Thin-wall short fish top annular slip fisher capable of being sleeved and milled
By designing a thin-walled annular slip and milled tooth structure, a milling-coated thin-walled short fish-top annular slip fishing device was developed, which solved the problem of stuck points in complex fishing environments in oil wells, improved the success rate and efficiency of fishing, and reduced the difficulty of operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-02
- Publication Date
- 2026-03-10
AI Technical Summary
During the downhole retrieval process in oil wells, retrieval often fails when the distance between the fish top and the stuck point is close, the length of the fish top above the coupling is short, the size of the fish top is large and the annular space is small, or the tubing string is severely stuck. In addition, the reverse-clamping operation has high requirements, resulting in a low success rate.
A milling-fitting annular slip for catching short fish with thin walls is designed. The annular slip with a thin wall structure is combined with a conical surface. The top of the fish is trimmed using a milling tooth structure. Torque transmission is achieved through a torque transmission key and a guide shoe keyway structure to ensure a stable connection between the slip and the fish. This design is suitable for complex catching environments.
It improved the success rate of salvage, reduced the need to repair the ring slip, increased salvage efficiency, reduced operational difficulty, and enhanced the reliability of the inverted lock.
Smart Images
Figure CN121630264A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of oil well fishing technology, specifically to a fishing tool with millable thin-walled short fish-top annular slips. Background Technology
[0002] Accidents involving tubing and tools falling into oil and gas wells are becoming increasingly common. During the retrieval process, situations often arise where the top of the fishing rod is very close to the point of blockage, or the length of the top of the fishing rod above the coupling is very short, the size of the top of the fishing rod is large but the annular space is small, the tubing is severely stuck, or the top of the fishing rod is deformed and damaged and needs to be repaired before retrieval can proceed. These issues frequently lead to "retrieval failures" in the retrieval work.
[0003] The inverted clamping method involves placing the inverted pipe or rod at the neutral point under the upward pulling force. This places the pipe or rod in a state of neither tension nor compression. Then, a reverse torque is applied to the unclamped pipe string. This torque acts on the inverted pipe string coupling through the unclamped pipe string, causing the unclamped pipe rod to disengage from the stuck pipe string. The inverted clamping method is then lifted to retrieve the pipe string. The key to the inverted clamping method is accurately locating the neutral point; this is crucial for success. This operation often requires experienced operators, and even experienced operators may experience "retrieval failures," especially in situations where the fish's top is very close to the jamming point, the fish's top is short above the coupling, the fish's top is large with a small annular gap, or the dropping pipe string is severely jammed. Therefore, this invention provides a milling-thin-walled short fish-top annular clamp retrieval device to ensure a high success rate in retrieval. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a millable, millable, thin-walled, short fish-top annular slip retrieval device. This solves the problems of frequent "retrieval failures" when the fish top is very close to the jamming point, or when the length of the fish top above the coupling is very small, the fish top size is large and the annular space is small, or when the dropping string encounters severe jamming; the fish top is deformed or damaged and needs to be repaired before retrieval; and the inverted operation has high requirements and also frequently results in "retrieval failures".
[0005] To achieve the above objectives, the present invention provides the following technical solution: a milling-fitting, thin-walled, short fish-top annular slip fishing device, comprising: The upper connector is fixedly installed at its top end with the retrieval tubing. The housing guide shoe is fixedly installed to the bottom of the upper connector. The bottom of the housing guide shoe is equipped with several annularly distributed milled tooth structures. The inner side of the housing guide shoe and near the bottom end is provided with a guide shoe inner cone surface. The side of the housing guide shoe is provided with a guide shoe keyway. The annular clamp has a wall thickness of 5-8 mm. Several annularly distributed alloy teeth are fixedly connected to the inner side of the annular clamp. The top of the annular clamp has clamp gaps and clamp through grooves. The number of clamp gaps is one less than the number of alloy teeth. The clamp gaps and clamp through grooves correspond one-to-one with the positions of the alloy teeth. The outer side of the annular clamp has an outer conical surface that is parallel to the inner conical surface of the guide shoe and has a diameter smaller than the inner conical surface of the guide shoe. A torque transmission key is fixedly connected to the side of the annular clamp and inside the keyway of the guide shoe. Two guide shoe keyways and two torque transmission keys are provided. The openings of the two guide shoe keyways are located on the same straight line, and the two guide shoe keyways are symmetrical about the axial section of the annular collet through the collet through the collet slot. The height of the guide shoe keyway is greater than the height of the torque transmission key, the width of the guide shoe keyway is greater than the width of the torque transmission key, and the side contact surface of the torque transmission key and the guide shoe keyway is the inner side of the guide shoe keyway away from the slip groove.
