Pipe roof pipe feeding method for portal arch

Abstract

This invention discloses a pipe delivery method for a pipe arch system at an opening, comprising the following steps: S1, erecting an arch at a pre-set opening, the arch having several pipe holes along its curvature; S2, installing a pipe delivery device on the arch, the device including an arc-shaped track and a delivery structure, the arc-shaped track being positioned along the arch's curvature, and the delivery structure being slidably positioned on the arc-shaped track; S3, inserting the first end of the pipe to be pushed into the corresponding pipe hole on the arch, and connecting the delivery structure to the pipe; applying force to the pipe through the delivery structure, driving the pipe to be gradually pushed into the arch along the direction of the pipe hole; S4, after pushing one pipe, moving the delivery structure along the arc-shaped track to the corresponding position of the next pipe hole, repeating S3 until all pipe holes are delivered. This method ensures that the pipe is aligned and pushed at a consistent angle at each hole, the pushing direction is limited by the pipe hole, avoiding pipe bending and deformation, and all pipe holes can be delivered in a single setup, resulting in high construction efficiency.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction technology, and specifically to a pipe roof delivery method for tunnel arch arching. Background Technology

[0002] Pipe roof construction is commonly used in tunnel engineering, especially at the tunnel entrance, where the surrounding rock is often weathered and broken, and the rock quality is poor. To ensure the safety of entering the tunnel, pipe roofs are often used as advanced support. Traditional pipe roof construction requires the construction of a drilling platform, resulting in poor drilling quality. The pipe roof and drill rod need to be manually replaced. The pipe roof pushing process is separated from the drilling process. First, holes are drilled in batches, and then the pipe roofs are manually inserted, which is inefficient and slow.

[0003] There are two common methods for pipe delivery in pipe roof pushing. The first method is to use an excavator bucket to push the pipes. However, because it is difficult to control the pushing process, any deviation in the pushing angle will cause the pipe roof steel pipes to bend or deform, affecting the subsequent grouting effect and construction quality. The second method is to use a pipe jacking machine or drilling machine to push the pipes. However, since there are usually many pipe roofs at the tunnel entrance, when using a pipe jacking machine or drilling machine to push the pipes, it is necessary to set up a working platform according to the location of each hole, and adjust the position, angle and height of the pushing machine, which is slow and seriously affects the construction progress.

[0004] Therefore, to solve the above problems, a pipe roof delivery method for arch arches at tunnel entrances is needed, which can continuously push the pipe roof and improve the efficiency and quality of pipe delivery construction. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to overcome the defects in the prior art and provide a pipe roof delivery method for arch arches at tunnel entrances, which can continuously push the pipe roof and improve the efficiency and quality of pipe delivery construction.

[0006] The present invention provides a pipe-feeding method for a pipe roof for use in arched openings, comprising the following steps:

[0007] S1. An arch is erected at the pre-set opening, and the arch is provided with several pipe holes along its curvature;

[0008] S2. A pipe-feeding device is installed on the arch, the pipe-feeding device including an arc track and a pipe-feeding structure, the arc track is installed on the arch along the curvature of the arch, and the pipe-feeding structure is slidably installed on the arc track.

[0009] S3. Insert the first end of the pipe to be pushed into the corresponding pipe hole on the arch and connect the pipe feeding structure to the pipe; apply force to the pipe through the pipe feeding structure to drive the pipe to be gradually pushed into the arch along the direction of the pipe hole.

[0010] S4. After completing the pushing of one pipe, move the pipe feeding structure along the arc track to the corresponding position of the next pipe hole, and repeat S3 until the pipe feeding operation of all pipe holes is completed.

[0011] Furthermore, the pipe feeding structure includes a base, a power source, and a limiting member. The power source is disposed on the base, and the base is slidably disposed on the arc-shaped track. In step S3, the limiting member is sleeved on the outer end of the pipe. The power source is connected to the limiting member through a connecting cable. The power source drives the connecting cable to rewind, so as to apply force to the limiting member and push the pipe into the arch.

[0012] Furthermore, the arc-shaped track includes two parallel and spaced-apart first arc-shaped tracks and a second arc-shaped track, both of which are in the same plane.

