JPS5840115Y2 - Double tube outer tube structure for drug injection - Google Patents

Description

[Detailed explanation of the invention] This invention is a double pipe that is inserted into a drilled hole to inject chemicals when injecting chemicals used in ground improvement work, etc., and an inner pipe equipped with a seal packer. The present invention relates to an outer tube structure comprising an outer tube, and the outer tube is equipped with a flexible membrane having a plurality of injection holes and injection slits attached to the outer tube. This invention relates to an outer tube structure of a double tube for injecting chemical liquids, in which grooves are cut so as to define independent sections, so that it can be easily destroyed during so-called post-burying construction.

As is well known, ground improvement work and the like are commonly carried out in civil engineering construction work, and the so-called chemical injection method has been adopted for this work due to its various advantages.

In response to the recent demand for deep chemical injection, various effective methods have been developed and adopted for drug distribution injection methods, one of which is the strainer injection method.

That is, as shown in FIG. 1, the chemical injection tube 1 used in the strainer injection method is equipped with a metal inner tube 2 as appropriate, and the cup type seal packer is equipped with a double inner tube 2 between the packers 3 and 3.
A predetermined number of ejection holes 4, 4, .

The spout hole 4 of the inner tube 2 is inserted into the outer tube 5 made of PVC into which the inner tube 2 can be inserted and pulled out.

Nozzle holes 6, 6... in the parts corresponding to 4...
A predetermined number of holes are drilled therein, and slits 7 for dispensing the chemical solution are formed on the outer surface thereof in correspondence with the nozzle holes 6, 6, . . . .

A cylindrical flexible membrane 8 made of vinyl chloride or the like having a large number of horizontal holes 7 .

Therefore, when the outer tube 5 is inserted into a predetermined ground (not shown), the inner tube 2 is inserted and set into the outer tube 5, and a predetermined chemical solution is force-fed into the inner tube 2. Spout hole 4,
4. The chemical liquid spews out from the packer 3, 3...
. . . to give a sealing effect to the outer tube 5, and the flexible membrane 8 is ejected from the ejection holes 6, 6, .
Construction is carried out by injecting a chemical into the ground through the slits 7, 7, . . . and repeating the process of raising the inner tube 2 relative to the outer tube 5.

Through this process, after construction, the flexible membrane 8 is removed during ground transportation.
The outer tube 5 is left behind, in a so-called buried state.

However, generally after chemical injection work, the next stage of construction is often carried out using the chemical injection work as foundation work, for example,
When shield work is carried out, the shield may cross-pierce through the remaining outer pipe and backfill mortar, and in such cases, there is a drawback that it is extremely difficult to crush and cut the outer pipe because it is underground. Ta.

Also, compared to when the outer tube is a metal tube, if the outer tube is made of a synthetic resin tube such as PVC, it will not cause damage to the shield cutter or will cling to the cutter, resulting in poor crushing efficiency.
Therefore, this becomes an impediment to subsequent construction work, and has the disadvantage that the advantages of the strainer construction method described above become negative.

The purpose of this invention was to take into account the problem of the outer tube of the double-pipe for chemical injection used in the strainer injection method based on the conventional technology, and to carve grooves on the side surface of the outer tube so as not to cause any hindrance to injection. Moreover, the present invention aims to provide an excellent outer pipe structure of a double-pipe for chemical liquid injection based on a rational design, although it has an extremely simple structure, in which a weakly stressed part is formed that is likely to cause repeated fracture in the remaining ground. It is something.

The structure of this invention in accordance with the above purpose is such that the chemical solution fed through the inner tube is ejected from the injection hole of the inner tube and the injection hole of the outer tube via the packer seal, causing the flexible membrane on the outside of the outer tube to bulge. When performing underground work such as shielding with the outer pipe injected into the ground through the slit and left in the ground for chemical injection and filled with mortar, etc., the crushing stress will be applied when the outer pipe is crushed. Concentrates in the groove of the outer tube, and the outer tube is crushed and divided by the groove block through the groove, and in the case of an outer tube made of foamed PVC, etc., it is more likely to be crushed, and it can easily penetrate the intersection. The gist of this is to make it possible to do this.

Next, an embodiment of this invention will be described below based on the drawings from FIG. 2 onwards.

Note that the same parts as those in the embodiment shown in FIG. 1 will be explained using the same reference numerals.

In the embodiment shown in Fig. 2, 5' is the outer pipe of the double pipe for chemical injection used in the strainer injection method, and inside it is the inner pipe 2 with a packer as in the case of Fig. 1. It is made of PVC and can be attached and detached as required, and has a predetermined wall thickness, a predetermined diameter, and a unit length so that it can be connected as appropriate.

As in the previous aspect, a plurality of chemical liquid ejection holes 6, 6, . . . are bored in each block at predetermined intervals in the axial direction.
A flexible vinyl chloride film 8 equipped with 7... is wound with its upper and lower ends adhered with a fixing agent.

Therefore, over the entire length of the outer tube 5', ring-shaped grooves 10, 10, . ... is carved in a ring at a design depth that is not far from the inside.

