Reaming guide device for core drilling
The core drilling reaming guide device with a self-locking structure design solves the problems of easy breakage and difficult disassembly of the guide rod, realizes the stable connection and quick unlocking of the guide drill bit, and improves the accuracy of reaming operations and the integrity of core samples.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- QINGHAI PROVINCIAL SECOND GEOLOGICAL EXPLORATION INSTITUTE
- Filing Date
- 2025-07-12
- Publication Date
- 2026-05-19
AI Technical Summary
In existing technologies, borehole reaming guide devices are prone to breakage due to shear forces during drilling, leading to the detachment of the guide rod. Furthermore, the guide device is difficult to disassemble quickly after borehole reaming, affecting construction efficiency and the integrity of core samples.
A core drilling reaming guide device was designed, which adopts a self-locking structure, including a core expansion and a sleeve. Through the interaction of a thrust spring and a tension spring, a reliable connection and convenient separation between the guide part and the core tube are achieved, ensuring the coaxiality of the guide drill bit and the core drill bit, and quick unlocking is achieved through rope operation.
This improved the efficiency of installing and dismantling the guiding device, ensured the accuracy of the borehole enlargement operation and the integrity of the core sample, and increased the success rate of drilling and construction efficiency.
Smart Images
Figure CN224260294U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of geological exploration equipment technology, specifically a core drilling borehole enlargement guide device. Background Technology
[0002] In geological core drilling, mud wall protection technology often fails when encountering complex strata such as borehole leakage, borehole wall collapse, and karst caves and fissures, making it impossible to continue drilling. In such cases, it is necessary to first enlarge the borehole and run casing to stabilize the borehole wall before drilling can continue normally.
[0003] A common method for guiding borehole reaming is to first insert a guide rod, one diameter smaller than the core tube, into the core tube, and then use a pin to fix the guide rod to the core tube. However, due to severe drill bit vibration during reaming, the pin is prone to breakage under shear force, leading to the guide rod falling off and causing complex accidents inside the borehole.
[0004] In addition, after the borehole enlargement operation is completed, in order to ensure that the drilled core can be successfully inserted into the core tube, the entire drilling structure needs to be removed from the underground hole, and the guide rod needs to be removed before drilling can be restarted and restarted. This not only takes a long time, but also greatly reduces the construction efficiency.
[0005] Therefore, a core drilling borehole enlargement guidance device is proposed to address the current shortcomings. Utility Model Content
[0006] To address the problems of the prior art, this utility model provides a core drilling reaming guide device.
[0007] The technical problem to be solved by this utility model is to overcome the defects of the above-mentioned technology and provide a core drilling reaming guide device.
[0008] To solve the above-mentioned technical problems, the technical solution provided by this utility model is a core drilling reaming guide device, comprising:
[0009] Core tube, the bottom end of which is connected to a coring drill bit;
[0010] The guide part includes an inner tube and a guide rod. The inner tube is disposed inside the core tube and connected by a self-locking part. One end of the guide rod is connected to the inner tube, and the other end is connected to the guide drill bit located outside the core drill bit.
[0011] The self-locking part includes an expansion core and expansion sleeves. The inner tube is provided with a plurality of expansion sleeves that can move radially along the inner tube. The expansion core is slidably disposed in the inner tube and cooperates with the expansion sleeves. The core tube is provided with a groove that cooperates with the expansion sleeves. The bottom end of the expansion core is provided with a tension spring connected to the inner tube. The inner tube is provided with a limiting ring above the expansion core. The upper end of the expansion core is provided with a thrust spring connected to the limiting ring. The expansion core is provided with a spearhead connected to a rope.
[0012] As an improvement, the axial engagement length of the expansion core and the expansion sleeve in the driving engagement state is denoted as L1, the distance between the limiting ring and the upper abutment surface of the expansion core is denoted as L2, and the radial engagement length of the expansion sleeve and the slot in the snap-fit engagement state is denoted as L3; wherein, L1>L2>L3.
[0013] As an improvement, the expansion core is located on the upper side of the expansion sleeve. The expansion core includes a sliding part and a working part. The sliding part slides in cooperation with the inner wall of the inner tube, and the working part has a tapered structure that tapers downward and cooperates with the inner side of the expansion sleeve.
