High temperature and high pressure cutting retrievable packer

Abstract

The application discloses a high-temperature and high-pressure cutting recyclable packer. The packer comprises an upper joint, an upper mandrel, a lower mandrel and a lower joint which are sequentially screwed from top to bottom, and further comprises an upper anchoring mechanism which is arranged on the upper middle part of the upper mandrel, a rubber sleeve sealing mechanism which is arranged on the middle part of the upper mandrel, a lower anchoring mechanism which is arranged on the lower middle part of the upper mandrel, a lower slip retreat-stop mechanism which is arranged between the upper mandrel and the lower anchoring mechanism, a setting mechanism which is arranged on the outer periphery of the lower part of the upper mandrel and the lower mandrel, a locking mechanism which is arranged on the outer periphery of the setting mechanism and a releasing mechanism which is arranged on the middle part of the lower mandrel. The packer has the advantages of reliable sealing in a high-temperature and high-pressure environment and high recycling efficiency of the recyclable packer.

Description

Technical Field

[0001] This invention relates to the field of oil and gas development and completion technology, and in particular to a high-temperature, high-pressure cutting and recyclable packer. Background Technology

[0002] Packers are one of the core downhole tools in oil and gas well engineering technology. Their core function is to isolate different sections within the wellbore, thereby enabling targeted operations on the target producing layer. As oil and gas exploration and development both domestically and internationally moves towards deeper and ultra-deeper layers, the downhole environment is becoming increasingly harsh, characterized by high temperature, high pressure, and high corrosiveness. This places extremely high demands on packer performance. In existing technologies, reusable packers are widely used due to their reusability and relatively low operating costs. However, in the high-temperature and high-pressure environments of deep and ultra-deep wells, traditional reusable packers have revealed several technical challenges that urgently need to be addressed. Insufficient reliability of setting and unsealing: Conventional reusable packers mostly use mechanical or hydraulic setting, relying on slip anchoring and expansion of the rubber sleeve sealing mechanism to achieve a seal. Under ultra-high pressure conditions, the pressure difference between the top and bottom of the packer is enormous, which can easily cause the unsealing mechanism to "lock up" or the slips to embed too deeply into the casing, resulting in difficulty or even inability to unseal. This requires complex milling and grinding operations, which are not only extremely costly but also pose a significant risk of damaging the production casing. Limited temperature and pressure resistance: Traditional packers' sealing sleeves and structural components are prone to aging, hardening, or strength reduction under long-term high-temperature environments, leading to seal failure. Furthermore, their overall structural design may not withstand extremely high annular pressure and tubing internal pressure, posing a risk of structural instability or leakage. Insufficient anchoring performance: Conventional retrievable packers use a cage-type slip structure. After the slips open, the contact area with the casing is small, and the engagement depth is shallow. Under pressure differentials, slip slip slipping and unstable anchoring can easily occur, even causing tubing displacement and seal failure.

[0003] To resolve the contradiction between "recyclability" and "high pressure resistance," the field urgently needs an innovative packer design that can meet the long-term reliable sealing requirements of deep and ultra-deep wells under high temperature and high pressure environments, while also enabling rapid, safe, and unrecoverable unsealing after operation without relying on enormous mechanical pulling force, thereby significantly reducing operational risks and costs. This newly designed high-temperature, high-pressure cutting and recyclable packer perfectly solves these problems. It possesses both the high-temperature, high-pressure sealing reliability of permanent packers and the high-efficiency recyclability of recyclable packers. This packer is particularly suitable for the exploitation of deep and ultra-deep wells and high-temperature, high-pressure oil and gas reservoirs, achieving reliable interlayer sealing under extreme conditions and complete recovery after operation, possessing significant economic and environmental value. Summary of the Invention

