Oil casing inner wall file-like machining tool

Abstract

This invention discloses a file-like machining tool for the inner wall of casing and tubing, comprising a central tie rod. One end of the central tie rod has a lower connecting thread on its outer wall, and the other end has an upper connecting thread on its outer wall. A limiter and a counterweight sleeve are fitted onto the central tie rod. The counterweight sleeve is engaged with a chuck, and a chuck fixing ring is fitted onto the outer wall of the chuck. A carbide block unit is fixed to the chuck. This file-like machining tool for the inner wall of casing and tubing solves the problem of difficulty in retrieving downhole chokes due to low friction between the inner wall of the casing and tubing and the downhole choke during existing downhole choke operations.

Description

Technical Field

[0001] This invention belongs to the technical field of oil and gas field development equipment, specifically relating to a file-like machining tool for the inner wall of oil casing. Background Technology

[0002] In oil and gas field wells, downhole tubing and casing are typically required to have smooth inner walls to reduce the friction coefficient between the fluid and the inner wall of the tubing or casing, thereby reducing resistance to fluid flow. However, in some special applications, such as downhole choke operations, approximately 10%-15% of downhole chokes are difficult to retrieve each year. This necessitates machining the smooth inner wall of the tubing and casing into a file-like shape to increase the friction between the sealing rubber of the downhole choke and the inner wall of the tubing, as well as the filing ability of the tubing and casing inner wall. This facilitates the retrieval of the downhole choke, saving time, labor, and costs. Summary of the Invention The purpose of this invention is to provide a file-like machining tool for the inner wall of the casing, which solves the problem of difficulty in retrieving downhole chokes due to the low friction between the inner wall of the casing and the downhole choke in existing downhole choke operations.

[0003] The technical solution adopted in this invention is a file-like machining tool for the inner wall of an oil casing pipe, including a central pull rod. One end of the central pull rod has a lower connecting thread on its outer wall, and the other end of the central pull rod has an upper connecting thread on its outer wall. A limiter and a counterweight sleeve are fitted on the central pull rod. The counterweight sleeve is engaged with a pawl. A pawl fixing ring is fitted on the outer wall of the pawl. A hard alloy block unit is fixedly connected to the pawl.

[0004] The invention is further characterized by: The limit switch, counterweight sleeve, chuck, and carbide block unit are arranged sequentially from the lower connecting thread to the upper connecting thread.

[0005] The central tie rod has several pin holes, and the limiter is fixed to the central tie rod through pins in the pin holes.

[0006] The central tie rod includes a first straight section rod body, with a lower connecting thread at one end of the first straight section rod body, and a gradually expanding section rod body and a second straight section rod body fixed to the other end of the first straight section rod body in sequence, with an upper connecting thread at the other end of the second straight section rod body.

[0007] Both the limiter and the counterweight sleeve are located on the outer wall of the first straight section of the rod. One end of the claw is engaged with the counterweight sleeve on the outer wall of the first straight section of the rod, and the other end of the claw is fixed to the hard alloy block unit on the outer wall of the gradually expanding section of the rod. The cemented carbide block unit comprises several cemented carbide blocks, which are fixed to the outer wall of the chuck along the circumferential direction.

[0008] The cemented carbide blocks are fixed to the chucks by either embedding or welding.

[0009] The beneficial effects of this invention are: The file-like machining tool for the inner wall of oil casing and tubing provided by this invention performs file-like surface machining on the inner wall of the oil tubing and casing in the vertical section of oil and gas fields, increasing the surface roughness of the inner wall of the oil tubing and casing, thereby increasing the friction between the inner wall of the oil tubing and the downhole choke, facilitating the retrieval of the downhole choke. This invention can selectively machine one or more locations on the inner wall of the oil casing and tubing into a file-like inner wall, and has the characteristics of simple operation and accurate positioning. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of the file-like machining tool for the inner wall of the oil casing of the present invention.

