Drill rod fishing tool

Abstract

The utility model discloses a drill rod fishing tool, which relates to the technical field of mining machinery and comprises a rod body, a sliding cavity, a sliding block and a driving component. The rod body can enter a pipe hole in the center of the drill rod; the sliding cavity is formed in the peripheral wall of the rod body; the sliding block is installed in the sliding cavity in a sliding mode, the sliding block has a first position and a second position, when the sliding block is located at the first position, the sliding block is completely located in the sliding cavity, and when the sliding block is located at the second position, the sliding block partially stretches out of the sliding cavity and abuts against the inner wall of the pipe hole; the driving assembly is installed on the rod body and used for driving the sliding block to be switched between the first position and the second position. The fishing tool can improve the success rate of fishing the broken drill rod.

Description

Technical Field

[0001] This utility model relates to the field of mining machinery technology, and in particular to a drill pipe retrieval tool. Background Technology

[0002] Drill pipes are used extensively in mining operations and are also very expensive. During drilling, drill pipes may break and fall into the well. Because wells are often over 100 meters deep, and drill pipes are used in combination, they can weigh several tons, making conventional retrieval methods impossible. Traditional drill pipe retrieval methods include wireline retrieval, reverse-thread drill pipe retrieval, and casing taper retrieval. However, these methods often encounter the following problems: limited operating space due to small borehole diameters, complex and variable borehole conditions, small diameter of the broken drill pipe, and insecure fixing of the drill pipe to the retrieval device. These factors result in low success rates and inefficiencies with traditional drill pipe retrieval methods, often requiring multiple attempts to successfully retrieve the broken drill pipe from the borehole, which is time-consuming and labor-intensive. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a drill pipe retrieval tool that can improve the success rate of retrieving broken drill pipes.

[0004] A drill pipe retrieval tool according to a first aspect of the present invention includes: a rod body, a sliding cavity, a slider, and a drive assembly. The rod body can enter a borehole at the center of the drill pipe; the sliding cavity is formed on the outer peripheral wall of the rod body; the slider is slidably installed in the sliding cavity, and the slider has a first position and a second position. When the slider is in the first position, the entire slider is located within the sliding cavity; when the slider is in the second position, a portion of the slider extends out of the sliding cavity and into a tapered hole (211) formed on the inner wall of the borehole (210); the drive assembly is installed on the rod body, and the drive assembly is used to drive the slider to switch between the first position and the second position.

[0005] A drill rod retrieval tool according to an embodiment of this utility model has at least the following advantages: the rod body can smoothly penetrate into the central borehole of the drill rod to be retrieved with the assistance of a drilling rig or lifting equipment. The drive assembly drives the slider to lock the borehole via hydraulic drive, and finally achieves the safe retrieval of the drill rod by lifting the rod body. It has the advantages of low operation difficulty, reliable connection, and high retrieval success rate.

[0006] According to some embodiments of this utility model, the lower end of the rod is narrowed to form a pointed portion.

[0007] According to some embodiments of the present invention, the driving component includes a pressure pump and a water outlet channel. The water outlet channel is formed in the rod body. The pressure pump is connected to the water outlet channel. The water outlet channel is connected to the inner wall of the sliding cavity. The liquid in the water outlet channel can enter the sliding cavity and push the slider to move.

[0008] According to some embodiments of this utility model, a sealing ring is provided between the sliding cavity and the slider.

[0009] According to some embodiments of the present invention, the rod body is connected to a blocking part, the blocking part abuts against the slider located in the second position, and the blocking part is used to prevent the slider from disengaging from the sliding cavity.

[0010] According to some embodiments of this utility model, the inner wall of the tube hole is provided with a tapered hole, and when the slider is in the second position, the slider part extends into the tapered hole.

[0011] According to some embodiments of the present invention, the rod body includes a main rod and a cover plate, the main rod and the cover plate are detachably connected, and the sliding cavity includes a first sliding cavity and a second sliding cavity, the first sliding cavity being formed in the main rod and the second sliding cavity being formed in the cover plate.

[0012] According to some embodiments of this utility model, a sealant is provided between the main rod and the cover plate.

