Steel wire recoverable type double-slip blanking plug for underground oil pipe

Abstract

The invention discloses a steel wire recoverable type double-slip blanking plug for an underground oil pipe, and relates to the technical field of slip blanking plugs. Which comprises a fishing neck, a locking slip, an outer barrel, a slip body, a rubber barrel and a balance valve, and is characterized in that the upper end of the fishing neck is connected with an external tripping-in tool, a mandrel body is arranged at the lower end of the fishing neck through fine threads, and the fishing neck and the mandrel body are locked and prevented from loosening through the fine threads and a positioning nut; the locking slip and the slip body are both attached to the conical surface of the mandrel body in a pre-clinging mode through buffer springs, and the outer side of the locking slip and the outer side of the slip body are both in sliding fit with the inner wall of the outer cylinder. Through the functions of separation, jarring, expansion and sealing of the tool string, stable and efficient operation of the tool in oil pipe operation is ensured, the anti-pressure capability and the sealing reliability are enhanced, and meanwhile, the operation effect and convenience of the tool are effectively improved through combination of vibration control and the two-way anchoring technology.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of slip packer, in particular to a downhole oil pipe steel wire recyclable double slip packer. BACKGROUND

[0002] The slip packer is a mechanical plugging tool used in oil and gas well operations, mainly used for temporary or permanent plugging of the internal passage of the oil pipe or casing to prevent fluid flow or blowout. Its core feature is to use "slips (anchoring mechanism) and sealing elements (such as rubber cylinders, rubber bowls)" to achieve bidirectional or unidirectional plugging, and to be put and recycled through tools such as steel wire and coiled tubing.

[0003] The existing slip packer has a single structure design, lacks effective bidirectional anchoring and support, and is prone to deformation or local damage in a high-pressure oil pipe environment, which cannot withstand complex loads and impact forces in the operation, resulting in insufficient pressure resistance. At the same time, the uneven force or unreasonable design of the sealing elements (such as rubber cylinders) in the slip packer can cause local stress concentration, resulting in material tearing or deformation. In addition, pressure fluctuations and temperature changes in the oil pipe can also cause the sealing material to degrade, leading to sealing failure. Moreover, there is a large mechanical vibration and impact during the oil pipe operation, and if there is no buffering and damping measures, the vibration force will be directly transmitted to the internal components, causing the connection to fatigue, shear pin to break or the assembly to loosen, thereby affecting the overall performance and service life of the tool. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a downhole oil pipe steel wire recyclable double slip packer, which solves the problems mentioned in the background.

[0005] To achieve the above purpose, the present application is realized by the following technical scheme: A downhole oil pipe steel wire recyclable double slip packer, comprising a fishing neck, a locking slip, an outer cylinder, a slip body, a rubber cylinder and a balance valve, characterized in that: the upper end of the fishing neck is connected with an external running tool, the lower end of the fishing neck is provided with a core shaft body through a fine thread, and the fishing neck and the core shaft body are locked and prevented from loosening through a fine thread and a positioning nut; The locking slip and the slip body are pre-tightened and attached to the conical surface of the core shaft body through a buffer spring, and the outer sides of the locking slip and the slip body are in sliding fit with the inner wall of the outer cylinder; The upper end of the outer cylinder is threadedly connected with a mounting body, the core shaft body is threadedly connected with a slip core shaft, the lower end of the outer cylinder is limited by the slip core shaft, and the positioning nut and the mounting body are provided with a copper shear pin; The rubber cylinder is sleeved in the middle part of the core shaft body, the balance valve is installed on the mounting body, and the balance valve is provided with a sliding sleeve; The auxiliary assembly is arranged on the balance valve.

[0006] Preferably, the core shaft body penetrates through the entire tool, the upper taper surface of the core shaft body matches with the inner taper of the locking slip, and the lower taper surface of the core shaft body matches with the inner taper of the slip body, forming a bidirectional anchoring structure.