[0004] The purpose of this invention is to provide a high-temperature and high-pressure cutting and recyclable packer that can meet the sealing reliability requirements of high-temperature and high-pressure environments, and also has the high recyclability of a recyclable packer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution, comprising an upper connector, an upper mandrel, a lower mandrel, and a lower connector that are threaded together from top to bottom, and further comprising: The upper anchoring mechanism is covered in the upper middle part of the upper mandrel and is used to open radially during setting and anchor to the sleeve. A rubber sleeve sealing mechanism, which covers the middle of the upper mandrel, is used to seal the annulus between the oil pipe and the casing during setting; The lower anchoring mechanism is covered in the lower middle part of the upper mandrel and is used to open radially during setting and anchor to the sleeve. The lower locking mechanism is located between the upper mandrel and the lower anchoring mechanism to prevent the lower anchoring mechanism from opening accidentally during unsealing. A setting mechanism, which covers the lower part of the upper mandrel and the outer periphery of the lower mandrel, is used to drive the upper anchoring mechanism, the rubber sleeve sealing mechanism and the lower anchoring mechanism to set. A locking mechanism, which covers the outer periphery of the setting mechanism, is used to prevent the rubber sleeve sealing mechanism from retracting after setting. An unsealing mechanism is provided in the middle of the lower mandrel for cutting the lower mandrel and unlocking the sealing mechanism; The setting mechanism includes an upper piston, an upper piston sleeve, a lower piston, and a lower piston sleeve; the upper piston covers the lower outer periphery of the upper mandrel, and the upper piston sleeve covers the lower outer periphery of the upper piston; the lower end of the upper piston is sealed to the upper piston sleeve and the upper mandrel respectively; the upper outer periphery of the lower mandrel is sealed to the upper piston sleeve; a first piston cavity is formed between the upper piston, the upper piston sleeve, the lower mandrel, and the upper mandrel; a radial first pressure transmission hole is provided on the lower part of the upper mandrel corresponding to the first piston cavity; the upper piston and the upper piston sleeve are threaded together and then connected by a first fixing pin; the upper mandrel and the lower mandrel are threaded together... The components are connected by a threaded joint and a first fixing pin; the lower piston cover is disposed on the outer periphery of the middle part of the lower mandrel, and the lower piston sleeve is disposed on the outer periphery of the lower part of the lower piston; the lower end of the lower piston is sealed to the lower piston sleeve and the lower mandrel; the outer periphery of the upper end of the lower connector is sealed to the lower piston sleeve; a second piston cavity is formed between the lower piston, the lower piston sleeve, the lower connector, and the lower mandrel, and a radial second pressure transmission hole is provided on the lower part of the lower mandrel at a position corresponding to the second piston cavity; the upper end of the lower piston is connected to the lower end of the upper piston sleeve by a first fixing pin; the lower end of the lower piston sleeve is connected to the upper end of the lower connector by a second fixing pin.

[0006] Preferably, the upper anchoring mechanism includes an upper gauge ring, an upper slip cage, six upper slips, and an upper cone. The upper gauge ring is mounted on the upper part of the upper mandrel. Fixing screws pass through the upper gauge ring and are inserted into the sliding track groove of the upper mandrel to prevent rotation. The internal reduction in diameter of the upper gauge ring is used to abut against the positioning step of the upper mandrel when the packer is lifted, releasing part of the release distance and facilitating smooth release of the packer. The upper slip cage is set on the positioning step of the upper mandrel and threadedly connected to the upper gauge ring, and fixedly connected to the shear pin of the upper mandrel. Six upper slips are evenly distributed along the circumference of the lower outer periphery of the upper slip cage. A first T-shaped groove; six first conical track grooves are evenly distributed around the outer circumference of the upper part of the upper cone; a first T-shaped block adapted to the first T-shaped groove is provided on the upper part of the upper clamping plate, and a first sliding lug adapted to the first conical track groove is provided on the lower part of the upper clamping plate; multiple clamping plate tooth grooves are provided on the upper end face of the upper clamping plate, and a first inclined plane adapted to the bottom of the first conical track groove is provided on the lower end face of the upper clamping plate; the upper clamping plate is connected to the upper mandrel by shear bolts; the upper cone is connected to the upper mandrel by first shear pins.

[0007] Preferably, the length of the six first T-shaped grooves gradually increases along the circumferential direction, which facilitates the step-by-step forced recovery of the upper slip; a first limiting step is provided on both sides of the base of the first T-shaped block; a first limiting groove adapted to the first limiting step is provided at the base of the first T-shaped groove; the length of the first limiting step is 40-45mm.

[0008] Preferably, the rubber sleeve sealing mechanism is composed of a support ring, a shoulder, a triangular ring, a protective ring, a side rubber sleeve, a spacer ring, a middle rubber sleeve, a spacer ring, a side rubber sleeve, a protective ring, a triangular ring, a shoulder, and a support ring from top to bottom; the side rubber sleeve and the middle rubber sleeve are made of modified fluororubber; the support ring and the shoulder are made of 20# steel; the protective ring is made of polytetrafluoroethylene; and the spacer ring is made of 42CrMo alloy steel.

[0009] Preferably, the lower anchoring mechanism consists of a lower cone, a lower slip, and a lower slip cage arranged sequentially from top to bottom; six second conical track grooves are evenly distributed along the circumference of the lower outer periphery of the lower cone; six second T-shaped grooves are evenly distributed along the circumference of the upper outer periphery of the lower slip cage; a second T-shaped block adapted to the second T-shaped groove is provided at the lower part of the lower slip, and a second sliding lug adapted to the second conical track groove is provided at the lower part of the lower slip; multiple slip tooth grooves are provided on the upper end face of the lower slip; a second inclined plane adapted to the bottom of the second conical track groove is provided on the lower end face of the lower slip; a push sleeve is provided between the inner periphery of the lower slip and the outer periphery of the upper mandrel, the upper end of the push sleeve is threadedly connected to the lower cone, the lower end of the push sleeve is connected to the lower slip cage by a second shear pin, and the lower slip cage is connected to the upper piston by a third shear pin.

