Elastomer expansion packer self-adaptive to well diameter and using method
By using an adaptive wellbore caliber elastomeric expandable packer, and by incorporating adjustment and buffer components, the problems of narrow packer application range and axial tension of the packer sleeve have been solved, thus improving applicability and durability for larger wellbore diameters.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-09
- Publication Date
- 2026-04-14
AI Technical Summary
Existing packers have a narrow range of applications and poor versatility, which can easily lead to low construction efficiency. At the same time, the rubber sleeve generates axial tension under external pressure, which can easily cause excessive stress on the connection parts and structural fatigue.
An adaptive wellbore caliber elastomeric expansion packer was designed. Through the combined use of adjustment and buffer components, the packer achieves adaptive expansion and buffering of the packer. The packer includes a combination of sliding sleeve, slider, gear and screw, which utilizes hydraulic pressure and rotational motion to convert into axial displacement, thereby enhancing the adaptability and durability of the packer.
It improves the packer's applicability to larger well diameters, reduces hydraulic expansion time, enhances the cushioning effect of the packer, and improves construction efficiency and structural durability.
Smart Images
Figure CN121853969A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of packer technology, and in particular to an adaptive wellbore caliber elastomeric expansion packer and its usage method. Background Technology
[0002] Elastomer expandable packers are downhole packing tools widely used in oil and gas well completion, workover, testing, and production enhancement operations. Traditional expandable packers generally use hydraulic setting, which mainly relies on pumping high-pressure fluid into the central tube or inner cavity of the packer. The fluid pressure pushes the packer outward to fit tightly against the inner wall of the casing, thereby completing the annular seal.
[0003] However, in actual downhole operations, existing packers are often designed for a single well diameter, resulting in a narrow range of applications and poor versatility. When encountering well diameters that are too large in the field, the original packers are prone to insufficient expansion of the rubber sleeve and inability to effectively seal against the well wall. In this case, it is necessary to replace the packer with one of the corresponding specifications and run it down into the well again, which increases the construction process and time, resulting in low construction efficiency. On the other hand, after the packer has completed sealing and is put into operation, the outer wall of the rubber sleeve is continuously subjected to the external pressure formed by high-pressure fluids such as oil, gas, and water in the well. Under the combined action of external pressure and the elastic recoil force of the rubber sleeve itself, the rubber sleeve will have an axial contraction tendency, which will generate axial tension on the lower inner support core and the lower connector. Especially in the case of larger well diameters, the greater the radial expansion of the rubber sleeve, the greater the axial tension generated on the lower inner support vulcanized core under the combined action of its elastic contraction tendency and the external fluid pressure. This will increase the axial tension acting on the lower inner support vulcanized core and the lower connector, which can easily cause problems such as excessive stress on the connection and structural fatigue.
[0004] Therefore, this application provides an adaptive wellbore caliber elastomeric expansion packer and its usage method to meet the requirements. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide an adaptive wellbore caliber elastomeric expansion packer and its usage method, so as to solve the problems of the narrow application range and poor versatility of the existing packers, which easily leads to low construction efficiency. At the same time, the rubber sleeve will generate axial tensile force under external pressure, which can easily cause excessive stress on the connection parts or even structural fatigue.
[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: An adaptive wellbore caliber elastomeric expansion packer includes two fixed seats. Each of the upper and lower fixed seats has an inner support core that slides within it. A rubber sleeve is threadedly and sealingly connected between the outer sides of the two inner support cores. A connecting pipe is fixedly installed in the through hole at the center of each inner support core. A central tube is rotatably connected to the inner side of the connecting pipe. An upper connector is installed on the top of the upper fixed seat, and the top of the central tube is installed inside the upper connector. Two symmetrical sliding grooves are formed on the inner sidewall of the lower fixed seat, and a lower connector is located inside the lower fixed seat. An adjustment assembly is provided between the connecting pipe and the central tube for adjusting the position between the two inner support cores. A buffer assembly is provided between the sliding grooves and the lower connector for buffering the lower inner support core and rubber sleeve when subjected to pressure impact.
