A type of openable core sampling tube

Abstract

This utility model relates to the field of geological exploration equipment technology, specifically disclosing an openable core sampling tube, including: a top connector, a sampling tube, and a drill bit. The sampling tube includes a casing, the top end of which is detachably connected to the top connector, and the bottom end is fixedly connected to the drill bit. Two symmetrically arranged arc-shaped first half-tubes are slidably arranged inside the casing, and two symmetrically arranged semi-circular second half-tubes are arranged inside the first half-tubes. The second half-tubes are connected to the first half-tubes via positioning components, and the first half-tubes are mounted on the inner wall of the casing via limiting components. This utility model, through a double-level nested opening and closing structure and a vertical axis layout, achieves zero-disturbance core extraction, avoids core contamination and damage associated with traditional core sampling, ensures core integrity and originality, and improves core sampling efficiency and ease of operation.

Description

Technical Field

[0001] This utility model belongs to the field of geological exploration equipment technology, specifically relating to an openable and closable core sampling tube. Background Technology

[0002] In the field of engineering exploration, core sampling tubes are the core tool for obtaining underground rock and soil samples. They are mainly used during drilling to collect columnar rock cores for analyzing stratigraphic structure, geological characteristics, and resource distribution. A typical structure includes a drill bit, a core tube, and a top connector: the drill bit cuts through the strata to form a borehole, the core tube holds the collected core samples, and the top connector connects to the drilling equipment via a rotator, driving the entire device to complete the drilling operation. This structure is widely used in building foundation exploration, mineral resource exploration, and environmental geological surveys, and its performance directly affects the core recovery rate, sample integrity, and the accuracy of subsequent analysis results.

[0003] In existing technologies, core tubes and drill bits are mostly designed as an integral or threaded connection. After drilling, the conventional method for removing the core is to tap the core tube to detach it. However, when dealing with highly cohesive soils (such as clay and silty clay), the core adheres tightly to the inner wall of the core tube due to its high water content and strong adhesion, making tapping ineffective and preventing direct removal. In such cases, mud circulation is commonly used to flush the inside of the core tube to force the core out. However, impurities carried by the mud can contaminate the original structure of the core, leading to distorted data in subsequent geotechnical tests (such as water content and density tests). Moreover, the flushing process requires continuous pumping of mud, which is time-consuming and energy-intensive, especially in deep drilling where mud consumption and equipment energy consumption increase significantly. Furthermore, repeated flushing may damage the bedding characteristics of the core, blurring geological stratification interfaces and affecting the accuracy of stratigraphic division. Utility Model Content

[0004] The purpose of this invention is to provide an openable and closable core sampling tube to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] An openable core sampling tube, comprising:

[0007] Top connector, sampling tube and drill bit, wherein the sampling tube includes a sleeve, the top end of which is detachably connected to the top connector and the bottom end is fixedly connected to the drill bit;

[0008] The sleeve has two symmetrically arranged arc-shaped first half-tubes inside, and two symmetrically arranged semi-circular second half-tubes inside the first half-tubes.

[0009] The second half-tube is connected to the first half-tube via a positioning component, and the first half-tube is mounted on the inner wall of the sleeve via a limiting component.

[0010] Preferably, the axes of symmetry of the two first half-tubes are perpendicular to the axes of symmetry of the two second half-tubes.

[0011] Preferably, the limiting component includes a fixing strip fixedly disposed on the inner wall of the sleeve, the fixing strip extending to form a partition between the two first half tubes, and a limiting piece fixedly disposed on its inner side wall, the limiting piece being arc-shaped, and its outer side wall being in contact with the inner side wall of the first half tube.

[0012] Preferably, the positioning component includes two locking pieces symmetrically fixed on the outer wall of the second half-tube. The locking pieces have a U-shaped cross-section. The inner wall of the first half-tube and the two locking pieces are respectively provided with L-shaped locking grooves. The locking pieces can be slidably inserted into the locking grooves.

