JP3023743B2 - How to connect non-concentric multiple pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the purpose of injecting a plurality of types of chemicals for ground improvement into the ground, and to connect continuous pipes in which an inner pipe for forming an electric circuit is housed in an outer pipe. The present invention relates to a connection method, and more particularly to a connection method of a non-concentric multi-connected pipe in which connecting pipes are screw-connected while connecting non-concentric inner pipes.

[0002]

2. Description of the Related Art A chemical is injected into the ground for the purpose of shielding the ground and strengthening the ground. The liquid to be injected is mainly a two-liquid mixed type mainly composed of water glass, and there are inorganic, organic or suspension type, solution type, etc. as the reactant. Depending on the purpose of injection and the target ground, The strength after consolidation, permeability to ground, time until consolidation (gel time), etc. are selected and used. In particular, in the chemical injection method called the compound injection method, the injection range is limited by initially injecting a chemical liquid with a short setting time called the instantaneous setting type, and then performing permeation injection with a long setting time. Use reactants. As a method of injecting the chemical, the injection liquid is supplied from a ground injection pump through a hose and a water swivel to an injection tube constituted by a double tube or a multiple tube and a tip injection device called a monitor. That is, after drilling to a predetermined depth using a monitor with a bit (drilling edge) attached to the tip, a boring rod (drilling rod) having a double or multi-tube structure, At predetermined depths (steps), a predetermined amount of the chemical is injected into the ground, and this operation is repeated as designed. Further, when a measurement sensor for determining the effect of injecting a chemical solution is installed at the bottom of the hole, or when using an instrument driven at the bottom of the hole, the signal sensor or power line is used as a part of an electric circuit. An inner tube is applied, and a waterproof connector or the like can be used for connecting the tubes.

FIG. 5 is a cross-sectional view of a conventional triple-tube type liquid injector. In the outer tube 27, a concentric tube 28 and a central tube 29 are disposed concentrically with an appropriate gap therebetween. The medicinal solution is placed in the central tube 29 (shown by A) and the concentric tube 2.
It is injected into the gap between the outer tube 27 and the concentric tube 28 (shown by C) and the gap between the outer tube 27 and the concentric tube 28 (shown by B).

[0004] Also, as a publication related to the injection of chemicals, there is "New Edition Grout Handbook" published by the first edition on July 4, 1972 (published by LaTeis Co., Ltd., 15-
9, 03-3267-2561). In this book, a double tube structure for injecting a chemical is described in various places.

[0005] On the other hand, there are very many publications relating to a liquid injector, for example, there is one disclosed in Japanese Patent Publication No. 60-2450. The drawings in this publication also disclose the structure of the injection tube.

[0006]

The conventional liquid injection tube shown in FIG. 5 has the outer tube 27, the concentric tube 28 and the center tube 29 concentrically arranged as described above. As described above, it is convenient to use a screw connection to connect the connecting pipes. For this purpose, the inner pipe is connected to the outer pipe 2 such as the concentric pipe 28 and the center pipe 29.
7 must be arranged concentrically. On the other hand, in the prior art, there was also a continuous pipe in which the inner pipe was arranged non-concentrically,
In such a case, the connecting pipes were connected by a flange joint or the like that does not require a rotational connection. However, flange joints are not widely used for drilling small diameter holes such as boring due to the fact that the appearance of the flange joints is not uniform and it is difficult to take countermeasures against collapse of the hole wall, and it takes time to tighten the bolts of the flange. . In that respect, the one that connects a continuous pipe with a concentric inner pipe by screw connection is easy to handle, but as the number of chemicals to be injected increases, the channel area decreases,
In addition, the arrangement of a large number of inner pipes concentrically has a problem that the supporting structure and the like are complicated and expensive.

The present invention solves the above-mentioned problems, and can make the flow passage area of the inner pipe for passing various kinds of chemicals and the like relatively large, as well as screw connection and easy handling. It is an object of the present invention to provide a method for connecting non-concentric multiple pipes which can be implemented at low cost.

[0008]

According to the present invention, in order to achieve the above-mentioned object, a connecting pipe having an outer pipe and a plurality of inner pipes disposed non-concentrically inside the outer pipe is connected to each other. A connection method, wherein the inner pipe is fitted into a fitting hole of a spacer, and the spacer is sandwiched between the two connecting pipes while screwing the upper connecting pipe and the lower connecting pipe together. Is characterized by the following connection method. Furthermore, the spacer is fixed to the connecting pipe on the side that is not screwed, and the spacer is prevented from rotating due to the frictional force generated between the upper connecting pipe and the spacer when screwing, so that quick and reliable connection is achieved. The method is characterized by a method of connecting non-concentric multiple pipes which performs the following.