[0013] According to some embodiments of this utility model, the main rod is provided with an installation groove, the cover plate is embedded in the installation groove, and the shape of the cover plate matches the shape of the installation groove.

[0014] According to some embodiments of the present invention, a connecting part is provided at the upper end of the rod body, and the connecting part is used to connect to the drilling rig.

[0015] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0017] Figure 1 This is a schematic diagram of the installation structure of one embodiment of the present utility model;

[0018] Figure 2 This is an exploded view of the cover plate according to one embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram of the main rod explosion according to an embodiment of the present invention;

[0020] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0021] Figure 5 This is a cross-sectional view of the slider in the first position according to an embodiment of the present invention;

[0022] Figure 6 for Figure 5 Enlarged view of point B in the middle;

[0023] Figure 7 This is a cross-sectional view of the slider in the second position according to an embodiment of the present invention;

[0024] Figure 8 for Figure 7 A magnified view of point C in the middle.

[0025] Icon labels:

[0026] Rod body 100, tip 101, blocking part 102, connecting part 103, main rod 110, cover plate 120;

[0027] Drill rod 200, pipe hole 210, tapered hole 211;

[0028] Sliding cavity 300, first sliding cavity 310, second sliding cavity 320;

[0029] Slider 400;

[0030] Drive component 500, pressure pump 510, water outlet channel 520. Detailed Implementation

[0031] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0032] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the accompanying 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, they should not be construed as limitations on this utility model.

[0033] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0034] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0035] Reference Figures 1 to 8As shown, an embodiment of the present invention provides a drill pipe retrieval tool, comprising: a rod body 100, a sliding cavity 300, a slider 400, and a drive assembly 500. The rod body 100 is forged from high-strength alloy steel and has a cylindrical design. The upper end of the rod body 100 is connected to a lifting device or drilling rig to lower the rod body 100 into the wellbore from top to bottom. The outer diameter of the rod body 100 is smaller than the diameter of the central borehole 210 of the drill pipe 200 to be retrieved, allowing the rod body 100 to smoothly penetrate into the central borehole 210 of the drill pipe 200 to be retrieved with the assistance of the drilling rig or lifting device. The sliding cavity 300 is formed on the outer peripheral wall of the rod body 100. The inner surface of the sliding cavity 300 is treated with a mirror polishing process to reduce the friction when the slider 400 moves. Two sliding cavities 300 and sliders 400 are symmetrically arranged. Slider 400 is slidably installed within the sliding cavity 300, and the dimensions of slider 400 match those of the sliding cavity 300. The gap between slider 400 and the sliding cavity 300 is minimized to improve sealing performance. Slider 400 has a first position and a second position. When slider 400 is in the first position, it is completely within the sliding cavity 300, and its outer surface is flush with the contour of rod 100, ensuring smooth movement of rod 100 within the pipe hole 210. The inner wall of the pipe hole 210 is provided with a tapered hole 211. When slider 400 is controlled to move outward to the second position, a portion of slider 400 extends into the tapered hole 211. After slider 400 extends into the tapered hole 211, a more stable connection structure is formed, reliably fixing rod 100 and drill rod 200 axially. It is foreseeable that in actual use, if retrieval fails, the height of the rod 100 within the well should be changed, and then the slider 400 should be re-driven to move to the second position for re-retrieval. The slider 400 extends partially out of the sliding cavity 300 and abuts against the inner wall of the borehole 210; the slider 400 tightly fits against the inner wall of the borehole 210, achieving a rigid connection between the rod 100 and the drill pipe 200 through the combined frictional force generated by the surface texture and contact pressure, thereby driving the drill pipe 200 upwards. The drive assembly 500 is installed on the rod 100 and is used to drive the slider 400 to move precisely within a set stroke, thus switching between the first and second positions. The drive assembly 500 is hydraulic to adapt to the complex downhole environment. The drive assembly 500 hydraulically drives the slider 400 to engage the borehole 210, ultimately achieving the safe lifting of the drill pipe 200 to be retrieved by raising the rod 100.

[0036] Reference Figure 1 and Figure 5 As shown, it can be understood that the lower end of the rod 100 narrows to form a tip 101. The rod 100 is machined to form a tapered tip 101. The tip 101 serves as a guide, allowing the rod 100 to be inserted into the drill pipe 200 even if it is not fully aligned with the drill pipe 200.