[0007] Optionally, the adjusting component includes a sliding sleeve with a groove on its inner side, the groove slidingly engaging with a protrusion on the outer side of the central tube, a slider 1 installed inside the sliding sleeve, the slider 1 slidingly engaging with a spiral groove on the outer side of the connecting tube, and multiple strip blocks fixedly installed at equal angles in the circumferential direction inside the upper inner support core, the strip blocks slidingly engaging with strip grooves at equal angles in the circumferential direction on the outer side of the connecting tube.
[0008] Optionally, the shape of the slider corresponds to the spiral groove structure on the outside of the connecting pipe, and the positions of the multiple strip grooves on the outside of the connecting pipe correspond to the positions of the multiple strip blocks.
[0009] Optionally, the lower section of the connecting pipe is sealed and slidably connected to the lower connector via a slider one. A sealing plate two is fixedly connected inside the lower connector. Multiple circular water outlets are opened at the bottom end of the central pipe. Multiple water inlets one are opened circumferentially at the bottom end of the sealing plate one. Multiple water inlets two are opened circumferentially at the top end of the lower connector. Multiple water inlets three are opened circumferentially on the outer side of the lower inner support core.
[0010] Optionally, the first, second, and third water inlets are aligned axially, forming a continuous axial water inlet channel to guide the liquid from the central tube to the annular space between the rubber sleeve and the connecting pipe.
[0011] Optionally, a connecting sleeve is fixed to the outer side of the lower end protrusion of the inner support core described below, and an annular groove is opened at the top of the lower connector, with the connecting sleeve slidingly engaging with the annular groove vertically.
[0012] Optionally, the buffer assembly includes a gear one and two connecting blocks. The gear one is fixedly installed at the bottom end of the central tube by an internal connecting column. The connecting column rotates through the sealing plate two. The gear one has two gears two meshing symmetrically. A screw is fixedly connected to the center of each of the two gears two. The two screws are rotatably connected to the inside of two sliding grooves. A slider two is threadedly connected to the outside of each of the two screws. The two connecting blocks are symmetrically installed on the outside of the lower connector. The two sliders two and the two connecting blocks are limited to slide within the two sliding grooves. The connecting blocks and sliders two are connected by a spring. The connecting blocks are slidably sleeved on the outside of the screws.
[0013] Optionally, the method includes the following steps: S1: Connect the packer to the downhole tubing string via the upper and lower connectors, and lower it into the target well section with the tubing string. At this time, the packer is in a natural contraction state, achieving safe lowering. S2: After the packer is in place, the central tube is rotated to drive the sliding sleeve to rotate. The sliding sleeve moves axially downward under the action of the spiral groove, pushing the inner support core located above to move downward, causing the rubber sleeve to expand radially, and achieving adaptive adjustment of a larger well diameter within a certain range. S3: The rotation of the central tube drives the movement of gear one, gear two and screw to adjust the axial height of slider two, move slider two upward to expand the spring buffer stroke and improve the buffering effect; S4: Pump liquid into the central tube, and it enters the annular gap between the rubber sleeve and the connecting pipe through the chamber formed by sealing plate one and sealing plate two, water inlet one, water inlet two and water inlet three. Under the action of pressure difference, the rubber sleeve expands further radially and fits against the inner wall of the well barrel to achieve a reliable seal.
[0014] Compared with the prior art, the present invention has at least the following beneficial effects: In the above scheme, by setting an adjustment component, during the synchronous rotation of the sliding sleeve driven by the rotating central tube, the slider inside the sliding sleeve slides along the spiral groove on the outside of the connecting pipe. Under the spiral guidance, the rotational motion is converted into the axial downward movement of the sliding sleeve. The downward movement of the sliding sleeve pushes the upper inner support core downward, reducing the distance between the two inner support cores and applying axial compression to the rubber sleeve, causing the rubber sleeve to expand radially, thereby adapting to a larger well diameter within a certain range. At the same time, it reduces the fluid filling time required for subsequent hydraulic expansion and improves the applicability of the packer for use in a larger well diameter within a certain range.
