JP2701727B2 - Double steel pipe for propulsion method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for digging a steel pipe in a soil at a desired position where the ground portion at the desired position cannot be cut or undesired. The present invention relates to a double steel pipe for a propulsion method used in a propulsion method in which a steel pipe is propelled and laid from a separated position to the above-mentioned position. In addition, propulsion means moving the soil in the longitudinal direction of the steel pipe.

[0002]

2. Description of the Related Art Conventionally, when laying a pipe in the soil across a road or the like, a method of cutting off a road while blocking traffic and laying a pipe has been adopted. However, this method requires only an appropriate detour to cut off traffic, but if there is no detour, there is a drawback that it greatly affects local traffic.

Therefore, as a method of laying a pipe in such a case, a propulsion method (hereinafter, referred to as "prior art 1") disclosed in JP-A-59-210191 and JP-A-59-170399 is disclosed.
Is often adopted. The feature of this prior art 1 construction method is that pits are dug at both ends of the construction area slightly away from the road, double steel pipes to be laid in one of the pits are placed horizontally, and jacks are used from one end of the construction area. To complete the laying by propelling the soil toward the other end. According to this method, there is no need to block traffic on the road.

However, in the propulsion method of the prior art 1, since only the inner pipe (main pipe) of the double steel pipe is pushed and jacked, the inner pipe and the outer pipe have an adhesive force that does not separate. It is necessary to have. That is, in the double steel pipe used in the method of Prior Art 1, it is assumed that there is no displacement between the inner pipe anticorrosion layer and the filler during propulsion.

FIG. 7 is a partial sectional view showing an example of a conventional double steel pipe for a propulsion method. As shown in FIG. 7, a conventional double steel pipe for a propulsion method includes an inner pipe (main pipe) 1, an outer pipe 4, an asphalt layer 9 coated on the outer peripheral surface of the inner pipe 1, and an asphalt layer 9. A filler material 5 made of cement mortar for protecting the inner tube 1 filled between the outer tube 4 and the inner tube 1 from corrosion and damage during propulsion is integrated. In such a double steel pipe for a propulsion method, the adhesiveness between the filler 5 and the asphalt layer 9 is ensured by the roughness of the asphalt surface.

[0006]

However, since the above-mentioned asphalt has a problem that a desired effect cannot be obtained in the anticorrosion action, it is necessary to use a material which can expect a more reliable anticorrosion effect. As such a material, we studied a resin-based anticorrosion layer. However, since the resin-based anticorrosion layer has a smaller outer surface roughness than asphalt, the adhesion between the filler and the anticorrosion layer is reduced, that is, the adhesion between the inner pipe and the outer pipe is reduced, and during propulsion. There is a problem that the displacement of both tubes occurs.

Accordingly, an object of the present invention is to use a resin-based anticorrosion layer, improve the adhesiveness between the anticorrosion layer and the filler, and improve the adhesion between the inner tube and the outer tube as compared with the prior art. An object of the present invention is to provide a double steel pipe for a propulsion method capable of preventing displacement of both pipes and improving laying work efficiency.

[0008]

The first invention of the present application is directed to a double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe. At
The anticorrosion layer comprises a layer made of a thermoplastic resin coated on the outer peripheral surface of the inner tube, and a rope made of a thermoplastic resin wound spirally around the outer peripheral surface of the layer and fixed by heat fusion. It is characterized by becoming.

A second invention of the present application is directed to a double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is A layer of a thermoplastic resin coated on the outer peripheral surface of the inner tube,
It is characterized by comprising a ring-shaped intermittent shrink tube having heat shrinkability wound around the outer peripheral surface of the layer and fixed by heat fusion.

The third invention of the present application is directed to a double steel pipe for a propulsion method, comprising: an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is A layer of a thermoplastic resin coated on the outer peripheral surface of the inner tube,
A wire rope wound around the outer peripheral surface of the layer, and a heat shrinkable wound around the outer peripheral surface of the layer over the wire rope and fixed to the outer peripheral surface of the layer together with the wire rope by heat fusion. And a ring-shaped intermittent shrink tube.

A fourth invention of the present application is directed to a double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is A layer of a thermoplastic resin coated on the outer peripheral surface of the inner tube,
It is characterized by comprising an outer layer made of a thermoplastic resin coated on the outer peripheral surface of the layer, and a wire rope spirally wound around the outer peripheral surface of the outer layer and fixed by heat fusion.

A fifth invention of the present application is directed to a double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is And a layer made of a belt-shaped thermoplastic resin wound and covered in a spiral shape so that an end thereof overlaps the outer peripheral surface of the inner tube.

In the second, third or fifth invention of the present application,
A thermosetting resin may be used instead of the thermoplastic resin.

In the second or third aspect of the present invention, a shrink net having heat shrinkability may be used instead of the shrink tube.

[0015]

Hereinafter, the reason why the present invention is configured as described above will be described. The most widely used material for the currently used anticorrosion layer is a polymeric thermoplastic resin or thermosetting resin. This resin material is used as an anticorrosion layer, and a filler is filled between the inner pipe (main pipe) and the outer pipe to form a double pipe.