[0013] Preferably, the outer side wall of the top end of the sleeve is provided with a first external thread, and the inner side wall of the bottom end of the top connector is provided with a first internal thread that matches the first external thread.

[0014] Preferably, the inner sidewall of the top end of the top connector is provided with a second internal thread for an external rotator.

[0015] Preferably, the inner wall of the top connector is provided with a connecting wall, the diameter of which is the same as the diameter of the first half-pipe.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] (1) Through the orthogonal symmetrical design of the first half-tube and the second half-tube and the detachable connection structure, the originality and integrity of the rock core are effectively guaranteed. When taking the core, the half-tube can be separated in two vertical directions in stages, avoiding the problems of rock core contamination and stratification damage caused by knocking or mud erosion in the existing technology. It is especially suitable for cohesive soil, and can completely preserve the natural structure and physical properties of the rock core, providing accurate samples for subsequent geological analysis.

[0018] (2) The limiting component achieves stable sliding and precise positioning of the first half tube through thin limiting piece and fixing strip. The positioning component achieves quick disassembly and assembly of the second half tube by means of U-shaped locking piece and L-shaped snap-fit ​​groove with the same thickness as the limiting piece. The two work together to make the half tube separation and reset operation simple, without relying on additional flushing equipment, thus improving the convenience and efficiency of core taking operation. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present utility model;

[0020] Figure 2 This is a side cross-sectional view of the present invention;

[0021] Figure 3 This is a top cross-sectional view of the present invention;

[0022] Figure 4 This is a perspective view of the limiting component of this utility model;

[0023] Figure 5 This is a perspective view of the top connector of this utility model;

[0024] Figure 6 This is a perspective view of the first half-tube of this utility model;

[0025] Figure 7 This is a perspective view of the second half-tube of this utility model;

[0026] In the diagram: 1. Top connector; 2. Sampling tube; 3. Drill bit; 4. First half-tube; 5. Second half-tube; 6. Locking plate;

[0027] 11. First internal thread; 12. Connecting wall; 13. Second internal thread; 21. Sleeve; 22. First external thread; 23. Fixing strip; 24. Limiting piece; 41. Snap-fit ​​groove. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and 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, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. Example 1:

[0030] Please see Figures 1-7 As shown, an openable core sampling tube includes:

[0031] Top connector 1, sampling tube 2 and drill bit 3, the sampling tube 2 includes a sleeve 21, the top end of which is detachably connected to the top connector 1 and the bottom end is fixedly connected to the drill bit 3;

[0032] The sleeve 21 has two symmetrically arranged arc-shaped first half-tubes 4 inside, and two symmetrically arranged semi-circular second half-tubes 5 inside the first half-tubes 4.

[0033] The second half-tube 5 is connected to the first half-tube 4 via a positioning component, and the first half-tube 4 is installed on the inner wall of the sleeve 21 via a limiting component.

[0034] Depend on Figure 5 As shown, the outer side wall of the top end of the sleeve 21 is provided with a first external thread 22, and the inner side wall of the bottom end of the top connector 1 is provided with a first internal thread 11 that is adapted to the first external thread 22.

[0035] The inner sidewall of the top of the top connector 1 is provided with a second internal thread 13 for an external rotator;

[0036] The inner wall of the top connector 1 is provided with a connecting wall 12, the diameter of which is the same as the diameter of the first half-pipe 4.

[0037] As can be seen from the above, the top connector 1 is detachably connected to the first external thread 22 at the top of the sleeve 21 via the first internal thread 11 at the bottom end, and the second internal thread 13 at the top end is used to connect the rotator, thereby driving the entire device to rotate, and cooperating with the drill bit 3 fixedly connected at the bottom end to cut the formation and form a borehole.

