Large-diameter double-wall drill rod adopting tongue-and-groove socket sealing connection structure
By adopting a large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure, the problems of equipment complexity and operational difficulty in small-diameter pipe jacking technology have been solved. This has enabled stable connection and torque transmission of the drill pipe, adapting to complex terrain operations and reducing construction risks.
Patent Information
- Application Number
- CN202511393320.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-27
- Publication Date
- 2025-11-14
AI Technical Summary
The field of small-diameter pipe jacking technology is characterized by high risks, difficulty in operation, easy pipe blockage, high overall construction costs, and a lack of mature equipment and tools. In particular, the difficulty of operation is increased when setting up grouting pipelines and mud discharge pipelines.
The large-diameter double-walled drill rod adopts a tongue-and-groove socket sealing connection structure. The inner and outer drill rods are divided into an inner tube hole and a double-walled interlayer channel, which replaces the traditional grouting pipeline and mud discharge pipeline, and realizes the sealed connection and torque transmission of the drill rod.
The equipment structure has been simplified, the operation difficulty has been reduced, the stability and torque transmission capacity of the drill pipe have been improved, it can adapt to complex terrain operations, and the risk of equipment failure has been reduced.
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Figure CN120946252A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of small-diameter pipe jacking machines, specifically relating to a large-diameter double-walled drill rod with a tongue-and-groove socket sealing connection structure. Background Technology
[0002] Traditional pipe jacking technology involves using a pipe jacking machine to excavate in front of the pipeline, while a hydraulic jacking device pushes it from the rear. Excavation can be done using water circulation within the pipeline, known as "slurry pipe jacking," or mechanical methods for direct soil removal, known as "soil pipe jacking." The pipe jacking machine consists of two sections, front and rear. A hydraulic cylinder forces the axes of the front and rear sections to form an angle, thus achieving steering correction.
[0003] This traditional pipe jacking technology is very popular in the field of large-diameter pipe jacking where people can enter the interior. It has no obvious defects or pain points and can cover various geological conditions. Therefore, for large-diameter pipe jacking, traditional pipe jacking technology and traditional pipe jacking machines are the absolute mainstream technology and equipment.
[0004] The equipment used in traditional pipe jacking technology is a traditional pipe jacking machine. It mainly consists of two parts: the pipe jacking machine (also called the pipe jacking machine head) and the hydraulic jacking device. Its core technology lies primarily in the pipe jacking machine.
[0005] The tunnel boring machine consists of two main parts: the cutterhead and the machine body. The machine body has three main internal mechanisms: (1) a rotating mechanism that drives the cutterhead to rotate; (2) a correction mechanism that drives the front chamber to turn with the cutterhead; and (3) a soil discharge mechanism. For slurry tunnel boring machines, this is the mud inlet and outlet pipe and the control valve; for soil tunnel boring machines, this is the mechanical soil discharge mechanism.
[0006] In trenchless pipeline construction technology, compared to the mature directional drilling and large-diameter pipe jacking technologies, small-diameter pipe jacking technology is still an immature field. This is because, currently, multiple technologies coexist in the field of small-diameter pipe jacking, and these technologies all have different serious shortcomings. No single technology can cover the vast majority of engineering situations and geological conditions for small-diameter pipe jacking and has yet to become the mainstream technology.
[0007] The internal structure of traditional pipe jacking machines is quite complex. This is not a problem for large-diameter pipe jacking machines, as personnel can enter and handle internal malfunctions. However, if a micro-pipe jacking machine still uses this internal structure, it becomes very difficult to troubleshoot if a malfunction occurs during construction, potentially leading to project failure. This poses a significant risk.
[0008] In the construction of urban stormwater and sewage pipe networks, small-diameter pipes account for a larger proportion. However, to date, there is no mature mainstream technology to rely on in this field, and no ideal pipe jacking machine is available. Most construction companies engaged in pipe jacking are afraid of the risks of small-diameter pipe jacking and directly abandon small-diameter pipe jacking business. Many projects that should have used pipe jacking have had to be changed to open excavation because they cannot find construction companies willing to undertake them.
