140, the injection inner pipe 10
0 can be simplified. Therefore, it is possible to cope with the small-diameter outer injection tube 1. As a result, it is possible to reduce the hole diameter of the inner injection pipe 100 and the outer injection pipe 1, reduce the injection amount of the chemical solution, and reduce the construction cost.

Further, since the structure can be simplified, the manufacturing cost of the injection inner tube 100 can be reduced. Also,
Assembly, disassembly, cleaning, and the like can be easily performed. As a result, the construction period can be shortened, and the construction cost can be reduced.

The packer rubber 114,
114 can be expanded so that the packing rubber 1
A fluid for inflating 14, 114 and a pressurizing device for pressurizing the fluid are not required. Therefore, it is possible to reduce the cost and running cost of the entire chemical liquid injector including the pressurizing device and the like installed on the ground, and to reduce the construction cost.

The injection of the chemical M and the packing rubber 1
Since the expansion of 14, 114 can be performed at the same time,
Construction time can be reduced.

(Embodiment 2) As shown in FIG. 7, an injection inner tube 200 according to Embodiment 2 includes an inner tube main body 10 and an ejection hole 231b connected to the inner tube main body 10 by a connector 215. Spring assembly 2 having
30 and an upper packer assembly 210 and a lower packer assembly 240 connected vertically in the axial direction of the spring assembly 230. The arrows in the figure indicate the flow of the chemical.

The upper packer assembly 210 has a pair of packer nipples 211 located at both upper and lower ends thereof,
A packer cap 212 attached to the outside of each packer nipple 211, and an upper packer rubber 2 fixed to the packer nipple 211 and the packer cap 212
13 is provided.

As shown in FIG. 8, the packer nipple 211 is a nipple having a spanner hook 211a formed in the center and having the same inner diameter in any longitudinal section. An external thread 211b is formed at one end, and a flange 211c is formed at a slight distance from the external thread 211b. With this flange 211c, a spanner hook 211a
A groove 211d is formed between the two. The flange 212a of the packer cap 212 is fitted into the groove 211d.

The packer nipple 211 is attached to the packer cap 212 with the flanges 212a facing in opposite directions.
It is a substantially cylindrical body made of steel attached to the. Tsuba 212a
Is formed at one end toward the inside in the radial direction. A female screw 212b is cut on the inner peripheral surface. The inner diameter is larger than the outer diameter of the packer nipple 211, and a cylindrical gap is formed between the male screw 211 b and the female screw 212 b of the packer nipple 211 when attached to the packer nipple 211. Both ends of the upper packer rubber 213 are fixed by being screwed into this gap.

As shown in FIG. 7, the upper packing rubber 213 is a straight cylindrical body which can be expanded and contracted. The pair of packer nipples 211 is formed by the upper packer rubber 213.
Is connected.

An upper chemical liquid passage 214 is formed inside the packer nipple 211 and the upper packer rubber 213.

A spring assembly 230 is connected to a lower end of the upper packer assembly 210.

The spring assembly 230 includes a nozzle cylinder 231 and a plunger 232 inserted into the nozzle cylinder 231.

The nozzle cylinder 231 is a steel cylinder, and has an ejection hole 231b at the top. The ejection holes 231b are opened one by one on the opposite side in the radial direction. An air vent hole 231c is opened in the lower part. Female threads are cut at both ends, female threads at the upper end are screwed to male threads cut at the lower end of the packer nipple 211, and female threads at the lower end are threaded to male threads cut at the upper packer nipple 241. . The inner diameter of the nozzle cylinder 231 is
It is larger than the inner diameter of the packer nipple 211. In a state where the plunger 232 is pushed down, a chemical solution can flow into the nozzle cylinder 231 and becomes a middle chemical solution flow path 231a. In the drawings, reference numerals 232c and 232d are seal rings.