[0009]

The inner pipes of the upper pipe and the lower pipe are connected to each other via a spacer. In this state, the upper connecting pipe and the lower connecting pipe are screw-connected. Since the spacer is provided in the two connecting pipes, the spacer is sandwiched between the two connecting pipes and solidified by screw connection. As described above, the inner pipes on the upper side and the lower side communicate with each other, and the two connecting pipes are connected by the screw connection. Further, by fixing the spacer to the connecting pipe on the side not to be screwed, rotation of the spacer at the time of screwing is prevented, and quick and reliable connection can be achieved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an axial sectional view showing a connection state of the present embodiment, FIG. 2 is a transverse sectional view taken along line DD of FIG. 1, FIG. 3 is an axial sectional view of another embodiment of the present invention, and FIG. FIG. 4 is a schematic axial sectional view showing injection of a chemical solution by the method.

As shown in FIGS. 1 and 2, the present embodiment employs an upper connecting pipe 1 (upstream connecting pipe) and a lower connecting pipe 2 (downstream connecting pipe).
Shows the case of connecting The upper and lower connecting pipes 1 and 2 have an upper outer pipe 3 and a lower outer pipe 4 (hereinafter, referred to as outer pipes 3 and 4) having the same outer diameter, and a first loosely inserted therein.
From the upper inner pipe 5, the second upper inner pipe 6 (hereinafter, referred to as inner pipes 5, 6), the first lower inner pipe 7, and the second lower inner pipe 8 (hereinafter, referred to as inner pipes 7, 8). Be composed. As described above, the inner tubes 5, 6 and 7, 8 are loosely inserted into the outer tubes 3 and 4, but are held by the holder 9, and are restricted from freely moving in the outer tubes 3 and 4. It is arranged almost in a fixed position. Further, an external screw 11 is threaded by an appropriate length downward from the upper end surface 10 of the outer tube 4. On the other hand, an inner screw 13 that is screwed into the outer tube 3 from the lower end surface 12 of the outer tube 3 is threaded, and a diameter-enlarging portion 17 of a spacer 16 described later is formed.
An inner hole 14 (substantially equal to the thread root diameter) into which the small hole 15 fits, and a small inner hole 15 into which the reduced diameter portion 18 of the spacer is fitted are formed, and a step 19 is formed between the inner hole 14 and the small inner hole 15. Is done.

As shown in FIG. 1, the spacer 16 has a two-stage cylindrical shape having an enlarged diameter portion 17 and a reduced diameter portion 18.
Fitting holes into which the inner tubes 5 and 6 fit are formed in the upper reduced diameter portion 18, and fitting holes into which the inner tubes 7 and 8 fit into the lower enlarged portion 17, respectively. You. The upper and lower fitting holes are communicated by communication holes 20, 21 which are substantially equal to the inner diameters of the inner tubes 5 (7) and 6 (8). In addition, the enlarged diameter portion 1
The width dimension of the outer tube 1 in the axial direction of the outer tube 1 is such that the enlarged diameter portion 17 is supported by being sandwiched between the upper end surface 10 and the step 19.
Are formed so as not to interfere with the threaded end of the external thread 11 of the outer tube 4.

Next, a method of connecting the upper connecting pipe 1 and the lower connecting pipe 2 will be described. First, when the upper connecting pipe 1 is not connected, the inner pipes 7 and 8 of the lower connecting pipe 2 are held in a state of protruding from the upper end surface 10 of the outer pipe 4. The inner tubes 7 and 8 projecting into the fitting holes of the enlarged diameter portion 17 of the spacer 16 are fitted, and the lower end of the enlarged diameter portion 17 is brought into contact with the upper end surface 10 of the outer tube 4. next,
When the upper connecting pipe 1 is suspended above the lower connecting pipe 2, the inner pipes 5 and 6 in the upper connecting pipe 1 are lowered to a position protruding from the lower end surface 12 of the outer pipe 3. This is due to the structure in which the holders (not shown) of the inner tubes 5 and 6 abut the not-shown steps formed in the outer tube 3. The protruding inner tubes 5 and 6 are fitted into the fitting holes on the reduced diameter portion 18 side of the spacer 16 to bring the outer tube 3 closer to the outer tube 4 side. The enlarged diameter portion 17 and the reduced diameter portion 18 of the spacer 16 are inserted into the inner hole 14 and the small inner hole 15 of the outer tube 3, and the inner screw 13 of the outer tube 3 is turned by turning the outer tube 3. Screw into 11. Also, the enlarged diameter portion 17 of the spacer 16
As described above, the step 19 of the outer tube 3 and the upper end surface 1 of the outer tube 4
The outer tube 3 is screwed until it is clamped between zero. As described above, the upper connecting pipe 1 and the lower connecting pipe 2 are connected via the spacer 16, and the inner pipes 5 and 6 of the upper connecting pipe 1 and the lower connecting pipe 2 via the communication holes 20 and 21 of the spacer 16. The pipes 7 and 8 communicate with each other. Hereinafter, by repeating the same connection method, a connection connecting pipe having a desired length can be formed.

As shown in FIG. 2, the connecting pipe 1 of the present embodiment
In the case of (2), since the inner pipes 5 (7) and 6 (8) are configured to be housed in the inner space inside the outer pipe 3 (4), a large number of inner pipes are necessary for injecting the chemical. It is possible to dispose while securing a sufficient flow passage area. Further, the inner tubes 5, 6 and the like can be easily held, and can be easily and inexpensively implemented.

