Extrusion rubber sleeve single slip bridge plug

Abstract

The utility model relates to oil and gas well packer tool technical field, concretely is a kind of extruded rubber tube single slip bridge plug, including push cylinder, and push cylinder is fixed with the release lever;Release lever outer circumferential surface is sequentially arranged with central tube, slip seat and lower joint;Lower joint is fixedly connected with release lever by shearing pin;Central tube includes the connecting section and conical structure section that are sequentially arranged in axis direction, and connecting section is butted with push cylinder;Slip seat one end is set on conical structure section, and other end is fixed with lower joint;There is step surface between connecting section and conical structure section, and step surface and conical structure section are set with rubber tube;Release lever outer circumferential surface is also set with connecting sleeve, and connecting sleeve is screwed with central tube by its threaded connecting section, and is clamped with lower joint by its clamping section.The central tube structure of the utility model can make rubber tube and slip seat directly set on central tube, reduce the axial length of whole bridge plug, improve the adaptability of bridge plug in downhole limited space.

Description

Technical Field

[0001] This utility model relates to the technical field of oil and gas well packing tools, specifically to a compression-type rubber sleeve single slip bridge plug. Background Technology

[0002] In the process of fracturing vertical or horizontal wells in oilfields, bridge plugs are the core tools for operations such as horizontal well fracturing. Their compact structure, ease of assembly, and operational reliability directly affect the construction efficiency. Among existing bridge plugs, single-slip types are widely used in the development of unconventional oil and gas reservoirs due to their fewer components, lower cost, and convenient post-processing. However, their overall length and structural complexity still need to be optimized due to limitations in the layout of sealing components and the dispersed design of functional parts.

[0003] For example, patent CN211230377U discloses a single-slip soluble bridge plug, whose structure includes a central tube. From top to bottom, the outer side of the central tube is fitted with a sealing assembly, a back ring assembly, a cone, a single-slip assembly, and a locking ring. The sealing assembly is constrained by a limiting part on the central tube. Although this structure simplifies the overall layout with a single-slip design, it has significant drawbacks: It achieves sealing by setting an independent cone on the central tube to abut against and push the slip seat to form an axial fit. This axially superimposed design significantly increases the bridge plug length, not only increasing assembly difficulty and cost but also resulting in poor adaptability to small wellbores. Simultaneously, this design makes the force transmission path too long, causing asynchronous response between the expansion of the rubber sleeve and the anchoring of the slip teeth, thus reducing the reliability of the sealing anchoring.

[0004] Therefore, in order to meet the demand for "more compact, easier to assemble, and more reliable" bridge plugs for efficient operations, it is necessary to optimize the structural design of existing single-slip bridge plugs and improve their overall performance to adapt to complex downhole conditions. Utility Model Content

[0005] The purpose of this invention is to provide a compression-type rubber sleeve single-slip bridge plug that can meet the performance requirements of "more compact, easier to assemble, and more reliable" bridge plugs, so as to adapt to complex downhole working conditions.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A compression-type single-latch bridge plug includes: a push cylinder, a release lever coaxially distributed with the push cylinder and fixedly connected to the center of the push cylinder; a central tube, a slip seat, and a lower connector are sequentially arranged on the outer circumference of the release lever; and the lower connector is fixedly connected to the release lever by a shear pin; the central tube includes a connecting section and a tapered structural section arranged axially in sequence, the end of the connecting section away from the tapered structural section abutting against the push cylinder; one end of the slip seat is sleeved on the end of the tapered structural section away from the connecting section, and the other end of the slip seat abuts against the lower connector. The connecting section has an outer diameter larger than the maximum outer diameter of the tapered structural section, so that a stepped surface is formed between the connecting section and the tapered structural section; a rubber sleeve is fitted onto the tapered structural section between the stepped surface and the slip seat; a connecting sleeve is also fitted onto the outer circumference of the release lever, one end of the connecting sleeve being a threaded connecting section and the other end being a snap-fit ​​section; a first sawtooth thread surface is provided on the inner surface of the central tube, and a second sawtooth thread surface is provided on the threaded connecting section to mate with the first sawtooth thread; the snap-fit ​​section is snap-fit ​​connected to the lower connector.

[0008] Preferably, the rubber tube has a first conical surface on the side near the stepped surface; the diameter of the first conical surface gradually increases from the end near the stepped surface to the end away from the stepped surface; an inner protective ring is fitted on the first conical surface, and an outer protective ring abuts against the outer circumference of the inner protective ring; a spiral washer is provided between the rubber tube and the slip seat, with one side of the spiral washer abutting against the rubber tube and the other side abutting against the slip seat; the rubber tube has a second conical surface adapted to the conical structural section, and the rubber tube abuts against the conical structural section of the central tube through the second conical surface; a stress relief groove is formed on the second conical surface.