[0014] As an improvement, the upper and / or lower ends of the plurality of expansion sleeves are provided with retaining rings.
[0015] As an improvement, the slot includes an annular limiting groove formed on the inner wall of the core tube and adapted to the expansion sleeve, and the inner side wall of the annular limiting groove is provided with a locking groove that matches the shape of the outer end of the expansion sleeve.
[0016] As an improvement, the inner tube is provided with a connecting plate below the expansion sleeve, and the two ends of the tension spring are respectively fixedly connected to the expansion core and the connecting plate.
[0017] The advantages of this utility model compared with the prior art are as follows:
[0018] 1. This device, through its self-locking structure design, achieves reliable connection and convenient separation between the guide section and the core tube. The expansion core and expansion sleeve in the self-locking section, utilizing the interaction of a thrust spring and a tension spring, not only ensure that the expansion sleeve can stably expand outward and securely lock with the groove on the core tube under normal conditions, but also that during unlocking, a simple rope pulling operation allows for rapid contraction and disengagement of the expansion sleeve, greatly improving the efficiency of guide section installation and disassembly during drilling operations.
[0019] 2. During the reaming stage, the guide unit is securely locked onto the core tube, effectively ensuring the coaxiality of the guide drill bit and the coring drill bit. This allows the guide drill bit to precisely revolve around the coring drill bit during rotation. This helps improve the quality and stability of the reaming operation, avoiding problems such as core sample damage or drilling trajectory deviation caused by reaming position misalignment. This enhances the overall accuracy and success rate of core drilling, providing strong support for the complete extraction of subsequent core samples.
[0020] 3. This device effectively protects the integrity of the core sample. After the borehole enlargement operation is completed, the guide section is smoothly removed via rope, avoiding the guide section's occupation of the space inside the core tube. This allows the coring drill bit to fully fill the core sample and extract it intact to the surface, improving the core sample recovery rate and quality, which is of great significance for geological exploration and research. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the structure of a core drilling borehole enlargement guiding device according to this utility model.
[0022] Figure 2 This is a schematic diagram of the internal structure of a core drilling borehole enlargement guiding device according to this utility model.
[0023] Figure 3 yes Figure 2 A magnified view of a portion of point A in the middle.
[0024] Figure 4 This is a front view of a core drilling borehole enlargement guide device according to this utility model.
[0025] Figure 5 yes Figure 4 Sectional view at point BB.
[0026] Figure 6 yes Figure 5 A magnified view of a section at point D.
[0027] Figure 7 yes Figure 4 Sectional view at point CC.
[0028] Figure 8 This is a schematic diagram of the self-locking part in a core drilling reaming guide device of this utility model.
[0029] As shown in the figure:
[0030] 1. Core tube; 11. Slot section; 111. Annular limiting groove; 112. Locking groove;
[0031] 2. Core drill bit;
[0032] 3. Guide section; 31. Inner tube; 32. Guide rod; 33. Guide drill bit; 34. Limiting ring; 35. Connecting plate;
[0033] 4. Self-locking part; 41. Expansion core; 411. Sliding part; 412. Working part; 42. Expansion sleeve; 43. Tension spring; 44. Thrust spring; 45. Spearhead; 46. Snap ring. Detailed Implementation
[0034] To make the objectives, technical solutions, and advantages of the utility model embodiments clearer, the technical solutions of the utility model embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the utility model, not all embodiments. The components of the utility model embodiments described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.
[0035] In the description of the embodiments of the utility model, it should be noted that if terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," or "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, they are only for the convenience of describing the 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, and therefore should not be construed as a limitation on the utility model. Furthermore, terms such as "first," "second," and "third" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0036] Furthermore, the use of terms such as "horizontal," "vertical," and "sag" does not imply that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0037] In the description of the utility model embodiments, "a plurality of" means at least two.
[0038] In the description of the embodiments of the utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the utility model according to the specific circumstances.
[0039] As shown in the attached figures, a core drilling reaming guide device includes:
[0040] The core tube 1 serves as the main frame, supporting the coring drill bit 2 and the guide section 3. The bottom end of the core tube 1 is connected to the coring drill bit 2 for drilling core samples. The coring drill bit 2 is threadedly connected to the core tube 1, which facilitates disassembly and replacement of the coring drill bit to adapt to drilling needs under different geological conditions.