FIG. 4 shows an outline of a state in which the connecting pipe 100 of the present embodiment is disposed in the ground 22. The connection connection pipe 100 is inserted while being connected to a hole in the ground 22. In the inner pipes 5 (7) and 6 (8), a chemical solution is placed in a pipe 2
By injecting from 3 and 24, the chemical is ejected into the ground 22 as shown by the arrow and supplied.

FIG. 3 shows another embodiment of the present invention. In the figure, components having the same reference numerals as those in FIG. 1 indicate the same components or components having the same functions, and the description thereof will be omitted. A locking portion 25 is formed on the upper end surface 10 side of the outer tube 4 of the lower connecting tube 2. On the other hand, a locking portion 26 that engages with the locking portion 25 is formed on the lower end side of the enlarged diameter portion 17 of the spacer 16 in the drawing. The spacer 16 is fixed to the outer tube 4 by the engagement of the locking portions 25 and 26. Therefore, when the upper connecting pipe 1 is screwed onto the lower connecting pipe 2 while being screwed, the rotation of the spacer 16 is restricted. Therefore, the screwing operation of the upper connecting pipe 1 is performed easily and quickly, and the inner pipes 5, 6, 7, 8 and the like are not twisted, so that the connection between the upper and lower connecting pipes 1 and 2 can be established. It is done reliably.

In the above description, the two inner tubes 5
The case where (7) and 6 (8) are used has been described, but of course the present invention is not limited to this. In addition, inner pipe 5 (7),
The shape of 6 (8) is not limited to the illustrated one.
Further, the inner tubes 5 (7) and 6 (8) are not limited to those for injecting a chemical solution,
As described above, an electric circuit diagram may be used. Further, the shape of the locking portions 25 and 26 may be a structure that restricts rotation when both are engaged, for example, a clutch claw type, and other fitting mechanisms may be applied.

[0018]

According to the present invention, the following remarkable effects are obtained. 1) Since the non-concentric inner tube is screwed to the outer tube while being connected and held via the spacer,
Connection of the connecting pipe is performed quickly and reliably. 2) Handling is extremely easy because the pipe connection is made by screwing. 3) By adopting a structure in which the spacer is fixed to the outer tube on the fixed side, the screw connection operation can be performed more easily, quickly and reliably. Also, no twisting of the inner tube or the like occurs during connection. 4) Since the inner pipes are arranged non-concentrically within the outer pipes, a sufficient flow passage area for a chemical solution or the like can be obtained even when a large number of inner pipes are provided. 5) Even if a large number of inner pipes are provided, it is sufficient to provide a spacer corresponding to the number of the inner pipes, and the connecting operation of the connecting pipes is easily performed regardless of the number of the inner pipes. 6) The manufacturing cost can be reduced as compared with the conventional flange joint.

[Brief description of the drawings]

FIG. 1 is an axial sectional view of an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line DD of FIG. 1;

FIG. 3 is an axial sectional view of another embodiment of the present invention.

FIG. 4 is a schematic axial sectional view showing a state where the embodiment is applied to the ground.

FIG. 5 is a cross-sectional view showing an inner pipe structure of a conventional concentric connecting pipe.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 upper connecting pipe 2 lower connecting pipe 3 upper outer pipe (outer pipe) 4 lower outer pipe (outer pipe) 5 first upper inner pipe (inner pipe) 6 second upper inner pipe (inner pipe) 7 first Lower inner pipe (inner pipe) 8 Second lower inner pipe (inner pipe) 9 Holder 10 Upper end surface 11 Outer thread 12 Lower end face 13 Inner thread 14 Inner hole 15 Small inner hole 16 Spacer 17 Large diameter portion 18 Reduced diameter portion 19 step 20 communication hole 21 communication hole 22 ground 23 pipe 24 pipe 25 locking part 26 locking part 100 connecting connecting pipe

Continuing from the front page (72) Naoki Yamamoto, Inventor Nippon Construction Corporation, 8-14-14 Ginza, Chuo-ku, Tokyo (72) Takao Yokohata 1-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Toho Underground Construction Machinery (56) References JP-A-57-96119 (JP, A) JP-A 55-94988 (JP, U) JP-A 54-177103 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 3/12 E21B 17/02-17/08 E21B 17/18 F16L 37/00-39/04

Claims (2)

(57) [Claims] 1. A connection method for connecting interconnecting pipes each having an outer pipe and a plurality of inner pipes disposed non-concentrically inside the outer pipe, wherein the inner pipe is fitted into a fitting hole of a spacer. Along with
A method for connecting non-concentric multiple pipes, wherein the spacer is sandwiched between both pipes while the upstream side pipe and the downstream side pipe are screwed together. 2. The method according to claim 1, wherein the spacer is fixed to the outer tube of the connecting tube on the side not to be screwed.