JP3633725B2 - Pipe retractor - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a pipe retractor for laying underground pipes for gas, water, communication, etc. in the ground by non-open cutting.
[0002]
[Prior art]
As an underground laying method for piping by non-open cutting, a road-mounted propulsion device is installed on the ground, and in the first step, a borehole is drilled in the ground, and in the second step, the target pipe is drawn into the drilled borehole A construction method has been proposed.
[0003]
6 (A) and 6 (B) show the above-described drawing method, (A) is the first step (boring hole drilling step) of the method, and (B) is the second step (pipe pulling) of the method. Process). The pipe laying path is provided with a start shaft a on one side and a reaching shaft b on the other side, and a road-mounted propulsion device c is installed on the ground on the start shaft a side. The propulsion unit c includes a guide drill unit that performs an action of feeding a rotating rod with a required propulsive force or pulling it back with a required pulling force.
[0004]
In the first step shown in FIG. 6 (A), the drill head f is attached to the tip of the rod e fed out from the propulsion device c, and the drill head f enters the ground while rotating and arrives from the start shaft a. The drill head f is advanced along the path to the shaft b. At this time, bentonite muddy water is jetted from the tip of the drill head f, and the water flow advances while cutting the soil, and rods e are sequentially added so that a borehole is dug into the ground of the route to the reaching shaft b. ing.
[0005]
Next, in the second step shown in FIG. 6 (B), the drill head f is removed on the side of the reaching shaft b, and instead of this, an expanded reamer n adapted to the diameter of the buried pipe and an object to be pulled in at the end of the rod e. Tube m (polyethylene pipe, hereinafter referred to as PE pipe) is connected in series, and the rod e is pulled back by the pulling force of the propulsion unit c. In this process, the drawing target pipe m is drawn into the boring hole.
[0006]
[Problems to be solved by the invention]
By the way, when constructing the pipe retraction method described above, even if the formed boring hole is expanded with an expansion reamer, there is considerable frictional resistance between the surface of the retraction pipe and the periphery of the boring hole, and sand that is particularly easy to collapse In the case of terrestrial geology, the frictional resistance is further increased.
Moreover, as a means for solving the above-mentioned problems, it is conceivable to reduce the frictional resistance by covering the drawing tube with a coating material or the like, but the problem of the storage location of the coating material for covering the entire length of the drawing tube over a long distance Or the problem of the means for covering the accommodated film material in a drawing tube appropriately derives.
[0007]
The present invention has been made in response to the above problems, and an object of the present invention is to provide a pipe retracting apparatus that can smoothly lay a pipe to be retracted over a long distance using an existing retracting apparatus. Is.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention forms a starting shaft on one side of the laying path and a reaching shaft on the other side, and makes a rotating rod enter the ground to drill into the ground from the starting shaft to the reaching shaft. A pipe drawing device for drilling a hole and being connected to the boring hole in series with the previous stage of the drawing pipe,
The pipe retracting device includes a cylindrical body portion having an outer diameter substantially the same as the retracting pipe,
A connecting rod extending in the axial direction at the approximate center of the body portion;
A coating material housed in a bellows shape in front of the body part;
A plurality of disc-shaped spacers disposed behind the coating material and fixed to the connecting rod;
The coating material is configured so that the terminal portion of the coating material is fixed in a state of being folded back in the vicinity of the borehole opening portion on the reaching shaft side, and the coating material is covered around the drawing pipe by being drawn into the soil together with the drawing pipe. It is characterized by that.
[0009]
Further, the disc-shaped spacer is provided with protruding pieces protruding outward at a plurality of locations on the circumference, and the protruding pieces are arranged alternately in adjacent spacers. To do.
[0010]
In the pipe retractor according to the present invention, two spacers having elasticity having an outer diameter substantially equal to the inner diameter of the body portion are provided behind the disk-shaped spacer with a required gap, and the gap It is characterized by being filled with a lubricant.
[0011]
The tube drawing apparatus according to the present invention is characterized in that a diameter-enlarged portion is provided at the rear portion of the body portion and a sealing material is provided on the inner wall surface of the diameter-enlarged portion.
[0012]
[Action]
According to the pipe drawing device according to the present invention, since the drawing device is connected to the front stage of the drawing tube, the drawing device is drawn into the borehole prior to the drawing tube. Therefore, the borehole can be leveled to some extent, and the meandering in the hole can be corrected.