[0006] Preferably, the upper connector includes a body, a connector portion is fixedly connected to the top of the body, a female connector buckle is provided on the inner side of the connector portion, an outer guide slope is provided at the connection between the body and the connector portion, a male connector buckle is provided on the outer side of the body near the bottom, an inner guide slope is provided on the inner side of the body near the bottom, and a water eye is provided on the inner side of the body.
[0007] Preferably, the body and the connector are an integral structure.
[0008] Preferably, the shell guide shoe includes a cylindrical body, and the inner side of the cylindrical body is provided with a guide shoe inner conical surface and a guide shoe female buckle, the guide shoe female buckle being located above the guide shoe inner conical surface.
[0009] Preferably, the milling gear structure includes an installation port at the bottom end of the cylinder, and alloy milling gears are fixedly connected inside the installation port.
[0010] Preferably, the annular latch includes an annular body, the alloy teeth are provided in six sets, the latch gaps are provided in five, the latch groove cuts the annular body into an arc shape, and the five latch gaps divide the top of the arc-shaped annular body into six sections. The outer side of the annular body is provided with a first arc-shaped groove and a second arc-shaped groove. The first arc-shaped groove is located above the second arc-shaped groove. The first arc-shaped groove is connected to the first section, the second section, the third section, and the fourth section in a counterclockwise direction starting from the slot. The inner side of the first arc-shaped groove is provided with a first arc-shaped key. The first arc-shaped key and each section corresponding to the first arc-shaped groove are fixedly connected by a first connecting pin. The second arc-shaped groove is connected to the first section, the second section, the third section, and the fourth section in a clockwise direction starting from the slot. The inner side of the second arc-shaped groove is provided with a second arc-shaped key. The second arc-shaped key and each section corresponding to the second arc-shaped groove are fixedly connected by a second connecting pin.
[0011] Preferably, the alloy teeth are reversed teeth.
[0012] Preferably, a slip circulation groove is provided on the inner side of the annular slip and between two adjacent alloy teeth.
[0013] Preferably, the torque transmission key includes a first torque transmission key and a second torque transmission key.
[0014] This invention provides a milling-fitting, thin-walled, short fish top annular slip for retrieval. It has the following beneficial effects: 1. This invention, through the design of a thin-walled annular slip with a conical surface, allows the outer conical surface of the slip to press against the inner conical surface of the guide shoe during the lifting of the retrieval string. This causes the annular slip to deform, and the alloy teeth tightly clamp the fish head. This structural design results in a shorter clamping section of the annular slip, making it suitable for applications where the distance between the fish top and the jamming point is very short, the length of the fish top above the coupling is very small, the fish top is large with a small annular space clearance, and the retrieval string encounters severe jamming. A torque transmission key is fixedly connected to the side of the annular slip, and a guide shoe keyway is provided on the housing guide shoe. The height of the guide shoe keyway is designed to be greater than the height of the torque transmission key, and the width of the guide shoe keyway is... The width is greater than that of the torque transmission key, allowing the guide shoe keyway to slide up and down relative to the guide shoe without affecting the relative sliding of the annular slip and the guide shoe in the shell during the clamping process. At the same time, the structure of the guide shoe keyway and the torque transmission key can transmit the torsional torque to the annular slip, thereby implementing the inverted clamping. The side pressing contact surface between the torque transmission key and the guide shoe keyway is the inner side of the guide shoe keyway away from the slip through groove. During the inverted clamping process (when rotating), one side of the annular slip is subjected to greater force, which will further lock the annular slip, making its connection with the fish more stable. Compared with the traditional inverted clamping method, its retrieval success rate is higher.
