JP3779035B2 - Excavator and pipe drawing method using it - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an excavator for expanding a pilot hole that has been excavated in advance and laying a main pipe, and a pipe retracting method using the excavator, and more particularly to improving work efficiency when laying a long distance.
[0002]
[Prior art]
In order to dig down the obstacles such as rivers with a smooth curve and lay various pipes such as gas pipes over a long distance, the pilot pipe is dug from the start side to the arrival side and penetrates the pilot hole, and the arrival side The expansion bit is connected to the tip of the pilot pipe that reaches the point, and rotates while pulling the pilot pipe toward the starting side, and this rotation rotates the expansion bit to expand the pilot hole to a larger diameter than the main pipe. However, a method of drawing the main pipe or a method of drawing the main pipe after expanding the hole and separating the main pipe drawing process is adopted. The size of the hole to be pulled in to pull in the main pipe depends on the surrounding soil, but expands to 1.2 to 1.5 times the outer diameter of the pipe to be pulled in. When this hole is expanded, a large amount of bentonite mud is sprayed and mixed with the earth and sand to form mud to secure the hole wall. If the expansion process and the main pipe drawing process are separated, the high-pressure bentonite mud water is sprayed to ensure the hole wall and the mud water is used as a lubricant when the main pipe is drawn in the same way. Then pull the main. When this muddy water and earth and sand are separated and deposited, it becomes impossible to stir and pull the main pipe, so the whole main pipe is drawn at once while continuously spraying and stirring the muddy water.
[0003]
[Problems to be solved by the invention]
When the pilot hole is expanded as described above, it is expanded to a size 1.2 to 1.5 times the outer diameter of the main pipe using a hole expanding machine, and bentonite does not harden. For example, the pipe is laid under the road There was a risk that the sediment around the pipe would sink.
[0004]
Also, in order to draw the entire tube at once, it is necessary to make a long tube in advance, and a space with a length corresponding to the long tube to be drawn to the drawing side is required. Was not easy.
[0005]
In addition, when a space with a length corresponding to the pipe to be pulled in cannot be secured by the method of pulling in the main pipe while expanding the hole, the pipe is welded and pulled in, so the hole is expanded when the pipe is welded. Had to stop.
[0006]
Further, since the hole is expanded to 1.2 to 1.5 times the outer diameter of the main pipe, the amount of earth and sand to be excavated increases, and its transport method has been a problem in urban areas.
[0007]
The present invention has been made to remedy such disadvantages, and an excavator capable of preventing the settlement of sediment around the pipe and quickly laying a long-distance pipe even in an urban area, and a pipe using the excavator The purpose is to provide a retraction method.
[0008]
[Means for Solving the Problems]
The excavator according to the present invention has an excavation head and a slide tube, the excavation head has a connecting portion with a drill pipe for excavating a pilot hole at a tip portion, and a rear end portion of the excavator through a bearing. The sliding tube has a sliding expansion and contraction-type pipe joint that expands and contracts in a plurality of stages, and is connected to a tube in which a rear end portion is embedded.
[0009]
In the pipe drawing method according to the present invention, a drill head is attached to the tip of the drill pipe from the start side to cut the ground to form a pilot hole, and when the tip of the drill pipe reaches the arrival side, the pilot hole is formed at the tip. Connected to the tip of the drill pipe is a drilling head connected to a slide pipe having a sliding expansion joint that has a connecting part with a drill pipe for drilling, and a rear end part that expands and contracts in multiple stages via a bearing Then, while pulling the drill pipe on the start side, the drilling head is rotated to expand the pilot hole and advance, and the slide head is gradually pulled out by the advancement of the drilling head. When the rear pipe is joined to the pipe buried in the rear end of the sliding pipe or the pipe joined to the sliding pipe, the sliding pipe moves forward when the excavation head advances by the sliding span length of the sliding pipe. Slide the tube joined to And repeating the reducing the sliding telescopic fitting in a plurality of stages.