The plunger 232 has an upper head 232a and a lower head 232b formed at both ends thereof, and has a circular cross section in each section. The upper head 232a slides inside the nozzle cylinder 231. The inner diameter of the upper packer nipple 241 is smaller than the inner diameter of the nozzle cylinder 231, and the lower head 232 b slides inside the upper packer nipple 241. Therefore,
The diameter of the lower head 232b is smaller than the diameter of the upper head 232a. The lower head 232b is urged upward by a return spring 233 abutting on the lower surface thereof. Most of the return spring 233 is housed inside the lower packer assembly 240, and its lower end is in contact with the tip cap 270. Since the diameter of the upper head 232a is larger than the diameter of the lower end of the packer nipple 211, when the pressure is not applied to the chemical solution, the upper surface of the upper head 232a is in contact with the lower end of the packer nipple 211 by the return spring 233. Become. In such a state, the upper head 23
2a is a state in which the ejection hole 231a is closed. When the upper head 232a is pressed down by the injection pressure of the chemical, the ejection hole 231a is opened.

The lower packer assembly 240 includes a pair of packer nipples 241, 242, a packer cap 243, and a lower packer rubber 244.

The upper packer nipple 241 is similar to the packer nipple 211 of the upper packer assembly 210. The lower packer nipple 242 is connected to the packer nipple 211 of the upper packer assembly 210.
Is similar to The lower end is closed by a tip cap 270.

The packer cap 243 and the lower packer rubber 244 are the same as the packer cap 212 and the upper packer rubber 213 of the upper packer assembly 210.

The lower end face of the lower head 232b, the upper packer nipple 241 and the lower packer nipple 242
234 surrounded by the lower packer rubber 244
Is filled with oil O. Therefore, when the plunger 232 is pushed down by the chemical solution, the oil O expands the lower packer rubber 244.

As described above, the upper packer assembly 2
10, the spring assembly 230 and the lower packer assembly 240 are connected, the upper chemical liquid flow path 214 and the middle chemical liquid flow path 23 communicating with the ejection hole 231b.
With 1a, the chemical solution injection channel 250 is formed inside. In the figure, reference numerals 260, 261 and 263 are O-rings for sealing a chemical or oil O.

The construction method is the same as in the first embodiment.

Next, the operation of the inner pipe used in the double pipe double packer injection method will be described.

As shown in FIG. 9, when the chemical solution M is press-fitted into the injection flow channel 250 through the inner tube main body 10, the chemical solution M flows into the upper packer rubber 213 to expand the same, and The inner tube of the outer tube 1 is pressed. Further, the chemical solution M presses the upper head 232a, and presses down the plunger 232. At this time, the lower head 232 b transmits the pressure to the oil O, causes the oil O to flow into the lower packer rubber 244, expands the oil O, and presses the oil O against the inner surface of the outer injection tube 1. As a result, a closed space is formed between the upper packing rubber 213 and the lower packing rubber 244.

On the other hand, the injected chemical solution M is used in the first embodiment.
Similarly to the above, the chemical liquid M flows from the middle chemical liquid flow path 231a into the ejection hole 231b, and is ejected into the space.

The diameter of the upper head 232a is
Since it is larger than the diameter of 32b, the lower packer rubber 244 can be expanded with a small injection pressure of the liquid medicine M.
A specific example of such an operation will be described below based on the design example of the inventor.

D ₁ = 16 mm, D ₂ = 10 mm, A ₁ = 2.01 cm ² , A ₂ = 0.79 cm ² D ₁ : diameter of upper head 232 a, D ₂ : lower head 2
A ₁ : area of upper head 232 a, A ₂ : lower head 2
32b of the area P _1: pressure right exerted on the upper head 232a (chemical solution M injection pressure) P _2: pressure of the left applied to the lower head 232b (the pressure to inflate the packer rubber)

[0076] Given the Hitoshiri fit state from the principle of Pascal, the reaction force of _{P 1 A 1 = P 2 A} 2 return spring 233, and considering the sliding _{resistance, P 1 A 1 = P 2} A 2 + ( Reaction force of return spring 233 +
Sliding resistance)

[0077] _{Therefore, P 2 = (A 1 /} A 2) ( reaction force + sliding resistance of the return spring 233) P ₁ over / reaction force + sliding resistance of A ₂ = 2.54P ₁ over (return spring 233 ) / A ₂ .

Here, if P ₂ > P ₁ , the packer rubber can be expanded by a small injection pressure.

In the above equation, assuming that the right side is 2.54 P _1- (reaction force of return spring 233 + sliding resistance) / A ₂ = XP ₁ , if X> 1, then P ₂ > P ₁ Becomes

[0080] When the sliding resistance is constant, the spring constant of the return spring 233, (reaction force + sliding resistance of the return spring 233) 2.54P ₁ over _{/ A 2> 1P 1 1.54P 1} > ( return spring If the adjustment is made so that the reaction force of 233 + the sliding resistance) / A ₂ (1), P ₂ > P ₁ .

