JP2001141110A - Small diameter pipe installation method into tunnel having steep curve, and its apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a pipe receiving truck from being derailed from rails and unit pipes forming small diameter pipes from being disconnected from each other even on a steep curve of <=35 m in radius of curvature, and to facilitate the smooth operation. SOLUTION: The pipe receiving base 2 to arrange and support a plurality of small diameter pipes 1 connecting a plurality of unit pipes parallel to each other is provided for each unit pipe of the small diameter pipes 1, the pipe receiving bases 2 connected via bar-like members 6 at a center part, and the connection parts are positioned on the axis of a tunnel, and the leading pipe receiving base 2 is pulled into the tunnel 3 together with a plurality of small diameter pipes 1. A leading truck 10 which constantly travels along the axis of the tunnel 3 is provided and connected to the leading pipe receiving base 2, a wire is stretched between both ends in the horizontal direction of the center part of the leading truck 10 and each pipe receiving base 2, and the difference in internal and external arc lengths of the steep curve is absorbed by the wire to pull the leading truck 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for simultaneously drawing a plurality of small-diameter pipes into a tunnel having a sharp curve such as an upward slope, a downward slope, and a meandering to the left and right.

[0002]

2. Description of the Related Art Conventionally, a plurality of small-diameter pipes are simultaneously drawn into a tunnel buried underground or the like, as disclosed in Japanese Unexamined Patent Publication No.
As shown in Japanese Patent Publication No. 0-068233 and FIG. 13, a plurality of small-diameter pipes 1 in which the other end 1c of another adjacent unit pipe 1a is inserted into the socket portion 1b of the unit pipe 1a via a packing 1d and connected. As shown in FIG. 14, a plurality of these small-diameter pipes 1 are arranged in parallel at intervals and held in parallel with each other. A roller 5 is provided on the base 2 so as to run on a rail 4 provided at the bottom of the tunnel 3, and the respective pipe receiving bases 2 arranged in the longitudinal direction of the small-diameter pipe 1 are connected by upper and lower rod-shaped members 6, and are positioned at the top. The pipe receiving pedestal 2 is pulled into the tunnel 3 from the front by the pulling wire 7. Further, through holes are provided on both horizontal sides of each of the pipe receiving bases, and both ends of the rod-shaped member are allowed to pass through these through holes, and nuts are screwed to ends protruding outside of the through holes, thereby forming a curved portion of the tunnel. When passing through, the rod-shaped member located outside the curved portion expands and shrinks the rod-shaped member located inside, and the other unit pipes 1a in the socket portion 1b of the unit pipe 1a of each of the small-diameter pipes 1 described above. Is moved and passes through the curved part.

[0003]

However, FIG.
As shown in the figure, in the case of a sharply curved portion having a smaller radius of curvature of the curved portion, the pulling wire 7 for pulling the leading tube receiving pedestal 2 moves the leading tube in a direction largely different from the center line of the tunnel 3. Pipe cradle 2 is rail 4 to pull cradle 2
From each other, and the connection between the unit pipes 1a of the small-diameter pipe 1 is also easily disconnected. Such a conventional pull-in method targets a gentle curve having a minimum radius of curvature of 35 m or more in a tunnel, and in a sharp curve portion of 35 m or less,
The position of the pipe cradle will be different, derailing from the rail,
Small diameter pipes may fall off. This kind of tunnel
Normally, the inside diameter is as narrow as about 1 m, so if such an accident occurs especially at a sharp curve, workers cannot easily enter the accident location,
Restoration is time-consuming, which affects the entire construction, such as extending the construction period, and is a major problem.

Accordingly, the present invention has a minimum curvature radius of 35 m.
Even in the following sharp curves, the pipe receiving trolley does not derail from the rail, the unit pipes constituting the small-diameter pipes are not disconnected from each other, and multiple small-diameter pipes that can smoothly work are simultaneously tunneled. An object of the present invention is to solve the above-mentioned problem by providing a method of drawing into a device and an apparatus used for the method.