[0013] Furthermore, the pipe feeding structure also includes guide seats, which are in two sets and slide in cooperation with the first arc-shaped rail and the second arc-shaped rail respectively. The base is located between the two sets of guide seats. In step S4, when the pipe feeding structure moves along the arc-shaped rail, the two sets of guide seats slide synchronously along the first arc-shaped rail and the second arc-shaped rail respectively, forming a limiting constraint on the base from both sides.

[0014] Furthermore, the pipe feeding structure also includes a rotating connector, which is located between the base and the guide seat, and its rotation axis is set in the vertical direction. In step S4, when the pipe feeding structure is moved along the arc track, the base rotates relative to the guide seat around the vertical axis through the rotating connector to adapt to the curvature change of the arc track and avoid the base from getting stuck when moving on the arc.

[0015] Furthermore, the guide seat is provided with a locking element; in step S3, before the end of the pipe is inserted into the pipe hole, the pipe feeding structure is moved to the corresponding position of the pipe hole, and the base is locked on the arc track by the locking element, so that the base and the power source remain fixed during the pipe feeding process.

[0016] Furthermore, the power source is a winch, which includes a drum, and the connecting cable is wound around the drum; the winch drives the drum to wind up the connecting cable, and the connecting cable pulls the limiting component to apply force to the pipe, and the pushing process is continuous and stable.

[0017] Furthermore, the guide seat includes a limiting plate located on the lower surface of the arc-shaped track and a pressing plate located on the upper surface of the arc-shaped track, and the limiting plate and the pressing plate together form a sliding channel for the arc-shaped track to pass through.

[0018] The locking component includes a first locking rod and a second locking rod that pass through the two sides of the limiting plate. Each side of the pressure plate has a threaded hole. The ends of the first locking rod and the ends of the second locking rod are respectively provided with external threads that match the threaded holes. After tightening, they respectively abut against the two sides of the arc-shaped track, locking the guide seat onto the arc-shaped track.

[0019] Furthermore, the rotating connector includes an upper connector, a lower connector, and a ball bearing located between the upper connector and the lower connector. The upper connector is fixedly connected to the base, and the lower connector is fixedly connected to the guide seat. The base rotates relative to the guide seat about a vertical axis via the ball bearing.

[0020] Furthermore, in step S2, a position monitoring device is set on the arch corresponding to each pipe hole position; in step S4, when the pipe delivery structure is moved along the arc track, when the pipe delivery structure moves to the position corresponding to the pipe hole, the position monitoring device sends a sensing signal, and the operator stops moving the pipe delivery structure according to the sensing signal.

[0021] The beneficial effects of this invention are as follows: The pipe delivery method for a pipe roof in a tunnel arch system disclosed in this invention involves first setting up the arch at a pre-set tunnel opening and reserving pipe holes, then arranging the arc-shaped track along the curvature of the arch in one go. This ensures that the movement trajectory of the pipe delivery structure is consistent with the distribution trajectory of each pipe hole, allowing the pipe to be pushed at a consistent angle at each hole. The pushing direction is constrained by the pipe holes throughout the process, effectively avoiding pipe bending and deformation caused by angle deviation, thus ensuring the pushing quality and subsequent grouting effect. The pipe delivery structure moves along the track hole by hole, requiring only one setup to complete the process. The continuous pipe feeding operation across all pipe holes eliminates the need for repeated platform construction and machinery position adjustments for each hole. Switching between holes is convenient and the connections are tight, significantly improving construction efficiency, reducing the need for temporary facilities, and lowering material and labor costs. The power source applies force to the pipe through connecting cables and limiting components, ensuring stable and controllable driving force and smooth pipe advancement. This avoids pipe deformation caused by uneven force application during manual pushing or bucket pushing. The entire method has clear steps, is easy to operate, does not rely on specific large equipment, and is suitable for the construction needs of multiple pipe sheds at the tunnel arch. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0023] Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] Figure 2 This is a schematic diagram of the power source of the present invention;

[0025] Figure 3 This is a schematic diagram of the guide seat of the present invention;

[0026] Figure 4 This is a schematic diagram of the rotating connector of the present invention. Detailed Implementation

[0027] Figures 1-4 The figure shows a schematic diagram of the pipe feeding equipment used in the method of the present invention. The pipe feeding method applied to the arch arch at the tunnel entrance in this embodiment includes the following steps:

[0028] S1. An arch 1 is erected at a pre-set opening, and the arch 1 has several pipe holes 5 along its curvature.