[0041] The guide part 3 includes an inner tube 31 and a guide rod 32. The inner tube 31 is coaxially arranged with the core tube 1 and can move along the axial direction of the core tube 1. The inner tube 31 serves as a support structure for the guide rod 32. Its interior is connected to the core tube 1 through a self-locking part 4 to ensure a fixed connection between the inner tube 31 and the core tube 1.
[0042] Specifically, the self-locking part 4 enables reliable connection and separation between the inner tube 31 and the core tube 1. It includes an expansion core 41 and expansion sleeves 42. The inner tube 31 is provided with a plurality of expansion sleeves 42 that can move radially along the inner tube 31. The upper and / or lower ends of the plurality of expansion sleeves 42 are provided with snap rings 46. The snap rings 46 connect the plurality of expansion sleeves 42. When the expansion core 41 and the expansion sleeves 42 are in the initial state of separation, the snap rings 46 provide elastic force to retract the plurality of expansion sleeves 42 inward to ensure the separation between the self-locking part 4 and the slot part 11.
[0043] The expansion core 41 is slidably disposed inside the inner tube 31 and cooperates with the expansion sleeve 42. The expansion core 41 is located on the upper side of the expansion sleeve 42. The expansion core 41 includes a sliding part 411 and a working part 412. The sliding part 411 is slidably cooperated with the inner wall of the inner tube 31 to ensure the linear movement of the expansion core 41 in the inner tube 31. The working part 412 has a downwardly tapered structure and cooperates with the inner side of the expansion sleeve 42. When the expansion core 41 moves downward, the tapered surface of the working part 412 squeezes the expansion sleeve 42, converting its own axial movement into the radial movement of the expansion sleeve 42, causing it to expand radially outward.
[0044] The inner tube 31 is provided with a limiting ring 34 above the expansion core 41, and the upper end of the expansion core 41 is provided with a thrust spring 44 connected to the limiting ring 34.
[0045] The bottom end of the expansion core 41 is provided with a tension spring 43 connected to the inner tube 31. The inner tube 31 is located below the expansion sleeve 42 and is provided with a connecting plate 35. The two ends of the tension spring 43 are respectively fixedly connected to the expansion core 41 and the connecting plate 35.
[0046] Under normal conditions, the thrust spring 44 and the tension spring 43 cause the expansion core 41 to move downward, pushing the expansion sleeve 42 to expand outward.
[0047] Meanwhile, in actual implementation, slots can be opened on the expansion core 41 and guide rod 32 to form mud flow channels, so that mud can be transported to the drill bit to achieve cooling of the drill bit.
[0048] One end of the guide rod 32 is threaded to the inner tube 31, and the other end is connected to the guide drill bit 33 located outside the core drill bit 2. The guide rod 32 and the guide drill bit 33 are threaded together, guiding the guide drill bit 33 to perform hole enlargement operation outside the core drill bit 2.
[0049] The core tube 1 is provided with a groove 11 that mates with the expansion sleeve 42. The groove 11 includes an annular limiting groove 111 that is formed on the inner wall of the core tube 1 and adapted to the expansion sleeve 42. The annular limiting groove 111 provides axial space to mate with multiple expansion sleeves 42, thereby positioning the expansion sleeve 42 on the core tube 1. The inner side wall of the annular limiting groove 111 is provided with a locking groove 112 that matches the shape of the outer end of the expansion sleeve 42. The locking groove 112 mates with the outer end of the corresponding single expansion sleeve 42 and locks it in place, thereby fixing the expansion sleeve 42 on the core tube 1.
[0050] During implementation, the axial engagement length of the expansion core 41 and the expansion sleeve 42 in the driving engagement state is denoted as L1, which is the axial movement distance required for the conical surface of the working part 412 of the expansion core 41 to contact the inner side of the expansion sleeve 42 and effectively drive it to reach the maximum expansion amount.
[0051] The distance between the limiting ring 34 and the upper abutment surface of the expansion core 41 is denoted as L2, which is the maximum distance that the top of the expansion core 41 can move between the limiting ring 34 when the expansion core 41 and the expansion sleeve 42 are in a driving engagement state and are pulled down.