[0015] In the above scheme, the buffer assembly, under the action of the spring between the connecting block and the second slider, facilitates the absorption of impact and tension. The rotation of the central tube drives the first gear to rotate, thereby driving the two second gears to rotate synchronously in opposite directions, causing the screw to rotate, and thus adjusting the axial position of the second slider in the groove, changing its distance from the connecting block, so as to increase the spring buffer stroke. The larger the well diameter, the greater the initial expansion of the rubber sleeve driven by the adjustment assembly. At this time, the second slider is moved higher, further expanding the buffer stroke, improving the buffering effect, and improving the structural durability of the lower connector, inner support core and rubber sleeve in high pressure and large diameter wells. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the overall internal structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the overall internal structure of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the overall external structure of the present invention; Figure 4 This is a schematic diagram of the adjustment component structure of the present invention; Figure 5 This is a schematic diagram of the sliding sleeve and connecting pipe structure of the present invention; Figure 6 This is a schematic diagram of the overall lower structure of the present invention; Figure 7 For the present invention Figure 6 Enlarged schematic diagram of the structure at point A in the middle; Figure 8 For the present invention Figure 6 Enlarged schematic diagram of the structure at point B; Figure 9 This is a schematic diagram showing the disassembled lower fixing base and lower connector of the present invention; Figure 10 This is a schematic diagram of the internal structure of the connector of the present invention; Figure 11 This is a schematic diagram of the disassembled structure of the lower inner support core, connecting sleeve, and lower connector of the present invention; Figure 12 This is a schematic diagram of the disassembled structure of the connecting tube, central tube, and sealing plate of the present invention.
[0017] In the diagram: 1. Fixed base; 11. Slide groove; 2. Inner support core; 3. Rubber tube; 4. Connecting pipe; 5. Central tube; 6. Upper connector; 7. Lower connector; 71. Sealing plate one; 72. Sealing plate two; 8. Adjusting assembly; 81. Sliding sleeve; 82. Sliding block one; 83. Strip block; 9. Buffer assembly; 91. Gear one; 92. Gear two; 93. Screw; 94. Sliding block two; 95. Connecting block; 10. Connecting sleeve. Detailed Implementation
[0018] To further illustrate the technical means and effects adopted by the present invention in order to achieve the intended purpose, the following detailed description is provided in conjunction with the accompanying drawings and preferred embodiments, based on the specific implementation methods, structures, features and effects of the present invention.
[0019] Please see Figures 1 to 12 This invention provides a technical solution: an adaptive wellbore caliber elastomeric expansion packer, comprising two fixed seats 1, with inner support cores 2 slidingly limited inside each of the upper and lower fixed seats 1, and a rubber sleeve 3 threadedly and sealingly connected between the outer sides of the two inner support cores 2. A connecting pipe 4 is fixedly installed in the through hole at the center of the two inner support cores 2, and a central pipe 5 is rotatably connected to the inner side of the connecting pipe 4. An upper connector 6 is installed on the top of the upper fixed seat 1, and the top of the central pipe 5 is installed inside the upper connector 6. Two sliding grooves 11 are symmetrically opened on the inner side wall of the lower fixed seat 1, and a lower connector 7 is provided inside the lower fixed seat 1. An adjustment component 8 is provided between the connecting pipe 4 and the central pipe 5, and the adjustment component 8 is used to adjust the position between the two inner support cores 2. A buffer component 9 is provided between the sliding grooves 11 and the lower connector 7, and the buffer component 9 is used to buffer the lower inner support core 2 and the rubber sleeve 3 when subjected to pressure impact. The packer is connected to the tubing string through the upper connector 6 and the lower connector 7, and is lowered into the target well section with the tubing string. At this time, the rubber sleeve 3 is in an unexpanded state, with a small overall outer diameter, which facilitates passage through the variable diameter well section.