[0010] Preferably, a second limiting step is provided on both sides of the base of the second T-shaped block; a second limiting groove adapted to the second limiting step is provided at the base of the second T-shaped groove; the length of the second limiting step is 15-20mm.

[0011] Preferably, the lower end of the push sleeve has an outwardly extending periphery, on which multiple sets of shear pin shearing holes are evenly distributed; the front end of the periphery is a straight step, which abuts against the inner end face of the lower slip cage; there are multiple second shear pins, and the number of second shear pins is used to adjust the setting pressure value applied to the rubber sleeve sealing mechanism, thereby controlling the timing of the lower slip opening.

[0012] Preferably, the lower locking mechanism consists of an upper locking ring and an upper anti-rotation screw; the upper locking ring is disposed between the lower cone and the upper mandrel; the outer and inner circumferences of the upper locking ring are respectively provided with a first locking ring tooth and a second locking ring tooth, and the inner circumference of the lower cone is provided with a first serrated thread that meshes with the first locking ring tooth; the lower middle outer circumference of the upper mandrel is provided with a first locking tooth for meshing with the second locking ring tooth during unsealing; a groove is provided on the upper locking ring, and the upper anti-rotation pin passes through the lower cone and is inserted into the groove of the upper locking ring.

[0013] Preferably, the locking mechanism includes a lower locking ring, a locking ring sleeve, and a lower anti-rotation pin; the lower locking ring covers the upper part of the lower piston, and the locking ring sleeve covers the outer periphery of the lower locking ring; the lower anti-rotation pin passes through the locking ring sleeve and is inserted into the groove of the lower locking ring; the upper end of the locking ring sleeve is connected to the lower end of the upper piston sleeve by a first shear pin; the lower end of the locking ring sleeve is connected to the upper end of the lower piston sleeve by a first fixing pin; a third locking ring tooth and a fourth locking ring tooth are respectively provided on the outer and inner peripheries of the lower locking ring, and a second serrated thread that meshes with the third locking ring tooth is provided on the inner periphery of the locking ring sleeve; a third locking tooth that matches the fourth locking ring tooth is provided on the outer periphery of the lower piston.

[0014] Preferably, the unsealing mechanism includes a pre-cut section and a through-hole ring disposed in the middle of the lower mandrel; the through-hole ring is disposed on the outer periphery of the lower connector and is connected to the lower connector by a second fixing pin.

[0015] The beneficial effects of the invention are that it can meet the sealing reliability requirements of high temperature and high pressure environments, and also has the high recyclability of a recyclable packer. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of a high-temperature, high-pressure cutting recyclable packer according to the present invention.

[0017] Figure 2 This is a cross-sectional view of the upper anchoring mechanism in this invention.

[0018] Figure 3 This is a cross-sectional view of the rubber sleeve sealing mechanism in this invention.

[0019] Figure 4 This is a cross-sectional view of the lower slip anti-reverse mechanism and the lower anchoring mechanism in this invention.

[0020] Figure 5 This is a cross-sectional view of the locking mechanism and the unlocking mechanism in this invention.

[0021] Figure 6 This is a perspective view of the upper clapper cage in this invention.

[0022] Figure 7 This is a perspective view of the upper cladding in this invention.

[0023] Figure 8 This is a three-dimensional view of the upper cone in this invention.

[0024] Figure 9 This is a perspective view of the lower cladding cage in this invention.

[0025] Figure 10 This is a perspective view of the lower cladding in this invention.

[0026] Figure 11 This is a three-dimensional view of the lower cone in this invention.

[0027] Figure 12 This is a cross-sectional view of the push sleeve in this invention. Detailed Implementation