[0007] Preferably, the rubber cylinder is provided with a positioning gauge ring and a positioning pad ring at both ends, the rubber cylinder is fixed with the core shaft body through the positioning gauge ring and the positioning pad ring, and the step structure on the inner wall of the mounting body compresses the rubber cylinder to realize sealing when the tool is pulled up.

[0008] Preferably, the auxiliary assembly comprises a connecting spring fixedly connected to the bottom of the balance valve, a mounting block fixedly connected to the end of the connecting spring away from the balance valve, a plurality of mounting grooves formed in the mounting block, a lower driving rod rotatably installed in the mounting groove, and a connecting groove formed in the end of the lower driving rod away from the mounting groove.

[0009] Preferably, the connecting groove is fixedly installed with a mounting shaft, the mounting shaft is rotatably installed with an upper driving rod, and the end of the upper driving rod away from the connecting groove is fixedly installed with a connecting frame.

[0010] Preferably, the connecting frame is fixedly installed at the bottom of the balance valve, the lower driving rod and the upper driving rod are arranged in an inclined manner, and the lower driving rod and the upper driving rod are arranged in a V-shaped manner.

[0011] Preferably, a plurality of Z-shaped guide pipes are fixedly installed on the balance valve, a driven pull rope is fixedly connected to the copper shear pin, the ends of the mounting shaft are fixedly installed with abutting rollers, the abutting rollers are fixedly installed with connecting frame plates, and U-shaped connecting frames are fixedly installed on the two connecting frame plates.

[0012] Preferably, the end of the driven pull rope away from the copper shear pin passes through the Z-shaped guide pipe and is fixedly connected to the U-shaped connecting frame, one end of the Z-shaped guide pipe is located outside the balance valve, and the other end of the Z-shaped guide pipe is located below the balance valve.

[0013] The application provides a downhole oil pipe steel wire recyclable double-grip plug. Compared with the prior art, the application has the following beneficial effects: 1. The present application, when the tool string is lowered, the rapid relative movement of the mandrel body and the outer cylinder pushes the locking slips and the upper support of the slip body apart, forms preliminary fixation by engaging the inner wall of the oil pipe through the sawtooth structure, the copper shear pin is cut off at this time, the tool string and the fishing neck are separated, the installation body is moved upward, the shear pin of the positioning nut is cut off, the installation body continues to push the slip body to expand, forming a two-way anchor, enhancing the compression resistance, the relative displacement of the mandrel body and the positioning gauge ring is generated by the static tension of the steel wire rope, the rubber cylinder expands radially, forming an elastic seal, the positioning washer is used to balance the stress of the rubber cylinder and prevent local tearing, the balance valve is opened automatically after setting, the pressure difference between the upper and lower sides of the balance valve is used to avoid seal failure, and the shock impact is completed by the sliding sleeve and the buffer spring during the setting process, protecting the internal components; 2. When the upward shock is generated, the vibration force is directly transmitted to the connecting spring, the connecting spring drives the installation block to move upward under the action of the connecting spring force, the lower driving rod is moved outward through the cooperation of the installation slot on the installation block and the lower driving rod, the cooperation of the lower driving rod and the upper driving rod through the installation shaft, and the cooperation of the upper driving rod and the connecting frame, so that the connecting place of the lower driving rod and the upper driving rod moves outward, and the matching roller on the installation shaft directly matches the inner wall of the oil pipe, the vibration force is converted into radial supporting force, and the effect of the tool in use is effectively improved; 3. When the matching roller on the installation shaft moves outward, the connecting frame plate on the matching roller drives the U-shaped connecting frame to move synchronously, the driven pull rope on the U-shaped connecting frame pulls the copper shear pin outward through the function of the Z-shaped guide pipe, so that the copper shear pin is cut more conveniently, and the two-way anchoring effect is also ensured; 4. The present application, through the functions of tool string separation, shock, expansion and sealing, ensures stable and efficient operation of the tool in the oil pipe operation, enhances the compression resistance and sealing reliability, and effectively improves the operation effect and convenience of the tool by combining the vibration control and two-way anchoring technology. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a schematic diagram of the overall structure of the present application; Figure 2 is a schematic diagram of the internal structure of the locking slip of the present application; Figure 3 is a schematic diagram of the internal structure of the balance valve of the present application; Figure 4 is a schematic diagram of the structure of the installation block of the present application; Figure 5 is a schematic diagram of the structure of the auxiliary component of the present application; Figure 6 is a schematic diagram of part of the structure of the balance valve of the present application; Figure 7 Fig. 2 is a schematic view of the auxiliary assembly in the present application; Figure 6 Fig. 3 is an enlarged view of the portion A in Fig. 2; Figure 8 Fig. 4 is a schematic view of the auxiliary assembly in the present application.