[0005]

According to the first aspect of the present invention, a plurality of small-diameter pipes in which one end of a small-diameter unit pipe is inserted and connected to the other end of another small-diameter unit pipe are arranged in parallel.
A supporting pipe pedestal is provided for each unit pipe of the small-diameter pipe, and these pipe pedestals are connected to each other with a bar-shaped member above and below the center portion thereof, and each pipe pedestal is positioned at the center line of the tunnel. In the method of pulling the plurality of small-diameter pipes simultaneously into the tunnel by running each pipe cradle on a rail provided at the bottom of the tunnel by pulling the pipe cradle positioned at the head and pulling the pipe cradle at the head, In front of the vehicle, a leading bogie that can always travel along the center line of the tunnel is provided, and this leading bogie and the first pipe cradle are connected by a rod-shaped member, and the central portion of the leading bogie and each pipe cradle in the horizontal direction. Attach wires to both ends, absorb the difference in inner and outer arc length of the sharp curve part with these wires, fix each unit pipe at each pipe cradle,
A method of drawing a small-diameter pipe into a tunnel having a sharply curved portion, which pulls the leading bogie.

In this case, when the leading bogie is provided during the passage of the sharp curve, even if the traction member pulls the leading bogie from a direction different from the direction of the center line of the tunnel, each pipe receiving pedestal is positioned at the center of the tunnel. It runs along a line and can always maintain a posture perpendicular to the center line of the tunnel. At the same time, among the wires located at both ends in the horizontal direction at the center of the leading bogie and each pipe receiving stand, the vehicle travels with the outer arc wire stretched, and at each connection point of the unit pipe of each small diameter pipe, The end of the other unit pipe moves and bends in the socket part, and each pipe cradle always maintains a posture perpendicular to the center line of the tunnel, and the small diameter pipe passes along the tunnel alignment. In addition, since each unit pipe is supported and fixed by the pipe support, each unit pipe of the small-diameter pipe uniformly absorbs the difference between inside and outside corresponding to the curvature in the sharp curve part, The pipe does not come off at the sharp curve.

According to a second aspect of the present invention, in the first aspect of the present invention, the length of the wire between the adjacent pipe receiving pedestals is a length calculated from the radius of curvature of the sharply curved portion. Therefore, in the passage of the sharply curved portion, among the wires located at both ends in the horizontal direction of the center portion of the leading bogie and the respective tube holders, the wires located at the outer arc extend fully and are pulled by the outer wires. Subsequent tube cradle runs, but because the wire length is defined according to the sharp curvature, each tube cradle can run while maintaining its vertical position with respect to the centerline of the tunnel. .

According to a third aspect of the present invention, there is provided an apparatus used in the above method, wherein a plurality of small diameter pipes connected by inserting one end of a small diameter unit pipe into the other end of another small diameter unit pipe are connected. In each unit pipe of the small-diameter pipe, a pipe pedestal is provided and supported, and these pipe pedestals are connected to each other by a rod-shaped member at the center thereof, and each pipe pedestal is positioned at the center line of the tunnel. At the lower end of each of these tube receivers, a roller mounted on a rail provided at the bottom of the tunnel is provided, and a pulling member is provided at the tube receiver positioned at the head. In a device that simultaneously draws in pipes, a leading bogie that can always run along the center line of the tunnel is provided in front of the leading pipe cradle, and this leading bogie is connected to the leading pipe cradle, and the leading bogie is connected to the leading bogie. Provide traction member Wires are attached to both ends of the leading bogie and each horizontal center of the pipe cradle in the horizontal direction, and these wires are used to absorb the difference between the inner and outer arc lengths of the sharply curved portion, and each unit pipe is fixed at each of the above pipe cradle. It is.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the leading bogie is provided with a speed control device such as a brake. Prevents reverse running and escape. According to a fifth aspect of the present invention, in the third or fourth aspect of the invention, the upper and lower ends of each of the pipe receiving pedestals in the horizontal direction are provided with rollers that can contact the inner wall of the tunnel. Thus, it is possible to prevent each pipe receiving base from being lifted.

