Core rod jacking type mechanical reaming device

Abstract

The utility model belongs to the technical field of coal seam pressure relief and permeability increase, and relates to a core rod jacking type mechanical reaming device which comprises a core rod jacking type reamer, a core rod drill rod, a combined type rotary water tail and a hydraulic propeller which are sequentially connected from head to tail. The core rod jacking type reamer adopts a core rod pushing linkage structure, and the opening or closing state of a tool arm is accurately controlled; the core rod drill rod provides core rod guiding conduction, and deep hole reaming is achieved. The composite rotary water tail is used for rotary dynamic sealing connection of the drill rod core rod and the hydraulic propeller; the hydraulic propeller is used for being connected with hydraulic power and providing hydraulic propelling power for the guide rod. According to the device, hydraulic pressure serves as power to achieve rapid unfolding and retracting of the reaming cutter, the reaming speed is increased, the gas extraction drilling and reaming requirements are met, and stable operation can be achieved under the complex geological condition.

Description

Technical Field

[0001] This utility model belongs to the field of coal seam depressurization and permeability enhancement technology, and relates to a core rod jacking mechanical hole expansion device. Background Technology

[0002] my country possesses abundant coal reserves, which occupy a vital position in its energy structure and are a key pillar for ensuring national energy security. However, with the continuous increase in coal mining depth, the gas content and pressure in coal seams are constantly rising, significantly increasing the risk of gas accidents and posing a severe challenge to safe coal mine production. Gas drainage is a crucial step in ensuring safe production during coal mining. However, most coal seams in my country have poor permeability, classified as low-permeability coal seams, resulting in low gas drainage efficiency and failing to meet the dual requirements of safe production and efficient drainage. Therefore, improving gas drainage efficiency has become a critical issue that urgently needs to be addressed in current coal mining operations.

[0003] Coal seam permeability enhancement technology, as a core means to improve gas drainage efficiency, has received widespread attention. However, the confined working environment in coal mines places extremely stringent requirements on permeability enhancement equipment, which must possess characteristics such as high strength, small size, and ease of operation. Currently, traditional coal seam permeability enhancement technologies have many drawbacks. Traditional hydraulic or blasting enlargement technologies present significant safety risks during implementation, while the latter faces difficulties in implementation. High-pressure water jet cutting of coal can achieve coal cutting to a certain extent, but the equipment structure is complex, consumes a large amount of water, and the borehole wall is prone to collapse during the cutting process, affecting subsequent gas drainage operations. Blasting enlargement technology not only poses significant safety hazards, but also makes it difficult to precisely control the shape and size of the enlarged borehole, failing to meet the requirements of efficient gas drainage. When conventional drilling tools are used with ordinary drill bits, only cylindrical holes can be formed, failing to achieve "cavity" enlargement, resulting in limited permeability enhancement effects in the coal seam. Traditional mechanical hole enlargement methods mostly rely on the thrust of the drilling rig to achieve drill bit diameter change, resulting in slow hole enlargement speed and long working cycle, making it difficult to meet the actual needs of efficient gas extraction.

[0004] In summary, existing coal seam permeability enhancement technologies have shortcomings in terms of safety, perforation effect, and efficiency, failing to meet the needs of safe coal mine production and efficient gas extraction. Therefore, there is an urgent need to develop a new type of coal seam perforation enhancement device to effectively improve the pressure relief and permeability enhancement effect of coal seams, providing a strong guarantee for safe production and efficient mining in coal mines. Utility Model Content

[0005] In view of this, the purpose of this utility model is to provide a core rod jacking mechanical hole enlarging device, which controls the opening speed of the hole enlarging cutter arm through the internal core rod of the device to realize the hole enlarging of the coal seam, so as to solve the problems of difficulty in opening and retrieving the hole enlarging cutter arm and slow hole enlarging speed.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A core rod jacking mechanical reaming device includes a core rod jacking reamer, a core rod drill rod, a composite rotating tailpipe, and a hydraulic propulsion unit connected sequentially from head to tail.

[0008] The core rod jacking type reamer includes a reamer core rod, a cutter arm, and a reamer body. The reamer core rod is axially movably arranged in the inner cavity of the reamer body. There are at least two cutter arms arranged on the outside of the reamer core rod. One end of each cutter arm is hinged to the reamer body. At the end of the cutter arm that is hinged to the reamer body, a cutter arm gear is provided that meshes with the core rod gear on the reamer core rod. The opening and closing of the cutter arms are controlled by the axial pushing and pulling action of the reamer core rod.