[0038] The arc-shaped first half-tube 4, symmetrically arranged inside the sleeve 21, slides along the inner wall of the sleeve 21 through the limiting component, while the semi-circular second half-tube 5 nested inside it is fixed to the first half-tube 4 through the positioning component and moves synchronously with it.

[0039] During drilling, the first half-tube 4 drives the second half-tube 5 to close, forming a complete sampling chamber. The rock core enters the second half-tube 5 after being cut by the drill bit 3.

[0040] After the drill string is lifted, the first half-tube 4 can be slid out along the casing 21 by disassembling the top joint 1, and then the second half-tube 5 can be separated by the positioning component. This achieves zero-push disturbance core sampling, avoiding problems such as core contamination, structural damage and low efficiency caused by knocking or mud scouring in traditional technology, ensuring the integrity and originality of the core, and improving sampling effect and operation efficiency.

[0041] The diameter of the connecting wall 12 inside the top connector 1 is the same as that of the first half-pipe 4, ensuring that the rock core can smoothly and unobstructedly transition from the first half-pipe 4 to the top connector 1.

[0042] Specifically, regarding the above, please refer to... Figure 3 and Figure 4As shown, the limiting component includes a fixing strip 23 fixedly disposed on the inner wall of the sleeve 21. The fixing strip 23 extends to form a partition between the two first half tubes 4. A limiting piece 24 is fixedly disposed on its inner side wall. The limiting piece 24 is arc-shaped, and its outer side wall is in contact with the inner side wall of the first half tube 4.

[0043] As can be seen from the above, the fixing strip 23 is fixedly installed on the inner wall of the casing 21, and extends to form a physical separation between the two first half-tubes 4. This can prevent the two first half-tubes 4 from squeezing or colliding with each other during the sliding process, ensuring that the two can move independently and smoothly. At the same time, the arc-shaped limiting piece 24 on the inner side wall of the fixing strip 23 is relatively thin, and its outer side wall fits against the inner side wall of the first half-tube 4. This thin arc-shaped fitting design can not only provide radial support for the first half-tube 4 and limit its radial displacement in the casing 21, but also minimize the gap between the two, prevent rock core debris from entering the gap and hindering the sliding or causing the half-tube to get stuck. At the same time, it guides the first half-tube 4 to slide stably along the inner wall of the casing 21, ensuring that the first half-tube 4 always maintains coaxiality with the casing 21 during drilling or core sampling, and avoids damage to the rock core and the inner wall of the half-tube due to shaking or gap squeezing. This limiting component significantly improves the structural stability and smooth sliding of the first half-tube 4 through the dual functions of separation and thin fitting, ensuring that the core remains intact during the containment process and laying the foundation for the subsequent successful extraction of the core.

[0044] Specifically, regarding the above, please refer to... Figure 3 , Figure 6 and Figure 7 As shown, the positioning component includes two locking pieces 6 symmetrically fixed on the outer wall of the second half tube 5. The locking pieces 6 have a U-shaped cross section. The inner wall of the first half tube 4 has L-shaped locking grooves 41 at the corresponding positions of the two locking pieces 6. The locking pieces 6 can be slidably inserted into the locking grooves 41.

[0045] As can be seen from the above, the U-shaped locking plate 6, which is symmetrically fixed on the outer wall of the second half-tube 5, has the same thickness as the limiting plate 24 and is relatively thin. It can accurately correspond to the L-shaped locking groove 41 opened on the inner wall of the first half-tube 4 and slide along it. The U-shaped locking plate 6 can enhance the fit stability with the locking groove 41. The thinner thickness can reduce the fit gap between the first half-tube 4 and the second half-tube 5, and prevent rock core debris from entering the gap and hindering the sliding or causing the half-tube to get stuck. The L-shaped locking groove 41 can also limit the locking plate 6 in the axial and radial directions, ensuring that the second half-tube 5 and the first half-tube 4 are tightly combined into a complete inner rock core structure during drilling, and preventing the rock core from being damaged due to the loosening of the half-tube during drilling vibration. When it is necessary to remove the rock core, the locking plate 6 can be disengaged from the locking groove 41 by sliding in the opposite direction, thereby separating the two second half-tubes 5 and directly removing the internal rock core. The positioning component, with its sliding and detachable structure, not only ensures the stable containment of the rock core during the coring process, but also enhances the smoothness of sliding with its thin design consistent with the limiting plate 24, enabling rapid separation of the half-tube to remove the rock core without damage, effectively protecting the originality and integrity of the rock core. Example 2:

