JP2719264B2 - Double steel pipe for propulsion - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double steel pipe for propulsion, such as a gas pipe, having a double pipe structure, which is suitable for a propulsion method of burying the ground by propelling the ground.

[0002]

2. Description of the Related Art For example, a double steel pipe in which concrete or the like is poured between an inner pipe and an outer pipe is used as a pipe buried in the soil to send high-pressure gas, in order to maintain the strength of the pipe. May be used. When burying this double-walled steel pipe in the soil, instead of digging and burying a long and narrow groove along the path to be buried from the ground, digging a predetermined shaft, the side wall of this shaft A so-called propulsion method of burying a double steel pipe by propelling it in the longitudinal direction may be adopted.

FIG. 5 is a side view (a) and a sectional view (b) showing an example of a conventional double steel pipe for propulsion used when adopting the above-mentioned propulsion method. This double steel pipe 31
Has, as its basic structure, an inner pipe 33 and an outer pipe 35, and a concrete 37 filling the space between the inner pipe 33 and the outer pipe 35.
Consists of Here, the front end 33a and the rear end 33b of the inner pipe 33 are not covered with the concrete 37 and are exposed.

[0004] A number of such double steel pipes 31 are prepared,
Propulsion into the ground in the direction indicated by the arrow in the figure,
The rear end face 33d of the already promoted double steel pipe 31 and the front end face 33c of the new double steel pipe 31 are brought into contact with each other and welded. To the rear end face 35b of the outer pipe 35 of the double steel pipe 31 already propelled and the outer pipe 5 of the new double steel pipe 31.
Of the inner pipe 33 of the new double steel pipe 31 and the rear end face 35 of the outer pipe 35.
A thrust is applied to b to propel it in the direction of the arrow. By repeating this many times, the double steel pipes 31 connected to each other are buried in the soil.

[0005]

When the conventional double steel pipe as described above is used, the rear end face 3 of the inner pipe 33 is propelled by the propulsion.
For example, 3d is bent or scratched, and a step of shaping the rear end face 33d before welding with the inner pipe of the next double steel pipe is required. Further, the propulsion causes internal stress in the inner pipe 33, and the inner pipe 33 is buried in the soil and used during use.
For example, there was a possibility that pinholes, cracks and the like may occur in No. 3.

The present invention has been made in view of the above circumstances, and provides a double steel pipe for propulsion which does not require a step of shaping the rear end face of the inner pipe and which can be propelled without generating internal stress in the inner pipe. With the goal.

[0007]

In order to achieve the above object, a double steel pipe for propulsion according to the present invention comprises an inner pipe and an outer periphery of the inner pipe such that both ends of the inner pipe are exposed. And an outer tube that slides between the intermediate members. Here, the inner pipe and the outer pipe are, for example, steel pipes, and the intermediate material is, for example, concrete, mortar, or the like.

Preferably, a grout hose insertion hole extending in the longitudinal direction of the buried double steel pipe is provided inside the intermediate member. Further, it is preferable to provide a check valve on one end side of the outer tube, which allows a one-way outflow from the inside of the outer tube to the outside. Further, it is preferable to provide a lubricating layer between the outer tube and the intermediate member.

Here, the lubricating layer may be a lubricant such as a lubricating oil, for example, or a chemical compound such as polypropylene, which reduces the sliding resistance between the outer tube and the intermediate material. It may be a tubular article formed of a resin, metal, or the like into a tubular shape, or may be both a lubricant and a tubular article. When a tubular article is provided, the tubular article may be fixed to the inner wall of the outer tube and slide with the outer tube relative to the intermediate member, or may be fixed to the intermediate member and the outer tube May be configured to slide on this tubular object, or without being fixed to either the outer tube or the intermediate material,
When the outer tube is slid with respect to the intermediate member, the outer tube may be configured to slide with respect to both the outer tube and the intermediate member.

[0010] Further, a double steel for propulsion is provided at one end of the outer tube.
It is also preferable to provide a guide member for guiding one end of the outer tube to the other end of the adjacent outer tube when connecting the tubes .

[0011]

The double steel pipe for propulsion of the present invention has a structure in which the intermediate member slides between the outer pipe and the outer pipe. By applying a thrust only to the outer pipe, the rear end face of the inner pipe is damaged. This double steel pipe for propulsion can be buried in the soil by using the propulsion method without attaching it and without causing internal stress in the inner pipe. Cracks and the like are prevented from occurring, and highly reliable construction is possible.