[0009] To address the challenge of "inaccessibility for personnel" in micro-pipe jacking technology and machine design, our company has adopted an "external drive" approach as our innovation direction. This approach fundamentally avoids and improves upon the shortcomings of traditional micro-pipe jacking technology and machines, such as high risk, difficult operation, easy pipe blockage, and high overall construction cost. It completely solves the problem of the lack of ideal technology and equipment available in the current field of micro-pipe jacking.
[0010] One technical problem that needs to be solved in the external-drive micro-jacking technology is the setting of grouting pipelines and mud discharge pipelines. Existing pipe jacking machines require dedicated grouting pipelines and mud discharge pipelines. When continuing the drill rod during pipe jacking operations, the grouting pipeline and mud discharge pipeline need to be connected simultaneously. When constructing small-diameter pipelines, the traditional structure greatly increases the difficulty of the operation. Summary of the Invention
[0011] The purpose of this invention is to provide a large-diameter double-walled drill rod with a tongue-and-groove socket sealing connection structure, which is applied to the company's external-drive micro-jacking technology. The double-tube structure divides the internal space of the outer drill rod into two channels: an inner tube hole and a double-walled interlayer, replacing the grouting pipeline and mud discharge pipeline of the traditional pipe jacking machine, greatly simplifying the equipment structure.
[0012] The specific technical solution adopted by this invention is as follows:
[0013] A large-diameter double-walled drill rod with a tongue-and-groove socket sealing connection structure consists of an outer drill rod and an inner tube. The inner tube is held and fixed in the center of the inner hole of the outer drill rod by a support frame, dividing the internal space of the outer drill rod into two channels: the inner tube hole and the double-walled interlayer between the outer wall of the inner tube and the inner wall of the outer drill rod.
[0014] The front end of the external drill rod body is provided with a spigot connector sleeve, and the rear end is provided with a socket connector sleeve. The rear end of the socket connector sleeve is provided with several tongues and grooves, and the front end of the spigot connector sleeve is provided with several interlocking blocks that match the tongues and grooves.
[0015] The tongue and groove socket connection between external drill pipes involves inserting the outer sleeve of the socket joint into the outer sleeve of the socket joint of the adjacent drill pipe. When the socket is in place, the engagement block of the drill pipe engages with the tongue and groove of the adjacent drill pipe to achieve torque transmission and form an internal and external seal at the connection.
[0016] The inner tube adopts a reducing head socket connection method, the outer diameter of the front end of the inner tube body matches the inner diameter of the rear end of the tube body, and a sealing ring is fitted on the outer wall of the front end of the inner tube body.
[0017] Preferably, the outer sleeve of the socket joint is provided with a pair of rectangular locking rod holes, and the front end of the outer drill rod is provided with a bolt hole at the center of the rectangular locking rod hole position after insertion. When the drill rod is inserted into place, a locking rod stop is embedded in the rectangular locking rod hole, and the locking rod stop is fixed at the bolt hole by bolts.
[0018] Preferably, the number of tongue and groove joints and the number of interlocking blocks are each symmetrically arranged in two.
[0019] Preferably, the end of the external drill rod is provided with a sealing ring, which is embedded inside the outer sleeve of the socket joint.
[0020] Preferably, in order to enable the inner tube to have a reserved torque transmission function, the front end of the inner tube is provided with an outer octagonal sleeve with a spigot and the rear end is provided with an outer octagonal sleeve with a socket. The outer octagonal sleeve with a spigot can be inserted into the outer octagonal sleeve with a socket of the adjacent drill pipe.
[0021] Furthermore, the front end of the external drill rod is provided with a groove corresponding to the rectangular locking hole.
[0022] The technical effects achieved by this invention are as follows:
[0023] This invention provides a large-diameter double-walled drill rod with a tongue-and-groove socket sealing connection structure, consisting of an outer drill rod and an inner tube. The outer drill rod serves as the drive rod, and the inner tube is held and fixed at the center of the inner hole of the outer drill rod by a support frame. The internal space of the outer drill rod is divided into two channels: the inner tube hole and the double-walled interlayer between the outer wall of the inner tube and the inner wall of the outer drill rod. The large-diameter double-walled drill rod is connected by sealing the outer drill rod with the outer drill rod and sealing the inner tube with the inner tube. This makes the inner tube hole and the double-walled interlayer of the drill rod two independent continuous channels after the connection. The inner tube hole serves as the mud discharge channel, and the double-walled interlayer serves as the grouting channel. There is no need to set up separate grouting pipelines and mud discharge pipelines, which greatly simplifies the equipment structure and the operation process, and provides a suitable drill rod technology for the realization of externally driven micro-jacking pipe technology.