[0046] refer to Figure 3 It can be seen that the axes of symmetry of the two first half-tubes 4 are perpendicular to the axes of symmetry of the two second half-tubes 5.

[0047] As shown above, the axes of symmetry of the two first half-tubes 4 are perpendicular to the axes of symmetry of the two second half-tubes 5. This orthogonal symmetry design allows the two to form a complete cylindrical core space in the closed state, ensuring that the core can be stably encased inside during drilling. When taking the core, it can be separated first along the axis of symmetry of the first half-tube 4, and then along the axis of symmetry of the second half-tube 5, or vice versa. Through the opening and closing actions in two perpendicular directions, the forced pulling on the viscous core during opening and closing in one direction is avoided. Compared with the existing technology where the core tubes are mostly single-axis opening and closing or integral structures, the core is prone to fracture and bedding damage due to the strong adhesion between the core and the tube wall during core taking. This orthogonal symmetry design can reduce the compression and friction on the core through step-by-step separation, so that the core always maintains its original shape and bedding structure during the extraction process, effectively ensuring the integrity of the core and providing a more accurate sample basis for subsequent geological analysis.

[0048] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An openable core barrel, characterized in that, include: Top connector (1), sampling tube (2) and drill bit (3), wherein the sampling tube (2) includes a sleeve (21), the top end of which is detachably connected to the top connector (1) and the bottom end is fixedly connected to the drill bit (3); The sleeve (21) has two symmetrically arranged arc-shaped first half tubes (4) inside, and two symmetrically arranged semi-circular second half tubes (5) are provided inside the first half tubes (4). The second half-tube (5) is connected to the first half-tube (4) by a positioning component, and the first half-tube (4) is installed on the inner wall of the sleeve (21) by a limiting component.

2. An openable core barrel according to claim 1, wherein: The axes of symmetry of the two first half tubes (4) are perpendicular to the axes of symmetry of the two second half tubes (5).

3. An openable core barrel according to claim 1, wherein: The limiting component includes a fixing strip (23) fixedly disposed on the inner wall of the sleeve (21). The fixing strip (23) extends to form a separation between the two first half tubes (4). A limiting piece (24) is fixedly disposed on its inner side wall. The limiting piece (24) is arc-shaped, and its outer side wall is in contact with the inner side wall of the first half tube (4).

4. An openable core barrel according to claim 1, wherein: The positioning component includes two locking pieces (6) symmetrically fixed on the outer wall of the second half tube (5). The locking pieces (6) have a U-shaped cross section. The inner wall of the first half tube (4) and the corresponding positions of the two locking pieces (6) are respectively provided with L-shaped locking grooves (41). The locking pieces (6) can be slidably inserted into the locking grooves (41).

5. An openable core barrel according to claim 1, wherein: The outer side wall of the top end of the sleeve (21) is provided with a first external thread (22), and the inner side wall of the bottom end of the top connector (1) is provided with a first internal thread (11) that is compatible with the first external thread (22).

6. The openable and closable core sampling tube according to claim 1, characterized in that: The inner wall of the top of the top of the top connector (1) is provided with a second internal thread (13) for an external rotator.

7. The openable and closable core sampling tube according to claim 4, characterized in that: The inner wall of the top connector (1) is provided with a connecting wall (12), the diameter of which is the same as the diameter of the first half-pipe (4).

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