According to a sixth aspect of the present invention, in any one of the third to fifth aspects of the present invention, among the two pipe pedestals, the pipe pedestal is provided between two adjacent pipe pedestals. The tube cradle overturn prevention means, which has a configuration in which a bar-shaped member is arranged in a crossing manner at the center of the cradle, is disposed at an appropriate interval. This prevents each pipe cradle from inclining and falling down due to the weight of the small-diameter pipe or pipe cradle, even when the small-diameter pipe to be transferred is long on the ascending slope or the descending slope. Can be maintained in a position perpendicular to the center line of the camera. According to a seventh aspect of the present invention, in any one of the third to sixth aspects of the present invention, the small-diameter pipe is provided with a bellows pipe or a flexible pipe at a butt end of a straight tubular adjacent small-diameter unit pipe. It is constructed by connecting over a flexible tube. Accordingly, even at a portion having a curved portion having a smaller radius of curvature, it is possible to smoothly bend at a connecting portion of each unit pipe corresponding to the curve of the curved portion.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of the present invention, in which one small end of a unit pipe is inserted into the other end of another unit pipe and connected to each other.
The small-diameter pipes 1 are arranged in parallel at a distance from each other, and at the lower end of each of the pipe receiving bases 2, casters 5 ′ that can freely move in the running direction are provided. ′ Is placed on the rails 4 of the tunnel 3, and each of these pipe receiving pedestals 2 is a bar-shaped member 6 above and below the center of each pipe receiving pedestal 2.
Are connected by The unit pipe 1a accommodates a power cable and has an outer diameter of about 150 mm and a length of about 2 m.

In addition, a leading carriage 10 having a fixed length is provided in front of the tube receiving stand 2 located at the head of the tube receiving stand 2, and the leading carriage 10 is provided at the lower end of the front and rear portions thereof and can freely move in the running direction. A simple caster 11 is mounted on the rail 4, and the leading truck 10 and the front pipe receiving stand 2 are connected by bar-shaped members 12 above and below a central portion thereof, and a pulling wire 13 is provided at a front end of the leading truck 10. The pulling wire 13 is pulled from the front of the tunnel 3, and the leading bogie 10 and each pipe cradle 2 run along the rail 4, and a large number of small-diameter pipes 1 supported by these pipe cradles 2 are put into the tunnel 3. Pull in. Rollers 14 are provided on the front and rear portions of the leading bogie 10 and on the right and left sides thereof in proximity to the inner wall of the tunnel 3. Accordingly, the leading bogie 10 can always travel along the center line of the tunnel 3 in a state of being fitted into the tunnel 3 so to speak. Each caster 11 of the leading bogie 10 has a brake so that the traveling speed can be controlled.

As shown in FIG. 2, the center of the tube cradle 2 in the horizontal direction and the leading tube cradle 2 and the leading bogie 10 are connected so as to connect the mutually adjacent tube cradle 2.
A wire 8 is stretched between both ends in the horizontal direction at the center. The length of each wire 8 between these adjacent pipe cradles 2 or between the leading bogie 10 and the leading pipe cradle 2 is calculated from the radius of curvature of the sharp curve of the tunnel 3. The length of the outer arc of.

As a result, as shown in FIG. 2, even when the pulling wire 13 is pulled from a direction different from the center line direction of the tunnel 3 in a sharply curved portion curved in the horizontal direction, the leading bogie 10 receives the pulling wire 13 Since the respective tube receiving stands 2 behind the carriage 10 are connected by bar-shaped members 6 and 12 (described in FIG. 1) above and below the central portion thereof, they always travel along the center line of the tunnel 3. . As shown in FIG. 3, the wire 8 stretched between both ends of the center of each pipe holder 2 in the horizontal direction extends fully on the outer side of the arc, loosens on the inner side, and loosens on the outer side. 8, the pipe cradle 2 travels. However, as described above, since the length of the wire 8 is defined in accordance with the curvature of the sharp curve, each pipe cradle 2 is located at the center line of the tunnel 3. On the other hand, the vehicle runs while maintaining the vertical position. As the wire 8, a commercially available wire having an outer diameter of 6 to 12 mm is used.

When the tunnel 3 has an uphill slope and there is no conventional leading bogie but passes only by the pipe cradle, FIG.
As shown in the figure, since the pipe cradle 2 cannot maintain a posture perpendicular to the center line of the tunnel 3, the connection of the unit pipe of the small-diameter pipe 1 may drop off.
5, the leading bogie 10 travels along the center line of the tunnel 3 and each of the subsequent pipe cradles can maintain a posture perpendicular to the center line of the tunnel 3 as shown in FIG. Can be pulled in. The same effect as described above can be obtained in the case of a down slope.