[0029] Each pipe hole 5 is evenly distributed along the arc-shaped line of the end face of the arch 1. The number and position of the pipe holes 5 are determined according to the number of pipes 7 to be inserted in the construction requirements. During the subsequent pipe delivery process, the pipe holes 5 limit and guide the advancement direction of the pipes 7, so that the pipes 7 can stably enter the arch 1 in the predetermined direction.

[0030] S2. A pipe-feeding device is installed on the arch 1. The pipe-feeding device includes an arc-shaped track and a pipe-feeding structure. The arc-shaped track is set on the outer end face of the arch 1 along the curvature of the arch 1. The pipe-feeding structure is slidably set on the arc-shaped track.

[0031] In this embodiment, the arc-shaped track includes two parallel arc-shaped rails, a first arc-shaped rail 4 and a second arc-shaped rail 2, both of which are arc-shaped and located in the same plane. The first arc-shaped rail 4 is a curved guide rod, mainly serving as an auxiliary guide. It has a simple structure, is lightweight, and is easy to bend and form along the curvature of the arch 1. The second arc-shaped rail 2 is a steel guide rail, which includes an I-shaped flange at its top. The I-shaped structure at the top serves as a sliding fit track surface, with high bending stiffness and strong load-bearing capacity. The load is stably transferred to the outer side near the opening of the arch 1 through the I-beams arranged at intervals towards the arch 1. The two rails slide fit with the guide seats located on the upper and lower sides of the pipe delivery structure, respectively, forming a limiting constraint on the base 6 from both sides. This ensures that the base 6 maintains the correct posture when moving along the arc-shaped path, avoiding skewing, jamming, and shaking caused by the center of gravity shift or uneven force under single-rail support. At the same time, both rails are detachably assembled to the arch 1 by bolts, making installation and disassembly convenient. After construction, they can be removed and reused, reducing construction costs. The arc-shaped track is set along the curvature of the arch 1, so that the moving trajectory of the pipe delivery structure is consistent with the distribution trajectory of each pipe hole 5. During the movement, the pipe delivery structure always maintains a corresponding distance from the end face of the arch 1. When the base 6 drives the power source 3 to move along the track hole by hole, the pipe 7 can be aligned at a consistent angle at each pipe hole 5. The pushing angle is stable, avoiding bending and deformation of the pipe 7 due to angle deviation, and ensuring the pushing quality.

[0032] The pipe feeding structure includes a base 6, a power source 3, and a limiting member 9. The power source 3 is located on the base 6, and the base 6 is slidably mounted on an arc-shaped track.

[0033] The pipe delivery structure also includes guide seats, and the base 6 is slidably connected to the arc-shaped track via the guide seats. There are two sets of guide seats, which are slidably engaged with the first arc-shaped track 4 and the second arc-shaped track 2, respectively, and the base 6 is located between the two sets of guide seats. Each set of guide seats includes a limiting plate 15 located on the lower surface of the corresponding arc-shaped track and a pressing plate 17 located on the upper surface of the corresponding arc-shaped track. The two are detachably assembled by bolts. The limiting plate 15 and the pressing plate 17 form a sliding channel for the corresponding arc-shaped track to pass through, that is, a sliding sleeve for sliding along the corresponding arc-shaped track. The arc-shaped track is confined within the sliding channel, and the guide seat will not detach from the track when sliding along the track. The pressing plate 17 and the limiting plate 15 clamp the track from above and below, so that the guide seat can maintain a stable engagement with the track when bearing the gravitational load of the base 6 and the power source 3. The pressure plate 17 is provided with sliders 16 on both sides of the arc-shaped track, which slide in cooperation with the corresponding arc-shaped track. When the guide seat slides along the track, the sliders 16 contact the track, reducing the frictional resistance between the pressure plate 17 and the track, so that the guide seat slides smoothly.