In the first invention of the present application, since the rope made of the thermoplastic resin is spirally wound around the outer peripheral surface of the layer made of the thermoplastic resin and fixed by heat fusion, the adhesion between the anticorrosion layer and the filler is improved. improves. At this time, since the thickness of the anticorrosion layer does not fall below the thickness at the time of manufacture, it can be generally used under the conditions at the time of manufacturing a conventional anticorrosion tube.

In the second invention of the present application, a ring-shaped intermittent shrink tube or shrink net having heat shrinkability is wound and fixed on the outer peripheral surface of a layer made of a thermoplastic resin coated on the outer peripheral surface of the inner tube. Thereby, the adhesion between the anticorrosion layer and the filler is improved. In the present invention, a desired effect can be obtained even if a thermosetting resin is used instead of the thermoplastic resin.

In the third invention of the present application, a wire rope is wound around an outer peripheral surface of a layer made of a thermoplastic resin coated on an outer peripheral surface of an inner tube, and a ring-shaped intermittent shrink tube or shrink net having heat shrinkability is provided. By fixing the wire rope, the adhesion between the anticorrosion layer and the filler is improved. In the present invention, a desired effect can be obtained even if a thermosetting resin is used instead of the thermoplastic resin.

In the fourth invention of the present application, the outer peripheral surface of the thermoplastic resin layer coated on the outer peripheral surface of the inner tube is coated with an outer layer made of the same material (thermoplastic resin) as the above-mentioned layer, and the outer peripheral surface of the outer layer is formed. After the wire rope is wound around the surface, the wire rope is heated by current conduction and fused, or the heated wire rope is spirally wound and fixed by bonding, so that the adhesiveness between the anticorrosion layer and the filler is fixed. Is improved.

In the fifth invention of the present application, the adhesiveness between the anticorrosion layer and the filler is improved by fixing the inner pipe with a strip-shaped thermoplastic resin wound and covered in a spiral shape so that the end overlaps the outer peripheral surface of the inner pipe. improves. In the present invention,
A desired effect can be obtained even if a thermosetting resin is used in place of the thermoplastic resin.

Even if the inner pipe of the double steel pipe according to the first to fifth aspects of the present invention is pushed and pushed with a jack or the like, no displacement occurs between the anticorrosion layer and the filler during the propulsion. And the outer tube do not shift.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described based on embodiments shown in the drawings.

Embodiment 1 FIG. 1 is a side view showing one embodiment of an inner pipe and an anticorrosion layer constituting a double steel pipe for a propulsion method according to the present invention, and FIG. 2 is formed by using the steel pipe shown in FIG. It is a fragmentary sectional view showing a 1st embodiment of the double steel pipe for propulsion methods of the present invention. In this embodiment, a thermoplastic resin is used, and polyethylene is used. Figures 1 and 2
As shown in the figure, the double-walled steel pipe is spirally wound around the inner pipe 1, the polyethylene layer 2 coated on the outer peripheral face of the inner pipe 1, and the outer peripheral face of the polyethylene layer 2, and heated and fused by a gas burner or the like. A rope 3 made of polyethylene, a cement mortar 5 as a filler, and an outer pipe 4. The diameter of the polyethylene rope 3 is the polyethylene layer 2
And the distance between the polyethylene ropes 3 was 0.5 to 2 D with respect to the diameter (D) of the inner tube 1.

Embodiment 2 FIG. 3 is a partial sectional view showing a second embodiment of a double steel pipe for a propulsion method according to the present invention. FIG.
As shown in the figure, the double steel pipe has an inner pipe 1, a polyethylene layer 2 coated on the outer peripheral surface of the inner pipe 1, and a heat-shrinkable ring intermittently wound around the outer peripheral surface of the polyethylene layer 2. It comprises a shrink tube 7, a cement mortar 5, and an outer tube 4. The shrink tube 7 is made of a resin material, and the distance between the shrink tube 7 and the inner tube 1 diameter (D)
The width was 0.5 to 2D and the width was 0.1 to 0.2D. In this embodiment, a desired effect can be obtained by using either polyethylene or a thermosetting resin polyurethane as the layer 2. Although not shown, a desired effect can be obtained by using a shrink net instead of the shrink tube.

Embodiment 3 FIG. 4 is a partial sectional view showing a third embodiment of a double steel pipe for a propulsion method according to the present invention. FIG.
As shown in the figure, the double steel pipe comprises an inner pipe 1, a polyethylene layer 2 coated on the outer peripheral surface of the inner pipe 1, a steel wire rope 8 wound on the outer peripheral face of the polyethylene layer 2, and a wire. An intermittently wound heat-shrinkable ring-shaped shrink tube 7 that covers and fixes the rope 8, a cement mortar 5, and an outer tube 4. The diameter of the wire rope 8 was 2 to 3 times the thickness of the polyethylene layer 2, the interval was 0.5 to 2D relative to the diameter (D) of the inner tube 1, and the width of the shrink tube 7 was 0.1 to 0.2D. In this embodiment, a desired effect can be obtained by using either polyethylene or polyurethane as the layer 2. Although not shown, a desired effect can be obtained by using a shrink net instead of the shrink tube.