As shown in FIG. 6, when the small-diameter pipe 1 to be transported becomes longer on an ascending slope or a descending slope, each of the pipe receiving pedestals 2 causes the small-diameter pipe 1 and Due to the own weight of the pipe cradle 2, the pipe is tilted downward and falls down, and the pipe cradle 2 cannot maintain the perpendicularity to the center line of the tunnel, so that the small-diameter pipe 1 may fall off from the pipe cradle 2. Therefore, as shown in FIG. 7, as a member for reinforcing the rod-shaped member 6, the rod-shaped member is cross-shaped at the center of the tube holder 2 and between two adjacent tube receivers 2. The tube cradle overturn prevention means 6 ′ having the arranged configuration is appropriately and preferably disposed about every fourth tube cradle 2.

FIG. 8 shows the details. By providing the fall prevention means 6 ′ at the center of the pipe cradle 2, each pipe cradle 2 is always positioned at the center line of the tunnel in order to prevent the pipe cradle 2 from inclining in the downward direction. A vertical posture can be maintained. This fall prevention means 6 '
Is arranged not only at the rear of the tube receiver 2 but also preferably, preferably, at about every four tube receivers 2. When the length of the connected small-diameter pipe 1 increases, the front tube receiver 2 This is to prevent a force that inclines in the downward direction of the gradient from being easily applied to the pipe receiving base 2 and the intermediate pipe receiving stand 2.

FIG. 9 shows a detailed view of the pipe pedestal 2. The pipe pedestal 2 is composed of a lattice-like frame body, a small-diameter pipe 1 is passed through each frame, and lower ends of legs 2a projecting downward. Is provided with casters 5 'which can run on rails 4 provided at the bottom of the tunnel 3, and the inner wall surface of the tunnel 3 is provided at the top and at the tips of the protruding arms 2b, 2c, 2d projecting left and right, respectively. Is provided with a roller 15 which can be freely contacted. One end of a rod-shaped member 6 is connected to the upper and lower portions of the center of the tube holder 2, and one end of a wire 8 is fixed to both ends in the horizontal direction of the center. Are locked by a jig capable of adjusting the length of the wire 8 between the adjacent pipe receiving stands 2. Further, the rod-shaped member 6 and the leading bogie 10 for connecting the respective pipe receiving bases 2 to each other and the leading pipe receiving base 2
Both ends of the rod-shaped member 12 connecting the two members are fixed so as to be angularly displaceable.

In each of the pipe receiving stands 2, each supported small-diameter pipe 1 is fixed. As shown in FIGS. 10 and 11, horizontal fixing pieces 16, 16 are provided on one side of a pipe receiving stand 2 located above and below each small-diameter pipe 1, and the upper horizontal projecting piece 16 is penetrated. A movable holding piece 18 having a concave lower surface is provided at the lower end of the rod 17, and two nuts 19, 1, 1 are provided on the upper and lower portions of the rod 17 sandwiching the horizontal projecting piece 16.
9 is screwed on, and these nuts 19, 19 are moved so that the length of the rod 17 can be adjusted. A holding piece 2 having a concave upper surface is provided on a horizontal projecting piece 16 located below.
0 is provided, and the small-diameter pipe 1 is held between the movable holding piece 18 and the holding piece 20. In addition, since each unit pipe 1a is supported and fixed by the pipe holder 2, even when passing through the above-mentioned sharply curved portion, each unit pipe 1a of the small-diameter pipe 1 uniformly absorbs a curve by an equal amount and a small amount. However, the connection between the unit pipes 1a is not disconnected at the sharply curved portion.

In the above embodiment, the other end of the adjacent unit pipe 1a is inserted and connected to the socket provided at one end of the unit pipe 1a of the small-diameter pipe 1 via packing. 12 (a) and (b), at a portion having a curved portion having a smaller radius of curvature, at the abutting end of an adjacent straight unit pipe 1a ', as shown in FIGS. Can also be connected.
In addition, the leading bogie 10 according to the present invention is not limited to the configuration of the above-described embodiment, as long as it can travel along the center line of the tunnel 3. Furthermore, the fixing structure of the pipe receiving stand 2 and the small-diameter pipe 1 is not limited to the configuration of the above embodiment.