[0020] The adjusting assembly 8 includes a sliding sleeve 81. A groove is formed on the inner side of the sliding sleeve 81, which slides in engagement with a protrusion on the outer side of the central tube 5. A slider 82 is installed inside the sliding sleeve 81, and the slider 82 slides in engagement with a spiral groove on the outer side of the connecting tube 4. Multiple strip blocks 83 are fixedly installed at equal angles circumferentially inside the upper inner support core 2. These strip blocks 83 slide in engagement with the strip grooves at equal angles circumferentially on the outer side of the connecting tube 4. Before the packer is lowered into the wellbore, the rubber sleeve 3 is in a freely contracted state, with its overall outer diameter at its smallest, facilitating passage through narrow or variable-diameter well sections. A rotational torque is applied to the central tube 5 from the surface via the tubing string, causing it to rotate around its own axis. The protrusion on the outer side of the central tube 5 embeds into the groove on the inner wall of the sliding sleeve 81, causing the sliding sleeve 81 to rotate synchronously. The slider 82 inside the sliding sleeve 81 slides in engagement with the spiral groove on the outer side of the connecting tube 4. With the spiral groove engagement, as the sliding sleeve 81 rotates, the slider 82 moves along the spiral groove trajectory, converting the rotational motion into the axial downward displacement of the sliding sleeve 81. After the sliding sleeve 81 descends, it directly presses against the upper inner support core 2, pushing the upper inner support core 2 downward. The strip block 83 embedded in the upper inner support core 2 slides and engages with the axial strip groove on the outer wall of the connecting pipe 4, ensuring that the upper inner support core 2 can only move axially and cannot rotate with the sliding sleeve 81 or the central pipe 5, thus avoiding damage to the rubber sleeve 3 due to torsion. As the upper inner support core 2 continues to descend, the distance between the two inner support cores 2 shortens, applying an axial compressive force to the middle rubber sleeve 3. At this time, the rubber sleeve 3 undergoes radial expansion, expanding outward by a certain distance. This improves the applicability of the packer in use with larger well diameters within a certain range.
[0021] The shape of slider 82 corresponds to the spiral groove structure on the outside of connecting pipe 4. The positions of multiple strip grooves on the outside of connecting pipe 4 correspond to the positions of multiple strip blocks 83. When the sliding sleeve 81 moves downward to push the inner support core 2, multiple strip blocks 83 slide simultaneously in their respective strip grooves. Multi-point constraint enhances the guiding rigidity.
[0022] The lower section of the connecting pipe 4 is sealed and slidably fitted to the lower connector 7 via a slider 82. A sealing plate 72 is fixedly connected inside the lower connector 7. Multiple circular outlets are located at the bottom of the central pipe 5. Multiple inlets are located circumferentially at the bottom of the sealing plate 71. Multiple inlets are located circumferentially at the top of the lower connector 7. Multiple inlets are located circumferentially on the outer side of the lower inner support core 2. When liquid is injected into the central pipe 5, it is discharged through the circular outlets into the cavity formed by the sealing plates 71 and 72, and flows sequentially through inlets 1, 2, and 3 into the annular gap between the rubber sleeve 3 and the connecting pipe 4. This applies radial hydraulic pressure to the rubber sleeve 3, causing it to expand radially and thus tightly adhere to the inner wall of the wellbore. Inlet 1, Inlet 2 and Inlet 3 are aligned axially and together form a continuous axial water inlet channel to guide the liquid from the central tube 5 to the annular space between the rubber sleeve 3 and the connecting pipe 4.
[0023] The lower inner support core 2 has a connecting sleeve 10 fixed on the outer side of the protrusion at the lower end. The top of the lower connector 7 has an annular groove. The connecting sleeve 10 and the annular groove slide vertically together. When liquid is injected into the center tube 5, the liquid generates a certain downward pressure. At this time, the sliding fit between the connecting sleeve 10 and the annular groove facilitates the response to the downward thrust during hydraulic setting and also facilitates the absorption of the upward pull caused by well pressure fluctuations.