In the above configuration, when the outer pipe 5' is inserted into a hole pre-bored in the ground (not shown) and inserted into the inner pipe 2 attached to the seal packer 3 as described above, and the chemical solution is injected into a predetermined position, the above-mentioned As in the conventional embodiment, the chemical solution is applied to the packer 3, 3.
Inner pipe 2 ejects through ``JL 4, 4...''
. . . passes through the jet holes 6, 6, . . . of the outer tube 5',
The flexible membrane 8 is bulged out and the chemical solution is squirted into the ground from its slits 7.7, and the chemical injection is repeated as the inner tube 2 rises, thereby carrying out strainer injection as before. After the strainer is injected, mortar is filled inside and outside the outer pipe 5' in the drilled hole to complete the construction.However, after this construction, shield work will cross over the outer pipe 5' as the next stage of construction. When this is done, the crushing stress of a cutter (not shown) during the shielding work is applied to the outer tube 5', and therefore, in the outer tube 5', the wall thickness of the ring-shaped groove 10 is made thinner. The lateral crushing stress concentrates very directly on the thin-walled portion, and as a result, the outer tube 5' is broken into a ring shape and crushed together with its inner and outer filling mortar (not shown).

In this embodiment, the ejection holes are 6°6... as shown in the figure.
... is bored in the tube wall 9 between the ring grooves 10 and 10, and because the ring grooves 10 and 10 are not in communication with each other, the short path of the chemical liquid on the side surface 9 of the outer tube 5' is Does not occur.

Further, in the embodiment shown in FIG. 3, the outer surface 9 of the tube wall of the outer tube 5''
A spiral groove 10' is carved in the spiral groove 10', and after the groove 10' is formed, a dam 11.11 of adhesive material is welded or glued to prevent a short path between the spiral grooves 10'.・
This embodiment is substantially the same as the embodiment described above, in that a vertical groove 10'' is provided not far from the spiral groove 10' to facilitate formation of blocks during crushing.

In this embodiment, the slits 7°7...
. . . desirably does not overlap the vertical groove 10''.

Further, the vertical groove 10'' may be formed on the inner surface or may be omitted.

In the embodiment shown in FIG. 4, the ring groove 10"'
This is an embodiment in which the outer tube 5'' is provided as a ring on the inner surface 9' of the tube wall of the outer tube 5'', and substantially the same operation and effect as in the previous two embodiments is achieved.

It goes without saying that the embodiments of this invention are not limited to the above-mentioned embodiments, and include various designs as long as the outer tube is crushed.

That is, for example, if the outer tube is made of a foamed PVC tube, not only will it be easier to crush without having to cut grooves on the outer tube, but it will also be lighter in weight. The effect is further promoted in the embodiment in which grooves are carved as in the various embodiments.

As mentioned above, according to this invention, in the outer tube structure of the double tube for chemical injection, the seal packer can be attached and detached at will, and a flexible membrane equipped with many slits is added on the outside of the ejection hole. Furthermore, by carving a groove that substantially defines the side surface of the outer tube without intersecting the nozzle hole, basically after the strainer injection work, etc. Even if later work such as shielding is carried out on the outer pipe left in the ground in a so-called buried manner, the breaking stress of the cutter etc. acts intensively on the thin walled part of the groove of the outer pipe. Therefore, the outer tube is easily divided and crushed and does not stick together, which has the excellent effect of allowing the later construction work to be carried out smoothly.

In addition, since it can be easily broken into blocks in this way, it has the advantage that even metal outer tubes can be broken, and it can be applied not only to synthetic resin tubes.

Furthermore, when the groove is a ring-shaped groove or the like, the upper and lower ends of the flexible membrane can be firmly fixed to the outer tube by using the groove.

In addition, by forming grooves on the outer tube, not only is it possible to reduce the weight by that amount, but after injecting chemicals through the stress concentration weak points,
There is also the secondary benefit of being able to crush the material in advance by supplying high-pressure air and then inject mortar into the material.

Since the grooves are carved so as to partition the side surfaces of the outer tube independently from each other as described above, there is no risk of a short pass through the grooves during drug injection, and therefore, there is no problem with drug injection. There is also the advantage of being able to do it without having to do it.

Furthermore, by making the pipe body made of foamed PVC or the like, there are advantages in that crushing can be carried out more effectively and weight reduction can also be attempted.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the chemical liquid injection tube structure based on the conventional technology, Figure 2
The following figures are explanatory diagrams of the embodiment of this invention, and Figure 2 is 1
This is a structural explanatory diagram of an embodiment, and FIGS. 3 and 4 are structural explanatory diagrams of other embodiments. 3... Seal packer, 2... Inner pipe,
9,9'...Tube wall, 6...Blowout hole, 7
...Slit, 8...Flexible membrane, 5'. 5//, 5///...Outer tube, 10.10', 1
0'', 10'''...Groove.

Claims (1)

[Scope of utility model registration request] For chemical injection, it has a removable inner tube equipped with a seal packer, has multiple injection holes in the tube wall, and has a flexible membrane with many injection slits on the outer surface. In the outer tube structure of the double tube, the outer tube is provided with grooves carved on the tube side surface thereof so as to define the tube surfaces substantially independently of each other so as not to intersect with the nozzle holes. A double-tube outer tube structure for drug injection.