[0021]

According to the first, second, and third aspects of the present invention, when the leading bogie is provided when passing through a sharp curve portion, the traction member moves the leading bogie from a direction different from the direction of the center line of the tunnel. Even when the vehicle is towed, the trailing bogie travels along the center line of the tunnel, so that each of the subsequent pipe supports connected to the bogie can always maintain a posture perpendicular to the center line of the tunnel. At the same time, of the wires located at both ends of the central part of each pipe holder, the wire runs outside the track and is stretched, and at each connection point of the unit pipe of each small-diameter pipe, another unit in the socket part The movement of the other end of the pipe is reduced, so that each pipe cradle always keeps its attitude perpendicular to the centerline of the tunnel and passes through the small diameter pipe along the tunnel alignment. In addition, since each unit pipe is supported and fixed by the pipe support, the unit pipe of the small-diameter pipe uniformly and uniformly absorbs the difference between the inside and outside corresponding to the curvature in the sharp curve portion, and Is designed so that it does not come off at the sharp curve. Therefore, according to the present invention, even in a tunnel having a sharply curved portion having a radius of curvature of 35 m or less, the pipe cradle supporting and supporting each small-diameter pipe does not come off from the rail in the tunnel, and the small-diameter pipe can be used. Therefore, the unit pipes can be smoothly drawn in without disconnecting.

Further, the invention of claim 4 is the same as the above-mentioned claim 3.
In addition to the effects of the invention described in the above item, it is possible to prevent reverse running and run-off even on a rising slope or a falling slope of the tunnel. According to the invention of claim 5, in addition to the effects of the invention of claim 1, the leading truck and each pipe receiving stand can be prevented from floating.
Smooth running is possible even when passing through the sharply curved sections at the top, bottom, left and right of the tunnel. Further, in addition to the effects of the third to fifth aspects of the present invention, the invention according to claim 6 provides a fall prevention means at the center of the pipe support so that the pipe support can be inclined even in an upward slope. Can be prevented from falling down. Therefore, since the pipe cradle can always maintain the posture perpendicular to the center line of the tunnel, smooth retraction is possible. In addition, in addition to the effects of the inventions of claims 3 to 6, in addition to the effects of the inventions of claims 3 to 6, even in a portion having a curved portion having a smaller radius of curvature, each unit pipe corresponds to the curve of the curved portion. Since the bellows pipe and the flexible pipe at the connecting point of (1) are bent, a small diameter pipe can be smoothly pulled in.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration inside a tunnel according to an embodiment of the present invention.

FIG. 2 is a schematic plan view showing a leading bogie and a pipe cradle passing through a sharply curved portion of a tunnel according to the embodiment of the present invention.

FIG. 3 is a schematic plan view showing the condition of each pipe pedestal and wires on both sides passing through a sharply curved portion of the tunnel according to the embodiment of the present invention.

FIG. 4 is a schematic side view showing a posture state of each pipe receiving pedestal on an upward slope of a tunnel when there is no leading bogie.

FIG. 5 is a schematic side view showing an attitude state of each pipe cradle on the uphill of the tunnel according to the embodiment of the present invention.

FIG. 6 is a schematic side view showing a posture state of each pipe cradle on an upward slope of a tunnel when there is no overturn prevention means in the embodiment of the present invention.

FIG. 7 is a schematic side view showing a posture state of each pipe cradle on a rising slope of a tunnel in a case where there is a fall prevention means in the embodiment of the present invention.

FIG. 8 is a detailed view showing a configuration of a fall prevention means of the tube holder shown in FIG. 7 in the embodiment of the present invention.

FIG. 9 is a front view of a tube support supporting a plurality of small-diameter unit pipes in the tunnel according to the embodiment of the present invention.

FIG. 10 is a front elevational view showing a structure for fixing a small-diameter pipe to a pipe holder according to an embodiment of the present invention.

FIG. 11 is a side elevational view showing a structure for fixing a small-diameter pipe to a pipe holder according to an embodiment of the present invention.

FIG. 12 is a cross-sectional side view showing a connection configuration of unit pipes forming a small-diameter pipe in another embodiment of the present invention.

FIG. 13 is a cross-sectional side view showing a connection structure between unit pipes constituting a small-diameter pipe according to the present invention and a conventional small-diameter pipe.