[0024] The buffer assembly 9 includes a gear 91 and two connecting blocks 95. The gear 91 is fixedly installed at the bottom of the central tube 5 via an internal connecting post. The connecting post rotates through the sealing plate 72. The teeth of the gear 91 are symmetrically engaged with two gears 92. A screw 93 is fixedly connected to the center of each gear 92. The two screws 93 are rotatably connected inside two slide grooves 11. A slider 94 is threaded to the outside of each screw 93. The two connecting blocks 95 are symmetrically installed on the outside of the lower connector 7. The two sliders 94 and the two connecting blocks 95 are all limited and slide within the two slide grooves 11. The connecting blocks 95 and the sliders 94 are connected by a spring. The connecting blocks 95 are slidably sleeved on the outside of the screws 93. When the central tube 5 rotates, it drives the gear 91 to rotate, thereby driving the two gears 92 to rotate. 92 rotates synchronously in opposite directions, causing the two screws 93 to rotate synchronously, thereby adjusting the axial position of slider 2 94 in the slide groove 11, so as to change the distance between slider 2 94 and connecting block 95, which is used to adjust the effective buffer stroke of the spring. That is, when the rubber sleeve 3 expands radially and seals inside the well barrel, its outer wall is subjected to the annular external pressure formed by fluids such as oil, water and gas inside the well barrel, causing the rubber sleeve 3 to have an axial retraction tendency, thereby forming an axial tension on the inner support core 2 located below. When the well diameter is larger, the radial expansion of the rubber sleeve 3 is greater. Under the combined action of its elastic contraction tendency and fluid external pressure, the axial tension generated on the inner support core 2 below is greater. At this time, the screw 93 is driven to rotate by gear 1 91 and gear 2 92, moving slider 2 94 upward to expand the buffer stroke of the spring and improve the buffering effect.
[0025] As one embodiment of the present invention, the method includes the following steps: S1: Connect the packer to the downhole tubing string via the upper connector 6 and the lower connector 7, and lower it into the target well section with the tubing string. At this time, the rubber sleeve 3 is in a natural contraction state, achieving safe lowering. S2: After the packer is in place, rotate the central tube 5 to drive the sliding sleeve 81 to rotate. The sliding sleeve 81 moves axially downward under the action of the spiral groove, pushing the inner support core 2 located above to move downward, causing the rubber sleeve 3 to expand radially, and achieving adaptive adjustment of a larger well diameter within a certain range. S3: The rotation of the central tube 5 drives the gear 1 91, gear 2 92 and screw 93 to move, so as to adjust the axial height of the slider 2 94, move the slider 2 94 upward to expand the spring buffer stroke and improve the buffering effect; S4: Pump liquid into the central tube 5, and enter the annular gap between the rubber sleeve 3 and the connecting pipe 4 through the chamber formed by sealing plate 1 71 and sealing plate 2 72, water inlet 1, water inlet 2 and water inlet 3. Under the action of pressure difference, the rubber sleeve 3 further expands radially and fits against the inner wall of the well barrel to achieve a reliable seal.
