Composite core claw

Abstract

The present application relates to the field of oil coring, and particularly relates to a composite core claw, aiming at relieving the technical problem of easy core falling during coring in the related art. The composite core claw comprises a connecting seat, the inside of the connecting seat is provided with a sliding channel extending along the axial direction of the connecting seat; a guide hoop is in the connecting seat and is in sliding cooperation with the connecting seat through the sliding channel, the guide hoop can contract or expand along the radial direction of the guide hoop during the sliding process; a wear-resistant block is arranged on the inner wall of the guide hoop and extends from one end of the guide hoop to the other end, and is also distributed along the circumferential direction of the guide hoop. The wear-resistant block of the composite core claw has a larger contact area with the core, the friction between the guide hoop and the core under the contraction working condition is increased, so that the core can be effectively held, and the coring operation is completed.

Description

Technical Field

[0001] This invention relates to the field of petroleum core sampling, and more particularly to a composite core claw. Background Technology

[0002] During the core drilling process, due to the variable lithology of the formation, the core claws of existing core drilling tools are prone to losing their grip on the core during core cutting. Summary of the Invention

[0003] The purpose of this invention is to provide a composite core claw to alleviate the technical problem of core loss during core cutting in related technologies.

[0004] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0005] The composite core claw provided by the present invention includes: a connecting seat, wherein the connecting seat is provided with a slide extending along its own axial direction;

[0006] A guide clamp is located inside the connecting seat and slides with the connecting seat through the slide rail. The guide clamp can contract or expand radially during sliding.

[0007] Wear-resistant blocks are disposed on the inner wall of the guide clamp and extend from one end of the guide clamp to the other end, and are also distributed along the circumference of the guide clamp.

[0008] Furthermore, the guide clamp is C-shaped, and its outer wall engages with the inner wall of the connecting seat via a conical surface.

[0009] Furthermore, the composite core claw also includes a core-taking sleeve, which is also C-shaped and is disposed inside the guide clamp;

[0010] The wear-resistant block is formed on the inner wall of the core-taking sleeve.

[0011] Furthermore, the core-taking sleeve is detachably connected to the guide clamp.

[0012] Furthermore, the wear-resistant block extends in a spiral shape.

[0013] Furthermore, the wear-resistant block has multiple spiral heads.

[0014] Furthermore, the wear-resistant block extends in a straight line.

[0015] Furthermore, the connecting seat includes a connecting sleeve and a guide seat;

[0016] The connecting sleeve is fixedly connected to the guide bracket;

[0017] The slide is formed between the connecting sleeve and the guide seat.

[0018] Furthermore, one end of the connecting sleeve is located within the guide bracket;

[0019] The guide clamp is located inside the guide seat and engages with the guide seat through a conical surface. Its large-diameter end is located between the outer wall of the connecting sleeve and the inner wall of the guide seat, while its small-diameter end extends beyond the connecting sleeve.

[0020] Furthermore, the connecting sleeve is threadedly connected to the guide seat.

[0021] In summary, the composite core claw provided by this invention achieves the following technical effects:

[0022] In this composite core claw, the guide clamp can slide along the slide rail within the connecting seat, with the two ends of the slide rail being the first end and the second end, respectively. As the guide clamp slides from the first end to the second end, it contracts radially. Conversely, as it slides from the second end to the first end, it expands radially. The wear-resistant blocks extend from one end of the guide clamp to the other end and are also distributed circumferentially along the guide clamp. Thus, as the guide clamp contracts, the contact area between the wear-resistant blocks and the core is relatively large.

[0023] During the coring operation, as the drilling progresses deeper, the core forces the guide clamp to move upward, i.e., slide from the second end to the first end, opening the guide clamp and entering its interior. When the drilling reaches the required position and the core length is reached, the core is cut by lifting it up. During the lifting process, the friction between the wear-resistant block and the core forces the guide clamp to move downward. The guide clamp slides from the first end to the second end, gradually tightening and holding the core tightly through the wear-resistant block. When the friction increases to a level greater than the force that the core can withstand, the core cutting is completed.