[0028] The invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0029] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0030] like Figure 1-12 As shown, a high-temperature, high-pressure cutting and recyclable packer of the present invention includes an upper connector 1, an upper mandrel 2, a lower mandrel 15, and a lower connector 22 connected sequentially from top to bottom by threads, and further includes: The upper anchoring mechanism is covered in the upper middle part of the upper mandrel 2 and is used to open radially during setting and anchor to the sleeve. The rubber sleeve sealing mechanism 23 is installed in the middle of the upper mandrel 2 and is used to seal the annulus between the oil pipe and the casing during setting. The lower anchoring mechanism is covered in the lower middle part of the upper mandrel 2 and is used to open radially during setting and anchor to the sleeve. The lower locking mechanism is located between the upper mandrel 2 and the lower anchoring mechanism to prevent the lower anchoring mechanism from opening accidentally during unsealing. The setting mechanism, which covers the lower part of the upper mandrel 2 and the outer periphery of the lower mandrel 15, is used to drive the upper anchoring mechanism, the rubber sleeve sealing mechanism and the lower anchoring mechanism to set. A locking mechanism, which covers the outer periphery of the setting mechanism, is used to prevent the rubber sleeve sealing mechanism from retracting after setting. An unsealing mechanism is provided in the middle of the lower mandrel for cutting the lower mandrel and unlocking the sealing mechanism; The setting mechanism includes an upper piston 13, an upper piston sleeve 14, a lower piston 19, and a lower piston sleeve 20. The upper piston 13 covers the lower outer periphery of the upper mandrel 2, and the upper piston sleeve 14 covers the lower outer periphery of the upper piston 13. The lower end of the upper piston 13 is sealed to the upper piston sleeve 14 and the upper mandrel 2. The upper outer periphery of the lower mandrel 15 is sealed to the upper piston sleeve 14. A first piston chamber is formed between the upper piston 13, the upper piston sleeve 14, the lower mandrel 19, and the upper mandrel 2. A radial first pressure transmission hole 25 is provided at the lower part of the upper mandrel 2 corresponding to the first piston chamber. The upper piston 13 and the upper piston sleeve 14 are threaded together and connected by a first fixing pin A1. The upper mandrel 2 and the lower mandrel 15 are threaded together. The lower piston 19 is fitted around the middle outer periphery of the lower mandrel 15, and the lower piston sleeve 20 is fitted around the lower outer periphery of the lower piston 19. The lower end of the lower piston 19 is sealed to the lower piston sleeve 20 and the lower mandrel 15. The upper outer periphery of the lower connector 22 is sealed to the lower piston sleeve 20. A second piston chamber is formed between the lower piston 19, the lower piston sleeve 20, the lower connector 22, and the lower mandrel 15. A radial second pressure transmission hole 24 is provided on the lower part of the lower mandrel 15 corresponding to the position of the second piston chamber. The upper end of the lower piston 19 is connected to the lower end of the upper piston sleeve 14 by the first fixing pin A1. The lower end of the lower piston sleeve 20 is connected to the upper end of the lower connector 22 by the second fixing pin A2. The lower mandrel 15 and the lower connector 22 are connected by the first fixing pin A1.

[0031] In another embodiment, connecting rings 26 are provided between the upper anchoring mechanism and the rubber sleeve sealing mechanism 23, and between the rubber sleeve sealing mechanism 23 and the lower anchoring mechanism.

[0032] In another embodiment, the upper anchoring mechanism includes an upper gauge ring 27, an upper slip cage 3, six upper slips 4, and an upper cone 6. The upper gauge ring 27 covers the upper part of the upper mandrel 2. The fixing screw 27-1 passes through the upper gauge ring 27 and is inserted into the sliding track groove of the upper mandrel 2 to form an anti-rotation mechanism. The internal diameter reduction of the upper gauge ring 27 is used to abut against the positioning step of the upper mandrel 2 when the packer is lifted 32-34mm, releasing part of the release distance and facilitating the smooth release of the packer. The upper slip cage 3 is set on the positioning step of the upper mandrel 2 and threadedly connected to the upper gauge ring 27, and fixedly connected to the shear pin 3-1 of the upper mandrel 2. The lower outer circumference of the upper slip cage 3 is evenly distributed... The upper cone 6 is provided with six first T-shaped grooves 3-1; six first conical track grooves 6-1 are evenly distributed around the outer circumference of the upper part of the upper cone 6; a first T-shaped block 4-1 adapted to the first T-shaped groove is provided on the upper part of the upper slip 4, and a first sliding lug 4-2 adapted to the first conical track groove 6-1 is provided on the lower part of the upper slip 4; multiple slip tooth grooves 4-3 are provided on the upper end face of the upper slip 4, and a first inclined plane adapted to the groove bottom 6-2 of the first conical track groove 6-1 is provided on the lower end face of the upper slip 4; the upper slip 4 is connected to the upper mandrel 2 by shear bolts 5; the upper cone 6 is connected to the upper mandrel 2 by first shear pins A3. The upper anchoring mechanism can withstand an axial load of not less than 115t.

[0033] In another embodiment, the length of the six first T-shaped grooves 3-1 gradually increases along the circumferential direction, which facilitates the step-by-step forced recovery of the upper slip 4; a first limiting step 4-4 is provided on both sides of the base of the first T-shaped block 4-1; a first limiting groove 3-2 adapted to the first limiting step 4-4 is provided at the base of the first T-shaped groove 3-1; the length of the first limiting step 4-4 is 40-45mm.

[0034] In another embodiment, the rubber sleeve sealing mechanism comprises, from top to bottom, a support ring 23-1, a shoulder 23-2, a triangular ring 23-7, a retaining ring 23-3, a side rubber sleeve 23-4, a spacer ring 23-5, a middle rubber sleeve 23-6, a spacer ring 23-5, a side rubber sleeve 23-4, a retaining ring 23-3, a triangular ring 23-7, a shoulder 23-2, and a support ring 23-1; the side rubber sleeve 23-4 and the middle rubber sleeve 23-6 are made of modified fluororubber; the support ring 23-1 and the shoulder 23-2 are made of 20# steel; the retaining ring 23-3 is made of polytetrafluoroethylene; and the spacer ring 23-5 is made of 42CrMo alloy steel. Preferably, the rubber sleeve sealing mechanism effectively prevents structural instability caused by the shoulder protrusion, can withstand temperatures up to 232℃, and can withstand an annular gas sealing pressure of 105MPa.