Furthermore, since the coating material is housed in a bellows shape in the apparatus, the terminal portion of the coating material is fixed in a state where it is folded back near the borehole opening on the reaching shaft side, so that in the retraction process sequentially The coating material can be discharged to the rear of the apparatus, and the coating material can be covered with the subsequent drawing tube, and the frictional resistance due to the drawing can be reduced. At that time, since the coating material is housed in a bellows-like shape inside the retracting device, it can be accommodated in a relatively large amount, can accommodate a retractable pipe over a long distance, and further, the latter stage of the coating material. Since a plurality of disc-shaped spacers are disposed in the inner wall, the bellows-shaped one can be stretched by allowing the coating material to pass between the spacer and the inner wall surface of the apparatus.
[0013]
According to the second aspect of the present invention, the disc-shaped spacer includes protrusions protruding outward at a plurality of locations on the circumference, and the protrusions are alternately arranged at adjacent spacers. Since they are arranged, when the coating material is discharged rearward, the projecting pieces abut on the inner peripheral surface of the coating material evenly, and the coating material is properly stretched without being bent.
[0014]
According to the third aspect of the present invention, the coating material stretched by the disk-shaped spacer passes between the two spacers having elasticity and the inner wall surface of the apparatus. During this passage, the lubricant passes through the lubricant filling gap provided between the two spacers, so that the lubricant is applied to the inner peripheral surface of the coating material. Therefore, the sliding movement of the drawing tube is promoted, and the frictional resistance can be further reduced.
[0015]
According to the fourth aspect of the present invention, since the enlarged portion is provided in the body portion of the pipe retractor and the sealing material is provided on the inner wall surface of the enlarged portion, the earth and sand flows into the device when the boring hole is inserted. Can be prevented.
[0016]
According to the invention described in claim 5, since the polytube is used as the coating material, it can be accommodated in a large amount in the apparatus, and the construction cost can be reduced because the cost is low. it can.
[0017]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a cross-sectional view of a pipe retractor according to the present invention.
The tube retracting device 1 includes a body portion 11 formed in a substantially cylindrical shape having the same material and the same outer diameter as the tube 7 to be retracted, a connecting rod 12 extending in the axial direction substantially at the center of the body portion 11, A polytube 13 that is folded and accommodated in a bellows shape in front of the body portion 11, a disk spacer 14 that is disposed behind the polytube 13 and fixed to the connecting rod 12, and is disposed behind the disk spacer 14. It is constituted by urethane spacers 15 and 16 provided.
[0018]
The body portion 11 has a front portion formed in a tapered shape, and a rear portion is provided with an enlarged diameter portion 11a. A rubber tube 17 as shown in FIG. 2A is disposed on the inner wall surface of the enlarged diameter portion 11a as a sealing material, and the overall length of the rubber tube 17 is longer than the entire length of the enlarged diameter portion 11a. Has been. The rubber tube 17 is pressed against the inner wall surface of the enlarged diameter portion 11a by a sealing material 18 as shown in FIG. The sealing material 18 is made of a material having elasticity such as plastic, and is inserted inside the rubber tube 17 to press the rubber tube 17 against the inner wall surface of the enlarged diameter portion 11a.
[0019]
The connecting rod 12 is made of a metal such as iron, and an eye ring 12a for connecting a rotating rod that pulls the tube retracting device 1 is provided at the front end portion, and at the rear end portion. A shackle 12b is provided.
As shown in FIG. 3A, the disk spacer 14 includes projecting pieces 14a projecting outward at four locations on the circumference. A plurality of spacers 14 are fixed to the connecting rod 12, and as shown in FIG. 3 (b), the protrusions 14a are alternated between adjacent spacers.
[0020]
The outer diameters of the urethane spacers 15 and 16 are substantially the same as the inner diameter of the body portion 11, and are fixed to the connecting rod 12 behind the disk spacer 14. The urethane spacers 15 and 16 are disposed with a required gap S, and the gap S is filled with a lubricant. Therefore, the lubricating material impregnates the urethane spacers 15 and 16 and does not flow out of the gap S.