[0015] In the figure: 1, fishing neck; 2, locking slip; 3, positioning nut; 4, slip mandrel; 5, outer cylinder; 6, slip body; 7, mandrel body; 8, mounting body; 9, positioning gauge ring; 10, positioning spacer ring; 11, rubber cylinder; 12, balance valve; 13, sliding sleeve; 14, buffer spring; 15, copper shear pin; 16, connecting spring; 17, mounting block; 18, mounting groove; 19, lower driving rod; 20, connecting groove; 21, mounting shaft; 22, upper driving rod; 23, connecting frame; 24, Z-shaped guide pipe; 25, driven pull rope; 26, matching roller; 27, connecting frame plate; 28, U-shaped connecting frame. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0017] Please refer to Figures 1-8The application discloses a downhole oil pipe steel wire recyclable double-grip plug, which comprises a fishing neck 1, locking grips 2, an outer cylinder 5, a grip body 6, a rubber cylinder 11 and a balance valve 12, the upper end of the fishing neck 1 is connected with an external running tool, the lower end of the fishing neck 1 is provided with a core shaft body 7 through a fine thread, the fishing neck 1 and the core shaft body 7 are locked and prevented from loosening through the fine thread and a positioning nut 3, the locking grips 2 and the grip body 6 are pre-tightened and attached on the conical surface of the core shaft body 7 through buffer springs 14, the outer sides of the locking grips 2 and the grip body 6 are slidably matched with the inner wall of the outer cylinder 5, the upper end of the outer cylinder 5 is threadedly connected with a mounting body 8, the core shaft body 7 is threadedly connected with a grip core shaft 4, the lower end of the outer cylinder 5 is limited through the grip core shaft 4, the positioning nut 3 and the mounting body 8 are provided with copper shear pins 15, the rubber cylinder 11 is sleeved in the middle part of the core shaft body 7, the balance valve 12 is mounted on the mounting body 8, the balance valve 12 is provided with a sliding sleeve 13, the core shaft body 7 penetrates through the whole tool, the upper conical surface of the core shaft body 7 is matched with the inner cone of the locking grips 2, the lower conical surface of the core shaft body 7 is matched with the inner cone of the grip body 6, thereby forming a bidirectional anchoring structure, the rubber cylinder 11 is provided with positioning gauge rings 9 and positioning washer rings 10 at both ends, the rubber cylinder 11 is fixed with the core shaft body 7 through the positioning gauge rings 9 and the positioning washer rings 10, the step structure of the inner wall of the mounting body 8 compresses the rubber cylinder 11 to realize sealing when the tool is pulled up, wherein the step structure of the inner wall of the mounting body 8 and the conical surfaces on various structures are all known technologies in the field and will not be described in detail here.

[0018] In the embodiment, In use, when the tool string is lowered, the core shaft body 7 and the outer cylinder 5 are pushed to drive the locking grips 2 and the grip body 6 to be expanded upward through the sawtooth structure to be engaged with the inner wall of the oil pipe to be preliminarily fixed, at this time, the copper shear pins 15 are sheared to realize the separation of the tool string and the fishing neck 1, the mounting body 8 is moved upward to shear the shear pins of the positioning nut 3, then the mounting body 8 continues to drive the grip body 6 to be expanded downward to form a bidirectional anchoring structure to enhance the compression resistance, wherein the static tension of the steel wire rope drives the core shaft body 7 and the positioning gauge rings 9 to be relatively displaced to make the rubber cylinder 11 expand radially to form an elastic sealing, wherein the positioning washer rings 10 are used to balance the stress of the rubber cylinder 11 to prevent local tearing, the rubber cylinder 11 is automatically opened after setting, the pressure difference between the upper and lower sides of the rubber cylinder 11 is utilized to avoid sealing failure, and the sliding sleeve 13 and the buffer spring 14 are utilized to complete the buffer vibration impact in the setting process to protect the internal components.