[0009] The core drill rod includes a drill rod body and a drill rod core rod. The two ends of the drill rod body are respectively connected to the reamer body and the composite rotating tail. The drill rod core rod is axially movably arranged in the inner cavity of the drill rod body and connected to the reamer core rod to axially push the reamer core rod.

[0010] The hydraulic thruster is installed at the tail end of the composite rotating tailstock and has a guide rod for driving the drill core rod to move axially.

[0011] The core rod jacking type reamer adopts a core rod propulsion linkage structure to precisely control the opening or closing state of the cutter arm; the core rod drill rod provides core rod guidance and conduction to realize deep hole reaming; the composite rotary water tail is used for the rotary dynamic seal connection of the drill rod core rod and hydraulic propeller; the hydraulic propeller is used to connect hydraulic power and provide hydraulic propulsion power for the guide rod.

[0012] Furthermore, the core rod jacking type reamer also includes female connector caps and male connectors installed at both ends of the reamer body, for connecting the drill rod body and the drill bit respectively. The connection between the female connector caps and male connectors can be selected to be threaded or diamond-shaped plug-in type to adapt to different core rod drill rods and drill bits.

[0013] Furthermore, the female connector cap is connected to the reamer core rod via a stop connection to restrict the axial displacement of the reamer core rod toward the core rod drill rod direction;

[0014] A compression spring is fitted at one end of the reamer core rod near the male connector, and the two ends of the compression spring are respectively connected to the protrusion on the outside of the reamer core rod and the male connector to provide elastic force to the reamer core rod in the direction of the female connector cap.

[0015] Furthermore, the body of the reamer has a groove inside for mounting the reamer core rod and a reserved axial advance space, and grooves on both sides of the middle part for mounting the cutter arm.

[0016] Furthermore, the outer wall of the drill rod body adopts a shallow thread design, and the inner cavity is provided with a groove for installing the drill rod core rod and a reserved axial advance space.

[0017] Furthermore, the outer side of the drill rod core is provided with a limiting protrusion, and a corresponding stop is provided in the groove of the drill rod body to axially limit the drill rod core.

[0018] Furthermore, the composite rotary tail includes an inlet, a rotary sealing body, and a tail connector. The inlet and the tail connector are respectively arranged at both ends of the rotary sealing body. The inlet is used to connect a water pipe or an air supply pipe for drilling slag removal. The rotary sealing body is used for the rotary dynamic sealing connection between the drill rod core rod and the hydraulic thruster and the inlet. The tail connector is used for matching connection with the core rod drill rod.

[0019] Furthermore, the water tail connector and the core drill rod are connected by a threaded or plug-in connection.

[0020] Furthermore, the hydraulic thruster also includes a hydraulic valve body and a hydraulic guide mechanism. The hydraulic valve body is installed at the tail end of the composite rotating water jet and is used to connect to the hydraulic pipeline. The hydraulic guide mechanism is arranged in the hydraulic valve body to provide hydraulic propulsion power for the guide rod.

[0021] The guide rod axially penetrates the composite rotating tailstock and connects to the drill rod core rod to drive the drill rod core rod to move axially.

[0022] The beneficial effects of this utility model are as follows:

[0023] 1. This utility model proposes a mandrel-driven mechanical reaming device, the core of which lies in the innovative combination of a mandrel-driven reamer, a mandrel drill rod, a composite rotating water jet, and a hydraulic propulsion unit. These components are hydraulically powered, enabling rapid deployment and retraction of the reaming arm, significantly improving reaming speed and efficiency. Compared to traditional reaming equipment, this device can not only flexibly adapt to the reaming requirements of different diameters but also maintain stable operation under complex geological conditions. This design reduces equipment failure rates, ensures construction safety, and provides reliable technical support for operations in industries such as coal mining.

[0024] 2. Utilizing the cutter arm borehole enlargement technology, this device can efficiently cut and remove large amounts of coal, forming larger-diameter chambers and fracture networks. This not only increases the exposed area of ​​the coal seam but also significantly improves its permeability, creating more favorable conditions for gas migration and extraction. In practical applications, this borehole enlargement method greatly improves the efficiency and output of gas extraction, effectively reducing the safety hazards caused by gas accumulation. Compared to traditional methods, it creates a wider fracture network and achieves better extraction results, providing crucial protection for safe coal mine production.