[0021]
In the pipe retractor 1 configured as described above, the polytube 13 accommodated in a bellows shape at the tip portion passes between the protruding piece 14a of the disk spacer 14 and the inner wall surface of the body portion 11. At this time, since the projecting pieces 14a are alternately arranged, the projecting pieces 14a are in uniform contact with the inner peripheral surface of the polytube 13, and the polytube 13 is properly stretched without being bent.
The stretched polytube 13 passes between the urethane spacers 15 and 16 and the inner wall surface of the body portion 11. At this time, since the urethane spacers 15 and 16 have elasticity, the polytube 13 can pass even if the outer diameters of the urethane spacers 15 and 16 are substantially the same as the inner diameter of the body portion 11. . Further, when passing, the polytube 13 contacts the urethane spacers 15 and 16 and passes through the gap S filled with the lubricant, so that the lubricant is applied to the inside of the polytube 13. Is done.
[0022]
Next, the usage form of the pipe drawing-in apparatus of this invention is demonstrated.
In FIG. 4, the code | symbol 2 shows the start shaft, and the code | symbol 3 shows an arrival shaft. On the start shaft 2 side, a road-mounted propulsion device 4 is installed.
The propulsion unit 4 is equipped with a guide drill unit 41 that feeds the rotating rod 5 for underground excavation with a required propulsive force and pulls it with a required retracting force, as in the prior art. The rod 5 has a length corresponding to the entire length of the pipe laying path by sequentially adding rods having a required length. A power unit track (not shown) serving as a power source is disposed on the propulsion device 4 side.
[0023]
The construction mode in the first step is the same as the conventional example described in FIG. That is, the drill head f is attached to the tip of the rod 5 fed out from the propulsion device 4. When propelling the drill head f into the ground while rotating, drilling bentonite muddy water from the tip of the drill head and cutting the soil with the water flow, a borehole is formed in the ground to the reach shaft 3 I try to dig.
[0024]
At the time of this excavation, the signal g from a transmitter (not shown) incorporated in the drill head f is detected by the ground detector h, as in the conventional example described in FIG. The tip position of the boring is confirmed, and the excavation direction of the drill head f being excavated is corrected by remote control from the ground.
[0025]
In the second step shown in FIG. 4, the drill head f is removed from the tip of the rotating rod 5 that has reached the reaching shaft 3, and instead of this, the hole expanding reamer 6 and the The pipe drawing device 1 and the pipe (steel pipe) 7 to be laid are connected in series.
[0026]
Then, as a method of drawing the pipe 7 into the borehole, as shown in FIG. 5, the terminal end of the polytube 13 is fixed with the anchor bolt 13 a in the state where the end portion of the polytube 13 is folded back in the vicinity of the opening of the borehole. Then, together with pulling the rotating rod 5 on the start shaft 2 side, a conventionally known main pushing device 8 may be installed inside the reach shaft 3. The main pushing device 8 includes a jack unit 81 and a press-fit portion 82 that horizontally moves back and forth along the guide rail 83 by the extension / retraction operation of the jack. The jack unit 81 is installed so as to receive a reaction force of the pressing force by the bearing wall 21 provided in the shaft.
[0027]
According to the above-described equipment configuration, the pipe retracting device 1 is connected to the front stage of the retracting pipe 7, so that it is retracted into the borehole prior to the retracting pipe 7. Therefore, the borehole can be leveled to some extent, and the meandering in the hole can be corrected. Moreover, the pipe | tube 7 is covered with the polytube 13 discharged | emitted from the pipe drawing apparatus 1, being drawn in in a boring hole. Therefore, since the surface of the pipe 7 is in contact with only the polytube 13 and is not in direct contact with the soil, the frictional resistance is reduced.
Further, since the polytube 13 is coated with a lubricant, the sliding movement of the tube 7 becomes smooth, and the frictional resistance can be further reduced.
[0028]
【The invention's effect】
As described above, according to the pipe retractor according to the present invention, since the retractor is connected to the front stage of the retractable pipe, it is retracted into the borehole prior to the retractable pipe. Therefore, the borehole can be leveled to some extent, and the meandering in the hole can be corrected.