[0034] The guide seat is equipped with a locking element for locking the base 6 at any position on the track. The locking element includes a first locking rod 14 and a second locking rod 19 that pass through the two sides of the limiting plate 15. The sliders 16 on both sides of the pressure plate 17 are each provided with threaded holes. The ends of the first locking rod 14 and the ends of the second locking rod 19 are respectively provided with external threads that match the threaded holes. After tightening, they respectively abut against the two sides of the corresponding arc-shaped rail, locking the guide seat onto the track.

[0035] The pipe feeding structure also includes a rotating connector, which is located between the base 6 and the guide seat. Its rotation axis is vertical, allowing the base 6 to rotate relative to the guide seat around the vertical axis. Because the arc-shaped track extends in an arc, the relative angle between the base 6 and the track changes as the base 6 moves to different positions. The rotating connector allows the base 6 to adjust its angle according to the curvature of the path, preventing jamming when the base 6 moves along the arc and ensuring smooth sliding of the pipe feeding structure. A connecting plate 18 is bolted to the upper surface of the pressure plate 17, making the overall structure of the guide seat more stable and providing a mounting base for the rotating connector.

[0036] The rotating connector includes an upper flange 21 and a lower flange 20. The upper flange 21 is fixedly connected to the base 6, and the lower flange 20 is fixedly connected to the connecting plate 18. An upper retainer 24 is integrally formed on the lower surface of the upper flange 21, and an upper raceway is provided within the upper retainer 24. A lower retainer 26 is integrally formed on the upper surface of the lower flange 20, and a lower raceway is provided within the lower retainer 26. The upper and lower raceways together form a ball bearing receiving channel, which is divided into several positioning through holes by a partition. Each positioning through hole is fitted with a steel ball 25, allowing each steel ball 25 to be independently positioned and roll evenly. The base 6 rotates relative to the guide seat around a vertical axis via the steel balls 25. The steel balls 25 convert the relative rotation between the base 6 and the guide seat from sliding friction to rolling friction, resulting in low rotational resistance. When the base 6 moves on the arc-shaped track, it can smoothly adjust its angle and avoid jamming. The upper flange 21 and the lower flange 20 have threaded holes evenly distributed around their circumference, which are threaded to the base 6 and the connecting plate 18 respectively by locking nuts 22. The lower flange 20 has a lower through hole in its center, and the upper flange 21 has an upper through hole in its center. The center bolt 23 passes through the two through holes from bottom to top and is threaded onto the locking nut 22 to adjust the preload on the steel ball 25, eliminate assembly gaps, and improve rotational smoothness.

[0037] The base 6 is equipped with a support seat 12, the upper surface of which is an arc-shaped mounting surface. The power source 3 is fixed to this arc-shaped mounting surface by bolts. The arc-shaped mounting surface of the support seat 12 is adapted to the bottom shape of the power source 3, providing stable mounting support for the power source 3. The power source 3 remains in a fixed position during pipe feeding and will not be displaced due to vibration or traction reaction force, ensuring stable power output. One side of the base 6 has an arc-shaped surface, which is used to slide in contact with the surface of the pipe 7 to guide the pipe 7 during the pushing process.

[0038] The power source 3 is specifically any electric winch in the prior art. The power source 3 includes a drum shaft 13, the axis of which is arranged horizontally. The power source 3 is connected to the limiting member 9 via a connecting cable 8, which is wound around the drum shaft 13. The limiting member 9 is located on one side of the end face of the drum shaft 13, and there is a certain distance between it and the drum shaft 13. The limiting member 9 is sleeve-shaped and is sleeved on the outer end of the preset tube 7 during use. The outer surface of the limiting member 9 is provided with an outwardly protruding blocking ring rib, and the outer surface of the limiting member 9 is also provided with a winding ring groove 10 located outside the blocking ring rib for accommodating the connecting cable 8. The connecting cable 8 is placed in the winding ring groove 10 and wound around the outer surface of the limiting member 9, and is axially limited by the blocking ring rib.