[0025] 3. The device features a simple structure, easy operation, and precise control, enabling integrated drilling and reaming operations. Operators can operate it without complex training, reducing usage and maintenance costs. Its modular design and high integration further enhance its field adaptability.

[0026] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0027] To make the objectives, technical solutions, and advantages of this utility model clearer, the preferred embodiments of this utility model will be described in detail below with reference to the accompanying drawings, wherein:

[0028] Figure 1 This is a schematic diagram of the overall structure of a core rod jacking mechanical hole-expanding device in an embodiment;

[0029] Figure 2 This is a schematic diagram of the core rod jacking type expander in the embodiment;

[0030] Figure 3 This is a schematic diagram of the core drill rod structure in the embodiment;

[0031] Figure 4 This is a schematic diagram of the composite rotating tail structure in the embodiment;

[0032] Figure 5 This is a schematic diagram of the hydraulic thruster in the embodiment.

[0033] Reference numerals: 1-Mandrel jacking reamer, 2-Mandrel drill rod, 3-Composite rotating tailpipe, 4-Hydraulic thruster;

[0034] Core rod jacking type reamer: 1-1-Female connector cover, 1-2-Reamer core rod, 1-3-Cutter arm, 1-4-Reamer body, 1-5-Male connector, 1-6-Compression spring;

[0035] Core drill rod: 2-1-Drill rod body, 2-2-Drill rod core rod;

[0036] Composite rotating tailpipe: 3-1-Inlet, 3-2-Rotating seal, 3-3-Tailpipe connector;

[0037] Hydraulic thruster: 4-1-Hydraulic valve body, 4-2-Hydraulic guide mechanism, 4-3-Guide rod. Detailed Implementation

[0038] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this utility model. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0039] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the present invention. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0040] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this utility model. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0041] Example 1

[0042] This embodiment provides a core rod jacking type mechanical borehole enlargement device and its usage method, used to solve the problem of borehole enlargement in coal seam gas extraction. The device is attached... Figure 1 As shown, it includes a core rod jacking reamer 1, a core rod drill rod 2, a composite rotating tailpipe 3, and a hydraulic propulsion unit 4, which are connected in sequence from head to tail.

[0043] The core rod jacking type reamer 1 includes a female connector cap 1-1, a male connector 1-5, a reamer core rod 1-2, a cutter arm 1-3, and a reamer body 1-4.

[0044] The body of the reamer 1-4 has a groove for mounting the reamer core rod 1-2 and a reserved space for axial advancement; the two sides of the middle part have grooves for mounting the cutter arm 1-3.

[0045] The reamer core rod 1-2 can move axially and is installed in the groove inside the reamer body 1-4.

[0046] Two cutter arms 1-3 are provided, located outside the reamer core rod 1-2, and arranged symmetrically. One end of each cutter arm is connected to the reamer body 1-4 via a hinge, and a cutter arm gear is provided at the hinge, which meshes with the core rod gear on the reamer core rod 1-2. The opening and closing of the cutter arms 1-3 can be controlled by pushing and pulling the reamer core rod 1-2.

[0047] The female connector cap 1-1 and the male connector 1-5 are respectively installed at both ends of the reamer body 1-4 to connect the drill rod body 2-1 and the drill bit. The connection is a threaded connection design.

[0048] The core drill rod 2 includes the drill rod body 2-1 and the drill rod core rod 2-2.

[0049] The drill rod body 2-1 is connected to the reamer body 1-4 and the composite rotating tail 3 at both ends.

[0050] The drill rod core rod 2-2 is axially movable in the inner cavity of the drill rod body 2-1 and is connected to the reamer core rod 1-2 to push the reamer core rod 1-2 to move.

[0051] The composite rotating tail 3 includes an inlet 3-1, a rotating sealing body 3-2, and a tail connector 3-3.

[0052] Connect the water pipe to inlet 3-1 for drilling and slag removal.

[0053] The rotary seal 3-2 ensures a rotary dynamic seal between the drill rod core 2-2 and the hydraulic thruster 4 and the inlet 3-1.

[0054] The tail connector 3-3 and the core drill rod 2 are connected by a thread.

[0055] The hydraulic thruster 4 includes a hydraulic valve body 4-1, a hydraulic guiding mechanism 4-2, and a guide rod 4-3.