[0024] The external drill pipe of this invention adopts a tongue and groove socket sealing connection structure. When the socket is in place, the biting block of the drill pipe and the tongue and groove of the adjacent drill pipe bite each other to realize torque transmission and form an internal and external seal at the connection. The rectangular locking hole and locking block are set to ensure the stability of the drill pipe connection. At the same time, the matching setting of the locking block and the slot ensures that the drill pipe can withstand greater jacking force and pullback force, thus adapting to more complex terrain operations.
[0025] The inner tube of the present invention has a reserved torque transmission function by setting an octagonal sleeve for the spigot and an octagonal sleeve for the socket. When encountering a higher torque operation requirement, the torque can be transmitted through the inner tube. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of a large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to the present invention;
[0027] Figure 2 This is an axial sectional view of a large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to the present invention;
[0028] Figure 3 This is a schematic diagram of the inner tube structure of the present invention;
[0029] Figure 4 This is a schematic diagram of a large-diameter double-wall drill pipe socket connection using a tongue-and-groove sealing connection structure according to the present invention.
[0030] The attached diagram lists the components represented by each number as follows:
[0031] 1. External drill rod; 2. Inner tube; 3. Support frame; 4. Inner tube hole; 5. Double-walled sandwich; 6. Spigot joint outer sleeve; 7. Socket joint outer sleeve; 8. Tongue and groove; 9. Engaging block; 10. Rectangular locking rod hole; 11. Bolt hole; 12. First sealing ring; 13. Slot; 14. Second sealing ring; 15. Spigot outer octagonal sleeve; 16. Socket outer octagonal sleeve; 17. Locking rod stop block; 18. Bolt. Detailed Implementation
[0032] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention.
[0033] Example 1:
[0034] This embodiment provides a large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure, as shown in the following figure. Figure 1-3 As shown, it consists of an outer drill rod 1 and an inner tube 2. The inner tube 2 is held and fixed in the center of the inner hole of the outer drill rod 1 by a support frame 3, dividing the internal space of the outer drill rod 1 into two channels: an inner tube hole 4 and a double-walled interlayer 5 between the outer wall of the inner tube and the inner wall of the outer drill rod.
[0035] The front end of the external drill rod 1 is provided with a spigot connector sleeve 6, and the rear end is provided with a socket connector sleeve 7. The rear end of the socket connector sleeve 7 is provided with two tongue and groove joints 8, and the front end of the spigot connector sleeve 6 is provided with two interlocking blocks 9 that match the tongue and groove joints 8.
[0036] The outer sleeve 7 of the socket joint is provided with a pair of rectangular locking rod holes 10 on its side wall, and a bolt hole 11 is provided on the front end of the outer drill rod 1 at the center of the rectangular locking rod hole 10 after insertion.
[0037] The outer drill rod 1 has a first sealing ring 12 at its end, which is embedded inside the outer sleeve 7 of the socket joint.
[0038] The front end of the external drill rod 1 is provided with a slot 13 corresponding to the rectangular locking hole 10.
[0039] The inner tube 2 adopts a large and small end socket connection method. The outer diameter of the front end of the inner tube 2 matches the inner diameter of the rear end of the tube. A second sealing ring 14 is sleeved on the outer wall of the front end of the inner tube 2.
[0040] To enable the inner tube to have a reserved torque transmission function, the front end of the inner tube 2 is provided with a spigot outer octagonal sleeve 15 and the rear end is provided with a socket outer octagonal sleeve 16. The spigot outer octagonal sleeve 15 can be inserted into the socket outer octagonal sleeve 16 of the adjacent drill pipe.
[0041] like Figure 4 As shown, the tongue and groove connection between the outer drill pipes 1 is achieved by inserting the outer sleeve 6 of the spigot connector into the outer sleeve 7 of the socket connector of the adjacent drill pipe. When the spigot is in place, the engagement block 9 of the outer drill pipe and the tongue and groove 8 of the adjacent outer drill pipe engage with each other to achieve torque transmission and form an internal and external seal at the connection. The front end of the inner tube is inserted into the rear end of the connected inner tube, and the outer octagonal sleeve 15 of the spigot is inserted into the outer octagonal sleeve 16 of the socket of the adjacent inner tube to achieve a sealed continuation of the inner tube. The locking rod stop 17 is embedded in the rectangular locking rod hole 10 and snapped into the slot 13. The locking rod stop 17 is fixed in the bolt hole 11 by the bolt 18 to achieve a stable connection of the drill pipes.