Embodiment 4 FIG. 5 is a partial sectional view showing a fourth embodiment of a double steel pipe for a propulsion method according to the present invention. FIG.
As shown in the figure, the double steel pipe has an inner pipe 1, a polyethylene layer 2 coated on the outer peripheral surface of the inner pipe 1, and a protective layer (outer layer) 6 made of polyethylene coated on the outer peripheral face of the polyethylene layer 2. And a wire rope 8 wound around the outer peripheral surface of the outer layer 6, a cement mortar 5, and an outer tube 4. In this embodiment, a desired effect can be obtained by using either polyethylene or polyurethane. However, the same material is used for the layer 2 and the outer layer 6.

Embodiment 5 FIG. 6 is a partial sectional view showing a fifth embodiment of a double steel pipe for a propulsion method according to the present invention. FIG.
As shown in the figure, the double steel pipe has an inner pipe 1, a strip-shaped polyethylene layer 2 wound and coated in a spiral shape so that an end thereof overlaps the outer peripheral surface of the inner pipe 1, a cement mortar 5,
It consists of an outer tube 4. In this embodiment, a desired effect can be obtained by using either polyethylene or polyurethane as the layer 2.

[0028]

As described above, according to the present invention, high corrosion resistance can be obtained because a polymer resin having an excellent anticorrosion effect is used, and irregularities can be formed without damaging the anticorrosion layer. Even though such a polymer resin is used, the adhesion between the anticorrosion layer and the filler is so good that the inner pipe and the outer pipe do not shift during propulsion despite the use of such a polymer resin. The work efficiency of the construction is improved, and thus an industrially useful effect is provided.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of an inner pipe and an anticorrosion layer constituting a double steel pipe for a propulsion method according to the present invention.

FIG. 2 is a partial cross-sectional view showing a first embodiment of a double steel pipe for a propulsion method according to the present invention constituted by using the steel pipe shown in FIG.

FIG. 3 is a partial sectional view showing a second embodiment of the double steel pipe for a propulsion method according to the present invention.

FIG. 4 is a partial sectional view showing a third embodiment of a double steel pipe for a propulsion method according to the present invention.

FIG. 5 is a partial sectional view showing a fourth embodiment of the double steel pipe for a propulsion method according to the present invention.

FIG. 6 is a partial sectional view showing a fifth embodiment of the double steel pipe for a propulsion method according to the present invention.

FIG. 7 is a partial sectional view showing an example of a conventional double steel pipe for a propulsion method.

[Explanation of symbols]

 Reference Signs List 1 steel pipe (inner pipe) 2 polyethylene layer (or polyurethane layer) 3 polyethylene rope 4 steel pipe (outer pipe) 5 filler (cement mortar layer) 6 polyethylene protective layer (outer layer) 7 shrink tube 8 wire rope 9 asphalt coating layer

Claims (7)

(57) [Claims] 1. A double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is A propulsion method comprising: a layer made of a thermoplastic resin coated on an outer peripheral surface of the layer; and a rope made of a thermoplastic resin wound spirally around the outer peripheral surface of the layer and fixed by heat fusion. For double steel pipe. 2. A double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is formed of the inner pipe. A layer made of a thermoplastic resin coated on the outer peripheral surface of the layer, and a ring-shaped intermittent shrink tube having heat shrinkability wound and fixed on the outer peripheral surface of the layer for a propulsion method. Double steel pipe. 3. A double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is formed of the inner pipe. A layer made of a thermoplastic resin coated on the outer peripheral surface of the layer, a wire rope wound around the outer peripheral surface of the layer, and the layer together with the wire rope wound around the outer peripheral surface of the layer covering the wire rope. A double-walled steel pipe for a propulsion method, comprising: a heat-shrinkable ring-shaped intermittent shrink tube fixed to an outer peripheral surface of the steel pipe. 4. A double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is A layer made of a thermoplastic resin coated on the outer peripheral surface of the layer, an outer layer made of a thermoplastic resin coated on the outer peripheral surface of the layer, and a spirally wound around the outer surface of the outer layer and fixed by heat fusion. A double steel pipe for a propulsion method, comprising a wire rope. 5. A double steel pipe for a propulsion method comprising an inner pipe, an outer pipe, an anticorrosion layer and a filler disposed between the inner pipe and the outer pipe, wherein the anticorrosion layer is formed of the inner pipe. A double-walled steel pipe for a propulsion method, comprising a layer made of a belt-shaped thermoplastic resin wound and covered in a spiral shape so that an end thereof overlaps an outer peripheral surface of the pipe. 6. The double steel pipe for a propulsion method according to claim 2, wherein a thermosetting resin is used in place of the thermoplastic resin. 7. The double steel pipe for a propulsion method according to claim 2, wherein a shrink net having heat shrinkage is used instead of the shrink tube.