[0010]
When the sliding expansion / contraction type pipe joint of the slide tube is pushed in and reduced, it is preferable that the sliding material is ejected to the outside from each sliding expansion / contraction type pipe joint.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The excavator of the present invention has an excavation head and a sliding tube. The excavation head has a connecting portion with a drill pipe for excavating a pilot hole at the front end portion, and the rear end portion is connected to the sliding tube via a bearing. The sliding tube has a plurality of sliding tubes, a front tube whose tip is connected to the excavation head, and a rear tube and an inner tube that connect the embedded tube, and a plurality of sliding tubes, a front tube, and a rear tube. A sliding telescopic pipe joint that expands and contracts in stages is formed.
[0012]
When laying pipes underground using this excavator, a drill head is attached to the tip of the drill pipe from the starting side to cut through the ground to form a pilot hole, and the tip of the drill pipe reaches the reaching side. When reaching, connect the drilling head to the tip of the drill pipe. In this state, the drilling head is rotated while pulling the drill pipe on the start side, and the pilot hole is expanded to advance. When the excavator cuts substantially into the ground, the rear end of the sliding pipe is stopped and the excavation head moves forward, so that a plurality of stages of sliding telescopic pipe joints are gradually pulled out. When the slide expansion and contraction type pipe joint of the plurality of stages of the sliding pipe is gradually pulled out, a pipe embedded in the rear end portion of the stopped sliding pipe is welded and joined. When the sliding expansion and contraction type pipe joint of the sliding pipe is gradually pulled out in this way, the sliding pipe and the pipe are welded. Therefore, when joining the pipe, the drilling head is expanded and the hole is advanced without stopping. Can be made.
[0013]
When the excavation head moves forward and the sliding tube is pulled out to the maximum, the tube joined to the sliding tube is pushed into the ground with the main pusher installed on the arrival side, and the sliding expansion joint of the sliding tube is pushed in. to shrink. When the sliding expansion / contraction fitting of the sliding tube is pushed in and reduced, muddy water adhering to the sleeve surface of the sliding expansion / contraction fitting can be removed by blowing the lubricant from the sliding expansion / contraction fitting. The expansion joint can be pushed in without resistance.
[0014]
When the sliding expansion / contraction fitting of the sliding pipe is pushed in to the maximum and the excavation head advances by one pipe, the pushing of the pipe stops and the excavation head advances while pulling out the sliding expansion / contraction fitting of the sliding pipe. The next pipe is welded to the pipe joined to the sliding pipe. In this way, the pipes to be pulled in are sequentially joined while repeatedly sliding and pushing the sliding expansion and contraction type pipe joint of the sliding pipe, and the pilot hole is expanded by advancing without stopping the excavation head when joining the pipes. .
[0015]
【Example】
FIG. 1 is a sectional view showing the configuration of an excavator according to an embodiment of the present invention. As shown in the figure, the excavator 1 has an excavation head 2 and a sliding tube 3. The excavation head 2 has a connecting portion 21 with a drill pipe 4 for excavating a pilot hole at a tip portion, and a rear end portion is connected to the sliding tube 3 via a bearing 22. The sliding tube 3 includes a plurality of sliding cylinders 31, a front cylinder 32, a rear cylinder 33, and an inner cylinder 34 whose front ends are connected to the excavation head 2. The sliding cylinder 31 is formed with a stepped outer diameter smaller than the outer diameter of the rear end portion, and the distal end portion forms a sleeve 35 of a sleeve-type expansion joint having a fixed length. A guide portion 36 for guiding the sleeve 35 is provided on the inner surfaces of the rear end portion of the sliding tube 31 and the rear end portion of the front tube 32. The distal end portion of the rear cylinder 33 also forms a sleeve 35 of a sleeve-type expansion joint having a certain length. As shown in the partial sectional view of FIG. 2, a holding portion 351 having an outer diameter slightly smaller than the inner diameter of the guide portion 36 is provided at the tip of the sleeve 35 of the sliding cylinder 31 and the rear cylinder 33. The seal member 352 formed of rubber or the like to which the guide portion 36 is fitted is fixed. A stopper 353 is provided at a rear portion of the presser part 351 at a predetermined interval, and a lubricant supply hole 354 is provided between the presser part 351 and the stopper 353. At the rear ends of the guide portions 36 of the sliding cylinder 31 and the front cylinder 32, a ring-shaped locking portion 361 that engages with the stopper 353 is provided. A valve 362 made of a rubber ring is attached to the locking portion 361. The front cylinder 32, for example, the two sliding cylinders 31 and the rear cylinder 33 constitute a slide expansion / contraction type pipe joint that expands and contracts in three stages. The inner cylinder 34 has substantially the same length as that when the three-stage sliding expansion / contraction type pipe joint including the front cylinder 32, the two sliding cylinders 31 and the connection cylinder 33 is pushed in to the maximum, The sliding cylinder 31 and the rear cylinder 33 are coaxially attached to the front cylinder 32. A lock pin actuator 341 for locking the inner cylinder 34 to the rear cylinder 33 is provided at the rear end portion of the inner cylinder 34.