[0026] The working principle of the technical solution provided by this invention is as follows: The packer is connected to the downhole tubing via the upper connector 6 and the lower connector 7 and is lowered into the target well section. At this time, the distance between the two inner support cores 2 is the largest, the rubber sleeve 3 is in a natural contraction state, and the overall outer diameter is the smallest, which facilitates smooth passage through the well section and achieves safe lowering. After the packer reaches the predetermined position, a rotational torque is applied to the central tube 5 through the tubing string, causing the central tube 5 to rotate around its own axis. The protrusion on the outside of the central tube 5 cooperates with the groove on the inside of the sliding sleeve 81, driving the sliding sleeve 81 to rotate synchronously. The slider 82 inside the sliding sleeve 81 slides along the spiral groove on the outside of the connecting pipe 4. Under the spiral guidance, the rotational motion is converted into the axial downward movement of the sliding sleeve 81. The sliding sleeve 81 moves downward and presses against the inner support core 2 located above, pushing the inner support core 2 above to move downward. The inner support core 2 above is limited by the inner strip block 83 and the strip groove on the outside of the connecting pipe 4, and only makes axial translation. The downward movement of the inner support core 2 above reduces the distance between the upper and lower inner support cores 2, thereby forming an axial compression on the rubber sleeve 3, causing the rubber sleeve 3 to expand radially outward, improving the applicability of the packer in the process of using larger well diameters within a certain range. When the packer is sealing, the outer wall of the rubber sleeve 3 is subjected to external pressure from fluids such as oil, water, and gas inside the wellbore, causing the rubber sleeve 3 to tend to retract axially. This, in turn, creates an axial tensile force on the lower inner support core 2 and the lower connector 7. This tensile force is transmitted to the connecting block 95 through the lower connector 7. Under the action of the spring between the connecting block 95 and the second slider 94, the impact and tensile force are easily absorbed, preventing the lower connector 7 from being damaged by rigid impact. Furthermore, when the central tube 5 rotates, it drives the first gear 91 to rotate, which in turn drives the two second gears 92 to rotate synchronously in opposite directions, causing the two... The screw 93 rotates synchronously, thereby adjusting the axial position of the second slider 94 in the groove 11, so as to change the distance between the second slider 94 and the connecting block 95, which is used to increase the effective buffer stroke of the spring. That is, when the well diameter is larger, the radial expansion of the rubber sleeve 3 is greater. Under the combined action of its elastic contraction tendency and the external fluid pressure, the axial tension generated on the lower inner support core 2 is greater. At this time, the screw 93 is driven to rotate through the gear 1 91 and the gear 2 92, which moves the second slider 94 upward, so as to expand the buffer stroke of the spring and improve the buffering effect. After adjustment, liquid is pumped into the center tube 5. The liquid flows out from the outlet at the bottom of the center tube 5 and enters the chamber formed by sealing plate 1 71 and sealing plate 2 72. The liquid passes through the through axial water inlet channel composed of inlet 1, inlet 2 and inlet 3 in sequence and enters the annular gap between the rubber sleeve 3 and the connecting pipe 4. At this time, under the action of pressure difference, the rubber sleeve 3 expands further radially and fits tightly against the inner wall of the well barrel to achieve a reliable seal. When unsealing is required, stop supplying liquid to the central tube 5, release the internal hydraulic pressure of the rubber tube 3, and cause the rubber tube 3 to shrink and reset. By adjusting the component 8, the sliding sleeve 81 is driven to move upward, releasing the squeezing force on the upper inner support core 2, so that the distance between the two inner support cores 2 returns to the initial position. The rubber tube 3 shrinks radially under its own elasticity and returns to the initial state.
[0027] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. An adaptive wellbore caliber elastomeric expansion packer, comprising two fixed seats (1), characterized in that, Both upper and lower fixed seats (1) have inner support cores (2) that slide within them. A rubber sleeve (3) is threaded and sealed between the outer sides of the two inner support cores (2). A connecting pipe (4) is fixedly installed in the through hole at the center of the two inner support cores (2). A central pipe (5) is rotatably connected to the inner side of the connecting pipe (4). An upper connector (6) is installed on the top of the upper fixed seat (1). The top of the central pipe (5) is installed inside the upper connector (6). Two sliding grooves (11) are symmetrically opened on the inner side wall of the lower fixed seat (1). A lower connector (7) is provided inside the lower fixed seat (1). An adjustment component (8) is provided between the connecting pipe (4) and the central pipe (5). The adjustment component (8) is used to adjust the position between the two inner support cores (2). A buffer component (9) is provided between the sliding groove (11) and the lower connector (7). The buffer component (9) is used to buffer the lower inner support core (2) and the rubber sleeve (3) when subjected to pressure impact.