[0056] The hydraulic valve body 4-1 is installed at the tail end of the composite rotating tail 3 and connected to the hydraulic pipeline.

[0057] The hydraulic guiding mechanism 4-2 provides hydraulic propulsion power for the guide rod 4-3.

[0058] The guide rod 4-3 axially penetrates the composite rotating tailstock 3 and connects with the drill rod core rod 2-2, driving its axial movement.

[0059] It should be noted that the key to this embodiment lies in the structural combination of the core rod jacking reamer 1, the core rod drill rod 2, the composite rotating tail 3 and the hydraulic propulsion 4, and the specific structure of the core rod jacking reamer 1. The core rod drill rod 2, the composite rotating tail 3 and the hydraulic propulsion 4 can also be replaced by other conventional structures in the prior art. Therefore, the above only briefly describes their functional structure and will not go into too much detail.

[0060] The method of using this core rod jacking type mechanical reaming device is as follows:

[0061] Install the core drill rod 2 onto the drilling rig, connect the core drill rod jacking reamer 1 and the drill bit in sequence, adjust the opening height, inclination angle and azimuth angle, and carry out drilling operations.

[0062] After drilling reaches the designed depth, install the tailpipe connector 3-3 and the hydraulic thruster 4, connect the hydraulic pipeline, and control the opening and closing of the cutter arm 1-3.

[0063] The borehole is enlarged from the bottom towards the opening, with the hydraulic pressure controlled between 2 and 4 MPa. For cross-strata boreholes, the enlargement section is 1m long with 4m intervals, stopping at 15m from the opening. The coal output of the enlarged section is recorded, and the enlargement tool is removed and properly stored after completion.

[0064] Furthermore, the composite rotating tail 3 can also be connected to the core drill rod 2 during drilling operations to assist in slag removal.

[0065] Example 2

[0066] This embodiment further optimizes the device structure based on specific embodiment 1 to improve operational efficiency and stability.

[0067] Improvement of the core rod jacking type reamer 1

[0068] The female connector cap 1-1 and the reamer core rod 1-2 are connected by a stop joint to limit the excessive displacement of the reamer core rod 1-2 towards the core rod drill rod 2.

[0069] A compression spring 1-6 is fitted onto one end of the reamer core rod 1-2 near the male connector 1-5. Its two ends are respectively connected to the outer protrusion of the reamer core rod 1-2 and the male connector 1-5, providing elastic force in the direction of the female connector cover 1-1 to accelerate the closing of the cutter arm 1-3.

[0070] Improvements to core drill rod 2

[0071] The outer wall of the drill rod body 2-1 adopts a shallow thread design to enhance the friction with the inner wall of the borehole; the inner cavity is provided with a groove for the installation of the drill rod core rod 2-2, and axial advance space is reserved.

[0072] The drill rod core 2-2 has a limiting protrusion on its outer side, and the drill rod body 2-1 has a corresponding stop in its groove to achieve axial limiting.

[0073] Specifically, the drill rod core 2-2 is installed into the drill rod body 2-1 through one end of the drill rod body 2-1. After installation, the male connector of the drill rod body is welded to the drill rod body 2-1, and then the drill rod core 2-2, which forms a stop connection with the drill rod body 2-1, is installed into the drill rod body 2-1.

[0074] Specifically, in this embodiment, the outer diameter of the core rod jacking type reamer 1 is Φ96mm, the length is 650mm, the length of the cutter arm is 200mm, and the length of the groove for installing the cutter arm is 210mm.

[0075] The drill rod body 2-1 has an outer diameter of Φ76mm and a length of 1000mm, and the drill rod core rod 2-2 has an outer diameter of Φ30mm and a length of 1000mm.

[0076] The inlet 3-1 of the composite rotating water jet has a size of Φ25mm. In the hydraulic thruster, the hydraulic pipeline has a size of Φ10mm, the oil pressure is 2-4MPa, and the guide rod stroke is 100mm.

[0077] The method of using this core rod jacking type mechanical reaming device is as follows:

[0078] As in Example 1, complete the drilling operation and install the relevant components.

[0079] Control of the opening and closing of blade arms 1-3:

[0080] Opening: The guide rod 4-3 of the hydraulic thruster 4 moves toward the bottom of the hole under hydraulic drive, pushing the drill rod core rod 2-2 and the reamer core rod 1-2 to move. The cutter arm 1-3 opens through gear meshing and is maintained in the open state by hydraulic pressure.