[0016]
A lubricant supply / supply pipe 6 having a check valve 5 is connected to the lubricant supply hole 354 of the sleeve 35. Further, a sludge pipe 8 having an expansion pipe joint 7 is connected to the excavation head 2.
[0017]
The operation when the small-diameter pipe is drawn into the ground using the excavator 1 configured as described above will be described with reference to the construction process diagrams of FIGS.
[0018]
First, as shown in FIG. 3A, a drill head is attached from the starting shaft 10 to the tip of the drill pipe 4 and the pilot pipe is formed by advancing the ground 12 while rotating the drill pipe 4 by the rig 11. . When this pilot hole is formed, for example, an electric current is passed through a cable stretched on the ground to generate a magnetic field, which is detected by a magnetic sensor installed behind the drill head, so that the tip of the drill pipe 4 is accurately positioned. Can be positioned. When the tip of the drill pipe 4 reaches the reaching shaft 13, as shown in FIGS. 3 (b) and 3 (c), a drilling and pipe drawing process is performed by the excavator 1. In the hole expansion and pipe drawing process, the drill head is removed from the tip of the drill pipe 4 reaching the reaching shaft 13, and the tip of the drill pipe 4 is connected to the connecting portion 21 of the drilling head 2 of the excavator 1. Then, as shown in FIG. 1, the lock pin actuator 341 provided on the inner cylinder 34 of the excavator 1 is locked and the inner cylinder 34 is locked to the rear cylinder 33 to push the sliding tube 3 to the maximum. In a fixed state, while the muddy water is pumped from the start shaft 10 to the drill pipe 4, the drill pipe 4 is rotated by the start shaft 10 and the drill head 2 is rotated, and the drill pipe 4 is pulled to the start shaft 10 side. The excavation head 2 is drawn into the ground 12 while mixing and stirring the excavated earth and sand and the muddy water sent from the drill pipe 4. The mixed mud is discharged through a mud pipe 8 in the excavator 1. As shown in FIG. 4A, when the excavator 1 cuts substantially into the ground, the lock pin actuator 341 provided on the inner cylinder 34 is unlocked and cut. When the lock pin actuator 341 is unlocked and machined, the three-stage sliding telescopic pipe joint is gradually pulled out with the rear cylinder 33 of the sliding tube 3 stopped. When the three-stage sliding expansion type pipe joint of the sliding pipe 3 is gradually pulled out, the pipe 14 drawn into the stopped rear cylinder 3 is welded and joined. When the three-stage sliding expansion / contraction type pipe joint of the sliding pipe 3 is gradually pulled out in this way, the pipe 14 is welded to the rear cylinder 33 of the sliding pipe 3, and therefore excavation is performed when the pipe 14 is joined. The hole can be expanded without stopping the head 2. Further, when the three-stage sliding expansion joint of the sliding tube 3 is gradually pulled out, the sleeve 35 and the guide are connected from the sliding material supply / supply tube 6 connected to the sleeve 35 of the sliding tube 31 and the rear tube 33. Lubricant is supplied between the portions 36, and the supplied lubricant is blown out from the valve 362 to prevent muddy water from entering between the sleeve 35 and the guide portion 36.