[0052] The radial engagement length of the expansion sleeve 42 and the slot 11 in the snap-fit engagement state is denoted as L3, which is the radial movement depth required for the outer end of the expansion sleeve 42 to be fully embedded in the locking groove 112.
[0053] Among them, L1>L2>L3, specifically, L1>L2. When the expansion core 41 is pulled up and its top contacts the limiting ring 34, the cone surface of the working part 412 in the expansion core 41 does not perform radial drive on the expansion sleeve 42. At the same time, the bottom end of the expansion core 41 is located inside the expansion sleeve 42 to prevent the expansion core 41 from separating from the expansion sleeve 42.
[0054] When L2 > L3, and the top of the expanding core 41 separates from the limiting ring 34 (moving a distance of L2), the radial expansion of the expanding sleeve 42 causes it to fully embed into the locking groove 112 to a depth of L3, achieving locking between the expanding sleeve 42 and the locking groove 112 (because L2 > L3, the driving displacement provided by the expanding core 41 is sufficient to generate a radial expansion exceeding L3). L2 > L3 ensures that when the expanding core 41 reaches the end of its pull-down stroke, the expanding sleeve 42 is locked into the locking groove 112.
[0055] During implementation:
[0056] When the expansion core 41 is pulled down, the conical surface of the working part 412 in the expansion core 41 begins to drive the expansion sleeve 42 to expand outward;
[0057] When the moving distance of the expansion core 41 is less than L2 but greater than a certain value (this value is when the expansion sleeve 42 begins to contact the locking groove 112), the expansion sleeve 42 begins to embed into the locking groove 112.
[0058] Continue pulling down the expansion core 41 until the moving distance L2 is reached. At this point, the expansion sleeve 42 is fully embedded in the locking groove 112 (i.e., depth L3), achieving reliable locking.
[0059] The core expansion 41 is equipped with a retrieval spearhead 45 connected to a rope. The retrieval spearhead 45 is connected to the rope, and the guide rod 32 and the inner tube 31 are taken out from the core tube 1 from the ground surface through the rope to ensure the integrity of the rock samples to be drilled later. After the samples are taken out, the core drilling operation is performed through the core drill bit 2.
[0060] In specific implementation of this utility model:
[0061] 1) Preparation stage:
[0062] The guide part 3 is lowered into the core tube 1 by a rope. At this time, since the rope is connected to the spearhead 45 at the upper end of the expansion core 41, the expansion core 41 and the expansion sleeve 42 are separated under the gravity of the guide part 3. The retaining spring 46 provides elastic force to make the multiple expansion sleeves 42 contract inward, which can ensure the movement of the inner tube 31 in the core tube 1.
[0063] 2) Positioning Phase:
[0064] When the self-locking part 4 on the inner tube 31 moves to the vicinity of the slot part 11 in the core tube 1, the traction force of the rope on the guide part 3 is released. At this time, the expansion core 41 moves downward under the action of the tension spring 43 and the thrust spring 44, overcoming the contraction elastic force of the retaining spring 46, causing the expansion sleeve 42 to expand outward. When the expansion sleeve 42 moves to the annular limiting groove 111, the expansion sleeve 42 and the annular limiting groove 111 are engaged and fixed. At this time, the outer end of the expansion sleeve 42 and the locking groove 112 are in an unengaged state.
[0065] 3) Lockdown phase:
[0066] When the core tube 1 starts to rotate, the locking groove 112 rotates with the core tube 1. During the rotation of the core tube 1, due to the outward expansion force of the expansion sleeve 42, the expansion sleeve 42 can be aligned with the locking groove 112 to achieve the cooperation between the expansion sleeve 42 and the locking groove 112. This continuously presses the expansion sleeve 42 into the locking groove 112 through the conical surface, thereby achieving a fixed connection between the guide part 3 and the core tube 1.
[0067] 4) Hole enlargement operation:
[0068] After the guide part 3 is firmly locked onto the core tube 1 by the self-locking part 4, the position of the guide drill bit 33 is fixed relative to the core drill bit 2.
[0069] When the drilling rig is started, the drilling pressure and torque are transmitted to the guide drill bit 33 through the drill rod, core tube 1, self-locking part 4, inner tube 31, and guide rod 32.
