JP3542108B2 - Underground pipe laying method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an underground pipe laying method, and more particularly, to an underground pipe laying technique for simultaneously digging and piping in a technique of digging an arbitrary curved road from the ground to the ground.
[0002]
[Prior art]
Conventionally, a small pilot hole having an arbitrary curved path from the ground to the ground is drilled using a drill string, and the pilot hole is expanded by a reamer or the like, and a casing pipe is introduced into the expanded hole to form an underground pipe. There is a technology to form a road. For example, U.S. Pat. No. 3,878,903 discloses a technique for drilling a hole having an arbitrary curved shape from the ground surface using a drill string into the ground. An arc propulsion technique in which a drill string is pulled back by attaching a reamer to the tip of the drill string in the hole), the pilot hole is expanded in this pulling-back step, and then a casing pipe is pushed or pulled into this hole to lay an underground pipe. Is disclosed. In such prior art, laying an underground pipe requires four steps of pilot hole excavation, reamer expansion, reaming, and underground pipe pulling, or three steps of reaming and expansion of the underground pipe. I needed it.
[0003]
In such prior art, drilling is first performed using a drill string for drilling. The drill string extends and extends the drill pipe sequentially, but the drill pipe is a thick pipe or a hollow rod dedicated to drilling, and its connection part transmits the thrust and the male and female threads which are tightly connected to each other to transmit the rotational force. And a contact end face. This connection part is designed to be repeatedly attached and detached, equipped with male and female threads with strong threads with coarse pitch, enabling connection and disconnection of drill pipe with a small rotation and transmitting large rotational torque It has the function to do. The male and female screws are connected to form a drill string, and the connection structure is designed for repeated use. Drill pipes have a diameter of 23/8 "(about 60 mm) to 65/8" (about 170 mm) depending on the purpose, and more specifically, 13 "(about 330 mm), 20" ( (About 510 mm).
[0004]
On the other hand, a casing pipe is a pipe that originally has a lining function to protect the wall surface of the underground hole, and the connection part has a fine pitch screw structure via a sleeve-like coupling, which prevents leakage. It has a tight structure to prevent. Screws are not of the type transmitting large rotational torques and usually do not have a mechanism for transmitting strong thrust. This screw is not of the type that repeatedly attaches and detaches, but is connected as a lining tube, and has a structure that emphasizes the sealing performance of the joint.
[0005]
[Problems to be solved by the invention]
The present invention has developed a technique of excavating an underground hole using a casing pipe and simultaneously constructing an underground pipe, instead of drilling using a drill pipe. It is an object of the present invention to provide a method for performing the middle piping in one step.
[0006]
[Means for Solving the Problems]
The present invention relates to laying an underground pipe having an arbitrary curved path from the ground to the ground, and using a coupling having a screw structure for transmitting a large rotational torque and a thrust and a thrust transmitting portion, using a casing. The pipes are connected to each other, and a drilling tool and a path measuring device used for arc-shaped propulsion are attached to the tip of the casing pipe at the tip of the casing pipe, and excavation is performed forward while transmitting rotational torque and thrust to the casing pipe. An underground pipe laying method characterized in that the pipe is used as it is as an underground pipe. The method of the present invention does not use a drill string connected with a drill pipe dedicated to drilling. Instead, a casing pipe is used. The casing pipe is not originally designed to transmit a large rotational torque and thrust. However, couplings with improved joint efficiency have also been developed, and couplings having a screw structure with imparted torque transmission and having a metal-contacting torque shoulder have also been developed. The present invention has been completed by finding that appropriate rotational torque and thrust can be transmitted by using those couplings and casing pipes having appropriate dimensions and structures.