[0009] Preferably, the slip seat is provided with a plurality of slip teeth, the tips of which protrude from the outer circumferential surface of the slip seat; a hoop is also fitted inside the slip seat, the hoop being located on the side of the slip seat that contacts the lower connector.

[0010] Preferably, the lower connector includes a first lower connector and a second lower connector; one side of the first lower connector abuts against the slip seat; the other side is threadedly connected to the second lower connector; an annular groove is formed on the inner circumferential surface of the first lower connector, and the snap-fit ​​section of the connecting sleeve is provided with an annular protrusion that snaps into the annular groove; multiple grooves are formed on the outer circumferential surface of the first lower connector, and a gauge-protecting tooth is embedded in each of the multiple grooves.

[0011] The beneficial effects of this utility model are:

[0012] 1. The central tube of this utility model adopts an integrated stepped structure (connecting section - stepped surface - conical structure section), which allows the rubber sleeve and slip seat to be directly fitted onto the central tube, eliminating the need for the independent conical body and corresponding connecting structure in traditional bridge plugs. This significantly shortens the axial assembly length of the bridge plug and greatly improves its adaptability to small wellbore or space-constrained well conditions. The integrated structure also simplifies the assembly process, eliminates the tolerance accumulation of multiple parts interfaces, reduces the risk of leakage and failure, and fundamentally solves the technical bottlenecks of traditional bridge plugs, such as excessive axial length, low force efficiency, and insufficient stability.

[0013] 2. This utility model forms a mechanical interlock to prevent retraction by setting a connecting sleeve that engages with the threaded connection of the central tube. After setting and anchoring, this interlock structure can strongly prevent the bridge plug from retracting, significantly improving anchoring stability. During assembly, utilizing the thread engagement characteristics, only a rotation operation is required to quickly and accurately assemble the connecting sleeve with the central tube, simplifying the installation process and meeting the high-efficiency operation requirements of downhole tools.

[0014] 3. This utility model features a hoop ring fitted inside the slip seat, providing radial restraint force to effectively prevent the slip teeth from accidentally falling off before operation and in the early stages of setting, ensuring the structural integrity of the slip seat. Simultaneously, this restraint force ensures that during the expansion of the slip seat along the central tube conical surface during setting, multiple slip teeth can move collaboratively, achieving uniform and synchronous radial expansion, thus reliably anchoring the sleeve wall. Furthermore, the hoop ring withstands the tension deformation of the slip seat during expansion, helping to smoothly transmit the expansion force, optimize the stress distribution of components, and enhance the overall rigidity of the slip assembly, significantly improving the stability and reliability of the setting action.

[0015] 4. This utility model provides diameter-maintaining teeth in the groove on the outer periphery of the first lower connector. During the process of lowering the bridge plug into the wellbore, the diameter-maintaining teeth preferentially contact and support the casing wall. This serves as a wear-resistant contact point to effectively prevent direct friction damage or jamming of the first lower connector body, and also supports and maintains the minimum outer diameter of the lower end of the tool, ensuring the smooth passage of the bridge plug in curved well sections or reduced-diameter casings, and ensuring successful lowering to the target position. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a compression-type rubber cylinder single-slip bridge plug in a static state according to an embodiment of the present invention;

[0017] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0018] Figure 3 This is a schematic diagram of the structure of a compression-type rubber sleeve single-slip bridge plug during the setting process according to an embodiment of the present invention;

[0019] Figure 4This utility model provides a schematic diagram of the structure of a compression-type rubber cylinder single-slip bridge plug after setting;

[0020] Figure 5 This is a schematic diagram of the structure of the central tube in an embodiment of the present invention.

[0021] Reference numerals: 100-sleeve, 200-push cylinder, 300-center tube, 301-connecting section, 302-stepped surface, 303-conical structure section, 400-release lever, 500-rubber sleeve, 610-outer protective ring, 611-inner protective ring, 620-spiral washer ring, 630-slip seat, 631-slip tooth, 632-hoop ring, 700-connecting sleeve, 810-first lower connector, 811-second lower connector, 812-gauge protection tooth, 813-shearing pin, 900-soluble float. Detailed Implementation

[0022] The specific embodiments of this utility model are described below with reference to the accompanying drawings.

[0023] Example 1

[0024] like Figures 1 to 5 As shown, this embodiment discloses a compression-type rubber sleeve single-slip bridge plug, including a push cylinder 200. A release lever 400 is fixedly connected to the center of the push cylinder 200 and is coaxially distributed with the push cylinder 200. A central tube 300, a slip seat 630 and a lower connector are arranged sequentially on the outer circumference of the release lever 400. The lower connector is fixedly connected to the release lever 400 through a shear pin 813. When a certain shearing force is reached, the shear pin 813 breaks, and the release function can be realized.