2. The adaptive wellbore caliber elastomeric expansion packer according to claim 1, characterized in that, The adjustment component (8) includes a sliding sleeve (81), the inner side of which is provided with a groove, the groove slidingly engaging with the protrusion on the outer side of the central tube (5), a slider (82) is installed inside the sliding sleeve (81), the slider (82) slidingly engaging with the spiral groove on the outer side of the connecting tube (4), and multiple strip blocks (83) are fixedly installed at equal angles in the circumferential direction inside the inner support core (2) above, the strip blocks (83) slidingly engaging with the strip groove on the outer side of the connecting tube (4) at equal angles in the circumferential direction.
3. The adaptive wellbore caliber elastomeric expansion packer according to claim 2, characterized in that, The shape of the slider (82) corresponds to the spiral groove structure on the outside of the connecting pipe (4), and the positions of the multiple strip grooves on the outside of the connecting pipe (4) correspond to the positions of the multiple strip blocks (83).
4. The adaptive wellbore caliber elastomeric expansion packer according to claim 1, characterized in that, The lower section of the connecting pipe (4) is sealed and slidably connected to the lower connector (7) via a slider (82). The lower connector (7) is fixedly connected to a sealing plate (72). The bottom end of the central pipe (5) has multiple circular water outlets. The bottom end of the sealing plate (71) has multiple water inlets. The top end of the lower connector (7) has multiple water inlets. The outer side of the inner support core (2) below has multiple water inlets.
5. The adaptive wellbore caliber elastomeric expansion packer according to claim 4, characterized in that, The three inlets are aligned axially and together form a continuous axial water inlet channel to guide the liquid from the central tube (5) to the annular space between the rubber tube (3) and the connecting tube (4).
6. The adaptive wellbore caliber elastomeric expansion packer according to claim 1, characterized in that, The lower end of the inner support core (2) is fixed with a connecting sleeve (10) on the outer side of the protrusion. The top of the lower connector (7) is provided with an annular groove, and the connecting sleeve (10) slides vertically with the annular groove.
7. The adaptive wellbore caliber elastomeric expansion packer according to claim 4, characterized in that, The buffer assembly (9) includes a gear (91) and two connecting blocks (95). The gear (91) is fixedly installed at the bottom of the central tube (5) by an internal connecting column. The connecting column is sealed and rotates through the sealing plate (72). The gear (91) has two gears (92) symmetrically meshing with each other. A screw (93) is fixedly connected to the center of each of the two gears (92). The two screws (93) are rotatably connected inside the two slide grooves (11). A slider (94) is threadedly connected to the outside of each of the two screws (93). The two connecting blocks (95) are symmetrically installed outside the lower connector (7). The two sliders (94) and the two connecting blocks (95) are limited to slide inside the two slide grooves (11). The connecting blocks (95) and the sliders (94) are connected by a spring. The connecting blocks (95) are slidably sleeved on the outside of the screws (93).
8. A method of using an adaptive wellbore caliber elastomeric expandable packer, applicable to the adaptive wellbore caliber elastomeric expandable packer as described in any one of claims 1-7, characterized in that: The method includes the following steps: S1: Connect the packer to the downhole tubing through the upper connector (6) and the lower connector (7), and lower it into the target well section. At this time, the rubber sleeve (3) is in a natural contraction state, so as to achieve safe lowering. S2: After the packer is in place, rotate the central tube (5) to drive the sliding sleeve (81) to rotate. The sliding sleeve (81) moves axially downward under the action of the spiral groove, pushing the inner support core (2) located above to move downward, so that the rubber sleeve (3) expands radially, and realizes adaptive adjustment of a larger well diameter within a certain range. S3: The rotation of the central tube (5) drives the gear one (91), gear two (92) and screw (93) to move, so as to adjust the axial height of the slider two (94), move the slider two (94) upward to expand the spring buffer stroke and improve the buffering effect; S4: Pump liquid into the central tube (5), and enter the annular gap between the rubber tube (3) and the connecting pipe (4) through the chamber formed by sealing plate one (71) and sealing plate two (72), water inlet one, water inlet two and water inlet three. Under the action of pressure difference, the rubber tube (3) expands further radially and fits against the inner wall of the well barrel to achieve a reliable seal.