[0039] In this embodiment, step S2 further includes setting infrared sensors on the arch 1 corresponding to the positions of each pipe hole 5. The infrared sensors are connected to the alarm signal and are used to monitor whether the base 6 has reached the corresponding position of the pipe hole 5.

[0040] S3. Insert the first end of the pipe 7 to be pushed into the corresponding pipe hole 5 on the arch 1, and connect the pipe feeding structure to the pipe 7; apply force to the pipe 7 through the pipe feeding structure, and drive the pipe 7 to be gradually pushed into the arch 1 along the direction of the pipe hole 5.

[0041] Specifically, the pipe delivery mechanism is moved along the arc-shaped track to the corresponding position of the pipe hole 5 to be constructed. When the base 6 moves to the corresponding position of the pipe hole 5, the infrared sensor sends the detected obstruction information to the microprocessor. The microprocessor then issues a command to sound the alarm on the side, reminding the operator that the base 6 has reached the position of the pipe hole 5, at which point the operator can stop moving the base 6. Tighten the first locking rod 14 and the second locking rod 19 so that they symmetrically press against the track from both sides. The guide seat is locked in the current track position, and the base 6 and the power source 3 remain fixed during the pipe delivery process, ensuring stable transmission of the pushing force and preventing the sliding of the base 6 from affecting the pushing angle of the pipe 7.

[0042] The first end of the pipe 7 is inserted into the pipe hole 5, and the pipe hole 5 limits and guides the advancement direction of the pipe 7. The limiting member 9 is sleeved on the outer end of the pipe 7, and the connecting cable 8 is placed in the winding ring groove 10 and wound around the outer surface of the limiting member 9. It is axially limited by the blocking ring rib to prevent the connecting cable 8 from slipping off the limiting member 9 during the pulling process, thus ensuring the reliability of power transmission.

[0043] The power source 3 drives the drum shaft 13 to wind up the connecting cable 8, applying force to the limiting member 9 and thus driving the pipe 7 to gradually penetrate deeper into the arch 1 along the direction of the pipe hole 5. During the pushing process, the head end of the pipe 7 is always located inside the pipe hole 5. The arc-shaped surface on the side of the base 6 provides support for the middle and rear part of the pipe 7. The pipe 7 slides along this arc-shaped surface during forward advancement. This arc-shaped surface and the pipe hole 5 together limit the pushing direction of the pipe 7, ensuring that the pipe 7 enters the arch 1 stably in a straight line and preventing the pipe 7 from bending due to force deviation during the pushing process. The driving force of the power source 3 is stable and controllable, the winding speed of the connecting cable 8 is uniform, and the pushing process of the pipe 7 is smooth, avoiding bending and deformation of the pipe 7 caused by uneven force application during manual pushing or bucket pushing.

[0044] S4. After pushing one pipe 7, move the pipe feeding structure along the arc track to the corresponding position of the next pipe hole 5, and repeat S3 until the pipe feeding operation of all pipe holes 5 is completed.

[0045] Specifically, after pushing one pipe 7, the first locking rod 14 and the second locking rod 19 are released to release the lock between the guide seat and the arc-shaped track. The pipe delivery structure is moved along the arc-shaped track to the corresponding position of the next pipe hole 5. During the movement, the two sets of guide seats slide synchronously along the first arc-shaped track 4 and the second arc-shaped track 2, respectively, forming a limiting constraint on the base 6 from both sides. This ensures that the base 6 maintains the correct posture when moving along the arc-shaped path, avoiding skewing, jamming, and shaking caused by the center of gravity shift or uneven force under single-track support. At the same time, the base 6 rotates relative to the guide seat around the vertical axis through the rotating connector to adapt to the curvature change of the arc-shaped track, preventing jamming when the base 6 moves on the arc and ensuring smooth sliding of the pipe delivery structure. After moving to the corresponding position of the next pipe hole 5, step S3 is repeated until the pipe delivery operation of all pipe holes 5 is completed. After all operations are completed, the arc-shaped track is removed from the arch 1.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for pipe delivery in a pipe roof for a tunnel arch, wherein the arch has a plurality of pipe holes along its curvature, characterized in that: Includes the following steps: S1. An arch is erected at the pre-set opening, and the arch is provided with several pipe holes along its curvature; S2. A pipe-feeding device is installed on the arch, the pipe-feeding device including an arc track and a pipe-feeding structure, the arc track is installed on the arch along the curvature of the arch, and the pipe-feeding structure is slidably installed on the arc track. S3. Insert the first end of the pipe to be pushed into the corresponding pipe hole on the arch and connect the pipe feeding structure to the pipe; apply force to the pipe through the pipe feeding structure to drive the pipe to be gradually pushed into the arch along the direction of the pipe hole. S4. After completing the pushing of one pipe, move the pipe feeding structure along the arc track to the corresponding position of the next pipe hole, and repeat S3 until the pipe feeding operation of all pipe holes is completed.

2. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 1, characterized in that: The pipe feeding structure includes a base, a power source, and a limiting member. The power source is located on the base, and the base is slidably mounted on an arc-shaped track. In step S3, the limiting member is sleeved on the outer end of the pipe. The power source is connected to the limiting member via a connecting cable. The power source drives the connecting cable to rewind, thereby applying force to the limiting member and pushing the pipe into the arch.

3. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 2, characterized in that: The arc-shaped track includes two parallel and spaced-apart first and second arc-shaped tracks, both of which are in the same plane.

4. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 3, characterized in that: The pipe feeding structure also includes guide seats, which are in two sets and slide in cooperation with the first arc-shaped rail and the second arc-shaped rail respectively. The base is located between the two sets of guide seats. In step S4, when the pipe feeding structure moves along the arc-shaped rail, the two sets of guide seats slide synchronously along the first arc-shaped rail and the second arc-shaped rail respectively, forming a limiting constraint on the base from both sides.

5. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 4, characterized in that: The pipe feeding structure also includes a rotating connector, which is located between the base and the guide seat, and its rotation axis is set in the vertical direction. In step S4, when the pipe feeding structure is moved along the arc track, the base rotates relative to the guide seat around the vertical axis through the rotating connector to adapt to the curvature change of the arc track and avoid the base from getting stuck when moving on the arc.

6. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 4, characterized in that: The guide seat is equipped with a locking element; in step S3, before the end of the pipe is inserted into the pipe hole, the pipe feeding structure is moved to the corresponding position of the pipe hole, and the base is locked on the arc track by the locking element, so that the base and the power source remain fixed during the pipe feeding process.

7. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 2, characterized in that: The power source is a winch, which includes a drum, and the connecting cable is wound around the drum. The winch drives the drum to wind up the connecting cable, and the connecting cable pulls the limiting component to apply force to the pipe, and the pushing process is continuous and stable.

8. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 4, characterized in that: The guide seat includes a limiting plate located on the lower surface of the arc-shaped track and a pressing plate located on the upper surface of the arc-shaped track. The limiting plate and the pressing plate together form a sliding channel through which the arc-shaped track passes. The locking component includes a first locking rod and a second locking rod that pass through the two sides of the limiting plate. Each side of the pressure plate has a threaded hole. The ends of the first locking rod and the ends of the second locking rod are respectively provided with external threads that match the threaded holes. After tightening, they respectively abut against the two sides of the arc-shaped track, locking the guide seat onto the arc-shaped track.

9. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 5, characterized in that: The rotating connector includes an upper connector, a lower connector, and a ball bearing located between the upper connector and the lower connector. The upper connector is fixedly connected to the base, and the lower connector is fixedly connected to the guide seat. The base rotates relative to the guide seat about a vertical axis via the ball bearing.

10. The pipe-feeding method for a pipe roof for arching tunnel openings according to claim 1, characterized in that: In step S2, a position monitoring device is set on the arch corresponding to each pipe hole position; in step S4, when the pipe delivery structure is moved along the arc track, when the pipe delivery structure moves to the position corresponding to the pipe hole, the position monitoring device sends a sensing signal, and the operator stops moving the pipe delivery structure according to the sensing signal.

Images