When this double steel pipe for propulsion is to be propelled into the soil, for example, after welding is performed by bringing the inner pipe into contact with each other,
A method is adopted in which the outer tubes are brought into contact with each other and thrust is applied to the outer tubes to propel the whole. In addition, by providing the above-described guide member to the double steel pipe for propulsion, when the outer pipe is slid, an error in displacement between the outer pipes is absorbed, so that the end faces of the outer pipe can be accurately positioned. Can be abutted.

A lubricating layer is provided between the outer tube and the intermediate material,
As a result, the sliding resistance between the outer tube and the intermediate member is reduced, so that the outer tube can reliably slide on the intermediate member. Further, by providing a grout hose insertion hole in the above-described double steel pipe for propulsion, connecting the inner pipes by welding, for example, and then connecting the grout hoses to each other, a plurality of double steel pipes for propulsion are provided. Can be filled into the ground by the propulsion method and then a filler such as cement milk can be poured into the connected grout hose to fill the space between the inner and outer pipes of the double steel pipe for propulsion connected to each other In this case, the connection between the inner pipe and the outer pipe is also filled with cement milk or the like at the connection portion of the double steel pipe for propulsion, and the buried pipe becomes stronger.

At this time, if the above-mentioned check valve is provided at one end side of the outer pipe, water, earth and sand, etc. hardly enter between the inner pipe and the outer pipe during propulsion. However, when the filler is filled, the water, earth and sand, etc. are unilaterally pushed out of the outer tube by the filling pressure, and the filler is filled in the space sandwiched between the inner tube and the outer tube. Will be enough. Further, the filler itself flows out of the outer pipe through the check valve, so that the surplus space near the outer wall of the outer pipe is filled with the filler, and the buried pipe becomes stronger.

[0015]

Embodiments of the present invention will be described below. 1 is a side view along a longitudinal direction of a double steel pipe for propulsion according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of the double steel pipe for propulsion shown in FIG. 3 is an enlarged side view of a portion indicated by a circle A in FIG. Here, a double steel pipe for gas propulsion will be described as an example.

FIG. 1 and FIG. 3 show a double steel pipe for propulsion 1 'and a double steel pipe for propulsion 1' in a state where it has already been propelled into the soil and only a part of the rear end projects into the shaft. A new double steel pipe 1 for propulsion connected to the rear end and propelled into the soil together with the double steel pipe 1 'for propulsion is shown. These double steel pipes 1 and 1 'for propulsion have the same structure.

The double steel pipe 1 for propulsion has an inner pipe 2 of about 900 mmφ made of steel pipe and an inner pipe 2 of about 12 mm also made of steel pipe.
It comprises an outer pipe 3 having a diameter of 00 mm and concrete 4 as an intermediate material for filling between the inner pipe 2 and the outer pipe 3. Here, as shown in FIG. 2, an embi tube 5 forming a grout hose insertion hole according to the present invention is embedded in the concrete 4, and a grout hose 6 is inserted through the embi tube 5.

As shown in FIG. 3, a check valve 9 near the front end of the outer tube 3 in the propulsion direction is opened when pushed from inside the tube and closed when pushed from outside the tube.
Is provided. Further, a polypropylene pipe 7 is provided on the outer periphery of the concrete 4, and a lubricant is applied between an inner wall of the outer pipe 3 and an outer wall of the polypropylene pipe 7. Thereby, when the outer tube 3 is pushed in the longitudinal direction, the outer tube 3 slides against the concrete 4.
A guide ring 10 as a guide member according to the present invention is provided at a front end of the outer tube 3 and a stop ring 11 is provided at an inner wall side of a rear end of the outer tube 3.
When the outer tube 3 slides on the concrete 4 and moves forward, the guide ring 10 becomes the outer tube 3 'of the double steel tube 1' for propulsion.
Into the inside from the rear end face 3 c ′ side, and the front end thereof contacts the stop ring 11. At the same time, the front end face 3b of the outer pipe 3 of the propulsion double steel pipe 1 and the propulsion double steel pipe 1 '
Abuts on the rear end face 3c 'of the outer tube 3'. Since the guide ring 10 is provided in this manner, even if there is some misalignment between the outer tubes 3, 3 ', the error is absorbed, and the outer tubes 3, 3' are absorbed.
The 3 'butt touches exactly.