[0037] Reference Figure 5 and Figure 7 As shown, the drive assembly 500 includes a pressure pump 510 and a water outlet channel 520. The pressure pump 510 is a plunger pump, typically located on the ground. The pressure pump 510 is connected to the water outlet channel 520 of the rod 100 via a pipe on the drilling rig. The pressure pump 510 pressurizes and delivers water to the water outlet channel 520, which is located within the rod 100. The pressure pump 510 communicates with the water outlet channel 520, which is connected to the inner wall of the sliding cavity 300. Liquid in the water outlet channel 520 can enter the sliding cavity 300 and push the slider 400 to move. By controlling the pressure difference at both ends of the slider 400, the slider 400 can switch between the first position and the second position. It is foreseeable that the outlet of the pressure pump 510 is equipped with a pressure feedback device, which can automatically adjust the speed of the pressure pump 510 according to the pressure at the outlet of the pressure pump 510, so that the liquid pressure in the water outlet channel 520 is kept within a preset range, so that the slider 400 can be kept in the second position, ensuring that the slider 400 and the inner wall of the pipe hole 210 form the best contact stress.

[0038] Reference Figure 4 As shown, a sealing ring is provided between the sliding cavity 300 and the slider 400. The mating surfaces of the slider 400 and the sliding cavity 300 adopt a combined sealing scheme, including a PTFE guide ring and a fluororubber main sealing ring. The PTFE guide ring reduces friction and provides guidance. Through the self-lubricating properties of PTFE, the slider 400 can slide smoothly within the sliding cavity 300. The fluororubber main sealing ring provides a seal, ensuring zero leakage performance under operating conditions. The fluororubber main sealing ring also increases appropriate friction, fixing the slider 400 and keeping it in the first position before it extends into the drill pipe 200.

[0039] Reference Figures 5 to 8 As shown, it can be understood that the sliding cavity 300 is inclined, and the opening size of the sliding cavity 300 on the outer peripheral wall of the rod 100 is smaller than the internal size of the sliding cavity 300, so that only part of the slider 400 can extend out of the sliding cavity 300. The rod 100 is connected to a blocking part 102, which is integrally formed at the opening of the sliding cavity 300. The blocking part 102 abuts against the slider 400 located in the second position. The blocking part 102 is used to prevent the slider 400 from disengaging from the sliding cavity 300.

[0040] Reference Figures 5 to 8 As shown, it can be understood that a chamfer is provided on the upper side of the tapered hole 211. The chamfer abuts against the slider 400. The chamfer is used to increase the contact area between the slider 400 and the inner wall of the hole 210, so as to improve the service life of the slider 400.

[0041] Reference Figures 1 to 4 As shown, the rod 100 includes a main rod 110 and a cover plate 120. The main rod 110 and the cover plate 120 are connected by bolts for easy assembly. The sliding cavity 300 includes a first sliding cavity 310 and a second sliding cavity 320. The first sliding cavity 310 is located on the main rod 110, and the second sliding cavity 320 is located on the cover plate 120. After the main rod 110 and the cover plate 120 are assembled, the first sliding cavity 310 and the second sliding cavity 320 form a complete and continuous sliding cavity 300. This ensures structural integrity and gives the equipment the unique advantage of being detachable and maintainable. Manufacturing the main rod 110 and the cover plate 120 separately facilitates later maintenance and component replacement. Manufacturing the first sliding cavity 310 and the second sliding cavity 320 separately reduces the molding difficulty of the sliding cavity 300.

[0042] Reference Figure 2 As shown, it is understood that a sealant is provided between the main rod 110 and the cover plate 120. The sealant effectively prevents external dust, moisture, and other contaminants from entering the sliding cavity 300, ensuring a clean operating environment for the internal slider 400. It also prevents high-pressure liquid inside the sliding cavity 300 from leaking to the outside. The sealant and the detachable connection structure complement each other, maintaining the advantages of disassembly and assembly while enhancing the protection level of the joints. This extends the service life of the slider 400 and ensures reliable operation of the equipment under harsh conditions such as humidity and dust in drilling operations.