FIG. 14 is a schematic side view showing a conventional method of drawing a small-diameter pipe into a tunnel.

FIG. 15 is a schematic plan view showing a situation in which a small-diameter pipe is drawn into a tunnel according to a conventional method of passing a sharply curved portion.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Small diameter pipe 1a Unit pipe 2 Pipe cradle 3 Tunnel 4 Rail 5 Roller 5 'Caster 6 Bar-shaped member 6' Pipe cradle overturn prevention means 7 Traction member 8 Wire 10 Leading trolley 11 Caster 12 Rod-shaped member 13 Traction wire 14 Leading trolley Roller 15 Roller of tube holder 21 Bellows tube 22 Flexible tube

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaru Tanaka 1-3-1 Uchisaiwai-cho, Chiyoda-ku, Tokyo Inside Tokyo Electric Power Company (72) Inventor Takashi Oba 4-83-3, Shibaura, Minato-ku, Tokyo Shares Company Kandenko

Claims (7)

[Claims] 1. A small-diameter unit pipe is provided with a plurality of small-diameter pipes connected in parallel by inserting one end of the small-diameter unit pipe into the other end of another small-diameter unit pipe. Each of these tube receivers is connected to each other by bar-shaped members at the top and bottom of the center of each other to position each tube receiver at the center line of the tunnel, and to pull the tube receiver positioned at the head. In a method in which multiple small diameter pipes are simultaneously drawn into the tunnel by running each pipe cradle on the rail provided at the bottom of the tunnel, it is always possible to run along the center line of the tunnel in front of the first pipe cradle A leading truck and connect this leading truck to the top pipe cradle,
Wires are attached to both ends in the horizontal direction at the center of each of the pipe carriers after the leading bogie and the leading bogie, and these wires are used to absorb the difference between the inner and outer arc lengths of the sharply curved portion. A method of drawing a small-diameter pipe into a tunnel having a sharply curved part, wherein the pipe is fixed and the leading bogie is towed. 2. The steep curved part according to claim 1, wherein the length of the wire between the adjacent pipe receiving pedestals is a length calculated from the radius of curvature of the steep curved part. How to pull a small diameter pipe into a tunnel. 3. A small-diameter unit pipe having one end of one small-diameter unit pipe inserted into the other end of another small-diameter unit pipe and arranged in parallel to support a plurality of small-diameter pipes. Each of these pipe pedestals is connected to each other by bar-shaped members at the top and bottom of the center thereof to position each of the pipe pedestals at the center line of the tunnel, and at the lower end of each of these pipe pedestals, A caster mounted on a rail provided at the bottom of the tunnel is provided, and a traction member is provided at the top of the pipe cradle, and a device for simultaneously drawing a plurality of small-diameter pipes into the tunnel is provided in front of the first pipe cradle. ,
A leading bogie that can always travel along the center line of the tunnel is provided, this leading bogie is connected to the leading pipe cradle, a traction member is provided on the leading bogie, and the central part of the leading bogie and each pipe cradle are horizontal. A tunnel having a sharply curved portion characterized by attaching wires to both ends in the direction, absorbing the difference in the inner and outer arc lengths of the sharply curved portion with these wires, and fixing each unit pipe at each of the pipe cradles. Small-diameter pipe drawing device. 4. The apparatus according to claim 3, wherein a speed control device is provided on the leading bogie. 5. The sharply curved portion according to claim 3, wherein rollers are provided at the upper portion and at both ends of the central portion of each of the tube receiving stands, respectively, so as to be able to abut against the inner wall of the tunnel. A small-diameter pipe pull-in device into a tunnel. 6. A tube pedestal having a configuration in which a bar-shaped member is arranged in a cross-like manner between two adjacent tube pedestals and at the center of the tube pedestal. Characterized in that the fall prevention means are arranged at appropriate intervals.
An apparatus for drawing a small-diameter pipe into a tunnel having a sharply curved portion according to any one of claims 3 to 5. 7. The small-diameter pipe is formed by connecting a bellows pipe or a flexible pipe to a butt end of an adjacent small-diameter unit pipe having a straight tubular shape.
Item 7. A device for drawing a small-diameter pipe into a tunnel having a sharply curved portion according to any one of Items 6 to 6.