[0019] The auxiliary assembly is arranged on the balance valve 12, and the auxiliary assembly comprises a connecting spring 16 fixedly connected to the bottom of the balance valve 12, a mounting block 17 fixedly connected to the end of the connecting spring 16 away from the balance valve 12, a plurality of mounting grooves 18 formed in the mounting block 17, a lower driving rod 19 rotatably arranged in the mounting groove 18, a connecting groove 20 formed in the end of the lower driving rod 19 away from the mounting groove 18, a mounting shaft 21 fixedly arranged in the connecting groove 20, an upper driving rod 22 rotatably arranged on the mounting shaft 21, a connecting frame 23 fixedly arranged on the end of the upper driving rod 22 away from the connecting groove 20, the connecting frame 23 being fixedly arranged on the bottom of the balance valve 12, the lower driving rod 19 and the upper driving rod 22 being arranged in an inclined manner, the lower driving rod 19 and the upper driving rod 22 being arranged in a V shape, a plurality of Z-shaped pipes 24 fixedly arranged on the balance valve 12, a driven pull rope 25 fixedly connected to the copper shear pin 15, a sticking roller 26 fixedly arranged on the two ends of the mounting shaft 21, a connecting frame plate 27 fixedly arranged on the sticking roller 26, a U-shaped connecting frame 28 fixedly arranged on the two connecting frame plates 27, the end of the driven pull rope 25 away from the copper shear pin 15 penetrating through the Z-shaped pipe 24 and being fixedly connected to the U-shaped connecting frame 28, one end of the Z-shaped pipe 24 being located outside the balance valve 12, the other end of the Z-shaped pipe 24 being located below the balance valve 12, wherein the sticking roller 26 is located outside the lower driving rod 19, and the position of the connecting frame plate 27 is located above the sticking roller 26, so that the U-shaped connecting frame 28 on the connecting frame plate 27 does not affect the normal movement of the lower driving rod 19 and the upper driving rod 22.

[0020] In the embodiment, when the tool is struck upward, the vibration force generated is directly transmitted to the connecting spring 16, the connecting spring 16 drives the mounting block 17 to move upward under the action of the force of the connecting spring 16 when the tool is struck upward, the mounting groove 18 on the mounting block 17 cooperates with the lower driving rod 19, the lower driving rod 19 cooperates with the upper driving rod 22 through the mounting shaft 21, and the upper driving rod 22 cooperates with the connecting frame 23, so that the connection between the lower driving rod 19 and the upper driving rod 22 moves outward, the sticking roller 26 on the mounting shaft 21 directly sticks to the inner wall of the oil pipe, the vibration force is converted into a radial supporting force, the effect of the tool in use is effectively improved, when the sticking roller 26 on the mounting shaft 21 moves outward, the connecting frame plate 27 on the sticking roller 26 drives the U-shaped connecting frame 28 to move synchronously, the driven pull rope 25 on the U-shaped connecting frame 28 pulls the copper shear pin 15 outward through the function of the Z-shaped pipe 24, so that the copper shear pin 15 is more convenient to cut, and the bidirectional anchoring effect is ensured.