The outer surface 2a of the inner tube 2 is coated with polyethylene. As shown in FIGS. 1 and 3, after the front end face 2b of the inner pipe 2 of the double steel pipe 1 for propulsion and the rear end face 2c 'of the inner pipe 2' of the double steel pipe 1 'for propulsion come into contact with each other, this contact is made. The inner pipe of the contact portion is welded, and after this welding, the welded portion is newly covered with a corrosion-resistant polyethylene tube from the outer surface. FIG.
Fig. 4 is a schematic diagram showing a propulsion method for burying a double steel pipe for propulsion having the structure shown in Figs.

As shown in FIG. 4 (a), it is assumed that the double steel pipe for propulsion 1 'has already been propelled into the soil by the propulsion method and a part of the rear end thereof has protruded into the shaft. For the double steel pipe for propulsion 1 'whose part of this rear end protrudes into the shaft,
A new double steel pipe 1 for propulsion is prepared, and the front end face 2b of the inner pipe 2 and the rear end face 2 'of the double steel pipe 1' for propulsion have already been propelled.
The double steel pipe 1 for propulsion is arranged so that c ′ comes into contact with the pipe (see FIGS. 1 and 3).

Next, as shown in FIG. 4 (b), the rear end face 2c 'of the propulsion double steel pipe 1' and the front end face 2b of the propulsion double steel pipe 1 which are in contact with each other are welded. The later condition is inspected using X-rays, and if this inspection is passed, the weld is covered with a polyethylene tube 20. As described above, the portion of the outer wall 2a of the inner pipe 2 that is hidden by the concrete 4 is also coated with polyethylene.

Next, as shown in FIG. 4 (c), the grout hose 6 is inserted into the grout hose insertion tube 5 shown in FIG. 2 of the propulsion double steel tube 1, 1 '. Connected. However, in this case, about one place that will be finally located near the center by being connected and propelled in a large number, the connected grout hose can be pulled out half by half from the front and the rear in the propulsion direction. , Leave unconnected.

Thereafter, the outer pipe 3 is slid forward with respect to the concrete 4 from the state shown in FIG. 4 (c) to the state shown in FIG. 4 (d), whereby the front end face 3b of the outer pipe 3 is moved. Abuts on the rear end face 3c 'of the outer tube 3'. afterwards,
As shown in FIG. 4 (e), at the rear end of the double steel pipe 1 for propulsion,
A pressing wheel 21 is provided so as to contact only the rear end face 3c of the outer tube 3.
The propulsion hydraulic jack 22 is set so as to press the pressing wheel 21, and a thrust is applied to the outer pipe 3 to transform the propulsion double steel pipe 1 into the propulsion double steel pipe 1 ′ and the propulsion double steel pipe 1 ′. It is propelled into the soil together with the same type of double steel pipe for propulsion connected further forward than 1 '. Here, a not-shown excavation head is attached to the front end of the foremost double steel pipe for propulsion, whereby the propulsion is performed while digging.

After the propulsion through the above-described steps is performed over a large number of propulsion double steel pipes, the grout hose 6
The cement milk is poured into the connection portion (see FIG. 2), and the grout hose is pulled out, for example, so as to be sequentially disposed at the connection portion of the double steel pipe for propulsion. Fill. In this case, when pulling out the grout hose 6 rearward in the propulsion direction, the grout hose insertion tube 5 of the double steel pipe for propulsion arranged at the front end in the propulsion direction is used.
It is preferable to close this opening so that cement milk does not flow out of the opening at the front end. Also, when pulling out the grout hose 6, the tube 5 for inserting the grout hose is used.
It is preferable to pull out the grout hose 6 while pouring the cement milk so that the inside of the grout hose 6 is filled with the cement milk. When the space between the inner tube 2 and the outer tube 3 of the connection portion is filled with the cement milk, the cement milk passes water, earth and sand, etc. between the inner tube 2 and the outer tube 3 via the check valve 9. As a result, the cement milk itself flows out through the check valve and flows out of the outer pipe 3, and the cement milk itself flows out of FIG.
As shown in (f), the outer wall of the outer tube 3 is also covered with cement milk. As a result, the buried pipe becomes stronger, and the settlement of the ground surface can be prevented.