[0035] In another embodiment, the lower anchoring mechanism comprises a lower cone 9, a lower slip 10, and a lower slip cage 12 arranged sequentially from top to bottom; six second conical track grooves 9-1 are evenly distributed along the circumference of the lower outer periphery of the lower cone 9; six second T-shaped grooves 12-1 are evenly distributed along the circumference of the upper outer periphery of the lower slip cage 12; a second T-shaped block 10-1 adapted to the second T-shaped groove 12-1 is provided at the lower part of the lower slip 10; and a second T-shaped block 10-1 adapted to the second conical track groove 12-1 is provided at the lower part of the lower slip 10. Two sliding lugs 10-2; multiple slip grooves 10-3 are provided on the upper end face of the lower slip 10; a second inclined plane is provided on the lower end face of the lower slip 10, which is adapted to the groove bottom 9-2 of the second conical track groove 9-1; a push sleeve 11 is provided between the inner circumference of the lower slip 10 and the outer circumference of the upper mandrel, the upper end of the push sleeve 11 is threaded to the lower cone 9, and the lower end of the push sleeve 11 is connected to the lower slip cage 12 through a second shear pin A5; the lower slip cage 12 is connected to the upper piston 13 through a third shear pin A4. As a preferred embodiment, the lower anchoring mechanism withstands an axial load of not less than 115t.

[0036] In another embodiment, a second limiting step 10-2 is provided on both sides of the base of the second T-shaped block 10-1; a second limiting groove 12-2 adapted to the second limiting step 10-2 is provided at the base of the second T-shaped groove 12-1; the length of the second limiting step 10-2 is 15-20mm.

[0037] Multiple sets of shear pins and shearing holes are evenly distributed around the periphery; the front end of the periphery is a straight step, which abuts against the inner end face of the lower slip cage 12; there are multiple second shear pins A5, and the number of second shear pins A5 is used to adjust the setting pressure value applied to the rubber sleeve sealing mechanism, thereby controlling the timing of the lower slip opening. In another embodiment, the lower locking mechanism consists of an upper locking ring 8 and an upper anti-rotation screw 7; the upper locking ring 8 is disposed between the lower cone 9 and the upper spindle 2; the outer and inner circumferences of the upper locking ring 8 are respectively provided with a first locking ring tooth and a second locking ring tooth, and the inner circumference of the lower cone 9 is provided with a first serrated thread that meshes with the first locking ring tooth; the lower middle outer circumference of the upper spindle 2 is provided with a first locking tooth 2-1 for meshing with the second locking ring tooth during unsealing; the upper locking ring 8 is provided with a groove, and the upper anti-rotation pin 7 passes through the lower cone 9 and is inserted into the groove of the upper locking ring 8.

[0038] In another embodiment, the locking mechanism includes a lower locking ring 18, a locking ring sleeve 16, and a lower anti-rotation pin 17; the lower locking ring 18 covers the upper part of the lower piston 19, and the locking ring sleeve 16 covers the outer periphery of the lower locking ring 18; the lower anti-rotation pin 17 passes through the locking ring sleeve 16 and is inserted into the groove of the lower locking ring 18; the upper end of the locking ring sleeve 16 is connected to the lower end of the upper piston sleeve 14 by a first shear pin A3; the lower end of the locking ring sleeve 16 is connected to the upper end of the lower piston sleeve 20 by a first fixing pin A1; a third locking ring tooth and a fourth locking ring tooth are respectively provided on the outer and inner peripheries of the lower locking ring 18, and a second serrated thread that meshes with the third locking ring tooth is provided on the inner periphery of the locking ring sleeve 16; a third locking tooth 19-1 that matches the fourth locking ring tooth is provided on the outer periphery of the lower piston 19.

[0039] In another embodiment, the unsealing mechanism includes a pre-cut section and a through-hole ring 21 disposed in the middle of the lower mandrel 15; the through-hole ring 21 covers the outer periphery of the lower connector 22 and is connected to the lower connector 22 by a second fixing pin A2.

[0040] During use, when the packer is in the assembled state, the first shear pin A3 tightly fixes the locking ring sleeve 16 to the upper piston sleeve 14. The upper piston sleeve 14 is connected to the lower piston 19 and the upper piston 13. When the internal pressure does not reach the starting pressure value, the components are relatively stationary.