[0043] Reference Figure 2 and Figure 3 As shown, the main rod 110 has a mounting groove located on its outer periphery. The cover plate 120 is embedded in the mounting groove using a contour-fitting structure, and the shape of the cover plate 120 matches the shape of the mounting groove. The mounting groove positions the cover plate 120 during installation, and after installation, the main rod 110 and the cover plate 120 form a complete cylindrical structure, which reduces obstruction when entering the pipe hole 210.

[0044] Reference Figure 1 As shown, it can be understood that a connecting part 103 is welded to the upper end of the rod 100. The connecting part 103 is used to connect the drilling rig. The top of the connecting part 103 is designed with a standard threaded interface, which can be quickly connected to the drilling rig hoisting device, and vertical lowering operation can be achieved with the help of the lifting equipment.

[0045] Operating steps: Measure the depth of the drill rod 200 to be retrieved, connect the connecting part 103 at the upper end of the rod 100 to the drilling rig hoisting device, and lower the rod 100 vertically into the well. After reaching the predetermined depth, the pressure pump 510 injects water into the sliding cavity 300 through the water outlet channel 520, creating a pressure difference on both sides of the slider 400. Control the slider 400 to move from the first position to the second position. The slider 400 extends into the tapered hole 211, forming a stable connection structure, reliably fixing the rod 100 and the drill rod 200 in the axial direction. Then, the drilling rig lifts the rod 100 to safely pull out the drill rod 200 to be retrieved.

[0046] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A drill pipe retrieval tool, characterized in that, include: A rod (100) that can enter the bore (210) at the center of the drill rod (200); A sliding cavity (300) is formed on the outer peripheral wall of the rod (100); A slider (400) is slidably installed in the sliding cavity (300). The slider (400) has a first position and a second position. When the slider (400) is in the first position, the slider (400) is completely located in the sliding cavity (300). When the slider (400) is in the second position, a portion of the slider (400) extends out of the sliding cavity (300) and into the tapered hole (211) opened in the inner wall of the tube hole (210). A drive assembly (500) is mounted on the rod (100) for driving the slider (400) to switch between a first position and a second position.

2. The drill pipe retrieval tool according to claim 1, characterized in that: The lower end of the rod (100) narrows to form a pointed tip (101).

3. The drill pipe retrieval tool according to claim 2, characterized in that: The drive assembly (500) includes a pressure pump (510) and a water outlet channel (520). The water outlet channel (520) is located inside the rod body (100). The pressure pump (510) is connected to the water outlet channel (520). The water outlet channel (520) is connected to the inner wall of the sliding cavity (300). The liquid in the water outlet channel (520) can enter the sliding cavity (300) and push the slider (400) to move.

4. The drill pipe retrieval tool according to claim 3, characterized in that: A sealing ring is provided between the sliding cavity (300) and the slider (400).

5. The drill pipe retrieval tool according to claim 4, characterized in that: The rod (100) is connected to a blocking part (102), which abuts against the slider (400) located in the second position. The blocking part (102) is used to prevent the slider (400) from disengaging from the sliding cavity (300).

6. The drill pipe retrieval tool according to claim 5, characterized in that: The tapered hole (211) has a chamfer on its upper side.

7. The drill pipe retrieval tool according to claim 6, characterized in that: The rod (100) includes a main rod (110) and a cover plate (120), the main rod (110) and the cover plate (120) are detachably connected, and the sliding cavity (300) includes a first sliding cavity (310) and a second sliding cavity (320), the first sliding cavity (310) is opened in the main rod (110), and the second sliding cavity (320) is opened in the cover plate (120).

8. The drill pipe retrieval tool according to claim 7, characterized in that: A sealant is provided between the main rod (110) and the cover plate (120).

9. The drill pipe retrieval tool according to claim 8, characterized in that: The main rod (110) has an installation groove, and the cover plate (120) is embedded in the installation groove. The shape of the cover plate (120) matches the shape of the installation groove.

10. The drill pipe retrieval tool according to claim 9, characterized in that: The upper end of the rod (100) is provided with a connecting part (103), which is used to connect the drilling rig.

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