As an example, a gas having a gas pressure of 70 kg / cm ² is passed through the inner pipe of the double steel pipe buried in the soil. Although the double steel pipe for gas propulsion has been described here, it is needless to say that the present invention is not limited to the gas propulsion steel pipe.

[0026]

As described above, the double steel pipe for propulsion of the present invention is provided with the outer pipe that slides between the intermediate pipe and the inner pipe by applying thrust only to the outer pipe. A propulsion method has been realized that does not cause collapse of the end face of the pipe or internal stress in the inner pipe, thereby enabling highly reliable pipe burying.

Here, in the case where the above-mentioned guide member is provided, the error of the positional deviation between the outer tubes is absorbed. Also,
If a lubricant coating is formed between the outer tube and the intermediate material, the sliding resistance of the outer tube against the intermediate material is reduced, and a part of the intermediate is formed on the outer peripheral surface of the intermediate. The provision of the polypropylene tube further reduces the sliding resistance.

Further, by providing the grout hose insertion hole described above, the connecting portion of the double steel pipe for propulsion can be filled with a filler, and if the above-described check valve is provided,
It extrudes water, earth and sand, etc., and the outer wall of the outer tube can be covered with the filler.

[Brief description of the drawings]

FIG. 1 is a side view along a longitudinal direction of a double steel pipe for propulsion according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the double steel pipe for propulsion shown in FIG. 1 as viewed from the right side in FIG.

FIG. 3 is an enlarged side view of a portion indicated by a circle A in FIG. 1;

FIG. 4 is a schematic diagram showing a propulsion method for burying a double steel pipe for propulsion having the structure shown in FIGS.

FIG. 5 is a side view (a) and a cross-sectional view (b) showing an example of a conventional double steel pipe for propulsion used when adopting the propulsion method.

[Explanation of symbols]

1, 1 'double steel pipe for propulsion 2 inner pipe 3 outer pipe 4 concrete 5 embi pipe 7 polypropylene pipe 9 check valve 10 guide ring 11 stop ring

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akitaka Fujita 1-7-7 Suehirocho, Tsurumi-ku, Yokohama-shi Inside the Tokyo Gas Co., Ltd. Pipe Technology Center (72) Inventor Shingo Nagashima 1 Suehirocho, Tsurumi-ku, Yokohama-shi 7-7-7 Tokyo Gas Co., Ltd. Conduit Technology Center (72) Inventor Akira Adachi 3-17-18 Matsunami, Chiba City (72) Inventor Tomoya Fujimoto 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel (72) Inventor Shigeru Morishita 2-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel Corporation

Claims (4)

(57) [Claims] 1. A propulsion device comprising: an inner pipe; an intermediate member that covers an outer periphery of the inner tube so that both ends of the inner tube are exposed; and an outer pipe that slides between the intermediate member. Heavy steel pipe, which is connected to one end of the outer pipe when the double steel pipes for propulsion are connected to each other.
Propulsion double steel pipe characterized by comprising a guide member for guiding the one end portion to the other end of the outer tube next. 2. A propulsion device comprising: an inner tube; an intermediate member covering an outer periphery of the inner tube so that both ends of the inner tube are exposed; and an outer tube sliding between the intermediate member. a heavy steel pipe, propulsion double steel pipe characterized by comprising a lubricating layer between the outer wall and the inner wall of the outer tube of the middle-material. 3. A propulsion device comprising: an inner pipe; an intermediate material covering an outer periphery of the inner pipe so that both ends of the inner pipe are exposed; and an outer pipe sliding between the intermediate material. a heavy steel pipe, the end portion of the outer tube, propulsion double tube check valve is characterized by being provided to allow one - way efflux from the inside toward the outside of the outer tube. 4. A propulsion device comprising: an inner pipe; an intermediate material covering an outer periphery of the inner pipe so that both ends of the inner pipe are exposed; and an outer pipe sliding between the intermediate material. a heavy pipe, inside middle-material, propulsion double tube, characterized by comprising grout hose insertion hole is provided extending in the longitudinal direction of the double pipe for promotion.