High-temperature and high-pressure compression type open hole packer

Abstract

The invention discloses a high-temperature and high-pressure compression type open hole packer which adopts two groups of long rubber sleeve structures and has a higher pressure bearing effect and good sealing performance. The piston mechanism adopts a two-stage piston design, and 26.5 tons of piston force can be generated under the pressure of 32 MPa to ensure that the rubber sleeve is fully extruded. When the packer is used, the central pipe is plugged by throwing a ball or lowering a blanking plug, pressurizing liquid is injected into the central pipe to exert pressure, the liquid enters the pressurizing cavity through the liquid through hole to enable the upper piston and the lower piston of the packer to be stressed, when the pressure reaches a set value, the first shear pin and the second shear pin are sheared off, the packer begins to set, and the upper piston and the lower piston continue to move; the upper rubber sleeve and the lower rubber sleeve are compressed, make contact with the well wall and start to form sealing, when the pressure reaches the complete setting pressure, the contact stress of the upper rubber sleeve and the well wall and the contact stress of the lower rubber sleeve and the well wall reach the design value, meanwhile, the one-way locking structure is locked to enable the upper rubber sleeve and the lower rubber sleeve to be kept in the setting state, the ball seat is continuously pressed down, or the blanking plug and the packer are taken out, and setting is completed.

Description

Technical Field

[0001] The present invention relates to the technical field of packers, and particularly to a compression - type open - hole packer used for isolating reservoirs in open - hole staged operations of oil and gas wells to meet the requirements of open - hole staged reconstruction. Background Art

[0002] As one of the key core tools for open - hole staged reconstruction, the performance level and structural characteristics of the open - hole packer directly determine the applicability and effectiveness of the staged reconstruction process. The Shunbei Oilfield is characterized by ultra - deep, ultra - high temperature, and ultra - high pressure. The existing packers in use can no longer fully meet the requirements of temperature and pressure resistance. Therefore, it is necessary to design a compression - type open - hole packer with a temperature resistance of 204°C and a differential pressure resistance of 105 MPa through material selection and structural innovation to meet the requirements of open - hole staged reconstruction in the Shunbei Oilfield.

[0003] However, there is still no device in the prior art that can solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a high - temperature and high - pressure compression - type open - hole packer, which, through material selection and structural innovation, has the performance of a temperature resistance of 204°C and a differential pressure resistance of 105 MPa.

[0005] According to the present invention, a high - temperature and high - pressure compression - type open - hole packer is provided, which includes a central tube, on the outer side of which an upper rubber cylinder and a lower rubber cylinder are arranged at intervals along the axial direction of the central tube. The upper rubber cylinder is located upstream of the lower rubber cylinder. An upper stop structure is formed at the upstream end face of the upper rubber cylinder to abut against the upstream end face, and a lower stop structure is formed at the downstream end face of the lower rubber cylinder to abut against the downstream end face. A bipolar piston structure is sleeved on the outer side of the central tube between the upper rubber cylinder and the lower rubber cylinder. The bipolar piston structure includes an upper piston and a lower piston arranged in inner and outer layers and capable of moving in opposite directions. One end of the upper piston abuts against the upper rubber cylinder, and one end of the lower piston abuts against the lower rubber cylinder. A pressurizing chamber is formed inside the bipolar piston structure, and the pressurizing chamber corresponds to the upper piston and the lower piston. A liquid - passing hole is also provided on the central tube, which penetrates through its side wall and communicates with the pressurizing chamber, so that the pressurizing liquid can enter the pressurizing chamber from the central tube through the liquid - passing hole to push the upper piston and the lower piston to move in opposite directions. A one - way locking structure is arranged between the upper piston and the lower piston so that the upper piston and the lower piston are in a locked state after moving unidirectionally. The bipolar piston structure has an initial state and an action state. In the initial state, it is locked on the central tube by a locking screw, and both the upper rubber cylinder and the lower rubber cylinder are in a natural state. In the action state, the pressurizing liquid enters the pressurizing chamber to push the upper piston and the lower piston, causing the locking screw to be cut off, and then the upper piston and the lower piston move. The moving upper piston compresses the upper rubber cylinder, and the moving lower piston compresses the lower rubber cylinder.