[0011] In the diagram, 1. Lower connecting thread, 2. Limiter, 3. Pin, 4. Central tie rod, 401. First straight section of rod, 402. Gradually expanding section of rod, 403. Second straight section of rod, 5. Counterweight sleeve, 6. Claw, 7. Claw retaining ring, 8. Carbide block, 9. Pin hole, 10. Upper connecting thread. Detailed Implementation

[0012] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0013] The oil casing inner wall processing tool provided by this invention, such as... Figure 1As shown, the device includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end has an upper connecting thread 10 on its outer wall. The upper connecting thread 10 is mainly used to connect with other special tools for well testing wire or logging cable. A limiter 2 and a counterweight sleeve 5 are fitted on the central tie rod 4. The counterweight sleeve 5 is engaged with a chuck 6. The counterweight sleeve 5 mainly relies on its own weight to pull the chuck 6, keeping the chuck 6 in a retracted state. A chuck fixing ring 7 is fitted on the outer wall of the chuck 6 to prevent the chuck 6 from coming out of its assembly position. A hard alloy block unit is fixedly connected to the chuck 6. The limiter 2, counterweight sleeve 5, chuck 6, and hard alloy block unit are arranged sequentially along the direction from the lower connecting thread 1 to the upper connecting thread 10. The central tie rod 4 has several pin holes 9. The limiter 2 is fixedly connected to the central tie rod 4 in the several pin holes 9 by pins 3. The central tie rod 4 includes the first... A straight section rod 401 has a lower connecting thread 1 at one end. A gradually expanding section rod 402 and a second straight section rod 403 are sequentially fixed to the other end of the first straight section rod 401. An upper connecting thread 10 is located at the other end of the second straight section rod 403. A limiter 2 and a counterweight sleeve 5 are both located on the outer wall of the first straight section rod 401. One end of a claw 6 engages with the counterweight sleeve 5 on the outer wall of the first straight section rod 401. The other end of the 6 is fixed to the outer wall of the gradually expanding section rod 402 with a cemented carbide block unit; the cemented carbide block unit includes several cemented carbide blocks 8, which are fixed to the outer wall of the claw 6 along the circumferential direction; the cemented carbide blocks 8 and the claw 6 are fixed by either inlay or welding. The main function of the cemented carbide blocks 8 is to contact the inner surface of the oil casing and to scratch file-like machining marks on the inner surface of the oil casing.

[0014] The working principle of the file-like machining tool for the inner wall of the casing and tubing provided by this invention is as follows: the test wire or cable is connected to the central tie rod 4 through the upper connecting thread 10. After the test wire or cable is lowered into the casing and tubing of the oil and gas well to a predetermined depth, the test wire or logging cable is quickly lowered. The central tie rod 4 moves downward under the action of gravity, and the claws 6, which are embedded or welded with hard alloy 8, come into contact with the inner wall of the casing and tubing. Under the action of friction, the claws 6 move upward along the gradually expanding section 402 of the central tie rod 4 and embed into the inner surface of the casing and tubing, forming file-like machining marks on the inner surface of the casing and tubing. By repeating this up and down motion, a dense file-like surface can be formed at a predetermined position on the inner wall of the casing and tubing, thus achieving the ultimate purpose of this tool: increasing the friction between the sealing rubber of the downhole choke and the inner wall of the tubing and the filing ability of the inner wall of the casing and tubing, making it easier to retrieve the downhole choke.

[0015] Example 1 The oil casing inner wall processing tool proposed in this embodiment is a file-like tool, such as... Figure 1As shown, it includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end of the central tie rod 4 has an upper connecting thread 10 on its outer wall. A limiter 2 and a counterweight sleeve 5 are fitted on the central tie rod 4. The counterweight sleeve 5 is engaged with a claw 6. A claw fixing ring 7 is fitted on the outer wall of the claw 6. A hard alloy block unit is fixedly connected to the claw 6.