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the related art will be described. FIG. 9 shows an underground hole drilling process using a conventional drill string 20. An excavation hole 52 is excavated from the ground surface 51 into the underground 50 using an excavator (not shown). The drilling tool has a drill bit 1 at the leading end, a mud motor 2 for driving the drill bit 1 attached thereto, and a vent sub 3 attached to the back thereof. A measuring instrument 4 is attached to the rear, and a drill string 20 is attached via a non-magnetic collar 5. The drill string 20 sequentially connects the drill pipes and enters the drill hole. As shown in the cross section of the connecting portion 21 in FIG. 11, the drill string 20 has a screw 22 having a coarse pitch for transmitting the rotational torque and a large thread, and the surface 23 for transmitting the thrust. Can be transmitted.
[0008]
FIG. 10 shows that after drilling a drill hole 52 with the drill string 20, a reamer 31 is attached to the tip in the return process of the drill string 20, and the drill string 20 is expanded while rotating the drill string 20 using the reamer 31. A step of forming a hole 53 and simultaneously pulling a pipe 33 through a swivel 32 to construct an underground pipe is shown.
[0009]
FIG. 1 shows a method of laying an underground pipe according to an embodiment of the present invention, in which a casing pipe 10 is used instead of the drill string 20 in FIG. The bit 1, mud motor 2, vent sub 3, measuring device 4, and non-magnetic collar 5 are the same as those in FIG. As shown in FIG. 1, the casing pipe 10 can be piped underground in one step at the same time as the formation of the excavation hole.
[0010]
FIG. 2 shows an example of the structure of the excavating tool. A seal 13 is provided at the tip of a tip casing 11 to cover the excavating tool, and a fixing rib 14 is provided inside to fix the excavating tool and the casing 11. ing. FIG. 3 shows another example, in which a non-magnetic casing 12 and a casing pipe 10 are connected to the rear of the vent sub 3. FIG. 4 shows a drilling tool that does not use the mud motor 2, and is used in a soil condition where drilling can be performed only with a jet. 5 to 8 exemplify the structure of the coupling 41 of the casing pipe 10 designed to transmit the thrust. FIG. 5 exemplifies a coupling 41 provided with a trapezoidal screw 42 and provided with thrust transmitting portions 43 and 44, and FIG. 6 shows an enlarged detailed view of a portion A thereof. FIG. 7 illustrates another coupling 41, and illustrates a structure of a connecting portion between the coupling 41 having the thrust transmitting portions 45 and 46 and the casing pipe 10, and FIG. is there. The present invention can be implemented by selecting the coupling 41 having such a thrust transmitting function and the casing pipe 10 having an appropriate diameter and thickness.
[0011]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, it became possible to simultaneously lay underground piping in one process of excavating an underground hole.
[Brief description of the drawings]
FIG. 1 is a side view of an excavation unit according to an embodiment.
FIG. 2 is an explanatory diagram of a drilling tool according to an embodiment.
FIG. 3 is an explanatory diagram of the excavating tool according to the embodiment.
FIG. 4 is an explanatory diagram of a drilling tool according to the embodiment.
FIG. 5 is a sectional view of a connecting portion of the casing pipe of the embodiment.
FIG. 6 is an enlarged view of a portion A in FIG. 5;
FIG. 7 is a sectional view of a connection portion of the casing pipe of the embodiment.
FIG. 8 is an enlarged view of a portion B in FIG. 7;
FIG. 9 is a side view showing a conventional excavation step.
FIG. 10 is an explanatory view of a conventional hole expanding step.
FIG. 11 is an explanatory view of a connection portion of a conventional drill string.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 drill bit 2 mud motor 3 vent sub 4 measuring instrument 5 non-magnetic collar 10 casing pipe 11 tip casing 12 non-magnetic casing 13 seal 14 fixing rib 20 drill string 21 connecting part 22 screw 23 contact surface 31 reamer 32 swivel 33 pipe 41 Coupling 42 Screws 43, 44, 45, 46 Thrust transmission unit 50 Underground 51 Ground surface 52 Excavation hole 53 Enlarged hole

Claims (1)

When laying an underground pipe with an arbitrary curved path from the ground to the ground , the casing pipes are connected to each other using a coupling with a screw structure for transmitting large rotational torque and thrust and a thrust transmitting part At the end of the casing pipe, an excavating tool and a path measuring device used for arc-shaped propulsion are attached to the end of the casing pipe and excavated forward while transmitting rotational torque and thrust to the casing pipe. An underground pipe laying method, characterized in that:

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