[0006] Preferably, the lower piston includes a first cylinder body and a second cylinder body which are distributed along the axial direction of the central tube and are threadedly connected. Both the first cylinder body and the second cylinder body are sleeved and sealingly slidably connected to the outside of the central tube. The first cylinder body is located upstream of the second cylinder body. An outwardly protruding first outward expansion section is formed on the outer side wall at the upstream end of the first cylinder body. The upstream end of the second cylinder body is provided with a first stepped structure, which includes a first upper stepped surface, a first lower stepped surface and a first vertical inner side surface located between the two. The downstream end surface of the first cylinder body abuts against the first lower stepped surface. The first vertical inner side surface and the outer side wall at the downstream end of the first cylinder body are threadedly connected to connect the first cylinder body and the second cylinder body. The downstream end surface of the second cylinder body abuts against the lower rubber cylinder. The upper piston includes a third cylinder body and a fourth cylinder body which are distributed along the axial direction of the central tube and are threadedly connected. It is sleeved on the outside of the lower piston. The third cylinder body is located upstream of the fourth cylinder body. An inwardly protruding first inward expansion section is formed on the inner side wall at the upstream end of the third cylinder body. The inner side wall of the first inward expansion section is sealingly slidably connected to the outer side wall of the central tube. The first inward expansion section is located upstream of the first outward expansion section and a upstream chamber is formed between the two. The first outward expansion section is sealingly slidably connected to the inner side wall of the third cylinder body. The upstream end surface of the first inward expansion section abuts against the upper rubber cylinder. An inwardly protruding second inward expansion section is formed on the inner side wall at the upstream end of the fourth cylinder body. The inner side wall of the second inward expansion section is sealingly slidably connected to the outer side wall of the first cylinder body. The upstream end of the second cylinder body is sealingly slidably connected to the inner side wall of the fourth cylinder body. A downstream chamber is formed between the second inward expansion section and the first upper stepped surface. The upstream end of the second inward expansion section is provided with a second stepped structure, which includes a second upper stepped surface, a second lower stepped surface and a second vertical inner side surface located between the two. The downstream end surface of the third cylinder body abuts against the second lower stepped surface. The inner side wall of the third cylinder body and the second vertical inner side surface are threadedly connected to connect the third cylinder body and the fourth cylinder body. An upper through hole is opened on the side wall of the central tube corresponding to the upstream chamber, and a lower through hole is opened on the side wall of the central tube corresponding to the downstream chamber. The upstream chamber and the downstream chamber form the pressurizing chamber, and the upper through hole and the lower through hole form the liquid through hole. The position where the second cylinder body extends out of the fourth cylinder body and the central tube are connected by a first shear pin, and the fourth cylinder body and the second cylinder body are connected by a second shear pin. The first shear pin and the second shear pin form the locking screw.

[0007] Preferably, matching ratchet teeth are provided on the outer side wall of the second sleeve and the inner side wall of the fourth sleeve corresponding to it, so that the second sleeve can be locked by the ratchet teeth after moving in the downstream direction, and the fourth sleeve can be locked by the ratchet teeth after moving in the upstream direction.

[0008] Preferably, an upper joint is threadedly connected to the outer sidewall at the upstream end of the central tube, and the downstream end face of the upper joint forms the upper blocking structure. A lower joint is threadedly connected to the outer sidewall at the downstream end of the central tube, and the upstream end face of the lower joint forms the lower blocking structure. The upper joint is connected to the central tube by an internal hexagon flat end set screw, and the lower joint is connected to the central tube by an internal hexagon flat end set screw.

[0009] Preferably, an O-ring back ring and an O-ring are arranged between the upper joint and the central tube to form a sealing structure, and an O-ring back ring and an O-ring are arranged between the lower joint and the central tube to form a sealing structure.

[0010] Preferably, an O-ring back ring and an O-ring are arranged between the first inner expanded section and the central tube to form a sealing structure, an O-ring back ring and an O-ring are arranged between the first outer expanded section and the inner sidewall of the third cylinder to form a sealing structure, an O-ring back ring and an O-ring are arranged between the second inner expanded section and the inner sidewall of the first cylinder to form a sealing structure, and an O-ring back ring and an O-ring are arranged between the upstream end of the second cylinder and the inner sidewall of the fourth cylinder to form a sealing structure.