[0070] The guide drill bit 33 performs hole enlargement operation on the outside of the core drill bit 2, and the guide rod 32 ensures that the guide drill bit 33 rotates coaxially around the core drill bit 2 to enlarge the hole.
[0071] 5) Unlock and remove the guide unit:
[0072] After the hole enlargement operation is completed, guide part 3 needs to be removed for subsequent complete core extraction.
[0073] The spearhead 45 is pulled upward from the ground by a rope. The lifting force of the rope overcomes the compression force of the thrust spring 44 and the tension force of the tension spring 43, causing the expansion core 41 to move upward relative to the inner tube 31.
[0074] As the expansion core 41 moves upward, the radial squeezing effect of its conical working part 412 on the inner side of the expansion sleeve 42 decreases and disappears.
[0075] Under the elastic force of the snap ring 46, multiple expansion sleeves 42 are pulled inward and retracted, and their outer ends disengage from the locking groove 112 and the annular limiting groove 111.
[0076] After the expansion sleeve 42 shrinks, its outer diameter is smaller than the inner diameter of the core tube 1, and the rigid connection between the guide part 3 and the core tube 1 is released.
[0077] By continuing to pull the rope of the retrieval spearhead 45, the entire guide section 3 can be lifted from inside the core tube 1 to the surface.
[0078] 6) Core extraction operation:
[0079] After the guide section 3 is removed, the core drill bit 2 is lowered to the bottom of the hole, and the drilling rig is started to perform routine core sampling. The drilled core sample can smoothly enter and fill the core tube 1, and is eventually extracted intact to the surface.
[0080] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the inventive spirit of the present invention, such designs should fall within the protection scope of the present invention.
Claims
1. A core drilling reaming guide device, characterized in that, include: Core tube (1), the bottom end of which is connected to a core drill bit (2); The guide part (3) includes an inner tube (31) and a guide rod (32). The inner tube (31) is disposed inside the core tube (1) and connected by a self-locking part (4). One end of the guide rod (32) is connected to the inner tube (31), and the other end is connected to the guide drill bit (33) located outside the core drill bit (2). The self-locking part (4) includes an expansion core (41) and an expansion sleeve (42). The inner tube (31) is provided with a plurality of expansion sleeves (42) that can move radially along the inner tube (31). The expansion core (41) is slidably disposed in the inner tube (31) and cooperates with the expansion sleeves (42). The core tube (1) is provided with a groove (11) that cooperates with the expansion sleeves (42). The bottom end of the expansion core (41) is provided with a tension spring (43) connected to the inner tube (31). The inner tube (31) is provided with a limiting ring (34) above the expansion core (41). The upper end of the expansion core (41) is provided with a thrust spring (44) connected to the limiting ring (34). The expansion core (41) is provided with a spearhead (45) connected to a rope.
2. The core drilling reaming guide device according to claim 1, characterized in that: The axial engagement length of the expansion core (41) and the expansion sleeve (42) in the driving engagement state is denoted as L1, the distance between the limiting ring (34) and the upper end abutment surface of the expansion core (41) is denoted as L2, and the radial engagement length of the expansion sleeve (42) and the slot (11) in the snap engagement state is denoted as L3; wherein, L1>L2>L3.
3. The core drilling reaming guide device according to claim 2, characterized in that: The expansion core (41) is located on the upper side of the expansion sleeve (42). The expansion core (41) includes a sliding part (411) and a working part (412). The sliding part (411) slides in cooperation with the inner wall of the inner tube (31). The working part (412) has a tapered structure that tapers downward and cooperates with the inner side of the expansion sleeve (42).
4. The core drilling reaming guide device according to claim 3, characterized in that: The upper and / or lower ends of the plurality of expansion sleeves (42) are provided with snap rings (46).
5. The core drilling reaming guide device according to claim 1, characterized in that: The slot (11) includes an annular limiting groove (111) formed on the inner wall of the core tube (1) and adapted to the expansion sleeve (42). The inner side wall of the annular limiting groove (111) is provided with a locking groove (112) that matches the shape of the outer end of the expansion sleeve (42).
6. The core drilling reaming guide device according to claim 1, characterized in that: The inner tube (31) is provided with a connecting plate (35) below the expansion sleeve (42), and the two ends of the tension spring (43) are fixedly connected to the expansion core (41) and the connecting plate (35) respectively.