[0025] The central tube 300 includes a connecting section 301 and a tapered structural section 303 arranged axially in sequence. The end of the connecting section 301 away from the tapered structural section 303 abuts against the push cylinder 200, thereby transmitting the thrust of the push cylinder 200 to the tapered structural section 303 of the central tube 300. One end of the clamp seat 630 is sleeved on the end of the tapered structural section 303 away from the connecting section 301, and the other end of the clamp seat 630 abuts against the lower connector. The outer diameter of the connecting section 301 is larger than the maximum outer diameter of the tapered structural section 303, so that a stepped surface 302 is formed between the connecting section 301 and the tapered section 303. A rubber sleeve 500 is sleeved on the tapered structural section 303 between the stepped surface 302 and the clamp seat 630. The tapered section 303 provides a guiding and supporting foundation for the radial expansion of the rubber sleeve 500 and the radial movement of the clamp seat 630. A connecting sleeve 700 is also fitted on the outer circumference of the release lever 400. One end of the connecting sleeve 700 is a threaded connection section, and the other end is a snap-fit ​​section. The inner surface of the central tube 300 is provided with a first sawtooth thread surface, and the threaded connection section is provided with a second sawtooth thread surface that mates with the first sawtooth thread. The central tube 300 and the connecting sleeve 700 are connected by the threaded engagement of the first sawtooth thread surface and the second sawtooth thread surface, which facilitates the assembly of the bridge plug and prevents the central tube 300 from retracting after the rubber sleeve 500 is sealed. The snap-fit ​​section is snap-fit ​​connected to the lower connector.

[0026] A first conical surface is provided on the side of the rubber sleeve 500 near the step surface 302; the diameter of the first conical surface gradually increases from the end near the step surface 302 to the end away from the step surface 302; an inner protective ring 611 is fitted on the first conical surface, and an outer protective ring 610 abuts against the outer circumference of the inner protective ring 611. In this embodiment, the outer protective ring and the inner protective ring together form a back ring assembly. The outer protective ring 610 can restrict the axial movement of the rubber sleeve 500, allowing the rubber sleeve 500 to expand radially. At the same time, when the outer protective ring 610 is compressed and deformed, the inner protective ring 611 can fill the gap of the expansion and deformation of the outer protective ring 610, preventing the rubber sleeve 500 from cracking axially.

[0027] A spiral washer 620 is provided between the rubber cylinder 500 and the slip seat 630. One side of the spiral washer 620 abuts against the rubber cylinder 500 and the other side abuts against the slip seat 630. When the rubber cylinder 500 is squeezed, the spiral washer 620 can appropriately buffer the transmission of force and at the same time help limit the axial movement of the rubber cylinder 500.

[0028] The rubber sleeve 500 is provided with a second conical surface that is adapted to the conical structural section 303. The rubber sleeve 500 abuts against the conical structural section 303 of the central tube 300 through the second conical surface. A stress relief annular groove is provided on the second conical surface. When the rubber sleeve 500 is deformed by compression, the internal stress can be released through the stress relief groove to avoid damage to the rubber sleeve 500 due to stress concentration, and to ensure the structural stability and sealing reliability of the rubber sleeve 500.

[0029] The slip seat 630 is fitted with multiple slip teeth 631, the tips of which protrude from the outer circumferential surface of the slip seat 630. The slip teeth 631 are used to contact and bite against the inner wall of the sleeve 100, thereby anchoring the bridge plug within the sleeve 100. A clamping ring 632 is also fitted inside the slip seat 630. The clamping ring 632 is located on the side of the slip seat 630 that contacts the lower connector. The clamping ring 632 is used to constrain the slip seat 630, ensuring the structural integrity of the slip seat 630. At the same time, when the slip teeth 631 are opened by radial force, the clamping ring 632 can appropriately limit their excessive deformation.

[0030] The lower connector includes a first lower connector 810 and a second lower connector 811. One side of the first lower connector 810 abuts against the slip seat 630; the other side is threaded to the second lower connector 811. The inner circumferential surface of the first lower connector 810 has an annular groove, and the snap-fit ​​section of the connecting sleeve 700 has an annular protrusion that snaps into the annular groove. The outer circumferential surface of the first lower connector 810 has multiple grooves, and each groove is fitted with a diameter-protecting tooth 812. The diameter-protecting tooth 812 is glued into the groove, and the diameter-protecting tooth 812 serves to protect the outer circumferential surface of the lower connector and to help stabilize the position of the bridge plug within the sleeve 100.

[0031] like Figure 3 As shown, after the setting operation begins, the setting force pushes the pusher 200, and the thrust is transmitted to the rubber sleeve 500, the slip seat 630, and the lower connector through the central tube 300. Under the axial limiting action, the rubber sleeve 500 expands radially and gradually fits against the inner wall of the sleeve 100. The slip seat 630 drives the slip teeth 631 to move towards the inner wall of the sleeve 100. The shear force borne by the shear pin 813 is still within its design tolerance range and has not yet broken. The components continue to advance the setting process through coordinated action.

[0032] like Figure 4 As shown, after setting, the rubber sleeve 500 fully expands to achieve a seal, the slip teeth 631 fully engage with the inner wall of the casing 100 to complete anchoring, the shear pin 813 breaks, the release lever 400 separates from the bridge plug and is retrieved, and the soluble float 900 is dropped in to seal the inner diameter of the bridge plug. At this point, fracturing operations can be carried out. Under high pressure, the fracturing fluid effectively fractures the target formation. After the fracturing operation is completed, the bridge plug dissolution process is initiated until the bridge plug completely disappears, the casing 100 returns to its full-bore state, and the entire bridge plug operation completes its corresponding process.

[0033] In summary, this embodiment, through the integrated stepped structure center tube 300 (connecting section 301-step surface 302-conical structure section 303), allows the rubber sleeve 500 and the slip seat 630 to be directly fitted onto the center tube 300, eliminating the need for the independent conical body and corresponding connecting structure in traditional bridge plugs, significantly shortening the axial assembly length of the bridge plug. At the same time, the sawtooth thread engagement prevents the center tube 300 from retracting, and the synergistic effect of the inner retaining ring 611 and the outer retaining ring 610 ensures the sealing performance of the rubber sleeve 500. Anchoring is achieved by the clamping of the slip teeth 631 with the inner wall of the sleeve 100, thus realizing reliable sealing and stable anchoring of the bridge plug within the sleeve.

[0034] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A compression-type rubber sleeve single-slip bridge plug, characterized in that, include: A push cylinder, wherein a release lever is fixedly connected to the center of the push cylinder and distributed coaxially with the push cylinder; a central tube, a locking seat and a lower connector are arranged sequentially on the outer circumference of the release lever; and the lower connector is fixedly connected to the release lever by a shear pin; The central tube includes a connecting section and a tapered structural section arranged axially in sequence. The end of the connecting section away from the tapered structural section abuts against the push cylinder. One end of the slip seat is sleeved on the end of the tapered structural section away from the connecting section, and the other end of the slip seat abuts against the lower connector. The outer diameter of the connecting section is larger than the maximum outer diameter of the tapered structural section, so that a stepped surface is formed between the connecting section and the tapered structural section; a rubber sleeve is fitted onto the tapered structural section between the stepped surface and the locking seat; A connecting sleeve is also fitted on the outer circumference of the release lever. One end of the connecting sleeve is a threaded connection section, and the other end of the connecting sleeve is a snap-fit ​​section. The inner surface of the central tube is provided with a first sawtooth thread surface, and the threaded connection section is provided with a second sawtooth thread surface that mates with the first sawtooth thread. The snap-fit ​​section is snap-fitted to the lower connector.

2. The extrusion-type single-latch bridge plug according to claim 1, characterized in that: The rubber tube has a first conical surface on the side near the step surface; the diameter of the first conical surface gradually increases from the end near the step surface to the end away from the step surface; an inner protective ring is fitted on the first conical surface, and an outer protective ring abuts against the outer circumference of the inner protective ring.

3. The extrusion-type single-latch bridge plug according to claim 1, characterized in that: A spiral washer is provided between the rubber tube and the slip seat, with one side of the spiral washer abutting against the rubber tube and the other side abutting against the slip seat.

4. The extrusion-type single-latch bridge plug according to claim 1, characterized in that: The rubber tube is provided with a second conical surface adapted to the conical structural section, and the rubber tube abuts against the conical structural section of the central tube through the second conical surface; a stress relief annular groove is formed on the second conical surface.

5. The extrusion-type single-latch bridge plug according to claim 1, characterized in that: The slip seat is provided with multiple slip teeth, and the tips of the slip teeth protrude from the outer circumferential surface of the slip seat.

6. The extrusion-type single-latch bridge plug according to claim 1, characterized in that: The slip seat is also fitted with a hoop ring, which is located on the side of the slip seat that contacts the lower connector.

7. The extrusion-type single-latch bridge plug according to claim 1, characterized in that: The lower connector includes a first lower connector and a second lower connector; one side of the first lower connector abuts against the slip seat; the other side is threadedly connected to the second lower connector.

8. The extrusion-type single-latch bridge plug according to claim 7, characterized in that: The inner circumferential surface of the first lower connector is provided with an annular groove, and the snap-fit ​​section of the connecting sleeve is provided with an annular protrusion that snaps into the annular groove.

9. The extrusion-type single-latch bridge plug according to claim 7, characterized in that: The outer circumferential surface of the first lower connector is provided with multiple grooves, and each of the multiple grooves is embedded with a diameter-maintaining tooth.

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