[0024] It can be seen that the wear-resistant block of the composite core claw has a large contact area with the core, which increases the friction between the guide clamp and the core under shrinkage conditions, thus effectively holding the core and completing the core cutting operation. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 A cross-sectional view of one embodiment of the composite core claw provided in this invention;

[0027] Figure 2 A cross-sectional view of another embodiment of the composite core claw provided in this invention;

[0028] Figure 3 This is a schematic diagram of the structure of one embodiment of the core-taking component provided in this invention;

[0029] Figure 4 A schematic diagram of another embodiment of the core-taking component provided in this invention;

[0030] Figure 5 This is a schematic diagram of the guide clamp provided in an embodiment of the present invention;

[0031] Figure 6 for Figure 3 Schematic diagram of the structure of the center-removing sleeve;

[0032] Figure 7 for Figure 4 A schematic diagram of the structure of the center-removing sleeve.

[0033] Icons: 100 - Connector; 110 - Connector Sleeve; 120 - Guide Card;

[0034] 200 - Guide clamp; 300 - Wear-resistant block; 400 - Core sleeve. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0037] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0038] During the core drilling process, due to the variable lithology of the formation, the core claws of existing core drilling tools are prone to losing their grip on the core during core cutting.

[0039] In view of this, the present invention provides a composite core claw, including a connecting seat 100 and a guide clamp 200 coaxially arranged with the connecting seat 100; the connecting seat 100 is a cylindrical shape with open ends, and has a slide rail extending along its own axial direction inside, the slide rail having a first end and a second end in opposite directions; the guide clamp 200 is located inside the connecting seat 100 and slides with the connecting seat 100 through the slide rail, the guide clamp 200 can contract radially during the sliding process from the first end to the second end, and expand radially during the sliding process from the second end to the first end; the inner wall of the guide clamp 200 is provided with wear-resistant blocks 300, the wear-resistant blocks 300 extend from one end of the guide clamp 200 to the other end, and are also distributed along the circumference of the guide clamp 200.

[0040] In this composite core claw, the guide clamp 200 can slide along the slide rail within the connecting seat 100, and during the process of sliding from the first end to the second end, it contracts radially. Conversely, during the process of sliding from the second end to the first end, it expands radially. The wear-resistant block 300 extends from one end of the guide clamp 200 to the other end and is also distributed circumferentially along the guide clamp 200. Thus, when the guide clamp 200 contracts, the contact area between the wear-resistant block 300 and the core is large.

[0041] During the core extraction operation, as the drilling progresses deeper, the core forces the guide clamp 200 to move upward, i.e., slide from the second end to the first end, opening the guide clamp 200 and entering its interior. When the drilling reaches the required position and the core length is reached, the core is extracted by lifting. During the extraction process, the friction between the wear-resistant block 300 and the core forces the guide clamp 200 to move downward. The guide clamp 200 slides from the first end to the second end, gradually tightening and holding the core tightly through the wear-resistant block 300. When the friction increases to a level greater than the force that the core can withstand, the core extraction is completed.

[0042] It can be seen that the wear-resistant block 300 of the composite core claw has a large contact area with the core, which increases the friction between the guide clamp 200 and the core under shrinkage conditions, thus effectively holding the core and completing the core cutting operation.

[0043] The following combination Figures 1 to 7 The structure and shape of the composite core claw provided in this embodiment are described in detail:

[0044] In this embodiment, reference Figures 1 to 3The connecting seat 100 includes a connecting sleeve 110 and a guide seat 120; the bottom end of the connecting sleeve 110 is inside the guide seat 120, and the connecting sleeve 110 and the guide seat 120 are threadedly connected; the guide clamp 200 is C-shaped, with its top end located between the outer wall of the connecting sleeve 110 and the inner wall of the guide seat 120, and its bottom end located below the connecting sleeve 110. Its outer wall and the guide seat 120 are engaged by a conical surface, and the diameter of the conical surface gradually decreases from top to bottom.