On the other hand, assuming that the plunger is movable, the reaction force of the return spring 233 must be greater than the sliding resistance (2). Therefore, if the spring constant of the return spring 233 is determined so as to satisfy the above equations (1) and (2), (P ₃ >)> P ₂ > P ₁ and it becomes movable. P ₃ is the actual injection pressure in consideration of the loss due to fluid resistance, friction and the like.

As described above, if the spring constant of the return spring 233 is determined, it is possible to sufficiently close the packer rubber.

When the injection of the liquid medicine M is stopped, the upper packer rubber 213 and the lower packer rubber 2
44 contracts, and the ejection of the chemical M from the ejection holes 231b also stops.

Further, the return spring 23 urged is
3, the plunger 232 is returned to the position before the injection of the liquid medicine M.

By such an operation, the chemical liquid M can be injected from the deepest injection hole to the shallowest injection hole.

The inner injection tube 200 according to the second embodiment has a slightly complicated structure in that the plunger 232 is used, as compared with the inner injection tube according to the first embodiment. The effects listed in 1 can be obtained.

Furthermore, the injection inner tube 20 according to the second embodiment
In the case of 0, the packer rubber of the lower packer assembly 240 is expanded by the oil O, so that the failure due to the solidification of the chemical liquid M does not occur. Therefore, the disassembly and assembly work of the lower packer assembly 240 can be eliminated.

In the second embodiment, oil O is used as a liquid for expanding lower packer rubber 244.
However, the present invention is not limited thereto, and water, other liquids, gas, and the like suitable for carrying out the present invention can be used.

(Embodiment 3) As shown in FIG. 10, an injection inner tube 300 according to Embodiment 3 comprises an inner tube main body 10 and
Spring assembly 330 having ejection holes 331b
And an upper packer assembly 310 and a lower packer assembly 340 which are connected vertically in the axial direction of the spring assembly 330, and have substantially the same configuration as that of the first embodiment. Embodiment 1 has a structure in which the upper packer rubber is expanded with a chemical solution and the lower packer rubber is expanded with oil. On the other hand, in the third embodiment, the upper packer rubber 314 is also expanded by the oil O. The arrows in the figure indicate the flow of the chemical.

The upper packer assembly 310 is connected to the inner pipe main body 10 via the upper plunger assembly 320.
Is connected to

The upper plunger assembly 320 includes an upper cylinder 321 and an upper plunger 322 inserted into the upper cylinder 321.

The upper cylinder 321 is a substantially cylindrical body made of steel, has female threads cut at both ends, an adapter 301 is screwed at the upper end, and an upper packer nipple 311 is screwed at the lower end. ing.

The upper plunger 322 is shown in FIGS.
As shown in FIG. 2, it has a short cylindrical shape. As shown in FIG. 11, a thin portion 322a having a small outer diameter is formed at an upper portion, and a thin portion 322b is formed at a boundary with other portions. It is urged upward by a return spring 323 that contacts the lower surface. As shown in FIG. 10, the lower end of the return spring 323 is in contact with the upper end surface of the upper packer nipple 311. In a state where no pressure is applied to the chemical solution, as shown in FIG.
01 (not shown in FIG. 11) and a gap between a flow path pipe 325 to be described later, and the step 322 b comes into contact with the lower end surface of the adapter 301.

The upper packer assembly 310 is substantially the same as the lower packer assembly according to the second embodiment except that the lower end is not closed by the tip cap. However, as shown in FIG. 10, the upper packer nipple 311 has a thinner external thread than the lower packer nipple 312. Therefore, an oil passage 313 shown in FIGS. 10 and 14 is formed between the oil passage 313 and the passage pipe 325 described below.

As shown in FIGS. 10 and 13, the flow path pipe 325 forms the upper chemical liquid flow path 326 with a straight steel pipe. The upper plunger 322 and the lower packer nipple 312 are fitted. Therefore, the upper plunger 322 is connected to the upper cylinder 321 and the flow pipe 3
25 will slide. Further, oil O described later does not leak from between the lower packer nipple 312 and the flow path pipe 325. A cylindrical space equal to the thickness of the upper plunger 322 is formed between the outer surface of the flow pipe 325 and the inner surface of the upper cylinder 321. A space is also formed between the upper packing rubber 314 and the upper packing rubber 314. Both spaces are oil flow path 3
13 are communicated.