[0011] Preferably, both the upper rubber cylinder and the lower rubber cylinder are composed of a steel bowl, a copper back ring, a side rubber cylinder, a spacer ring, a rubber cylinder, a spacer ring, a rubber cylinder, a spacer ring, a side rubber cylinder, a copper back ring, and a steel bowl that are sequentially connected in the upstream and downstream directions.

[0012] Preferably, the lengths of the upper rubber cylinder and the lower rubber cylinder are 350 mm.

[0013] Preferably, the O-ring back ring is made of PEEK material.

[0014] It has the following technical effects:

[0015] The sealing mechanism adopts a structure of two groups of long rubber cylinders, namely the upper rubber cylinder and the lower rubber cylinder. The length of a single group of rubber cylinders reaches 350 mm, which has a high pressure-bearing effect and good sealing performance; the piston mechanism adopts a two-stage piston structure, which can generate a piston force of 26.5 tons at a pressure of 32 MPa to ensure that the rubber cylinders are fully squeezed. When in use, after lowering the packer to the predetermined depth, the central pipe is blocked by throwing a ball or lowering a plug, and pressurized liquid is injected into the central pipe to apply pressure. The pressure enters the pressurized chamber through the liquid passage holes, causing the upper and lower pistons of the packer to be stressed. When the pressure reaches the set value, the first shear pin and the second shear pin are cut off, and the packer starts to set. The upper and lower pistons continue to move, and the upper and lower rubber cylinders are compressed, contacting the wellbore and starting to form a seal. When the pressure reaches the full setting pressure, the contact stress between the upper and lower rubber cylinders and the wellbore reaches the design value. At the same time, the one-way locking structure locks to keep the upper and lower rubber cylinders in the set state. Continuing to pressurize to knock down the ball seat or remove the plug, the packer completes setting.

[0016] Preferably, the specific structure of the first cylinder to the fourth cylinder is adopted, so that the upper and lower pistons and the corresponding pressurized chambers are formed simultaneously, simplifying the structure. And the thrust generated by these two pistons simultaneously is 1.5 times the setting force under the same setting pressure compared with a single piston.

[0017] Preferably, the function of the socket head cap screw is to prevent the parts from rotating and moving up and down.

[0018] Preferably, an O-ring backing ring and an O-ring are provided to achieve better sealing. Backing rings are added at both ends of the O-ring to provide support for the rubber ring, prevent the rubber ring from deforming, and improve the sealing ability of the O-ring.

[0019] Preferably, the upper and lower rubber cylinders are respectively combined with four rubber cylinders as sealing elements, and metal spacer rings are added in the four rubber cylinders, and double-metal backing rings are added at both ends. The whole rubber cylinder assembly is in turn: steel bowl + copper backing ring + side rubber cylinder + spacer ring + rubber cylinder + spacer ring + rubber cylinder + spacer ring + side rubber cylinder + copper backing ring + steel bowl; among them, the double-metal backing rings at both ends play a very good supporting role for the rubber cylinders after being squeezed and expanded, ensuring that the rubber cylinders will not flow under high pressure difference; the metal spacer rings between the rubber cylinders ensure that the rubber cylinders are evenly stressed during the extrusion process, ensuring that each rubber cylinder expands fully, and at the same time playing a centering role, making the rubber cylinders contact the wellbore more fully. Description of the Drawings

[0020] The present invention will be described in detail below with reference to the drawings. In the drawings:

[0021] Figure 1 Schematically shows the structure of the high-temperature and high-pressure compressible open-hole packer according to the present invention;

[0022] Figure 2 Is a schematic structural diagram of the upper rubber cylinder or the lower rubber cylinder.

[0023] In the drawings, like reference numerals are used for like parts. The drawings are not drawn to scale.

[0024] Figure 1-2 The reference numerals in the drawings are as follows:

[0025] 1 central tube, 2 upper rubber cylinder, 3 lower rubber cylinder, 4 one-way locking structure, 5 first cylinder body, 6 second cylinder body, 7 first outward expansion section, 8 first step structure, 9 third cylinder body, 10 fourth cylinder body, 11 first inward expansion section, 12 upstream chamber, 13 second inward expansion section, 14 downstream chamber, 15 second step structure, 16 upper through hole, 17 lower through hole, 18 first shear pin, 19 second shear pin, 20 upper joint, 21 lower joint, 22 internal hexagonal flat end set screw, 23 O-ring back ring, 24 O-ring, 25 steel bowl, 26 copper back ring, 27 side rubber cylinder, 28 spacer ring, 29 rubber cylinder. Detailed embodiments

[0026] The present invention will be further described below in conjunction with the drawings.