[0019]
When the tube 14 is connected to the sliding tube 3 and the excavation head 2 moves forward and the sliding tube 3 is pulled out to the maximum as shown in FIG. 4B, the tube 14 joined to the sliding tube 3 is removed. It pushes into the underground 12 with the main pushing device 15 installed in the reaching shaft 13. By pushing this pipe 14, the three-stage sliding expansion type pipe joint of the sliding pipe 3 is pushed. Further, when the sliding expansion joint of the three stages of the sliding tube 3 is pushed in and reduced, a sliding material is supplied between the sleeve 35 and the guide portion 36 of the sliding cylinder 31 and the rear cylinder 33, and the supplied sliding material is supplied. Since the material is blown out from the valve 362, the earth and sand adhering to the surface of the sleeve 35 can be removed, and the three-stage sliding expansion type pipe joint of the sliding pipe 3 can be pushed in without resistance. When the three-stage sliding telescopic pipe joint of the sliding tube 3 is pushed in to the maximum, the lock pin actuator 341 is locked and the inner cylinder 34 is locked to the rear cylinder 33, and the excavation head 2 is pulled and rotated by the drill pipe 4. While pushing the tube 14. When the excavation head 2 moves forward by one pipe 14, the lock pin actuator 341 is locked, and the three-stage sliding telescopic pipe joint of the sliding pipe 3 is pulled out as the excavation head 2 advances. When the excavation head 2 is moving forward while pulling out the three-stage sliding expansion / contraction-type pipe joint of the sliding pipe 3, as shown in FIG. The pipe 14 is welded and joined. In this way, since the pipe 14 to be pulled in is sequentially joined while repeatedly pulling and pushing the three-stage sliding expansion-type pipe joint of the sliding pipe 3, it is not necessary to stop the excavation head 2 in order to join the pipe 14. The hole expansion and pipe drawing when embedding 14 at a long distance can be performed in a short time. Further, since the pipe 14 is pulled in while the excavation head 2 is advanced, the diameter of the hole expanded by the excavation head 2 may be somewhat larger than the outer diameter of the pipe 14, and the amount of earth and sand to be mixed and stirred can be reduced. At the same time, the sediment around the laid pipe 14 can be prevented from sinking.
[0020]
Although the said Example demonstrated the case where the pipe | tube 14 was directly joined to the excavator 1, when the sliding stroke of the sliding pipe | tube 3 of the excavator 1 is short, as shown in FIG. Two stages may be used to obtain a sliding stroke corresponding to the total length of one pipe 14. Thus, when the sliding stroke according to the full length of one pipe | tube 14 is obtained, the time which welds and joins the pipe | tube 14 and the test | inspection time of a welded joint can fully be taken.
[0021]
When pulling the pipe 14 while expanding the hole with the excavator 1 as described above, if the thrust when pulling the pipe 14 to construct a long distance becomes excessive, the middle of the pipe 14 being pulled An intermediate push pipe may be provided in the part, and the thrust applied to the main pushing device 15 may be divided into a front part and a rear part of the intermediate push pipe.
[0022]
Moreover, although the said Example demonstrated the case where mud water was supplied from the starting shaft 10 through the drill pipe 4, and the mud mixed with the excavated earth and sand was discharged with the mud pipe 8, the mud sent and discharged instead of the mud pipe 8 A pipe may be provided to supply muddy water from the reaching shaft 13 side, and the muddy water mixed with the excavated earth and sand may be discharged to the reaching shaft 13 side.
[0023]
Furthermore, although the said Example demonstrated the case where the starting shaft 10 and the reaching shaft 13 were provided and laying the pipe | tube 14, the pilot hole was directly drilled from the ground surface without providing the starting shaft 10 and the reaching shaft 13, and The pipe 14 may be laid directly from the ground surface.