[0021] Working principle: The entire tool is divided into three stages: 1. The working principle of the setting mechanism: when the tool string is lowered, the rapid relative movement of the mandrel body 7 and the outer cylinder 5 pushes the locking slips 2 and the upper support of the slip body 6 apart, forming a preliminary fixation by engaging the inner wall of the oil pipe through the sawtooth structure, at this time the copper shear pin 15 is cut off, realizing the separation of the tool string and the fishing neck 1, upward jarring makes the installation body 8 move up, after cutting the shear pin of the positioning nut 3, the installation body 8 continues to push the lower expansion of the slip body 6, forming a double-direction anchoring, enhancing the compression resistance; 2. The principle of the sealing system: the relative displacement of the mandrel body 7 and the positioning ring 9 driven by the static tension of the steel wire rope makes the rubber cylinder 11 expand radially, forming an elastic seal, the positioning washer 10 is used to balance the stress of the rubber cylinder 11 to prevent local tearing, and the setting is automatically opened, using the pressure difference between the upper and lower sides of the balance rubber cylinder 11 to avoid seal failure; 3. Safety release mechanism: during the setting process, the buffer spring 14 and the sliding sleeve 13 are used to complete the buffer vibration impact, protecting the internal components, when continuing to jar upward, the steel shear pin 15 on the running-in tool is cut off, and the tool string can be lifted; When jarring upward, the vibration force is directly transmitted to the connecting spring 16, the connecting spring 16 is displaced upward by the force of the connecting spring 16 when jarring upward, the installation groove 18 on the installation block 17 cooperates with the lower drive rod 19, the lower drive rod 19 cooperates with the upper drive rod 22 through the installation shaft 21, and the upper drive rod 22 cooperates with the connecting frame 23, so that the connection between the lower drive rod 19 and the upper drive rod 22 moves outward, the matching roller 26 on the installation shaft 21 directly matches the inner wall of the oil pipe, the vibration force is converted into radial support force, effectively improving the efficiency of the tool in use, when the matching roller 26 on the installation shaft 21 moves outward, the connecting frame plate 27 on the matching roller 26 moves synchronously, the driven pull rope 25 on the U-shaped connecting frame 28 moves outward through the function of the Z-shaped guide pipe 24, completing the outward pulling of the copper shear pin 15, ensuring that the copper shear pin 15 is cut more conveniently, and also ensuring the effect of double-direction anchoring.

[0022] In the technical solution, the installation principle of the plugger (without auxiliary components) is as follows: The locking slip 2 is installed in the slip mandrel 4, the fishing neck 1 is tightened, the positioning nut 3 is sleeved on the slip mandrel 4 and the installation body 8, the slip body 6 is installed in the groove of the outer cylinder 5, the above-mentioned installed parts are placed on both sides of the outer cylinder 5, the positioning nut 3 is tightened, the mandrel body 7 is clamped on the vice, the positioning ring 9, the positioning washer 10, the rubber cylinder 11, the balance valve 12, the spring and the like are sequentially installed, the installation body 8 is clamped on the vice, the mandrel body 7 is installed, and the rubber cylinder 11 positioning ring 9 is tightened; The disassembly principle of the plugger (without auxiliary components) is as follows: The clamp is clamped on the vice, the rubber sleeve 11 positioning gauge ring 9 is unscrewed, the mandrel body 7 is taken out, the mandrel body 7 is clamped on the vice, the balance valve 12, the positioning washer ring 10, the rubber sleeve 11 and the positioning gauge ring 9 are taken off in sequence, the outer cylinder 5 is clamped on the vice, the positioning nut 3 at both ends of the outer cylinder 5 is unscrewed, the slip mandrel 4 and the installation body 8 are taken out from both ends of the outer cylinder 5; The slip body 6 is poured out from the outer cylinder 5, the slip mandrel 4 is clamped on the vice, the fishing neck 1 is unscrewed, the locking slip 2 is taken out from the slip mandrel 4, the parts are cleaned, and the sealing element is checked.

[0023] It should be noted that, in the present document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0024] While embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, alternatives, and variations can be made in the embodiments without departing from the spirit and scope of the present application.