[0027] The above is only the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art can easily make changes or variations within the disclosure scope of the present invention, and such changes or variations should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

[0028] In combination with Figure 1-2, the present invention provides a high-temperature and high-pressure compression type open-hole packer, which includes a central pipe 1, and an upper rubber cylinder 2 and a lower rubber cylinder 3 are sleeved outside the central pipe and are arranged at intervals along the axial direction of the central pipe. The upper rubber cylinder 2 is located upstream of the lower rubber cylinder 3. An upper stop structure is formed at the upstream end face of the upper rubber cylinder 2 to abut against the upstream end face, and a lower stop structure is formed at the downstream end face of the lower rubber cylinder 3 to abut against the downstream end face. A bipolar piston structure is sleeved outside the central pipe between the upper rubber cylinder 2 and the lower rubber cylinder 3. The bipolar piston structure includes an upper piston and a lower piston which are arranged in an inner and outer layer and can move in opposite directions. One end of the upper piston abuts against the upper rubber cylinder 2, and one end of the lower piston abuts against the lower rubber cylinder 3. A pressurizing chamber is formed in the bipolar piston structure, and the pressurizing chamber corresponds to the upper piston and the lower piston. It also includes a liquid through hole opened on the central pipe 1 and penetrating through its side wall and communicating with the pressurizing chamber, so that the pressurizing liquid can enter the pressurizing chamber from the central pipe 1 through the liquid through hole to push the upper piston and the lower piston to move in opposite directions. A one-way locking structure 4 is arranged between the upper piston and the lower piston so that the upper piston and the lower piston are in a locked state after moving in one direction. The bipolar piston structure has an initial state and an operating state. In the initial state, it is locked on the central pipe 1 by a locking screw and the upper rubber cylinder 2 and the lower rubber cylinder 3 are both in a natural state. In the operating state, the pressurizing liquid enters the pressurizing chamber to push the upper piston and the lower piston, so that the locking screw is cut off and then the upper piston and the lower piston move. The moving upper piston compresses the upper rubber cylinder 2, and the moving lower piston compresses the lower rubber cylinder 3.

[0029] In a specific embodiment, such as Figure 1-2As shown, the lower piston includes a first cylinder body 5 and a second cylinder body 6 which are distributed along the axial direction of the central tube 1 and are threadedly connected. Both the first cylinder body 5 and the second cylinder body 6 are sleeved and sealingly slidably connected to the outside of the central tube 1. The first cylinder body 5 is located upstream of the second cylinder body 6. An outwardly protruding first outward expansion section 7 is formed on the outer side wall at the upstream end of the first cylinder body 5. The upstream end of the second cylinder body 6 is provided with a first stepped structure 8, which includes a first upper stepped surface, a first lower stepped surface, and a first vertical inner side surface located between the two. The downstream end surface of the first cylinder body 5 abuts against the first lower stepped surface. The first vertical inner side surface and the outer side wall at the downstream end of the first cylinder body 5 are threadedly connected to connect the first cylinder body 5 and the second cylinder body 6. The downstream end surface of the second cylinder body 6 abuts against the lower rubber cylinder 3. The upper piston includes a third cylinder body 9 and a fourth cylinder body 10 which are distributed along the axial direction of the central tube 1 and are threadedly connected. It is sleeved on the outside of the lower piston. The third cylinder body 9 is located upstream of the fourth cylinder body 10. An inwardly protruding first inward expansion section 11 is formed on the inner side wall at the upstream end of the third cylinder body 9. The inner side wall of the first inward expansion section 11 is sealingly slidably connected to the outer side wall of the central tube 1. The first inward expansion section 11 is located upstream of the first outward expansion section 7 and a upstream chamber 12 is formed between the two. The first outward expansion section 7 is sealingly slidably connected to the inner side wall of the third cylinder body 9. The upstream end surface of the first inward expansion section 11 abuts against the upper rubber cylinder 2. An inwardly protruding second inward expansion section 13 is formed on the inner side wall at the upstream end of the fourth cylinder body 10. The inner side wall of the second inward expansion section 13 is sealingly slidably connected to the outer side wall of the first cylinder body 5. The upstream end of the second cylinder body 6 is sealingly slidably connected to the inner side wall of the fourth cylinder body 10. A downstream chamber 14 is formed between the second inward expansion section 13 and the first upper stepped surface. The upstream end of the second inward expansion section 13 is provided with a second stepped structure 15, which includes a second upper stepped surface, a second lower stepped surface, and a second vertical inner side surface located between the two. The downstream end surface of the third cylinder body 9 abuts against the second lower stepped surface. The inner side wall of the third cylinder body 9 and the second vertical inner side surface are threadedly connected to connect the third cylinder body 9 and the fourth cylinder body 10. An upper through hole 16 is opened on the side wall of the central tube 1 corresponding to the upstream chamber 12, and a lower through hole 17 is opened on the side wall of the central tube 1 corresponding to the downstream chamber 14. The upstream chamber 12 and the downstream chamber 14 form the pressurizing chamber, and the upper through hole 16 and the lower through hole 17 form the liquid through hole. The position where the second cylinder body 6 extends out of the fourth cylinder body 10 and the central tube 1 are connected by a first shear pin 18, and the fourth cylinder body 10 and the second cylinder body 6 are connected by a second shear pin 19. The first shear pin 18 and the second shear pin 19 form the locking screw.