[0024]
Moreover, although the said Example demonstrated the case where a small diameter pipe | tube was drawn in in the ground, a large diameter pipe | tube can be drawn in similarly. In this case, a swivel joint is provided at the connecting portion 21 of the excavation head 2 with the drill pipe 4, and a rotary drive device such as an electric motor or a hydraulic motor is installed on the excavation head 2, and the excavation head 2 is directly rotated by this rotary drive device. You may do it.
[0025]
【The invention's effect】
As described above, according to the present invention, as the excavating head moves forward, the sliding which is stopped when the multi-stage sliding telescopic pipe joint having the sliding pipe of the excavator is gradually pulled out. Since pipes are welded and joined to each other, and subsequent pipes are welded and joined to pipes joined to sliding pipes, the drilling head can be expanded without stopping when joining the pipes. It can be moved forward, and the hole expansion and pipe drawing when the pipe is embedded at a long distance can be performed in a short time.
[0026]
In addition, since the pipe is pulled in while the excavation head is advanced, the diameter of the hole to be expanded by the excavation head may be somewhat larger than the outer diameter of the pipe, and the amount of earth and sand to be excavated can be reduced. Can be prevented, and the transport and disposal of excavated earth and sand can be simplified.
[0027]
Furthermore, it is only necessary to make the diameter of the hole expanded by the excavation head somewhat larger than the outer diameter of the pipe, so that it is possible to prevent the sediment around the installed pipe from sinking after the installed pipe is installed. It is possible to prevent a road or the like from sinking when laid underneath.
[0028]
Further, since the pipes are sequentially welded and joined while the excavation head is advanced, it is not necessary to prepare a long pipe in advance for long distance construction, and the pipe can be drawn in a small construction space.
[0029]
Furthermore, when the sliding expansion / contraction type fitting of the sliding pipe is pushed in and reduced, mud water adhering to the sleeve surface of the sliding expansion / contraction fitting can be removed by blowing out the sliding material from the sliding expansion / contraction fitting. The sliding telescopic pipe joint can be pushed in without resistance.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of an excavator according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional view of a sliding tube.
FIG. 3 is a construction process diagram when pulling in a pipe.
FIG. 4 is a construction process diagram showing an extended state of the sliding tube when retracted.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Excavator 2 Excavation head 3 Sliding pipe 4 Drill pipe 10 Starting shaft 13 Reaching shaft 14 Pipe 22 Bearing 31 Sliding cylinder 32 Front cylinder 33 Rear cylinder 34 Inner cylinder 35 Sleeve 36 Guide part

Claims (3)

The excavation head has a sliding pipe, the excavation head has a connecting part with a drill pipe for excavating a pilot hole at the tip, the rear end is connected to the sliding pipe via a bearing, An excavator comprising a slide expansion / contraction type pipe joint that expands and contracts in a plurality of stages and is connected to a pipe in which a rear end portion is embedded. A drill head is attached to the tip of the drill pipe from the starting side to drill the ground to form a pilot hole, and when the tip of the drill pipe reaches the arrival side, the connecting portion with the drill pipe that drills the pilot hole at the tip A drilling head connected to a sliding pipe having a sliding expansion and contraction-type pipe joint whose rear end part expands and contracts in multiple stages via a bearing is connected to the tip of the drill pipe, and the drill pipe is pulled on the start side While rotating the excavation head, the pilot hole is expanded and advanced, and when the excavation head advances, the slide expansion and contraction-type joint of the multi-stage of the slide pipe is gradually pulled out. Join the latter pipe to the pipe embedded in the end or the pipe joined to the sliding pipe, and push the pipe joined to the sliding pipe and slide when the excavation head advances by the sliding span length of the sliding pipe Multi-stage sliding telescopic pipe joint of pipe Tube pull method, characterized in that repeated reducing. The pipe drawing-in method according to claim 2, wherein when sliding the plurality of sliding expansion / contraction-type pipe joints of the sliding pipe to reduce the sliding material, the sliding material is ejected from each sliding expansion / contraction-type pipe joint.

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