[0045] When performing the core extraction operation, with Figure 1 For example, as the core is drilled deeper, the core forces the guide clamp 200 to move upward to its upper limit position, that is, the threaded connection between the connecting sleeve 110 and the guide seat 120, thus opening the guide clamp 200 and allowing it to enter the guide clamp 200; when the drilling reaches the required position and the core length is required, the core is cut upward; the friction between the wear-resistant block 300 and the core forces the guide clamp 200 to move downward, and the conical surface of the guide seat 120 forces the guide clamp 200 to tighten and hold the core; the friction between the wear-resistant block 300 and the core gradually increases, and when it exceeds the force that the core can withstand, the core cutting is completed.

[0046] refer to Figure 3 and Figure 6 Optionally, the wear-resistant block 300 extends in a spiral shape, and the spiral head has at least one end; Reference Figure 4 and Figure 7 Optionally, the wear-resistant block 300 extends in a straight line and is provided with multiple strips.

[0047] Using the above design, different shapes of wear-resistant blocks 300 and the corresponding number of wear-resistant blocks 300 can be selected according to different rock types, so as to maximize the contact area between the rock core and the rock core claw, i.e., the wear-resistant block 300.

[0048] To facilitate the replacement of the wear-resistant block 300, in this embodiment, refer to Figures 3 to 7 The composite core claw also includes a core sleeve 400, which is also C-shaped and is set inside the guide clamp 200, forming a core assembly together with the guide clamp 200; the wear-resistant block 300 is formed on the inner wall of the core sleeve 400.

[0049] Specifically, the inner wall of the guide clamp 200 is provided with two limiting steps. The core sleeve 400 is coaxially arranged with the guide clamp 200 and positioned between the two limiting steps to achieve engagement with the guide clamp 200. With this design, the core sleeve 400 and the guide clamp 200 are detachably connected. Depending on different rock types, core sleeves 400 with different wear-resistant blocks 300 can be selected to form different core-taking components with the guide clamp 200, thereby effectively cutting the rock core and completing the core-taking operation.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A composite core claw, characterized in that, include: A connecting seat (100) is provided inside which a slide rail extends along its own axial direction; a guide clamp (200) is located inside the connecting seat (100) and slides with the connecting seat (100) through the slide rail, and the guide clamp (200) can contract or expand along its own radial direction during sliding; a wear-resistant block (300) is disposed on the inner wall of the guide clamp (200) and extends from one end of the guide clamp (200) to the other end, and is also distributed along the circumference of the guide clamp (200).

2. The composite core claw according to claim 1, characterized in that, The guide clamp (200) is C-shaped, and its outer wall is engaged with the inner wall of the connecting seat (100) through a conical surface.

3. The composite core claw according to claim 2, characterized in that, The composite core claw also includes a core-taking sleeve (400), which is also C-shaped and is located inside the guide clamp (200); The wear-resistant block (300) is formed on the inner wall of the core-taking sleeve (400).

4. The composite core claw according to claim 3, characterized in that, The core-taking sleeve (400) and the guide clamp (200) are detachably connected.

5. The composite core claw according to claim 1, characterized in that, The wear-resistant block (300) extends in a spiral shape.

6. The composite core claw according to claim 5, characterized in that, The wear-resistant block (300) has multiple spiral heads.

7. The composite core claw according to claim 1, characterized in that, The wear-resistant block (300) extends in a straight line.

8. The composite core claw according to any one of claims 2 to 7, characterized in that, The connecting seat (100) includes a connecting sleeve (110) and a guide seat (120); The connecting sleeve (110) is fixedly connected to the guide bracket (120); The slide is formed between the connecting sleeve (110) and the guide seat (120).

9. The composite core claw according to claim 8, characterized in that, One end of the connecting sleeve (110) is located inside the guide seat (120); The guide clamp (200) is located inside the guide seat (120) and engages with the guide seat (120) through a conical surface. Its large-diameter end is located between the outer wall of the connecting sleeve (110) and the inner wall of the guide seat (120), while its small-diameter end extends beyond the connecting sleeve (110).

10. The composite core claw according to claim 9, characterized in that, The connecting sleeve (110) is threadedly connected to the guide seat (120).

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