[0030] The sealing mechanism adopts a structure of two groups of long rubber cylinders, namely the upper rubber cylinder 2 and the lower rubber cylinder 3. The length of a single group of rubber cylinders reaches 350 mm, which has a high pressure-bearing effect and good sealing performance. The piston mechanism adopts a two-stage piston structure, which can generate a piston force of 26.5 tons at a pressure of 32 MPa to ensure that the rubber cylinders are fully squeezed. During use, after the packer is lowered to the predetermined depth, the central tube 1 is blocked by throwing a ball or lowering a plug. Pressurized liquid is injected into the central tube 1 to apply pressure. The pressure enters the pressurized chamber through the liquid passage holes, causing the upper and lower pistons of the packer to be stressed. When the pressure reaches the set value, the first shear pin 18 and the second shear pin 19 are cut off, and the packer starts to set. The upper and lower pistons continue to move, and the upper and lower rubber cylinders are compressed, contacting the wellbore and starting to form a seal. When the pressure reaches the full setting pressure, the contact stress between the upper and lower rubber cylinders and the wellbore reaches the design value. At the same time, the one-way locking structure 4 locks to keep the upper and lower rubber cylinders in the set state. Continue to pump to knock down the ball seat or remove the plug, and the packer completes setting.

[0031] The specific structure of the first cylinder body 5 to the fourth cylinder body 10 is adopted, so that the upper and lower pistons and the corresponding pressurized chambers are formed simultaneously, simplifying the structure. And the thrust generated by these two pistons simultaneously is 1.5 times the setting force under the same setting pressure compared with a single piston.

[0032] In a specific embodiment, matching ratchet teeth are provided on the outer side wall of the second sleeve 6 and the inner side wall of the corresponding fourth sleeve 10, so that the second sleeve 6 can be locked by the ratchet teeth after moving in the downstream direction, and the fourth sleeve 10 can be locked by the ratchet teeth after moving in the upstream direction.

[0033] As Figure 1 shown, an upper joint 20 is externally threaded and connected to the outer side wall at the upstream end of the central tube 1. The downstream end face of the upper joint 20 forms the upper blocking structure. A lower joint 21 is externally threaded and connected to the outer side wall at the downstream end of the central tube 1. The upstream end face of the lower joint 21 forms the lower blocking structure. The upper joint 20 is connected to the central tube 1 through an internal hexagon socket flat point set screw 22, and the lower joint 21 is connected to the central tube 1 through an internal hexagon socket flat point set screw 22.

[0034] In a specific embodiment, an O-ring back ring 23 and an O-ring 24 are arranged between the upper joint 20 and the central tube 1 to form a sealing structure. An O-ring back ring 23 and an O-ring 24 are arranged between the lower joint 21 and the central tube 1 to form a sealing structure.