[0041] During packer setting, pressure is transmitted through pressure transmission hole 25 to the first piston chamber, which consists of upper piston 13, upper piston sleeve 14, lower mandrel 15, and upper mandrel 2. Simultaneously, pressure is transmitted through pressure transmission hole 24 to the second piston chamber, which consists of lower piston 19, lower piston sleeve 20, lower connector 22, and lower mandrel 15. When the pressure exceeds the set starting pressure value, the first shear pin A3 is sheared, and the pressure causes lower piston 19, upper piston sleeve 14, and upper piston 13 to move upward. At this time, since the oil pipe thread of the packer upper connector 1 is connected to the upper tubing string, the lower thread of the upper connector is connected to the upper mandrel 2, the upper mandrel 2 is connected to the lower mandrel 15, and the lower mandrel 15 is connected to the lower connector 22, the upper mandrel 2 and the lower mandrel 15 do not move during setting. The upper piston 13 pushes the lower slip cage 12, push sleeve 11, lower slip 10, lower cone 9, and upper locking ring 8 upward together, further pushing the rubber sleeve sealing mechanism 23 to compress and move upward. When the thrust is greater than the shearing force of the first shearing pin A3 fixed on the upper mandrel 2, the first shearing pin A3 is sheared, causing the upper cone 6 to move upward and come closer to the upper slip cage 3. During this period, the shearing bolt 5 fixed on the upper mandrel 2 is sheared, and at the same time, the shearing pin 3-1 fixed on the step of the upper mandrel 2 is sheared. The upper slip cage 3 moves upward, and its inner upper end abuts against the straight step surface of the mandrel 2. This causes the upper slip 4 to open outward and be tightly anchored on the sleeve. At the same time, the lower locking ring 18 and the lower piston 19 are tightly locked, effectively ensuring that the slip and rubber sleeve sealing mechanism will not retract. Next, pressure is transmitted again through pressure transmission holes 24 and 25, continuously compressing the rubber sleeve sealing mechanism 23. The upper slip 4 continuously anchors the sleeve. When the transmitted pressure value is greater than the second shear pin A5 fixed on the push sleeve 11 and the lower slip cage 12, the second shear pin A5 is sheared. At the same time, the lower slip 10 opens and anchors on the sleeve until the rated setting pressure is reached. The upper slip 4 and the lower slip 10 are completely anchored on the sleeve, and the rubber sleeve sealing mechanism 23 is fully compressed and expanded. At this point, the packer setting is completed. The lower locking ring 18 ensures that the locking ring sleeve 16 and the lower piston 19 remain locked, effectively preventing the rubber sleeve from retracting and the slip from loosening, thus stabilizing the entire setting effect. When the packer is in the set position, if the packer is subjected to a downward axial load and axial vibration load, the load is transmitted to the lower slip 10 through the upper mandrel 2, lower cone 9, and lower slip cage 12. If it is subjected to an upward axial load and axial vibration load, the load is transmitted directly to the upper slip 4 through the upper mandrel 2, upper cone 6, and upper slip cage 3. Therefore, regardless of the type of axial load the packer is subjected to, the load is not transmitted to the rubber sleeve sealing mechanism 23.

[0042] During packer release, a specialized mechanical or electric cutting tool is inserted into the tubing. After accurate depth calibration, the lower packer mandrel 15 is cut off. At this point, the lower packer connector 22 and the tubing below it are in a movable state. The tubing is then lifted straight up, causing the upper mandrel 2 to move upwards by 32-34 mm, releasing part of the clamping distance. This then drives the upper guide ring 27 and the upper slip cage 3 to move upwards. At this moment, the upper slip cage 3 will pull the six upper slips 4 in stages to retract sequentially, releasing space. After this, the rubber sleeve sealing mechanism retracts. The tubing continues to be lifted until the upper locking ring 8 slides down to the locking tooth section of the upper mandrel 2. The upper locking ring 8 engages with the upper mandrel 2, stopping the lower cone 9 from moving downwards. The lower slip cage 12 moves downwards under the weight of the tubing until all six lower slips 10 are forcibly retracted. If the lower slip retraction is obstructed or the upward force is too great, the third shear pin A4 will be sheared, releasing a 24-26mm release distance between the lower slip cage 12 and the upper piston 13. The lower end face of the upper piston 13 is in tight contact with the upper end face of the lower mandrel 15. At this point, the force on the lower end of the packer tubing can be smoothly transmitted to the upper mandrel 2, thus completing the packer release. After release, because the upper locking ring 8 and the upper mandrel 2 are locked, the lower cone 9 and the lower slip cage 12 are relatively fixed, ensuring that the lower slips 10 will not open again during the removal of the tubing, preventing obstruction during packer retraction. At this point, the packer release operation is complete.