Oil O is sealed in both spaces and the oil flow path 313. Therefore, the upper plunger 32
When 2 is pushed down by the chemical, the upper packer rubber 314 is expanded by the oil O.

The spring assembly 330 has the same configuration as the spring assembly 130 according to the first embodiment. The components indicated by reference numerals 330 to 338 according to the third embodiment correspond to the components indicated by reference numerals 130 to 138 according to the first embodiment.

The lower packer assembly 340 has the same configuration as the lower packer assembly according to the first embodiment. However, in the third embodiment, reference numeral 342 in the figure is a lower packer rubber.

As described above, when the upper plunger assembly 320, the upper packer assembly 310, the spring assembly 330, and the lower packer assembly 340 are connected, the upper cylinder 321 capable of pressing the upper plunger 322 and the upper chemical liquid flow Road 326,
The chemical solution injection channel 350 is formed inside by the middle chemical solution channel 331a.

In the figure, reference numerals 360 to 364 denote O-rings for sealing a chemical or oil O.

The construction method is the same as in the first embodiment.

Next, the operation of the inner tube for injection used in the double tube double packer injection method will be described.

As shown in FIG. 15, when the chemical M is press-fitted into the chemical injection flow path 350 via the inner pipe main body 10, the chemical M
Flows into the lower packer rubber 342 to expand it,
The tube is brought into contact with the inner surface of the outer injection tube 1. Further, the chemical solution M pushes down the upper plunger 322. At this time, the pressure is transmitted to the oil O, and the oil O is caused to flow into the upper packer rubber 314, expanded, and brought into contact with the inner surface of the outer filling tube 1. As a result, a closed space is formed between the upper packer rubber 314 and the lower packer rubber 342.

On the other hand, the press-fitted chemical liquid M is jetted from the middle chemical liquid flow path 331a into the space through the jet holes 331b.

When the injection of the chemical solution M is further continued, the chemical solution M is injected into the ground G through the injection hole 2.

Since the inner injection tube 300 according to the third embodiment is configured as described above, the same effects as those of the inner injection tube according to the first and second embodiments can be obtained.

(Embodiment 4) In Embodiment 4, another embodiment of the spring assembly will be described.
As shown in FIGS. 16 and 17, the spring assembly 430 includes a nozzle pipe 431 and a plunger 432.
And

[0108] The nozzle pipe 431 is a double pipe, and a jet hole 431b is formed in an outer pipe 431c. A middle chemical liquid flow path 431a is formed inside the inner pipe 431d. The middle chemical liquid flow path 431a communicates with an upper chemical liquid flow path and a lower chemical liquid flow path (not shown) to form a chemical liquid injection flow path. A plunger 432 is fitted in a gap between the outer tube 431c and the inner tube 431d.

The plunger 432 has a hollow cylindrical shape and is urged upward by a spring 433 as in the first to third embodiments.

In such a spring assembly 430, the plunger 432 is pushed down by the chemical liquid M, and the chemical liquid M flows through the middle chemical liquid flow path 431a to the lower chemical liquid flow path. Therefore, the lower packer rubber (not shown) can be expanded by the chemical.

The same function and effect as those of the first to third embodiments can also be obtained in the injection inner tube having the spring assembly having the above-described configuration.

The number, position, shape, and the like of the above-mentioned constituent members are not limited to those in the first to fourth embodiments. For example, the number, the position, and the like suitable for carrying out the present invention, such as the number, the position, and the like of the ejection holes. ,
It can be shaped and the like.

Further, as the chemical solution, for example, water glass, cement bentonite, cement milk and the like can be made suitable for carrying out the present invention.

[0114] The packing rubber may be fixed by a method suitable for the present invention, such as a method of pinching and fixing as shown in FIG. 1 and a method of screwing as shown in FIG. Rubber can be fixed.

The number of return springs, wire diameter, etc.
It can be made suitable for carrying out the present invention.
Further, it is not necessary to provide a return spring.

In each of the drawings, the same components are denoted by the same reference numerals.