[0035] An O-ring back ring 23 and an O-ring 24 are arranged between the first inner expansion section 11 and the central tube 1 to form a sealing structure. An O-ring back ring 23 and an O-ring 24 are arranged between the first outer expansion section 7 and the inner side wall of the third cylinder 9 to form a sealing structure. An O-ring back ring 23 and an O-ring 24 are arranged between the second inner expansion section 13 and the inner side wall of the first cylinder 5 to form a sealing structure. An O-ring back ring 23 and an O-ring 24 are arranged between the upstream end of the second cylinder 6 and the inner side wall of the fourth cylinder 10 to form a sealing structure.

[0036] The O-ring back ring 23 and the O-ring 24 are arranged to achieve better sealing. Back rings are added to both ends of the O-ring 24 to provide support for the rubber ring, prevent the rubber ring from deforming, and improve the sealing ability of the O-ring 24.

[0037] In a specific embodiment, both the upper rubber cylinder 2 and the lower rubber cylinder 3 are symmetric structures, specifically composed of a steel bowl 25, a copper back ring 26, a side rubber cylinder 27, a spacer ring 28, a rubber cylinder 29, a spacer ring 28, a rubber cylinder 29, a spacer ring 28, a side rubber cylinder 27, a copper back ring 26, and a steel bowl 25 connected in sequence along the upstream and downstream directions.

[0038] In a specific embodiment, the lengths of the upper rubber cylinder 2 and the lower rubber cylinder 3 are 350 mm.

[0039] In a specific embodiment, the O-ring back ring 23 is made of PEEK material.

Claims

1. A high-temperature and high-pressure compression type open-hole packer, characterized in that, It includes a central tube, with an upper rubber cylinder and a lower rubber cylinder sleeved on the outside of the central tube at intervals along the axial direction of the central tube. The upper rubber cylinder is located upstream of the lower rubber cylinder. An upper stop structure is formed at the upstream end face of the upper rubber cylinder to abut against the upstream end face, and a lower stop structure is formed at the downstream end face of the lower rubber cylinder to abut against the downstream end face. A bipolar piston structure is sleeved on the outside of the central tube between the upper rubber cylinder and the lower rubber cylinder. The bipolar piston structure includes an upper piston and a lower piston arranged in an inner and outer layer and capable of moving in opposite directions. One end of the upper piston abuts against the upper rubber cylinder, and one end of the lower piston abuts against the lower rubber cylinder. A pressurizing chamber is formed inside the bipolar piston structure, and the pressurizing chamber is arranged corresponding to the upper piston and the lower piston. It also includes a liquid through hole opened on the central tube and penetrating its side wall and communicating with the pressurizing chamber, so that the pressurized liquid can enter the pressurizing chamber from the central tube through the liquid through hole to push the upper piston and the lower piston to move in opposite directions. A one-way locking structure is arranged between the upper piston and the lower piston so that the upper piston and the lower piston are in a locked state after moving unidirectionally. The bipolar piston structure has an initial state and an action state. In the initial state, it is locked on the central tube by a locking screw, and the upper rubber cylinder and the lower rubber cylinder are both in a natural state. In the action state, the pressurized liquid enters the pressurizing chamber to push the upper piston and the lower piston, so that the locking screw is cut off, and then the upper piston and the lower piston move. The moving upper piston compresses the upper rubber cylinder, and the moving lower piston compresses the lower rubber cylinder.