[0016] Example 2 The oil casing inner wall processing tool proposed in this embodiment is a file-like tool, such as... Figure 1 As shown, it includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end of the central tie rod 4 has an upper connecting thread 10 on its outer wall. A limiter 2 and a counterweight sleeve 5 are fitted on the central tie rod 4. A claw 6 is engaged with the counterweight sleeve 5. A claw fixing ring 7 is fitted on the outer wall of the claw 6. A hard alloy block unit is fixed to the claw 6. The limiter 2, the counterweight sleeve 5, the claw 6, and the hard alloy block unit are arranged sequentially along the direction from the lower connecting thread 1 to the upper connecting thread 10.

[0017] Example 3 The oil casing inner wall processing tool proposed in this embodiment is a file-like tool, such as... Figure 1 As shown, the device includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end of the central tie rod 4 has an upper connecting thread 10 on its outer wall. A limiter 2 and a counterweight sleeve 5 are fitted onto the central tie rod 4. The counterweight sleeve 5 is engaged with a claw 6. A claw fixing ring 7 is fitted onto the outer wall of the claw 6. A hard alloy block unit is fixedly connected to the claw 6. The limiter 2, the counterweight sleeve 5, the claw 6, and the hard alloy block unit are arranged sequentially along the direction from the lower connecting thread 1 to the upper connecting thread 10. The central tie rod 4 has several pin holes 9. The limiter 2 is fixedly connected to the central tie rod 4 through pins 3 in the several pin holes 9.

[0018] Example 4 The oil casing inner wall processing tool proposed in this embodiment is a file-like tool, such as... Figure 1 As shown, the device includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end has an upper connecting thread 10 on its outer wall. A limiter 2 and a counterweight sleeve 5 are fitted onto the central tie rod 4. A pawl 6 is engaged with the counterweight sleeve 5. A pawl fixing ring 7 is fitted onto the outer wall of the pawl 6. A hard alloy block unit is fixed to the pawl 6. The limiter 2, counterweight sleeve 5, pawl 6, and hard alloy block unit are connected along the direction from the lower connecting thread 1 to the upper connecting thread 10. The following are arranged sequentially: a number of pin holes 9 are provided on the central tie rod 4, and the limiter 2 is fixed to the central tie rod 4 through pins 3 in the pin holes 9 respectively; the central tie rod 4 includes a first straight section rod body 401, a lower connecting thread 1 is provided at one end of the first straight section rod body 401, and a gradually expanding section rod body 402 and a second straight section rod body 403 are sequentially fixed to the other end of the first straight section rod body 401, and an upper connecting thread 10 is provided at the other end of the second straight section rod body 403.