[0081] Closure: When the hydraulic drive stops, the cutter arm 1-3 is automatically closed by the pressure of the inner wall of the borehole. The compression spring 1-6 helps the reamer core rod 1-2 to reset, driving the drill core rod 2-2 and guide rod 4-3 back to their original positions.

[0082] Specifically, Example 2 involves a cross-seam borehole reaming operation with a coal seam thickness of 6m, a borehole depth of 40m, and an inclination angle of 80°. The entire coal seam section of the cross-seam borehole is reamed to a depth of 6m. The coal output of the reamed section is recorded. After reaming is completed, the reaming drill bit is removed and properly stored, and the borehole is sealed for continuous pumping.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model 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 solution of this utility model without departing from the spirit and scope of this technical solution, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A core rod jacking type mechanical reaming device, characterized in that: It includes a mandrel jacking reamer, a mandrel drill rod, a composite rotating tailpipe, and a hydraulic propulsion unit, which are connected sequentially from beginning to end; The core rod jacking type reamer includes a reamer core rod, a cutter arm, and a reamer body. The reamer core rod is axially movably arranged in the inner cavity of the reamer body. There are at least two cutter arms arranged on the outside of the reamer core rod. One end of each cutter arm is hinged to the reamer body. At the end of the cutter arm that is hinged to the reamer body, a cutter arm gear is provided that meshes with the core rod gear on the reamer core rod. The opening and closing of the cutter arms are controlled by the axial pushing and pulling action of the reamer core rod. The core drill rod includes a drill rod body and a drill rod core rod. The two ends of the drill rod body are respectively connected to the reamer body and the composite rotating tail. The drill rod core rod is axially movably arranged in the inner cavity of the drill rod body and connected to the reamer core rod to axially push the reamer core rod. The hydraulic thruster is installed at the tail end of the composite rotating tailstock and has a guide rod for driving the drill core rod to move axially.

2. The apparatus according to claim 1, characterized in that: The core rod jacking type reamer also includes female connector caps and male connectors installed at both ends of the reamer body, for connecting the drill rod body and the drill bit respectively. The connection between the female connector caps and male connectors can be selected to be threaded or diamond-shaped plug-in type to adapt to different core rod drill rods and drill bits.

3. The apparatus according to claim 2, characterized in that: The female connector cap is connected to the reamer core rod via a stop to restrict the axial displacement of the reamer core rod toward the core rod drill rod direction; A compression spring is fitted at one end of the reamer core rod near the male connector, and the two ends of the compression spring are respectively connected to the protrusion on the outside of the reamer core rod and the male connector to provide elastic force to the reamer core rod in the direction of the female connector cap.

4. The apparatus according to claim 1, characterized in that: The reamer body has a groove inside for mounting the reamer core rod and a reserved axial advance space, and grooves on both sides of the middle part for mounting the cutter arm.

5. The apparatus according to claim 1, characterized in that: The outer wall of the drill rod body is designed with shallow threads, and the inner cavity is provided with a groove for installing the drill rod core rod and reserved axial advance space.

6. The apparatus according to claim 5, characterized in that: The drill rod core is provided with a limiting protrusion on its outer side and a corresponding stop is provided in the groove of the drill rod body to limit the drill rod core axially.

7. The apparatus according to claim 1, characterized in that: The composite rotary tail includes an inlet, a rotary sealing body, and a tail connector. The inlet and the tail connector are respectively arranged at both ends of the rotary sealing body. The inlet is used to connect a water pipe or an air supply pipe for drilling slag removal. The rotary sealing body is used for the rotary dynamic sealing connection between the drill rod core and the hydraulic thruster and the inlet. The tail connector is used for matching connection with the core drill rod.

8. The apparatus according to claim 7, characterized in that: The tailpipe connector and the core drill rod are connected by a threaded or plug-in method.

9. The apparatus according to claim 1, characterized in that: The hydraulic thruster also includes a hydraulic valve body and a hydraulic guide mechanism. The hydraulic valve body is installed at the tail end of the composite rotating water tail and is used to connect to the hydraulic pipeline. The hydraulic guide mechanism is arranged in the hydraulic valve body to provide hydraulic propulsion power for the guide rod. The guide rod axially penetrates the composite rotating tailstock and connects to the drill rod core rod to drive the drill rod core rod to move axially.

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