JPS6346512Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tube suitable for use in a chemical injection device for civil engineering of a type in which the liquid injection tube is self-propelled.

In civil engineering work such as tunnel or building construction, if the ground is soft, it is hardened over time before work begins to prevent accidents such as cave-ins and to make excavation work easier. It is common practice to inject a chemical with a specific property and harden the ground before excavation work is carried out. Various difficulties have been pointed out in the conventional chemical injection work, but recently, the invention of the present invention has been proposed. A chemical injection device for civil engineering has been developed by a person who has completely solved the problems of the conventional method, and a patent application has already been filed.

That is, as shown in FIG. 1, this device consists of a guide tube A having a flange-like head H or fins F at one end, and a chemical injection tube C having one end sealed S.
The ground G where the chemical solution is to be injected is fixed.
Insert the casing pipe into the borehole B formed in
Cs and seal it using a packer P. If a chemical solution injection machine (not shown) is connected to the rear end of the guide tube A and the chemical solution is press-fitted, the chemical solution injection tube C will expand due to the pressure. The chemical is injected into the deep part of the borehole B when the pressure inside the tube C increases and the seal S is finally ruptured.

However, after repeated experiments with the above device, it was found that the borehole B formed in the ground B
The thickness of the drug injection tube C must be varied depending on the depth of the liquid injection tube, the amount of drug to be injected, and other factors. It has been found that there are cases where the pipe does not break under the injection pressure and ends simply by extending and moving forward through the borehole B.

In this case, since the chemical liquid injection tube is usually made of soft plastic, it is possible to break the seal S part by replacing it with a larger chemical liquid injection machine, but in a chemical liquid injection site such as a tunnel, the space is limited. Due to technical limitations, it is extremely difficult to prepare a large chemical liquid injection machine in addition to the regular one.

On the other hand, if a notch is made in the seal S part, it will easily break even with a normal chemical injection machine, but since pressure is initially applied to the seal S part to extend and advance the chemical liquid injection tube C, it is difficult to break it in this way. However, another problem arises in that the seal S part is torn midway, making it impossible to inject the chemical solution to the desired depth of the borehole B.

Based on the above-mentioned circumstances, the present invention was designed to withstand sufficient pressure during extended self-propulsion, and to easily break the seal part when internal pressure increases after self-propulsion ends. It was designed to provide a tube for use in liquid drug injection devices, and its structure is that it is fitted and fixed in a substantially folded state to a guide tube with a flange-like head etc. at one end, and is press-fitted into the guide tube. In the tube of a chemical liquid injection device for civil engineering, the tube is expanded by the pressure of the fluid, and when the expansion stops, the seal at the tip breaks and the chemical liquid is spouted out. The device is characterized in that a sub-seal portion is provided for a portion that expands or expands due to the pressure of the fluid that is press-fitted, to counteract the expansion or expansion.

Next, an example of an embodiment of the present invention will be described with reference to the drawings.

In Fig. 2, 1 is a tube body formed of relatively soft plastic stick to an appropriate diameter and length, and 2 is a seal portion formed by heat-sealing one tip of the body 1 from above and below in an arc shape. in,
The seal portion 2 closes one end of the main body 1.

Further, reference numeral 3 denotes a sub-seal part 3 formed perpendicularly to the seal part 2 of the main body 1, and the sub-seal part 3 is partially overlapped with the seal part 2 near the center of the seal part 2, and is sealed from above and below. By heat-sealing in a straight line, when a chemical liquid is injected into the main body 1 and the main body 1 expands or expands due to the pressure, the heat-sealed sub-seal portion 3 acts to prevent this. 1 to 4 above constitute an example of the present invention.

Note that the length of the sub-seal part 3 may or may not exceed the connecting line between both ends 2a and 2b of the seal part 2, but as will be described later, Controls the area that ruptures when a chemical solution is injected into 1.

Thus, the tube of the present invention constructed as described above is fitted into the guide tube A in a substantially folded state similar to that shown in FIG. If a chemical solution is pressurized from a chemical solution injection machine (not shown) connected to the rear end of the guide tube A, the pressure of the chemical solution increases at the tip of the guide tube A, and the folded part is restored by the head H and fin F while boring is performed. Although it will extend and move forward in the hole B, under this principle and the pressure during this extension and move forward, not only both seal portions 2 and 3 but also any part of the main body will not break, as is the case with conventional products.

If the main body 1 extends over its entire length or stops elongating because its tip gets caught on a convex part of the inner wall of the borehole B, the pressure inside the main body 1 is reduced by the continued press-fitting of the agent. The pressure gradually increases and acts uniformly on the main body 1 in the circumferential direction, but at the tip where the seal part 2 and sub-seal part 3 are formed, the seal part expands or expands due to the pressure and peels off. It works particularly strongly at both ends 2a, 2b of the seal part 2 and the rear end 3a of the sub-seal part 3, and eventually those parts cannot resist the pressure and break.

At this time, the sub seal portion 3 is attached to both ends of the seal portion 2.
If it is longer than the connecting line between the ends 2a and 2b of the seal part 2, the peeling force will act exclusively on the rear end 3a, causing that part to break.If the sub-seal part 3 is shorter than the connecting line between the ends 2a and 2b of the seal part 2, Since the curved surface formed by the sub-seal portion 3 concentrates the peeling force on both end portions 2a and 2b, the breakage occurs only in those portions.

That is, the chemical liquid injection device for civil engineering that employs the tube of the present invention can always spray the chemical liquid from the tip of the tube of the present invention and inject it into the ground.
If you adjust the length of the tube of this invention in advance,
It also becomes possible to inject the drug to a desired depth in the ground.

As described above, the present invention is extremely practical as a tube for use in a chemical injection device for civil engineering in which a chemical liquid is pressurized into a guide tube, the tube is extended and moved forward by the pressure, and then broken and the chemical liquid is injected. expensive.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of an example of a device using the tube of the present invention, FIG. 2 is a side view of an example of the tube of the present invention,
FIG. 3 is also a front view. 1...Main body, 2...Seal part, 3...Sub-seal part.

Claims (1)

[Scope of utility model registration request] It is fitted and fixed in a substantially folded state to a guide tube with a flange-shaped head etc. at one end, and is expanded by the pressure of the fluid that is press-fitted into the guide tube, and when the expansion stops, the tip is sealed. In a tube of a chemical liquid injection device for civil engineering in which a part etc. is ruptured and a chemical liquid is spouted out, the tube expands or expands due to the pressure of the fluid that is press-fitted near the sealing part. A tube used in a chemical injection device for civil engineering, characterized by having a sub-seal part.