[0042] This embodiment provides a large-diameter double-walled drill rod with a tongue-and-groove socket sealing connection structure, consisting of an outer drill rod 1 and an inner tube 2. The outer drill rod 1 is the driving rod, and the inner tube 2 is held and fixed in the center of the inner hole of the outer drill rod 1 by a support frame 3. The internal space of the outer drill rod 1 is divided into two channels: an inner tube hole 4 and a double-walled interlayer 5 between the outer wall of the inner tube and the inner wall of the outer drill rod. The connection of the large-diameter double-walled drill rod is a sealed connection between the outer drill rods and between the inner tubes, so that the inner tube hole 4 and the double-walled interlayer 5 of the drill rod become two independent continuous channels after the connection. The inner tube hole 4 serves as the mud discharge channel, and the double-walled interlayer 5 serves as the grouting channel. There is no need to set up separate grouting pipelines and mud discharge pipelines, which greatly simplifies the equipment structure and the operation process, and provides a suitable drill rod technology for the realization of the external drive micro-jacking technology.
[0043] In this embodiment, the outer drill rod 1 adopts a tongue and groove socket sealing connection structure. When the socket is in place, the engagement block 9 of the outer drill rod and the tongue and groove 8 of the adjacent drill rod engage with each other to achieve torque transmission and form an internal and external seal at the connection. The rectangular locking rod hole 10 and the locking rod stop 17 ensure the stability of the drill pipe connection. At the same time, the matching of the locking rod stop 17 and the slot 13 ensures that the drill rod can withstand greater jacking force and pullback force, thus adapting to more complex terrain operations.
[0044] In this embodiment, the inner tube 2 is provided with an outer octagonal sleeve 15 for the spigot and an outer octagonal sleeve 16 for the socket, so that the inner tube 2 has a reserved torque transmission function. When encountering a higher torque operation requirement, the torque can be transmitted through the inner tube.
[0045] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention are implemented according to conventional methods in the art unless otherwise specified or limited.
Claims
1. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure, comprising an outer drill pipe and an inner tube, characterized in that: The inner tube is held and fixed at the center of the inner hole of the outer drill rod by a support frame, dividing the internal space of the outer drill rod into two channels: the inner tube hole and the double-walled interlayer between the outer wall of the inner tube and the inner wall of the outer drill rod. The front end of the outer drill rod body is provided with a spigot connector sleeve, and the rear end is provided with a socket connector sleeve. The rear end of the socket connector sleeve is provided with several tongues and grooves, and the front end of the spigot connector sleeve is provided with several interlocking blocks that match the tongues and grooves. The outer diameter of the front end of the inner tube body matches the inner diameter of the rear end of the tube body.
2. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to claim 1, characterized in that: A sealing ring is fitted on the outer wall of the front end of the inner tube.
3. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to claim 1, characterized in that: The outer sleeve of the socket joint is provided with a pair of rectangular locking rod holes. The front end of the outer drill rod is provided with a bolt hole at the center of the rectangular locking rod hole after insertion. When the drill rod is inserted into place, a locking rod stop is embedded in the rectangular locking rod hole, and the locking rod stop is fixed at the bolt hole by bolts.
4. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to claim 1, characterized in that: The number of tongue and groove joints and the number of interlocking blocks are each symmetrically arranged in two.
5. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to claim 1, characterized in that: The end of the external drill rod is provided with a sealing ring, which is embedded inside the outer sleeve of the socket joint.
6. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to claim 1, characterized in that: The inner tube has an octagonal sleeve at the front end and an octagonal sleeve at the rear end, and the octagonal sleeve at the front end can be inserted into the octagonal sleeve at the rear end of the adjacent drill pipe.
7. A large-diameter double-walled drill pipe with a tongue-and-groove socket sealing connection structure according to claim 3, characterized in that: The front end of the external drill rod is provided with a slot corresponding to the rectangular locking hole.