[0117]

Since the present invention is configured as described above, the following effects can be obtained. Since the packer for the infusion tube according to the present invention can be expanded and contracted, the labor required for the insertion and lifting operations of the infusion tube can be reduced. Further, even if the outer injection tube is bent, it can be inserted.
In addition, since it is not a double pipe structure, it is possible to reduce the diameter. Therefore, the hole diameter can be reduced and the injection amount of the chemical solution can be reduced, so that the economic efficiency can be improved. Further, since the structure can be simplified, the disassembling and assembling work can be facilitated.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view of an inner injection tube according to Embodiment 1.

FIG. 2 is an enlarged view of a packer nipple in a connected state.

FIG. 3 is a sectional view taken along line C1-C1 of FIG. 1;

FIG. 4 is a sectional view taken along line C2-C2 of FIG. 1;

FIG. 5 is a partial cross-sectional side view showing an operation of the plunger according to the first embodiment.

FIG. 6 is a partial cross-sectional side view showing the operation of the infusion tube according to the first embodiment.

FIG. 7 is a partial cross-sectional side view of an infusion tube according to a second embodiment.

FIG. 8 is an enlarged view of the packer nipple in a connected state.

FIG. 9 is a partial cross-sectional side view showing the operation of the infusion tube according to the second embodiment.

FIG. 10 is a partial cross-sectional side view of an infusion inner tube according to a third embodiment.

FIG. 11 is an enlarged view of an upper end portion of an upper cylinder.

FIG. 12 is a sectional view taken along line S1-S1 of FIG. 7;

FIG. 13 is a sectional view taken along line S2-S2 of FIG. 7;

FIG. 14 is a sectional view taken along line S3-S3 of FIG. 7;

FIG. 15 is a partial cross-sectional side view showing the operation of the infusion tube according to the third embodiment.

FIG. 16 is a partial cross-sectional side view of a spring assembly according to a fourth embodiment.

FIG. 17 is a sectional view taken along line XX of FIG. 16;

[Explanation of symbols]

 G Ground M Chemical O Oil 1 Injection Outer Pipe 2 Injection Hole 10 Inner Pipe Main Body 100 Injection Inner Pipe 110 Upper Packer Assembly 111 Upper Packer Pipe 111a Upper Chemical Flow Path 111b Spanner Hanging 111c Joint Part 112 Packer Nipple 112a Spanner Hook 112b Flange 112c Groove 113 Packer cap 113a Flange 114 Packer rubber 120 Lower packer assembly 121 Tip cap 125 Connector 125a Flange 125b Contact surface 130 Spring assembly 131 Nozzle pipe 131a Middle chemical liquid flow passage 131b Spout hole 131c Male screw 131d Male screw 132 Plunger 132a Seal ring 132b Seal ring 132b Return spring 134 Return spring 138 Joint 1 0 Chemical liquid injection channel 150, 151, 152, 153, 154 O-ring 200 Injection inner tube 210 Upper packer assembly 211 Packer nipple 211a Spanner hook 211b Male screw 211c Flange 211d Groove 212 Packer cap 212a Flange 212b Female screw 213 Upper packer rubber 214 Upper chemical Flow path 215 Connector 230 Spring assembly 231 Nozzle cylinder 231a Middle chemical liquid flow path 231b Spray hole 231c Air vent hole 232 Plunger 232a Upper head 232b Lower head 232c Seal ring 232d Seal ring 233 Return spring 234 Space 240 Lower packer assembly 241 Upper packer 242 Lower packer nipple 243 Packer cap 24 4 Lower Packer Rubber 250 Chemical Injection Flow Path 260, 261, 263 O-Ring 270 Tip Cap 300 Injection Inner Pipe 301 Adapter 310 Upper Packer Assembly 311 Upper Packer Nipple 312 Lower Packer Nipple 313 Oil Flow Path 314 Upper Packer Rubber 320 Upper Plunger Assembly 321 Upper cylinder 322 Upper plunger 322a Thin portion 322b Step portion 323 Return spring 325 Flow pipe 326 Upper chemical liquid flow path 330 Spring assembly 331 Nozzle pipe 331a Middle chemical liquid flow path 331b Spout hole 331c Male screw 331a Male screw ring 332b Pier ring 332b 333 spring 334 spring 338 joint 340 lower packer assembly Buri 342 lower packer rubber 350 liquid injection passage 360,361,362,363,364 O-ring 430 spring assembly 431 nozzle pipe 431a Central chemical liquid flow path 431b injection holes 431c outer tube 431d inside the tube 432 plunger 433 spring