Claims

1. A downhole tubing wire retrievable double slip packer, comprising a fishing neck (1), a locking slip (2), an outer cylinder (5), a slip body (6), a rubber cylinder (11) and a balance valve (12), characterized in that: The upper end of the fishing neck (1) is connected with an external running tool, the lower end of the fishing neck (1) is provided with a core shaft body (7) through a fine thread, the fishing neck (1) and the core shaft body (7) are locked and prevented from loosening through a fine thread and a positioning nut (3); The locking slips (2) and the slip bodies (6) are pre-tightly attached to the conical surface of the core shaft body (7) through buffer springs (14), and the outer sides of the locking slips (2) and the slip bodies (6) are in sliding fit with the inner wall of the outer cylinder (5); The upper end of the outer cylinder (5) is threadedly connected with a mounting body (8), the core shaft body (7) is threadedly connected with a slip core shaft (4), the lower end of the outer cylinder (5) is limited through the slip core shaft (4), and the positioning nut (3) and the mounting body (8) are provided with copper shear pins (15). The rubber cylinder (11) is sleeved in the middle part of the core shaft body (7), the balance valve (12) is mounted on the mounting body (8), and the balance valve (12) is provided with a sliding sleeve (13). The balance valve (12) is provided with an auxiliary assembly.

2. A wireline retrievable double- slip packer for use in oil country tubular goods according to claim 1, characterized in that: The core shaft body (7) penetrates through the whole tool, the upper conical surface of the core shaft body (7) is in fit with the inner conical surface of the locking slip (2), and the lower conical surface of the core shaft body (7) is in fit with the inner conical surface of the slip body (6), so that a bidirectional anchoring structure is formed.

3. A wire retrievable double slip plug for use in oil country tubular goods according to claim 1, characterized in that: The rubber cylinder (11) is provided with positioning gauge rings (9) and positioning spacer rings (10) at both ends, the rubber cylinder (11) is fixed with the core shaft body (7) through the positioning gauge rings (9) and the positioning spacer rings (10), and the stepped structure of the inner wall of the mounting body (8) compresses the rubber cylinder (11) to realize sealing when the tool is pulled up.

4. A wireline retrievable double- slip packer for use in oil country tubular goods according to claim 1, characterized in that: The auxiliary assembly comprises a connecting spring (16) fixedly connected to the bottom of the balance valve (12), an installation block (17) fixedly connected to the end, away from the balance valve (12), of the connecting spring (16), a plurality of installation grooves (18) formed in the installation block (17), a lower driving rod (19) rotatably installed in the installation groove (18), and a connecting groove (20) formed in the end, away from the installation groove (18), of the lower driving rod (19).

5. A wire retrievable double slip packer for use in oil country tubular goods according to claim 4, characterized in that: An installation shaft (21) is fixedly installed in the connecting groove (20), an upper driving rod (22) is rotatably installed on the installation shaft (21), and a connecting frame (23) is fixedly installed on the end, away from the connecting groove (20), of the upper driving rod (22).

6. A wire retrievable double slip plug for use in oil country tubular goods according to claim 5, characterized in that: The connecting frame (23) is fixedly installed at the bottom of the balance valve (12), the lower driving rod (19) and the upper driving rod (22) are both arranged in an inclined manner, and the lower driving rod (19) and the upper driving rod (22) are arranged in a V shape.

7. A wire retrievable double slip plug for use in oil country tubular goods according to claim 5, characterized in that: A plurality of Z-shaped guide pipes (24) are fixedly installed on the balance valve (12), a driven pull rope (25) is fixedly connected to the copper shear pin (15), the both ends of the installation shaft (21) are fixedly installed with abutting rollers (26), the abutting rollers (26) are fixedly installed with connecting frame plates (27), and U-shaped connecting frames (28) are fixedly installed on the two connecting frame plates (27).

8. A wire retrievable double slip packer for use in oil country tubular goods according to claim 7, characterized in that: The driven pull rope (25) passes through the Z-shaped conduit (24) from the end of the copper shear pin (15) away, and is fixedly connected to the U-shaped connecting frame (28), one end of the Z-shaped conduit (24) is outside the balance valve (12), and the other end of the Z-shaped conduit (24) is below the balance valve (12).

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