[0015] 2. This invention, by designing a milling tooth structure at the bottom of the shell guide shoe, can easily trim the top of the fallen fish to facilitate retrieval. Compared with traditional trimming and retrieval, it only requires one well entry, making the retrieval efficiency much higher. Attached Figure Description
[0016] Figure 1 This is a perspective view of a millable, millable, thin-walled, short fish-top annular slip fishing device proposed in this invention; Figure 2 This is a front view of a millable, millable, thin-walled, short fish-top annular slip fishing device proposed in this invention; Figure 3 for Figure 2 Cross-sectional view of section line AA in the middle; Figure 4 for Figure 3 Enlarged view of a portion at point C; Figure 5 for Figure 2 Cross-sectional view of the section line at point BB; Figure 6 This is a first-view perspective perspective view of the upper connector of a millable, millable, thin-walled, short fish-top annular slip fishing device proposed in this invention. Figure 7 This is a second-view perspective perspective view of the upper connector of a millable, millable, thin-walled, short fish-top annular slip fishing device proposed in this invention. Figure 8 This is a perspective view of the shell guide shoe of a milling-thin-walled short fish-top annular slip retrieval device proposed in this invention; Figure 9 This is a first-view perspective perspective view of the annular slip of a millable, thin-walled, short fish-top annular slip fishing device proposed in this invention. Figure 10 This is a second-view perspective perspective view of the annular slip of a milled thin-walled short fish top annular slip fishing device proposed in this invention.
[0017] Among them, 1. Upper connector; 11. Body; 12. Connector part; 13. Male connector buckle; 14. Inner guide bevel; 15. Water eye; 16. Outer guide bevel; 17. Female connector buckle; 2. Shell guide shoe; 21. Cylinder; 22. Guide shoe female buckle; 23. Guide shoe inner conical surface; 24. Mounting port; 25. Alloy milled tooth; 26. Guide shoe keyway; 3. Annular slip; 31. Annular body; 32. Slip outer conical surface; 33. First torque transmission key; 34. Alloy tooth; 35. Slip gap; 36. Slip through groove; 37. Second torque transmission key; 38. First arc groove; 39. First arc key; 310. First connecting pin; 311. Second arc groove; 312. Second arc key; 313. Second connecting pin. Detailed Implementation
[0018] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0019] Example 1: like Figures 1-10 As shown, an embodiment of the present invention provides a milling-thin-walled short fish top annular slip catcher, including an upper connector 1, a shell guide shoe 2, and an annular slip 3.
[0020] The top of the upper connector 1 is fixedly installed with the fishing string, and the housing guide shoe 2 is fixedly installed with the bottom of the upper connector 1. The fishing string is used to transmit the rotation and pulling of the well tools, thereby driving the upper connector 1 and the housing guide shoe 2 to make corresponding movements.
[0021] The bottom of the shell guide shoe 2 is equipped with several annularly distributed milling tooth structures. These milling tooth structures can be configured in 16 groups. Using a drill string to drive the retrieval string to rotate, the upper connector 1 and the shell guide shoe 2 rotate, allowing the milling tooth structures to trim the top of the fallen fish for subsequent retrieval work. An inner conical surface 23 is provided on the inner side of the shell guide shoe 2 near its bottom, and a keyway 26 is provided on the side of the shell guide shoe 2. The annular slip 3 has a wall thickness of 5-8 mm. During retrieval, the annular slip 3 is tightly pressed against the inner side of the inner conical surface 23 of the guide shoe, so even with its thin wall structure, it can provide a large retrieval force. Several annularly distributed... The alloy teeth 34 are reversed teeth and made of YD alloy, which can provide good biting force. The top of the annular slip 3 has slip gaps 35 and slip grooves 36. The design of slip gaps 35 and slip grooves 36 is to facilitate deformation of the annular slip 3. The number of slip gaps 35 is one less than the number of alloy teeth 34. The positions of slip gaps 35 and slip grooves 36 correspond one-to-one with the positions of alloy teeth 34. The outer side of the annular slip 3 has a slip outer cone surface 32 that is parallel to the inner cone surface 23 of the guide shoe and has a smaller diameter than the inner cone surface 23 of the guide shoe. A torque transmission key is fixedly connected to the side of the annular slip 3 and inside the guide shoe keyway 26.