[0043] In summary, this high-temperature, high-pressure cutting and retrievable packer features upper and lower anchoring mechanisms located at opposite ends of the rubber sleeve sealing mechanism. It can withstand axial loads of at least 115t in both directions, exhibiting excellent sealing performance. The rubber sleeve sealing mechanism can withstand temperatures up to 232℃ and a gas sealing pressure of 105MPa in the upper and lower annulus. It possesses good anchoring performance and reliable retrieval capabilities. The upper and lower slips employ a multi-set plate-like slip structure, ensuring reliable opening. Compared to integral cylindrical slips, it can accommodate larger casing inner diameters and, compared to cage-type slips, penetrates deeper into the casing, resulting in more reliable anchoring. Retrieval can be performed in stages with forced recovery. In contrast, integral cylindrical slips, after prolonged downhole service, become less elastic and prone to breakage, causing jamming. This packer offers higher retrieval reliability and requires less unsealing force. The lower anchoring mechanism uses a push-sleeve shear pin control, which can adjust the opening timing of the lower slips in real time according to the final setting pressure value. This ensures that sufficient setting force is applied to the rubber sleeve sealing mechanism before the lower slips open the anchoring sleeve, guaranteeing the setting effect. The unsealing method is more efficient, safe, and reliable, with less unsealing force. It adopts a method of cutting the lower mandrel of the packer and then lifting it upwards. Compared with ordinary lift-and-release packers, it can withstand higher pressure and is less prone to unsealing under axial loads. When recovery is required, a special mechanical or electric cutting tool is used to cut the mandrel, after which the packer can be lifted and retrieved.

[0044] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A high-temperature, high-pressure cutting and recyclable packer, comprising an upper connector, an upper mandrel, a lower mandrel, and a lower connector threadedly connected from top to bottom, characterized in that, Also includes: The upper anchoring mechanism is covered in the upper middle part of the upper mandrel and is used to open radially during setting and anchor to the sleeve. A rubber sleeve sealing mechanism, which covers the middle of the upper mandrel, is used to seal the annulus between the oil pipe and the casing during setting; The lower anchoring mechanism is covered in the lower middle part of the upper mandrel and is used to open radially during setting and anchor to the sleeve. The lower locking mechanism is located between the upper mandrel and the lower anchoring mechanism to prevent the lower anchoring mechanism from opening accidentally during unsealing. A setting mechanism, which covers the lower part of the upper mandrel and the outer periphery of the lower mandrel, is used to drive the upper anchoring mechanism, the rubber sleeve sealing mechanism and the lower anchoring mechanism to set. A locking mechanism, which covers the outer periphery of the setting mechanism, is used to prevent the rubber sleeve sealing mechanism from retracting after setting. An unsealing mechanism is provided in the middle of the lower mandrel for cutting the lower mandrel and unlocking the sealing mechanism; The setting mechanism includes an upper piston, an upper piston sleeve, a lower piston, and a lower piston sleeve; the upper piston covers the lower outer periphery of the upper mandrel, and the upper piston sleeve covers the lower outer periphery of the upper piston; the lower end of the upper piston is sealed to the upper piston sleeve and the upper mandrel respectively; the upper outer periphery of the lower mandrel is sealed to the upper piston sleeve; a first piston cavity is formed between the upper piston, the upper piston sleeve, the lower mandrel, and the upper mandrel; a radial first pressure transmission hole is provided on the lower part of the upper mandrel corresponding to the first piston cavity; the upper piston and the upper piston sleeve are threaded together and then connected by a first fixing pin; the upper mandrel and the lower mandrel are threaded together... The components are connected by a threaded joint and a first fixing pin; the lower piston cover is disposed on the outer periphery of the middle part of the lower mandrel, and the lower piston sleeve is disposed on the outer periphery of the lower part of the lower piston; the lower end of the lower piston is sealed to the lower piston sleeve and the lower mandrel; the outer periphery of the upper end of the lower connector is sealed to the lower piston sleeve; a second piston cavity is formed between the lower piston, the lower piston sleeve, the lower connector, and the lower mandrel, and a radial second pressure transmission hole is provided on the lower part of the lower mandrel at a position corresponding to the second piston cavity; the upper end of the lower piston is connected to the lower end of the upper piston sleeve by a first fixing pin; the lower end of the lower piston sleeve is connected to the upper end of the lower connector by a second fixing pin.

2. The high-temperature, high-pressure cutting and recyclable packer according to claim 1, characterized in that: The upper anchoring mechanism includes an upper gauge ring, an upper slip cage, six upper slips, and an upper cone. The upper gauge ring covers the upper part of the upper mandrel, and the fixing screws pass through the upper gauge ring and are inserted into the sliding track groove of the upper mandrel to form an anti-rotation mechanism. The internal reduction in diameter of the upper gauge ring is used to abut against the positioning step of the upper mandrel when the packer is lifted to release part of the release distance, facilitating the smooth release of the packer. The upper slip cage is set on the positioning step of the upper mandrel and is threadedly connected to the upper gauge ring, and is fixedly connected to the upper mandrel shear pin. Six slips are evenly distributed along the circumference of the lower outer periphery of the upper slip cage. The upper cone has six first conical track grooves evenly distributed around its outer circumference. The upper slip has a first T-shaped block adapted to the first T-shaped groove, and a first sliding lug adapted to the first conical track groove at its lower part. The upper slip has multiple slip tooth grooves on its upper end face, and a first inclined plane adapted to the bottom of the first conical track groove on its lower end face. The upper slip is connected to the upper mandrel via shear bolts. The upper cone is connected to the upper mandrel via first shear pins.