Furthermore, since the coating material is housed in a bellows shape in the apparatus, the terminal portion of the coating material is fixed in a state where it is folded back near the borehole opening on the reaching shaft side, so that in the retraction process sequentially The coating material can be discharged to the rear of the apparatus, and the coating material can be covered with the subsequent drawing tube, and the frictional resistance due to the drawing can be reduced. At that time, since the coating material is housed in a bellows-like shape inside the retracting device, it can be accommodated in a relatively large amount, can accommodate a retractable pipe over a long distance, and further, the latter stage of the coating material Since a plurality of disc-shaped spacers are disposed in the inner wall, the bellows-shaped one can be stretched by allowing the coating material to pass between the spacer and the inner wall surface of the apparatus.
[0029]
According to the second aspect of the present invention, the disc-shaped spacer includes protrusions protruding outward at a plurality of locations on the circumference, and the protrusions are alternately arranged at adjacent spacers. Since they are arranged, when the coating material is discharged rearward, the projecting pieces abut on the inner peripheral surface of the coating material evenly, and the coating material is properly stretched without being bent.
[0030]
According to the third aspect of the present invention, the coating material stretched by the disk-shaped spacer passes between the two spacers having elasticity and the inner wall surface of the apparatus. During this passage, the lubricant passes through the lubricant filling gap provided between the two spacers, so that the lubricant is applied to the inner peripheral surface of the coating material. Therefore, the sliding movement of the drawing tube is promoted, and the frictional resistance can be further reduced.
[0031]
According to the invention described in claim 4, since the enlarged diameter portion is provided in the body portion of the pipe retracting device and the sealing material is provided on the inner wall surface of the enlarged diameter portion, the earth and sand flows into the device when the bored hole is inserted. Can be prevented.
[0032]
According to the invention described in claim 5, since the polytube is used as the coating material, it can be accommodated in a large amount in the apparatus, and the construction cost can be reduced because the cost is low. it can.
[Brief description of the drawings]
FIG. 1 is an explanatory view of a pipe retracting apparatus of the present invention. FIG. 2 is an explanatory view of parts of the pipe retracting apparatus. FIG. 3 is an explanatory view of a disk spacer. Explanatory drawing of retractor use form [Fig. 6] Explanatory drawing of conventional flow molding method using road-mounted propulsion machine [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipe drawing-in apparatus 11 Body part 12 Connecting shaft 13 Poly tube 13a Anchor bolt 14 Disc spacer 15 Urethane spacer 16 Urethane spacer 17 Rubber pipe 18 Sealing material 2 Starting shaft 3 Reaching shaft 31 Bearing wall 4 Road-mounted propulsion device 41 Guide Drill unit 5 Rotating rod 6 Expanded reamer 7 Pipe 8 Main pushing device 81 Jack unit 82 Press-fit part 83 Guide rail S Gap

Claims (5)

A starting shaft is formed on one side of the laying path, and a reaching shaft is formed on the other side. A rotating rod is inserted into the ground to drill a borehole into the ground from the starting shaft to the reaching shaft. A pipe retractor connected in series to the previous stage and pulled in,
The pipe retracting device includes a cylindrical body portion having an outer diameter substantially the same as the retracting pipe,
A connecting rod extending in the axial direction at the approximate center of the body portion;
A coating material housed in a bellows shape in front of the body part;
A plurality of disc-shaped spacers disposed behind the coating material and fixed to the connecting rod;
The coating material is configured so that the terminal portion of the coating material is fixed in a state of being folded back in the vicinity of the borehole opening portion on the reaching shaft side, and the coating material is covered around the drawing pipe by being drawn into the soil together with the drawing pipe. A pipe retractor characterized by that. The disk-shaped spacer includes protrusions protruding outward at a plurality of locations on the circumference, and the protrusions are arranged alternately in adjacent spacers. Item 1. A pipe retractor according to Item 1. The pipe retractor according to claim 1, wherein
Two spacers having elasticity with an outer diameter substantially the same as the inner diameter of the body portion are provided behind the disk-shaped spacer with a required gap, and the gap is filled with a lubricant. A pipe retractor characterized by that. The pipe retractor according to claim 1, wherein
A pipe retractor comprising: a diameter-enlarged portion provided at a rear portion of the body portion; and a sealing material provided on an inner wall surface of the diameter-enlarged portion. 5. The pipe drawing device according to claim 1, wherein the coating material is a polytube.

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