[0019] Example 5 The oil casing inner wall processing tool proposed in this embodiment is a file-like tool, such as... Figure 1 As shown, the device includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end has an upper connecting thread 10 on its outer wall. A limiter 2 and a counterweight sleeve 5 are fitted onto the central tie rod 4. A pawl 6 is engaged with the counterweight sleeve 5. A pawl fixing ring 7 is fitted onto the outer wall of the pawl 6. A hard alloy block unit is fixed to the pawl 6. The limiter 2, counterweight sleeve 5, pawl 6, and hard alloy block unit are arranged sequentially along the direction from the lower connecting thread 1 to the upper connecting thread 10. The central tie rod 4 has several pin holes 9, and the limiter 2 passes through several pin holes 9 with pins respectively. 3. Fixed to the central tie rod 4; the central tie rod 4 includes a first straight section rod 401, with a lower connecting thread 1 at one end of the first straight section rod 401, and a gradually expanding section rod 402 and a second straight section rod 403 sequentially fixed to the other end of the first straight section rod 401, with an upper connecting thread 10 at the other end of the second straight section rod 403; the limiter 2 and the counterweight sleeve 5 are both located on the outer wall of the first straight section rod 401, one end of the claw 6 is engaged with the counterweight sleeve 5 on the outer wall of the first straight section rod 401, and the other end of the claw 6 is fixed to the hard alloy block unit on the outer wall of the gradually expanding section rod 402. Example 6 The oil casing inner wall processing tool proposed in this embodiment is a file-like tool, such as... Figure 1 As shown, the device includes a central tie rod 4. One end of the central tie rod 4 has a lower connecting thread 1 on its outer wall, and the other end has an upper connecting thread 10 on its outer wall. A limiter 2 and a counterweight sleeve 5 are fitted onto the central tie rod 4. A pawl 6 is engaged with the counterweight sleeve 5. A pawl fixing ring 7 is fitted onto the outer wall of the pawl 6. A hard alloy block unit is fixedly connected to the pawl 6. The limiter 2, counterweight sleeve 5, pawl 6, and hard alloy block unit are arranged sequentially along the direction from the lower connecting thread 1 to the upper connecting thread 10. The central tie rod 4 has several pin holes 9. The limiter 2 is fixedly connected to the central tie rod 4 through pins 3 in the pin holes 9. The central tie rod 4 includes a first straight section rod body 401. The lower connecting thread 1 is provided on the first straight section rod body 401. One end of the straight section rod 401 and the other end of the first straight section rod 401 are sequentially fixed to the expanding section rod 402 and the second straight section rod 403. The upper connecting thread 10 is provided at the other end of the second straight section rod 403. The limiter 2 and the counterweight sleeve 5 are both provided on the outer wall of the first straight section rod 401. One end of the claw 6 is engaged with the counterweight sleeve 5 on the outer wall of the first straight section rod 401, and the other end of the claw 6 is fixed to the carbide block unit on the outer wall of the expanding section rod 402. The carbide block unit includes several carbide blocks 8, which are fixed to the outer wall of the claw 6 along the circumferential direction. The carbide blocks 8 and the claw 6 are fixed by either embedding or welding.

Claims

1. A file-like machining tool for the inner wall of an oil casing, characterized in that, Includes a central tie rod (4), one end of which has a lower connecting thread (1) on its outer wall and the other end of which has an upper connecting thread (10) on its outer wall. A limiter (2) and a counterweight sleeve (5) are fitted on the central tie rod (4). The counterweight sleeve (5) is engaged with a claw (6). A claw fixing ring (7) is fitted on the outer wall of the claw (6). A hard alloy block unit is fixed on the claw (6). The limiter (2), counterweight sleeve (5), chuck (6) and carbide block unit are arranged sequentially along the direction from the lower connecting thread (1) to the upper connecting thread (10); The central tie rod (4) has several pin holes (9), and the limiter (2) is fixed to the central tie rod (4) in the several pin holes (9) by pins (3); The central tie rod (4) includes a first straight section rod body (401), the lower connecting thread (1) is provided at one end of the first straight section rod body (401), the other end of the first straight section rod body (401) is sequentially fixed with a gradually expanding section rod body (402) and a second straight section rod body (403), and the upper connecting thread (10) is provided at the other end of the second straight section rod body (403); The limiter (2) and the counterweight sleeve (5) are both located on the outer wall of the first straight section rod (401). One end of the claw (6) is engaged with the counterweight sleeve (5) on the outer wall of the first straight section rod (401), and the other end of the claw (6) is fixed to the hard alloy block unit on the outer wall of the gradually expanding section rod (402).

2. The file-like machining tool for the inner wall of the oil casing according to claim 1, characterized in that, The cemented carbide block unit includes several cemented carbide blocks (8), and the several cemented carbide blocks (8) are fixed to the outer wall of the claw (6) along the circumferential direction.

3. The file-like machining tool for the inner wall of the oil casing according to claim 1, characterized in that, The cemented carbide blocks (8) and the claws (6) are all fixed by either inlay or welding.

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