3. The high-temperature, high-pressure cutting and recyclable packer according to claim 2, characterized in that: The length of the six first T-shaped grooves gradually increases along the circumference, which facilitates the step-by-step forced recovery of the upper slip; a first limiting step is provided on both sides of the base of the first T-shaped block; a first limiting groove adapted to the first limiting step is provided at the base of the first T-shaped groove; the length of the first limiting step is 40-45mm.

4. The high-temperature, high-pressure cutting and recyclable packer according to claim 1 or 2, characterized in that: The rubber sleeve sealing mechanism consists of, from top to bottom, a support ring, a shoulder, a triangular ring, a protective ring, a side rubber sleeve, a spacer ring, a middle rubber sleeve, a spacer ring, a side rubber sleeve, a protective ring, a triangular ring, a shoulder, and a support ring. The side rubber sleeve and the middle rubber sleeve are made of modified fluororubber. The support ring and the shoulder are made of 20# steel. The protective ring is made of polytetrafluoroethylene. The spacer ring is made of 42CrMo alloy steel.

5. The high-temperature, high-pressure cutting and recyclable packer according to claim 3, characterized in that: The lower anchoring mechanism consists of a lower cone, a lower slip, and a lower slip cage arranged sequentially from top to bottom. Six second conical track grooves are evenly distributed along the circumference of the lower outer periphery of the lower cone. Six second T-shaped grooves are evenly distributed along the circumference of the upper outer periphery of the lower slip cage. A second T-shaped block adapted to the second T-shaped groove is provided at the lower part of the lower slip, and a second sliding lug adapted to the second conical track groove is provided at the lower part of the lower slip. Multiple slip tooth grooves are provided on the upper end face of the lower slip. A second inclined plane adapted to the bottom of the second conical track groove is provided on the lower end face of the lower slip. A push sleeve is provided between the inner periphery of the lower slip and the outer periphery of the upper mandrel. The upper end of the push sleeve is threadedly connected to the lower cone, and the lower end of the push sleeve is connected to the lower slip cage via a second shear pin. The lower slip cage is connected to the upper piston via a third shear pin.

6. The high-temperature, high-pressure cutting and recyclable packer according to claim 5, characterized in that: A second limiting step is provided on both sides of the base of the second T-shaped block; a second limiting groove is provided at the base of the second T-shaped groove to match the second limiting step; the length of the second limiting step is 15-20mm.

7. The high-temperature, high-pressure cutting and recyclable packer according to claim 5, characterized in that: The lower end of the push sleeve has an outwardly extending periphery, on which multiple sets of shear pin shearing holes are evenly distributed; the front end of the periphery is a straight step, which abuts against the inner end face of the lower slip cage; there are multiple second shear pins, and the number of second shear pins is used to adjust the setting pressure value applied to the rubber sleeve sealing mechanism, thereby controlling the timing of the lower slip opening.

8. The high-temperature, high-pressure cutting and recyclable packer according to claim 5, characterized in that: The lower locking mechanism consists of an upper locking ring and an upper anti-rotation screw. The upper locking ring is located between the lower cone and the upper mandrel. The outer and inner circumferences of the upper locking ring are respectively provided with a first locking ring tooth and a second locking ring tooth. The inner circumference of the lower cone is provided with a first serrated thread that meshes with the first locking ring tooth. The lower middle outer circumference of the upper mandrel is provided with a first locking tooth that meshes with the second locking ring tooth during unsealing. The upper locking ring is provided with a groove, and the upper anti-rotation pin passes through the lower cone and is inserted into the groove of the upper locking ring.

9. The high-temperature, high-pressure cutting and recyclable packer according to claim 1 or 2, characterized in that: The locking mechanism includes a lower locking ring, a locking ring sleeve, and a lower anti-rotation pin; the lower locking ring covers the upper part of the lower piston, and the locking ring sleeve covers the outer periphery of the lower locking ring; the lower anti-rotation pin passes through the locking ring sleeve and is inserted into the groove of the lower locking ring; the upper end of the locking ring sleeve is connected to the lower end of the upper piston sleeve by a first shear pin; the lower end of the locking ring sleeve is connected to the upper end of the lower piston sleeve by a first fixing pin; a third locking ring tooth and a fourth locking ring tooth are respectively provided on the outer and inner peripheries of the lower locking ring, and a second serrated thread that meshes with the third locking ring tooth is provided on the inner periphery of the locking ring sleeve; a third locking tooth that matches the fourth locking ring tooth is provided on the outer periphery of the lower piston.

10. The high-temperature, high-pressure cutting and recyclable packer according to claim 1 or 2, characterized in that: The unsealing mechanism includes a pre-cut section and a through-hole ring disposed in the middle of the lower mandrel; the through-hole ring is disposed on the outer periphery of the lower connector and is connected to the lower connector by a second fixing pin.

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