[0022] There are two guide shoe keyways 26 and two torque transmission keys. The openings of the two guide shoe keyways 26 are located on the same straight line. The two guide shoe keyways 26 are symmetrical about the axial section of the annular slip 3 passing through the slip groove 36. The two guide shoe keyways 26 are used in conjunction with the two torque transmission keys to ensure the stability of the relative vertical movement of the housing guide shoe 2 and the annular slip 3, and to better transmit torque.
[0023] The height of the guide shoe keyway 26 is greater than the height of the torque transmission key, so that the torque transmission key located inside the guide shoe keyway 26 can slide freely up and down. The width of the guide shoe keyway 26 is greater than the width of the torque transmission key, and the side contact surface of the torque transmission key and the guide shoe keyway 26 is the inner side of the guide shoe keyway 26 away from the slip groove 36.
[0024] During the retrieval process, the rotation of the drill string is transmitted through the retrieval string, driving the upper connector 1 and the shell guide shoe 2 to rotate. The rotating milling gear structure trims the top of the fish. Then, the upper connector 1 and the shell guide shoe 2 are further controlled to move downward. Under the guidance of the bottom port of the shell guide shoe 2, the top of the fallen fish is inserted into the inner side of the annular slip 3, pushing the annular slip 3 to move upward relative to the shell guide shoe 2 a certain distance. At this time, the retrieval string can be lifted, and the upper connector 1 and the shell guide shoe 2 will move directly upward. The annular slip 3 will rub against the fallen fish and move downward relative to the shell guide shoe 2. As the lifting force increases, the relative movement of the annular slip 3 and the shell guide shoe 2 increases. The inner conical surface 23 of the guide shoe squeezes the outer conical surface 32 of the slip, causing the annular slip 3 to deform (narrow its diameter), so that the annular slip 3 firmly grasps the fallen fish.
[0025] When applying the inverted clamp, it is necessary to ensure that the lifting force of the fishing string on the fish is kept within a small range. If the lifting force is too large, the threaded connection at the coupling of the fishing string will be too tight and difficult to disassemble. It is necessary to strictly control the position to be at the neutral point. At this time, it is difficult to guarantee the gripping force between the annular clamp 3 and the fish (the gripping force between the annular clamp 3 and the fish increases with the increase of the lifting force). In this structure design, when the upper connector 1 and the housing guide shoe 2 are driven to rotate, the rotation is transmitted by the side compression contact surface of the torque transmission key and the guide shoe keyway 26. The force is directly applied to one side of the annular clamp 3 to rotate, and the other side follows the rotation. The annular clamp 3 will also deform (reduction in diameter) during this process, so that the annular clamp 3 firmly grasps the fish and ensures the success rate of the inverted clamp.
[0026] In one embodiment, the upper connector 1 includes a body 11, a connector portion 12 is fixedly connected to the top of the body 11, a connector female buckle 17 is provided on the inner side of the connector portion 12, the connector female buckle 17 is threadedly connected to the retrieval string, an outer guide slope 16 is provided at the connection between the body 11 and the connector portion 12, a connector male buckle 13 is provided on the outer side of the body 11 near the bottom, the connector male buckle 13 is used to connect the housing guide shoe 2, an inner guide slope 14 is provided on the inner side of the body 11 near the bottom, and a water eye 15 is provided on the inner side of the body 11, the water eye 15 is used for normal water supply during circulating well washing.
[0027] In one embodiment, the body 11 and the connector 12 are an integral structure to ensure the stability of the structure.