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-48518 (JP, A) JP-A-4-14514 (JP, A) JP-A-6-207410 (JP, A) JP-A-50-48 138607 (JP, A) JP-A-55-142818 (JP, A) JP-A-52-113506 (JP, A) JP-A-3-36024 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 3/12

Claims (3)

(57) [Claims] 1. A shaft having a spout hole provided at a tip end portion, and upper and lower expandable rubbers provided above and below the spout hole, respectively, and installed in the ground. The injection hole is inserted into the outer tube having an injection hole at a predetermined interval in the direction, and is moved in the axial direction so that the ejection hole coincides with the injection hole of the injection outer tube, and the liquid medicine is injected into the ground from each of the injection holes. An injection inner pipe used for a double pipe double packer injection method, comprising: a nozzle pipe provided with the ejection hole; and a slidably provided inside of the nozzle pipe, the injection pressure of the chemical solution. A spring assembly having a plunger capable of opening and closing the ejection hole, and an urging means for urging the plunger so that the ejection hole is closed when no injection pressure of the chemical solution is applied; Oil is sealed in a space surrounded by the plunger and the lower packer rubber so that the lower packer rubber expands and contracts by sliding of the jar, and the inside of the upper packer rubber, the ejection hole, and the plunger The double pipe double packer injection method, characterized in that a chemical liquid injection flow path through which the chemical liquid pumped from the ground flows inside is formed inside the nozzle pipe so as to be able to press the nozzle pipe. Infusion inner tube to use. 2. A shaft having a spout hole provided at a tip end portion, and an upper and lower expandable rubber and a lower packer rubber respectively provided above and below the spout hole, and installed in the ground. The injection hole is inserted into the outer tube having an injection hole at a predetermined interval in the direction, and is moved in the axial direction so that the ejection hole coincides with the injection hole of the injection outer tube, and the liquid medicine is injected into the ground from each of the injection holes. An injection inner pipe used for a double pipe double packer injection method, comprising: a nozzle pipe provided with the ejection hole; and a slidably provided inside of the nozzle pipe, the injection pressure of the chemical solution. A spring assembly having a plunger capable of opening and closing the ejection hole, and an urging means for urging the plunger so as to close the ejection hole when no injection pressure of the chemical solution is applied; An upper plunger is slidably fitted into an upper cylinder communicating with the interior of the rubber, and is surrounded by the upper packer rubber and the upper cylinder such that the sliding of the upper plunger causes the upper packer rubber to expand and contract. Oil is sealed in a space to be pressed, and communicates with the upper cylinder so as to press the upper plunger, the ejection hole, the nozzle pipe so as to press the plunger, and the inside of the lower packer rubber. And, characterized in that the medicinal solution pumped from the ground is formed inside the medicinal solution injection flow channel that flows inside,
Double pipe Double piper Internal pipe used for injection method. 3. A shaft having a spout hole provided at a tip end portion, and upper and lower expandable rubber rubbers provided above and below the spout hole, respectively, and installed in the ground. The injection hole is inserted into the outer tube having an injection hole at a predetermined interval in the direction, and is moved in the axial direction so that the ejection hole coincides with the injection hole of the injection outer tube, and the liquid medicine is injected into the ground from each of the injection holes. An injection inner pipe used for a double pipe double packer injection method, comprising: a nozzle pipe provided with the ejection hole; and a slidably provided inside of the nozzle pipe, the injection pressure of the chemical solution. A spring assembly having a plunger capable of opening and closing the ejection hole, and an urging means for urging the plunger so as to close the ejection hole when no injection pressure of the chemical solution is applied; An upper plunger is slidably fitted into an upper cylinder communicating with the interior of the rubber, and is surrounded by the upper packer rubber and the upper cylinder such that the upper plunger expands and contracts by sliding of the upper plunger. Oil is sealed in a space surrounded by the plunger and the lower packer rubber so that the lower packer rubber expands and contracts by sliding of the plunger, and presses the upper plunger. The upper cylinder, the ejection hole, and the nozzle pipe are connected to the nozzle pipe so as to be able to press the plunger, and a chemical solution injection flow path through which the chemical solution pumped from the ground flows is formed inside. Injection inner pipe used for the double pipe double packer injection method, characterized in that: