A downhole packer

Abstract

The application provides a downhole packer, which comprises a sleeve, a rubber sleeve arranged in the sleeve, a first blocking ring, a second blocking ring and a sealing ring, the sleeve has a preset sealing pipe section, the sealing ring is arranged in the preset sealing pipe section, the first blocking ring and the second blocking ring are respectively located at two ends of the rubber sleeve in the axial direction, and after the rubber sleeve enters the preset sealing pipe section, the sealing ring can move towards the first blocking ring and the second blocking ring and contact the end faces of the first blocking ring and the second blocking ring to constrain the deformation of the rubber sleeve in the axial direction. The application can effectively avoid the shoulder of the rubber sleeve from protruding and improve the sealing performance of the rubber sleeve by constraining the deformation of the rubber sleeve in the axial direction.

Description

Technical Field

[0001] This invention relates to the field of oil drilling technology, and more specifically, to a downhole packer. Background Technology

[0002] Currently, the commonly used downhole sealing device is the packer, which forms a seal by axially compressing a rubber sleeve and causing it to expand radially to the inner diameter of the casing. During the compression process of the rubber sleeve, the upper and lower ends of the sleeve bear the greatest pressure, causing a shoulder (a protruding part caused by the compression of the upper and lower end faces of the rubber sleeve by the retaining ring) to protrude. When the stress generated by the shoulder protrusion exceeds the allowable stress of the rubber sleeve material, it will cause the rubber sleeve seal to fail.

[0003] Chinese invention patent CN112282690A discloses an expansion packer with a protective structure on the shoulder of a rubber sleeve and resistance to high temperature and pressure, relating to the field of oilfield downhole tool technology. It includes a central tube and a rubber sleeve, with the sleeve installed on the outside of the central tube. Both ends of the sleeve are fixedly and sealed to the central tube. A hoop is provided on the outer side of each end of the sleeve. A fluid passage is provided on the central tube corresponding to the inner space of the sleeve. An outer retaining ring and an inner retaining ring are provided between the hoop and the sleeve. The inner retaining ring is fitted onto the outside of the sleeve, and the outer retaining ring is fitted onto the outside of the inner retaining ring. Both the outer and inner retaining rings are fixedly connected to the hoop by screws. Multiple axial slits are provided at one end of both the outer and inner retaining rings. The elastic claw on the outer retaining ring is called the outer elastic claw, and the elastic claw on the inner retaining ring is called the inner elastic claw. The outer and inner elastic claws are staggered. This design incorporates an outer and inner retaining ring at the end of the rubber sleeve, which effectively improves the pressure resistance of the expansion packer, but cannot prevent the shoulder of the rubber sleeve from protruding.

[0004] Chinese invention patent CN104213864A discloses a rubber tube protection device, installed on both ends of a rubber tube on a packer. The device consists of an inner protective bowl, an outer protective bowl, a cone, a slider, and a sliding groove seat, installed sequentially from one end of the rubber tube outwards. The inner and outer protective bowls each have at least six axial slits. One side of the outer protective bowl overlaps with the inner protective bowl. The other side of the outer protective bowl is in close contact with the cone. The outer wall of the cone has an outer conical surface, which mates with an inner conical surface on one side of the slider. At least ten guide heads are provided along the circumference of the other side of the slider. A corresponding number of grooves are provided on one side of the sliding groove seat, and the guide heads are installed in the corresponding grooves. This solution can only alleviate the shoulder protrusion phenomenon of the rubber tube to a certain extent and improve the pressure-bearing capacity of the rubber tube, but it cannot effectively prevent the rubber tube from protruding.

[0005] Therefore, there is an urgent need for a downhole packer that can effectively avoid the technical drawback of the rubber sleeve's shoulder protruding, which could lead to the failure of the rubber sleeve seal. Summary of the Invention

[0006] One object of the present invention is to provide a downhole packer that effectively prevents the shoulder of the packer from protruding by constraining the axial deformation of the packer, thereby improving the sealing performance of the packer.

[0007] According to the present invention, a downhole packer is provided, comprising a casing, a rubber sleeve disposed within the casing, a first retaining ring, a second retaining ring, and a sealing ring. The casing has a pre-set sealing section, and the sealing ring is disposed within the pre-set sealing section. The first retaining ring and the second retaining ring are respectively located at both ends of the rubber sleeve along the axial direction. After the rubber sleeve enters the pre-set sealing section, the sealing ring can move towards the first retaining ring and the second retaining ring and contact the end faces of the first retaining ring and the second retaining ring to constrain the axial deformation of the rubber sleeve.

[0008] In a preferred embodiment, the downhole packer further includes a positioning part disposed above the first retaining ring and a driving part disposed on the pre-set sealing pipe section for driving the sealing ring to move. The casing has a mating section above the pre-set sealing pipe section. When the positioning part moves close to the mating section, the driving part can drive the sealing ring to move towards the side end face of the first retaining ring and the second retaining ring so as to contact the side end face of both.

[0009] In a preferred embodiment, the positioning part contains an RFID tag, the mating section contains an RFID sensor and a control circuit connected to the RFID sensor, and the driving part includes a motor and a lead screw connected to the motor. When the positioning part moves close to the mating section, the RFID sensor can read the RFID tag and start the motor through the control circuit. The motor can then drive the lead screw, and the lead screw can then drive the sealing ring closer to the first retaining ring and the second retaining ring.

[0010] In a preferred embodiment, the sealing ring is configured as a hollow semi-cylindrical shape.

[0011] In a preferred embodiment, the side end face of the sealing ring near the first and second retaining rings can press against the side end faces of the first and second retaining rings, and the inner wall of the hollow space formed therein forms a groove for accommodating the deformed rubber tube.

[0012] In a preferred embodiment, the downhole packer further includes an anchoring component, and the casing is provided with a pre-set anchoring section above the mating section, the anchoring component being able to anchor and engage with the pre-set anchoring section.

[0013] In a preferred embodiment, the outer peripheral surface of the anchoring component is provided with an anchoring claw, and the inner wall of the pre-set anchoring section is provided with a mating groove, and the anchoring claw can be anchored to the mating groove.

[0014] In a preferred embodiment, the outer diameter of the positioning part is smaller than the inner diameter of the preset anchoring section.

[0015] In a preferred embodiment, the inner surface of the sealing ring is provided with a plurality of grooves. When the rubber tube is compressed in the axial direction, a portion of the rubber tube can enter the grooves and a portion of the outer surface of the rubber tube can be pressed into contact with both the inner wall and the bottom surface of the grooves.

[0016] In a preferred embodiment, the inner surface of the sealing ring is provided with a plurality of protrusions. When the rubber tube is compressed in the axial direction, a portion of the rubber tube can enter the recessed area between the protrusions, and a portion of the outer surface of the rubber tube can be pressed into contact with the recessed area and the side surface of each protrusion.

[0017] In a preferred embodiment, the inner surface of the sealing ring is provided with a plurality of protrusions and a plurality of grooves. When the rubber tube is compressed in the axial direction, a portion of the rubber tube can enter between the protrusions and inside the grooves. A portion of the outer surface of the rubber tube can be in compression contact with the surfaces between the protrusions, the inner walls of the grooves, and the bottom surface.

[0018] In a preferred embodiment, the groove and / or the protrusion extend circumferentially on the inner surface of the sealing tube section.

[0019] This invention features a sealing ring positioned within a pre-sealed pipe section, with a first retaining ring and a second retaining ring located at opposite ends of the rubber tube's axial direction. After the rubber tube enters the pre-sealed pipe section, the sealing ring moves towards and contacts the side faces of the first and second retaining rings, effectively reducing the gap between the first and second retaining rings and the pre-sealed pipe section. Simultaneously, the sealing ring, first retaining ring, and second retaining ring effectively restrict the axial deformation of the rubber tube, preventing the shoulder of the rubber tube from protruding. This effectively avoids failure due to shoulder protrusion and improves the service life of the rubber tube.

[0020] Because the sleeve of the present invention has a pre-set sealing section and a sealing ring is set in the pre-set sealing section, and the sealing ring can contact the side end faces of the first retaining ring and the second retaining ring, the sealing ring, the first retaining ring and the second retaining ring are used to constrain the axial deformation of the rubber sleeve. After the rubber sleeve expands radially, it is housed in the sealing ring. On the one hand, the upper and lower end faces of the sealing ring can provide axial support for the rubber sleeve. On the other hand, since the distance between the inner wall of the sealing ring and the outer surface of the central tube is less than the distance between the inner wall of the sleeve and the outer surface of the central tube, the radial expansion distance of the rubber sleeve can be shortened, which can improve the stress distribution of the rubber sleeve and thus effectively reduce the axial shear force it receives when under pressure. At the same time, since the radial expansion distance is shortened, the density performance can be further improved by increasing the material hardness.

[0021] This invention includes a positioning part disposed above a first retaining ring and a driving part disposed on a pre-set sealing tube section for driving the sealing ring to move. The sleeve has a mating section above the pre-set sealing tube section. When the positioning part moves close to the mating section, the driving part can drive the sealing ring to move towards the side end faces of the first and second retaining rings to contact the side end faces of both. When the positioning part moves close to the mating section, it can trigger the driving part to drive the sealing ring to move. After the rubber tube is in the pre-set sealing tube section, the sealing ring makes abutting contact with the side end faces of the first and second retaining rings, ensuring accurate positioning of the rubber tube, improving positioning efficiency and reducing preparation time before setting the seal.

[0022] The present invention utilizes a sealing ring that can press against the side end faces of the first and second retaining rings, and the inner wall of the hollow space formed therein forms a groove for accommodating the deformed rubber tube. When the rubber tube fills the groove, the groove can also provide axial support to the rubber tube, enabling the rubber tube to withstand a large pressure difference and improving the sealing performance of the rubber tube.

[0023] The present invention includes an anchoring component located above the positioning part, and a pre-set anchoring section is provided above the mating section of the sleeve, and the anchoring component can be anchored and mated with the pre-set anchoring section. The structure that needs to be anchored and mated can be pre-installed to the required position through the pre-set anchoring section, which improves the anchoring performance without damaging the sleeve.

[0024] This invention features multiple grooves on the inner surface of the sealing ring. When the rubber tube is compressed in the axial direction, a portion of the rubber tube can enter the grooves, and part of the outer surface of the rubber tube can make compression contact with the inner wall and bottom surface of the grooves. This allows the sleeve to bear part of the shear stress on the rubber tube through the grooves, thereby alleviating the damage caused by shear stress to the rubber tube. The sleeve provides axial support to the rubber tube, thus mitigating the damage caused by axial shear stress. This improves the reliability of the rubber tube while enhancing its sealing performance. Attached Figure Description

[0025] Figure 1 A schematic diagram of a downhole packer including the present invention is shown.

[0026] Figure 2 Another structural schematic diagram of a downhole packer including the present invention is shown schematically.

[0027] In this application, all drawings are schematic and are used only to illustrate the principles of the invention, and are not drawn to scale. Detailed Implementation

[0028] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

[0029] In the description of this invention, it should be understood that the terms "inner", "outer", "axial", "radial", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0030] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0031] In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0032] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] Figure 1A schematic diagram of an overall structure of the downhole packer of the present invention is shown. As shown, the downhole packer 100 of the present invention includes a casing 1002, a rubber sleeve 1006 disposed within the casing 1002, a first retaining ring 1007, a second retaining ring 1009, and a sealing ring 1010. The casing 1002 has a pre-set sealing section 10021 for completing the setting. The sealing ring 1010 is disposed within the pre-set sealing section 10021 and is used to cooperate with the deformed rubber sleeve 1006 to achieve a seal. The first retaining ring 1007 and the second retaining ring 1009 are respectively located within the rubber sleeve. At its upper and lower ends in the axial direction, 1006 is in contact with the rubber sleeve 1006. Before the setting begins, after the rubber sleeve 1006, the first retaining ring 1007, and the second retaining ring 1009 can enter the pre-sealed section 10021 inside the sleeve 1002, the sealing ring 1010 can move towards the first retaining ring 1007 and the second retaining ring 1009 and in contact with their side end faces to constrain the axial deformation of the rubber sleeve 1006. The pre-sealed section 10021 is annular.

[0034] The practical application of the downhole packer 100 described in this invention will be explained below. The first end of the central tube 1001 is close to the ground. A packer is installed near the second end of the central tube 1001. The second end of the central tube 1001 is located inside the well. The rubber sleeve 1006 is sleeved on the outer periphery of the central tube 1001. Before setting, the casing 1002 is lowered into the well. Then, the central tube 1001 together with the rubber sleeve 1006 is lowered into the casing 1002. After the rubber sleeve 1006 enters the pre-sealed pipe section 10021 of the casing 1002, the sealing ring 1010 can move towards the first retaining ring 1007 and the second retaining ring 1009 and contact the side end faces of the first retaining ring 1007 and the second retaining ring 1009 to constrain the deformation of the rubber sleeve 1006 in the axial direction. During the setting process, by squeezing the rubber sleeve 1006 in the axial direction, the rubber sleeve 1006 can fill the internal space of the sealing ring 1010 through radial deformation and press against its inner wall to achieve sealing.

[0035] During the setting process, the two ends of the rubber sleeve 1006 in the axial direction are squeezed, and its shoulder is prone to protrusion, which may cause the rubber sleeve 1006 to fail. Due to the space between the first retaining ring 1007, the second retaining ring 1009 and the pre-set sealing pipe section 10021, part of the rubber sleeve 1006 may be squeezed out of the gap between the first retaining ring 1007, the second retaining ring 1009 and the pre-set sealing pipe section 10021, which may cause the shoulder of the rubber sleeve 1006 to protrude too much. This invention uses a sealing ring 1010 disposed within a pre-sealed pipe section 10021, with a first retaining ring 1007 and a second retaining ring 1009 located at opposite ends of the axial direction of the rubber sleeve 1006. After the rubber sleeve 1006 enters the pre-sealed pipe section 10021, the sealing ring 1010 can move towards the first retaining ring 1007 and the second retaining ring 1009 and contact their side surfaces. This effectively reduces the gap between the first retaining ring 1007 and the second retaining ring 1009 and the pre-sealed pipe section 10021. Simultaneously, the sealing ring 1010, the first retaining ring 1007, and the second retaining ring 1009 effectively restrict the axial deformation of the rubber sleeve 1006, preventing the shoulder of the rubber sleeve 1006 from protruding. This effectively avoids failure of the rubber sleeve 1006 due to shoulder protrusion and improves the service life of the rubber sleeve 1006.

[0036] Furthermore, since the sleeve 1002 of the present invention has a pre-set sealing section 10021 and a sealing ring 1010 is disposed within the pre-set sealing section 10021, and the sealing ring 1010 can contact the side end faces of the first retaining ring 1007 and the second retaining ring 1009, the sealing ring 1010, the first retaining ring 1007, and the second retaining ring 1009 are used to constrain the axial deformation of the rubber sleeve 1006. After radial expansion, the rubber sleeve 1006 is accommodated within the sealing ring 1010. On the one hand, the sealing ring 1010 The upper and lower end faces can provide axial support for the rubber sleeve 1006. On the other hand, since the distance between the inner wall of the sealing ring and the outer surface of the central tube 1001 is less than the distance between the inner wall of the sleeve 1002 and the outer surface of the central tube 1001, the radial expansion distance of the rubber sleeve 1006 can be shortened, which can improve the stress distribution of the rubber sleeve 1006 and effectively reduce the axial shear force it is subjected to when under pressure. At the same time, due to the shortened radial expansion distance, the density performance can be further improved by increasing the material hardness.

[0037] In one or more embodiments, the downhole packer 100 of the present invention further includes a positioning part 1020 and a driving part disposed on a pre-set sealing pipe section 10021 for driving the sealing ring 1010 to move. The positioning part 1020 is sleeved on the outer periphery of the central pipe 1001 and located above the first retaining ring 1007. The sleeve 1002 has a mating section 1030 above the pre-set sealing pipe section 10021. When the positioning part 1020 moves close to the mating section 1030, the driving part can drive the sealing ring 1010 to move closer to the side end faces of the first retaining ring 1007 and the second retaining ring 1009 so as to contact the side end faces of the two.

[0038] The contact points where the positioning part 1020 contacts the mating section 1030 are both constructed as inclined surfaces. During the downward movement of the central tube 1001, the positioning part 1020 can approach and contact the mating section 1030. During this process, the driving part drives the sealing ring 1010 to move towards the side end faces of the first retaining ring 1007 and the second retaining ring 1009. After that, the positioning part 1020 and the mating section 1030 slide relative to each other, and the central tube 1001 can continue to move downward until the positioning part 1020 is stuck by the inclined surface of the mating section 1030 and cannot continue to move downward. At this time, the rubber sleeve 1006 is in place in the pre-sealed tube section 10021, and the sealing ring 1010 abuts against the side end faces of the first retaining ring 1007 and the second retaining ring 1009.

[0039] This invention includes a positioning part 1020 disposed above the first retaining ring 1007 and a driving part disposed on the pre-set sealing tube section 10021 for driving the sealing ring 1010 to move; the sleeve 1002 has a mating section 1030 above the pre-set sealing tube section 10021; when the positioning part 1020 moves close to the mating section 1030, the driving part can drive the sealing ring 1010 to move closer to the side end faces of the first retaining ring 1007 and the second retaining ring 1009 to contact the side end faces of both; when the positioning part 1020 moves close to the mating section 1030, the driving part can trigger the driving part to drive the sealing ring 1010 to move; and after the glue tube 1006 is in the pre-set sealing tube section 10021, the sealing ring 1010 makes abutting contact with the side end faces of the first retaining ring 1007 and the second retaining ring 1009, ensuring accurate positioning of the glue tube 1006, improving positioning efficiency and reducing preparation time before setting the seal.

[0040] like Figure 2As shown, in one or more embodiments, an RFID tag 1040 is provided in the positioning part 1020, and an RFID sensor 1050 and a control circuit 1060 connected to the RFID sensor 1050 are provided in the mating section 1030 near the positioning part 1020. The driving part includes a motor 1070 and a lead screw 1080 connected to the motor 1070. The lead screw 1080 is connected to the sealing ring 1010 and can convert the rotational motion of the output shaft of the motor 1070 into linear motion, thereby driving the sealing ring 1010 to move along the side end face near the first retaining ring 1007 and the second retaining ring 1009. When the positioning part 1020 moves to near the mating section 1030, the RFID sensor 1050 can read the RFID tag 1040 and start the motor 1070 through the control circuit 1060. The motor 1070 can then drive the lead screw 1080, and the lead screw 1080 can then drive the sealing ring 1010 in the direction near the first retaining ring 1007 and the second retaining ring 1009. The control circuit 1060 includes a microcontroller unit (MCU) and a power supply. The MCU is used for signal analysis, receives signals from the RFID sensor, and issues execution commands to the motor 1070. The power supply powers the RFID sensor 1050, the MCU, and the motor 1070.

[0041] Optionally, the RFID tag is positioned within the positioning section 1020 near the mating section 1030, and the RFID sensor is positioned within the mating section 1030 near the positioning section 1020, thereby facilitating the RFID sensor to read the information from the RFID tag 1040.

[0042] In one or more embodiments, the sealing ring 1010 is configured as a hollow semi-cylindrical shape. The invention includes two symmetrically distributed sets of RFID tags 1040, an RFID sensor 1050, and a drive unit.

[0043] In one or more embodiments, the side end face of the sealing ring 1010 near the first retaining ring 1007 and the second retaining ring 1009 can press against the side end face of the first retaining ring 1007 and the second retaining ring 1009, and the inner wall of the hollow space formed therein forms a groove for accommodating the deformed rubber tube 1006. After setting, the rubber tube 1006 can fill the groove.

[0044] The present invention utilizes the sealing ring 1010 to form a groove on the inner wall of the hollow space formed therein, which is close to the side end face of the first retaining ring 1007 and the second retaining ring 1009 and can press against the side end face of the first retaining ring 1007 and the second retaining ring 1009. This groove is used to accommodate the deformed rubber tube 1006. When the rubber tube 1006 fills the groove, the groove can also provide axial support to the rubber tube, so that the rubber tube can withstand a large pressure difference and improve the sealing performance of the rubber tube 1006.

[0045] In one or more embodiments, the downhole packer 100 of the present invention further includes an anchoring component 1090 located above the positioning part 1020, and the casing 1002 is provided with a pre-set anchoring section 1100 above the mating section 1030, and the anchoring component 1090 can be anchored and mated with the pre-set anchoring section 1100.

[0046] Existing technologies achieve anchoring through a slip-fitting sleeve, but this has the drawback of limited depth of engagement between the anchoring component and the inner wall of the sleeve. Under large axial forces, this can easily lead to anchoring failure. This invention includes an anchoring component 1090 located above the positioning part 1020, and a pre-set anchoring section 1100 provided above the mating section 1030 on the sleeve 1002. The anchoring component 1090 can anchor into the pre-set anchoring section 1100. The pre-set anchoring section 1100 allows the structure requiring anchoring to be pre-positioned, improving anchoring performance without damaging the sleeve 1002. Optionally, both the pre-set anchoring section 1100 and the pre-set sealing section 10021 are configured with beveled surfaces for easy insertion, and the beveled surface of the pre-set anchoring section 1100 can mate with the positioning part 1020.

[0047] In one or more embodiments, the outer peripheral surface of the anchoring component 1090 is provided with an anchoring claw 1091, and the inner wall of the pre-set anchoring section 1100 is provided with a mating groove 1101, and the anchoring claw 1091 can be anchored to the mating groove 1101.

[0048] When the positioning part 1020 contacts the mating section 1030, the anchoring claw 1091 of the anchoring component 1090 can be pushed radially outward along the central tube 1001 by hydraulic or mechanical drive until it is embedded in the mating groove 1101 of the pre-set anchoring section 1100. Compared with the prior art of anchoring by the engagement of the sleeve with slips, the present invention has an anchoring claw 1091 on the outer peripheral surface of the anchoring component 1090 and a mating groove 1101 on the inner wall of the pre-set anchoring section 1100, and the anchoring claw 1091 can be anchored in the mating groove 1101, which improves the anchoring performance without damaging the sleeve 1002.

[0049] In one or more embodiments, the outer diameter of the positioning part 1020 is smaller than the inner diameter of the preset anchoring section 1100, enabling the positioning part 1020 to smoothly pass through the preset anchoring section 1100 to contact and engage with the mating section 1030. Optionally, the outer diameter of the positioning part 1020 is larger than the inner diameter of the preset sealing pipe section 10021.

[0050] In one or more embodiments, the inner wall surface of the sealing ring 1010 is provided with a plurality of grooves, each groove being spaced a certain distance apart. During the setting process, after the rubber sleeve 1006 is compressed in the axial direction, a portion of the rubber sleeve 1006 can enter the interior of each groove, and a portion of the outer surface of the rubber sleeve 1006 can press against the inner wall and bottom surface of each groove. Optionally, the grooves extend in the circumferential direction.

[0051] Specifically, after the central tube 1001 and the rubber sleeve 1006 are inserted into the pre-sealed tube section 10021 inside the sleeve 1002, the rubber sleeve 1006 is deformed and fills the sealing ring 1010 by axially pressing the rubber sleeve 1006. The outer circumferential surface of the rubber sleeve 1006 is pressed into the groove, and a portion of the rubber sleeve 1006 forms a small protrusion that enters into each groove. Each small protrusion formed by the rubber sleeve 1006 can press and contact the inner wall and bottom surface of each groove respectively.

[0052] This invention utilizes a sealing ring 1010 with multiple grooves on its inner surface. When the rubber sleeve 1006 is compressed in the axial direction, a portion of the rubber sleeve 1006 can enter the grooves, and a portion of the outer surface of the rubber sleeve 1006 can be pressed into contact with the inner wall and bottom surface of the grooves. This allows the sleeve 1002 to bear part of the shear stress on the rubber sleeve 1006 through the grooves, thereby alleviating the damage to the rubber sleeve 1006 caused by shear stress. The sleeve 1002 provides support to the rubber sleeve 1006 in the axial direction to alleviate the damage to the rubber sleeve 1006 caused by axial shear stress, thus improving the reliability and sealing performance of the rubber sleeve 1006.

[0053] In one or more embodiments, the inner surface of the sealing tube section is provided with a plurality of protrusions. After the rubber tube 1006 is compressed in the axial direction, a portion of the rubber tube 1006 can enter the recessed area between the protrusions, and a portion of the outer surface of the rubber tube 1006 can be pressed into contact with both the recessed area between the protrusions and the side surface of each protrusion. Optionally, the protrusions extend in the circumferential direction.

[0054] Specifically, after the central tube 1001 and the rubber sleeve 1006 are inserted into the pre-sealed tube section 10021 inside the sleeve 1002, the rubber sleeve 1006 is deformed and fills the sealing ring 1010 by axially pressing the rubber sleeve 1006. After the outer peripheral surface of the rubber sleeve 1006 is pressed against each protrusion, a portion of the rubber sleeve 1006 forms a small protrusion that enters the concave area between each protrusion. The small protrusion formed by the rubber sleeve 1006 can press and contact the concave area and the side surface of each protrusion.

[0055] This invention features multiple protrusions on the inner surface of the sealing ring 1010. When the rubber sleeve 1006 is compressed in the axial direction, a portion of the rubber sleeve 1006 can enter the recessed area between the protrusions. A portion of the outer surface of the rubber sleeve 1006 can also be pressed into contact with the recessed area and the side surfaces of the protrusions. This allows the sleeve 1002 to bear part of the shear stress on the rubber sleeve 1006 through the protrusions, thereby alleviating the damage to the rubber sleeve 1006 caused by shear stress. The sleeve 1002 provides support to the rubber sleeve 1006 in the axial direction to alleviate the damage to the rubber sleeve 1006 caused by axial shear stress. This improves the reliability of the rubber sleeve 1006 and enhances its sealing performance.

[0056] In one or more embodiments, the inner surface of the sealing ring 1010 is provided with a plurality of protrusions and a plurality of grooves. After the rubber sleeve 1006 is compressed in the axial direction, a portion of the rubber sleeve 1006 can enter between the protrusions and inside the grooves. A portion of the outer surface of the rubber sleeve 1006 can make compression contact with the surfaces between the protrusions, the inner walls of the grooves, and the bottom surface. Optionally, both the grooves and protrusions extend in the circumferential direction. Optionally, the protrusions and grooves are spaced apart.

[0057] Specifically, after the central tube 1001 and the rubber sleeve 1006 are inserted into the pre-sealed tube section 10021 inside the sleeve 1002, the rubber sleeve 1006 is deformed and fills the sealing ring 1010 by axially pressing it. After the outer circumferential surface of the rubber sleeve 1006 is pressed against the various protrusions and grooves, a portion of the rubber sleeve 1006 forms a small protrusion, which enters the concave area between the protrusions and the interior of the groove. The small protrusion formed by the rubber sleeve 1006 can press and contact the surface between the protrusions, the inner wall of the groove and the bottom surface.

[0058] This invention features multiple protrusions and grooves on the inner surface of the sealing pipe section. When the rubber sleeve 1006 is compressed in the axial direction, a portion of the rubber sleeve 1006 can enter between the protrusions and inside the grooves. A portion of the outer surface of the rubber sleeve 1006 can also make compression contact with the surfaces between the protrusions, the inner wall of the groove, and the bottom surface. This allows the sleeve 1002 to bear part of the shear stress on the rubber sleeve 1006 through the protrusions and grooves, thereby alleviating the damage to the rubber sleeve 1006 caused by shear stress. The sleeve 1002 provides axial support to the rubber sleeve 1006 to mitigate the damage to the rubber sleeve 1006 caused by axial shear stress, thus improving the reliability and sealing performance of the rubber sleeve 1006.

[0059] The present invention also provides a downhole bridge plug, including the aforementioned downhole packer 100.

[0060] The present invention mainly has the following technical effects:

[0061] This invention uses a sealing ring 1010 disposed within a pre-sealed pipe section 10021, with a first retaining ring 1007 and a second retaining ring 1009 located at opposite ends of the axial direction of the rubber sleeve 1006. After the rubber sleeve 1006 enters the pre-sealed pipe section 10021, the sealing ring 1010 can move towards the first retaining ring 1007 and the second retaining ring 1009 and contact their side surfaces. This effectively reduces the gap between the first retaining ring 1007 and the second retaining ring 1009 and the pre-sealed pipe section 10021. Simultaneously, the sealing ring 1010, the first retaining ring 1007, and the second retaining ring 1009 effectively restrict the axial deformation of the rubber sleeve 1006, preventing the shoulder of the rubber sleeve 1006 from protruding. This effectively avoids failure of the rubber sleeve 1006 due to shoulder protrusion and improves the service life of the rubber sleeve 1006.

[0062] Because the sleeve 1002 of the present invention has a pre-set sealing section 10021 and a sealing ring 1010 is disposed within the pre-set sealing section 10021, and the sealing ring 1010 can contact the side end faces of the first retaining ring 1007 and the second retaining ring 1009, the sealing ring 1010, the first retaining ring 1007 and the second retaining ring 1009 are used to constrain the axial deformation of the rubber sleeve 1006. After radial expansion, the rubber sleeve 1006 is accommodated within the sealing ring 1010. On the one hand, the upper part of the sealing ring 1010... The lower end face can provide axial support for the rubber sleeve 1006. On the other hand, since the distance between the inner wall of the sealing ring and the outer surface of the central tube 1001 is less than the distance between the inner wall of the sleeve 1002 and the outer surface of the central tube 1001, the radial expansion distance of the rubber sleeve 1006 can be shortened, which can improve the stress distribution of the rubber sleeve 1006 and effectively reduce the axial shear force it is subjected to when under pressure. At the same time, due to the shortened radial expansion distance, the density performance can be further improved by increasing the material hardness.

[0063] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A downhole packer, characterized in that, include: The system comprises a first retaining ring, a second retaining ring, a sealing ring, a sleeve, and a rubber tube disposed within the sleeve. The sleeve has a pre-set sealing section, and the sealing ring is disposed within the pre-set sealing section. The first retaining ring and the second retaining ring are located at opposite ends of the rubber tube along its axial direction. After the rubber tube enters the pre-set sealing section, the sealing ring can move towards the first retaining ring and the second retaining ring and contact the end faces of the first retaining ring and the second retaining ring to constrain the axial deformation of the rubber tube.

2. The downhole packer according to claim 1, characterized in that, It also includes a positioning part disposed above the first retaining ring and a driving part disposed on the pre-set sealing tube section for driving the sealing ring to move. The sleeve has a mating section above the pre-set sealing tube section. When the positioning part moves to be close to the mating section, the driving part can drive the sealing ring to move towards the side end face close to the first retaining ring and the second retaining ring so as to contact the side end face of the two.

3. The downhole packer according to claim 2, characterized in that, The positioning part contains an RFID tag, and the mating section is equipped with an RFID sensor and a control circuit connected to the RFID sensor. The driving part includes a motor and a lead screw connected to the motor. When the positioning part moves close to the mating section, the RFID sensor can read the RFID tag and start the motor through the control circuit. The motor can then drive the lead screw, and the lead screw can then drive the sealing ring closer to the first retaining ring and the second retaining ring.

4. The downhole packer according to claim 1, characterized in that, The sealing ring is constructed as a hollow semi-cylindrical shape.

5. The downhole packer according to claim 4, characterized in that, The sealing ring can press against the side end face of the first and second retaining rings, and the inner wall of the hollow space formed therein forms a groove for accommodating the deformed rubber tube.

6. The downhole packer according to claim 2, characterized in that, It also includes an anchoring component, wherein the sleeve is provided with a pre-set anchoring section above the mating section, and the anchoring component can be anchored and mated with the pre-set anchoring section.

7. The downhole packer according to claim 6, characterized in that, The outer peripheral surface of the anchoring component is provided with an anchoring claw, and the inner wall of the pre-set anchoring section is provided with a mating groove, and the anchoring claw can be anchored to the mating groove.

8. The downhole packer according to claim 6, characterized in that, The outer diameter of the positioning part is smaller than the inner diameter of the preset anchoring section.

9. The downhole packer according to claim 2, characterized in that, The inner surface of the sealing ring is provided with multiple grooves. When the rubber tube is squeezed in the axial direction, part of the rubber tube can enter the groove and part of the outer surface of the rubber tube can be squeezed and contacted with the inner wall and bottom surface of the groove.

10. The downhole packer according to claim 2, characterized in that, The inner surface of the sealing ring is provided with multiple protrusions. When the rubber tube is compressed in the axial direction, part of the rubber tube can enter the concave area between each of the protrusions, and part of the outer surface of the rubber tube can be pressed into contact with the concave area and the side surface of each of the protrusions.

11. The downhole packer according to claim 2, characterized in that, The inner surface of the sealing ring is provided with multiple protrusions and multiple grooves. When the rubber tube is compressed in the axial direction, part of the rubber tube can enter between each of the protrusions and inside the grooves. Part of the outer surface of the rubber tube can be pressed into contact with the surface between the protrusions, the inner wall of the groove and the bottom surface.

12. The downhole packer according to claim 9, characterized in that, The groove extends circumferentially on the inner surface of the sealed pipe section.

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