2. The high-temperature and high-pressure compression type open-hole packer according to claim 1, wherein The lower piston includes a first cylinder body and a second cylinder body which are distributed along the axial direction of the central tube and are threadedly connected. Both the first cylinder body and the second cylinder body are sleeved and sealingly slidably connected to the outside of the central tube. The first cylinder body is located upstream of the second cylinder body. An outwardly protruding first outward expansion section is formed on the outer side wall at the upstream end of the first cylinder body. The upstream end of the second cylinder body is set as a first stepped structure, which includes a first upper stepped surface, a first lower stepped surface and a first vertical inner side surface located between the two. The downstream end surface of the first cylinder body abuts against the first lower stepped surface. The first vertical inner side surface and the outer side wall at the downstream end of the first cylinder body are threadedly connected to connect the first cylinder body and the second cylinder body. The downstream end surface of the second cylinder body abuts against the lower rubber cylinder. The upper piston includes a third cylinder body and a fourth cylinder body which are distributed along the axial direction of the central tube and are threadedly connected. It is sleeved on the outside of the lower piston. The third cylinder body is located upstream of the fourth cylinder body. An inwardly protruding first inward expansion section is formed on the inner side wall at the upstream end of the third cylinder body. The inner side wall of the first inward expansion section is sealingly slidably connected to the outer side wall of the central tube. The first inward expansion section is located upstream of the first outward expansion section and a upstream chamber is formed between the two. The first outward expansion section is sealingly slidably connected to the inner side wall of the third cylinder body. The upstream end surface of the first inward expansion section abuts against the upper rubber cylinder. An inwardly protruding second inward expansion section is formed on the inner side wall at the upstream end of the fourth cylinder body. The inner side wall of the second inward expansion section is sealingly slidably connected to the outer side wall of the first cylinder body. The upstream end of the second cylinder body is sealingly slidably connected to the inner side wall of the fourth cylinder body. A downstream chamber is formed between the second inward expansion section and the first upper stepped surface. The upstream end of the second inward expansion section is set as a second stepped structure, which includes a second upper stepped surface, a second lower stepped surface and a second vertical inner side surface located between the two. The downstream end surface of the third cylinder body abuts against the second lower stepped surface. The inner side wall of the third cylinder body and the second vertical inner side surface are threadedly connected to connect the third cylinder body and the fourth cylinder body. An upper through hole is opened on the side wall of the central tube corresponding to the upstream chamber, and a lower through hole is opened on the side wall of the central tube corresponding to the downstream chamber. The upstream chamber and the downstream chamber form the pressurizing chamber, and the upper through hole and the lower through hole form the liquid through hole. The position where the second cylinder body extends out of the fourth cylinder body and the central tube are connected by a first shear pin, and the fourth cylinder body and the second cylinder body are connected by a second shear pin. The first shear pin and the second shear pin form the locking screw.

3. The high-temperature and high-pressure compression type open-hole packer according to claim 2, characterized in that, Matching ratchet teeth are provided on the outer side wall of the second sleeve and the inner side wall of the fourth sleeve corresponding thereto, so that the second sleeve can be locked by the ratchet teeth after moving in the downstream direction, and the fourth sleeve can be locked by the ratchet teeth after moving in the upstream direction.

4. The high-temperature and high-pressure compression type open-hole packer according to claim 3, wherein An upper joint is externally threaded and connected to the outer sidewall at the upstream end of the central tube. The downstream end face of the upper joint forms the upper retaining structure. A lower joint is externally threaded and connected to the outer sidewall at the downstream end of the central tube. The upstream end face of the lower joint forms the lower retaining structure. The upper joint is connected to the central tube by an internal hexagon flat end set screw. The lower joint is connected to the central tube by an internal hexagon flat end set screw.

5. The high-temperature and high-pressure compression type open-hole packer according to claim 4, wherein, An O-ring back ring and an O-ring are arranged between the upper joint and the central tube to form a sealing structure. An O-ring back ring and an O-ring are arranged between the lower joint and the central tube to form a sealing structure.

6. The high-temperature and high-pressure compression type open-hole packer according to claim 3, wherein, An O-ring back ring and an O-ring are arranged between the first inner expansion section and the central tube to form a sealing structure. An O-ring back ring and an O-ring are arranged between the first outer expansion section and the inner sidewall of the third cylinder to form a sealing structure. An O-ring back ring and an O-ring are arranged between the second inner expansion section and the inner sidewall of the first cylinder to form a sealing structure. An O-ring back ring and an O-ring are arranged between the upstream end of the second cylinder and the inner sidewall of the fourth cylinder to form a sealing structure.

7. The high-temperature and high-pressure compression type open-hole packer according to claim 6, wherein Both the upper rubber cylinder and the lower rubber cylinder are composed of a steel bowl, a copper back ring, a side rubber cylinder, a spacer ring, a rubber cylinder, a spacer ring, a rubber cylinder, a spacer ring, a side rubber cylinder, a copper back ring, and a steel bowl that are sequentially connected in the upstream and downstream directions.

8. The high-temperature and high-pressure compression type open-hole packer according to claim 7, wherein, The lengths of the upper rubber cylinder and the lower rubber cylinder are 350 mm.

9. The high-temperature and high-pressure compression type open-hole packer according to claim 7, characterized in that, The O-ring back ring is made of PEEK material.

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