[0028] In one embodiment, the housing guide shoe 2 includes a cylindrical body 21. The inner side of the cylindrical body 21 is provided with a guide shoe inner conical surface 23 and a guide shoe female buckle 22. The guide shoe female buckle 22 is located above the guide shoe inner conical surface 23. The guide shoe inner conical surface 23 corresponds to the outer conical surface 32 of the slip. The guide shoe female buckle 22 is used to connect the connector male buckle 13.
[0029] In one embodiment, the milling structure includes an installation port 24 at the bottom of the cylinder 21, and an alloy milling gear 25 is fixedly connected inside the installation port 24, so that the alloy milling gear 25 can be disassembled and replaced for long-term use.
[0030] In one embodiment, the annular slip 3 includes an annular body 31, six sets of alloy teeth 34, five slip gaps 35, and a slip through groove 36 that cuts the annular body 31 into an arc shape. The five slip gaps 35 divide the top of the arc-shaped annular body 31 into six sections.
[0031] The outer side of the annular body 31 is provided with a first arc-shaped groove 38 and a second arc-shaped groove 311. The first arc-shaped groove 38 is located above the second arc-shaped groove 311. The first arc-shaped groove 38 is connected to the first section, the second section, the third section, and the fourth section, starting from the slip groove 36 and counting in a counterclockwise direction. The inner side of the first arc-shaped groove 38 is provided with a first arc-shaped key 39. The first arc-shaped key 39 and each section corresponding to the first arc-shaped groove 38 are fixedly connected by a first connecting nail 310. That is, there are also four first connecting nails 310, which correspond to the first section, the second section, the third section, and the fourth section, respectively, starting from the slip groove 36 and counting in a counterclockwise direction.
[0032] The second arc-shaped groove 311 extends from the slot 36, clockwise, to the first, second, third, and fourth sections. A second arc-shaped key 312 is provided on the inner side of the second arc-shaped groove 311. The second arc-shaped key 312 and each section corresponding to the second arc-shaped groove 311 are fixedly connected by a second connecting pin 313.
[0033] Among them, the third and fourth sections, counting clockwise from the 36th slot of the kava, correspond to the fourth and third sections, counting clockwise from the 36th slot of the kava.
[0034] like Figure 5 As shown, the torque transmission keys include a first torque transmission key 33 and a second torque transmission key 37, which are symmetrically distributed on both sides of the slip groove 36. If the housing guide shoe 2 rotates clockwise, the contact part corresponding to the first torque transmission key 33 drives the annular slip 3 to rotate. If it rotates counterclockwise, the contact part corresponding to the second torque transmission key 37 drives the annular slip 3 to rotate. The rotation in both directions causes the annular slip 3 to deform during the rotation, thereby increasing the clamping force with the fish and ensuring the success rate of the inverted lock.
[0035] In one embodiment, a slip circulation groove is provided on the inner side of the annular slip 3 and between two adjacent alloy teeth 34, so that the alloy teeth 34 are in an inwardly protruding state, so that they can be well clamped on the fish.
[0036] Although embodiments of the 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 invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A thin-walled short fish-top ring-shaped slip bowl fisher with a casing, comprising an upper joint (1), the top end of the upper joint (1) is fixedly installed with a fishing string, characterized in that, Also include: The shell guide shoe (2) is fixedly installed at the bottom of the upper joint (1), the bottom of the shell guide shoe (2) is provided with a plurality of annular milling tooth structures, the inner side of the shell guide shoe (2) is provided with a guide shoe inner taper surface (23) close to the bottom end, and the side of the shell guide shoe (2) is provided with a guide shoe key groove (26). The wall thickness of the ring-shaped slip (3) is 5-8MM, the inner side of the ring-shaped slip (3) is fixedly connected with a plurality of annular alloy teeth (34), the top end of the ring-shaped slip (3) is provided with a slip gap (35) and a slip through slot (36), the number of the slip gap (35) is less than that of the alloy tooth (34) by one, the slip gap (35) and the slip through slot (36) correspond to the position of the alloy tooth (34) one by one, the outer side of the ring-shaped slip (3) is provided with a slip outer taper surface (32) which is parallel to the guide shoe inner taper surface (23) and has a diameter smaller than that of the guide shoe inner taper surface (23), and the side of the ring-shaped slip (3) and inside the guide shoe key groove (26) is fixedly connected with a torque transmission key. The guide shoe key groove (26) and the torque transmission key are provided with two, the through openings of the two guide shoe key grooves (26) are located on the same straight line, and the two guide shoe key grooves (26) are symmetrical about the axial section of the ring-shaped slip (3) passing through the slip through slot (36). The height of the guide shoe key groove (26) is greater than that of the torque transmission key, the width of the guide shoe key groove (26) is greater than that of the torque transmission key, and the side pressing contact surface of the torque transmission key and the guide shoe key groove (26) is the inner side of the guide shoe key groove (26) away from the slip through slot (36).
2. A fish neck ring shaped slip bowl according to claim 1, wherein: The upper joint (1) comprises a body (11), the top end of the body (11) is fixedly connected with a joint part (12), the inner side of the joint part (12) is provided with a joint female buckle (17), the connection between the body (11) and the joint part (12) is provided with an outer guide slope (16), the outer side of the body (11) and close to the bottom end is provided with a joint male buckle (13), the inner side of the body (11) and close to the bottom end is provided with an inner guide slope (14), and the inner side of the body (11) is provided with a water eye (15).
3. A fish neck ring shaped slip bowl according to claim 2, wherein: The body (11) and the joint part (12) are an integral structure.
4. A fish-bond ring shaped slip bowl according to claim 1, wherein: The shell guide shoe (2) comprises a cylinder (21), the inner side of the cylinder (21) is provided with a guide shoe inner taper surface (23) and a guide shoe female buckle (22), and the guide shoe female buckle (22) is located above the guide shoe inner taper surface (23).
5. A milling-fitting thin-walled short fish-top annular slip fishing device according to claim 4, characterized in that: The milling tooth structure comprises an installation opening (24) provided at the bottom end of the cylinder (21), and the inner side of the installation opening (24) is fixedly connected with an alloy milling tooth (25).
6. A fishing tool according to claim 1, wherein: The ring-shaped slip (3) comprises a ring-shaped body (31), the alloy tooth (34) is provided with six groups, the slip gap (35) is provided with five, the slip through slot (36) cuts the ring-shaped body (31) into an arc shape, and the five slip gaps (35) separate the top of the arc-shaped ring-shaped body (31) into six sections. The outer side of the annular body (31) is provided with a first arc-shaped slot (38) and a second arc-shaped slot (311), the first arc-shaped slot (38) is located above the second arc-shaped slot (311), the first arc-shaped slot (38) starts from the slip-through slot (36), and the first arc-shaped slot (38) is sequentially provided with a first section, a second section, a third section and a fourth section in a counterclockwise direction, the inner side of the first arc-shaped slot (38) is provided with a first arc-shaped key (39), the first arc-shaped key (39) is fixedly connected with each section of the first arc-shaped slot (38) through a first connecting pin (310), the second arc-shaped slot (311) starts from the slip-through slot (36), and the second arc-shaped slot (311) is sequentially provided with a first section, a second section, a third section and a fourth section in a clockwise direction, the inner side of the second arc-shaped slot (311) is provided with a second arc-shaped key (312), and the second arc-shaped key (312) is fixedly connected with each section of the second arc-shaped slot (311) through a second connecting pin (313).
7. A milling-fitting, thin-walled, short fish-top annular slip fishing device according to claim 1, characterized in that: The alloy tooth (34) is a reverse tooth.
8. A milling-fitting thin-walled short fish-top annular slip fishing device according to claim 1, characterized in that: The inner side of the annular slip (3) and between the two adjacent alloy teeth (34) are provided with a slip circulation groove.
9. A milling-fitting, thin-walled, short fish-top annular slip fishing device according to claim 1, characterized in that: The torque transmission key comprises a first torque transmission key (33) and a second torque transmission key (37).