Intelligent vulcanizing tank for underground forming packer of oil and gas well

Abstract

The intelligent vulcanizing tank comprises a sliding sealing ring, one end of the sliding sealing ring is connected with a first end cover, the other end of the sliding sealing ring is connected with a second end cover, the first end cover and the second end cover are each provided with a fixing baffle, and fixing pins are arranged on the fixing baffles in the radial direction of the fixing baffles. A pushing mechanism is arranged in the sliding sealing ring and connected with one end of an air suction mechanism, and the other end of the air suction mechanism penetrates out of the sliding sealing ring. The problems that an existing vulcanizing tank can generate steam corrosion on a pipe body or a pipe end thread, and a pre-forming space is irregular are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of packer rubber vulcanization, and particularly relates to an intelligent vulcanizing tank for downhole forming packers in oil and gas wells. Background Art

[0002] The characteristics of a forming packer compared with an ordinary packer are as follows: 1. It does not need to be set in place by mechanical or hydraulic means after being lowered to the target position in the well; 2. The rubber generally completes corresponding downhole functions through its own changes, such as expansion, melting, etc.; 3. The diameter of the rubber generally matches the inner diameter of the wellbore with little change, while the length requirement is determined according to on-site needs, and the length requirement has a large elasticity (0.1 m to 20 m), and generally the length is relatively long (for example, for sealing water layers, fracturing stage sealing, etc., the rubber length of more than 3 m is required).

[0003] The vulcanization process of packer rubber is a key process that determines the downhole service performance. Especially for forming packers, the requirements for rubber are very high. Generally, the raw materials of raw rubber are relatively expensive. Once the vulcanization process is improper, it will cause cracking, delamination, and chipping of the downhole rubber, and finally all fail. The currently widely used vulcanization method for forming packers is made by referring to the production method of a roller rubber cylinder. The specific method is to first helically wind the raw rubber around the outer wall of the pipe body, then wrap the raw rubber with a sealing strip for 10 - 20 layers, and then fix it around the sealing strip with steel wire or steel strip, etc. Then the whole packer is placed in a vulcanizing tank and vulcanized according to certain temperature and pressure requirements. These processes will cause the following problems: 1. The pipe body and end rings are made of metal materials, and there will be strong steam corrosion in the vulcanizing tank, affecting the strength of being lowered into the well. Especially when the two ends of the pipe body are gas-tight threads, this corrosion will inevitably lead to the thread sealing performance; 2. The preforming method of the sealing strip + steel wire is itself a soft shell method, which will cause the preforming space of rubber vulcanization to be irregular, resulting in uneven internal stress of the rubber, which is also the main reason for delamination and cracking during the later use of the rubber. Based on this, an intelligent vulcanizing tank for downhole forming packers in oil and gas wells is very necessary. Summary of the Invention

[0004] The purpose of the invention is to provide an intelligent vulcanizing tank for downhole forming packers in oil and gas wells, which solves the problems of steam corrosion of the pipe body or pipe end threads and irregular preforming space of the existing vulcanizing tank.

[0005] The technical solution adopted by the invention is that an intelligent vulcanizing tank for downhole forming packers in oil and gas wells includes a sliding seal ring. One end of the sliding seal ring is connected with a first end cover, and the other end of the sliding seal ring is connected with a second end cover. Fixed baffles are arranged on both the first end cover and the second end cover. Fixed pins are arranged along the radial direction of the fixed baffles. A pushing mechanism is arranged inside the sliding seal ring. The pushing mechanism is connected with one end of an air suction mechanism, and the other end of the air suction mechanism passes through the sliding seal ring.

[0006] The features of the present invention also lie in that

[0007] The sliding seal ring includes a middle sliding seal ring. One end of the middle sliding seal ring is connected with a side sliding seal ring I through an O-ring I, and the other end of the middle sliding seal ring is connected with a side sliding seal ring II through an O-ring II. The side sliding seal ring I is connected with the end cover I through a gas-tight thread, and the side sliding seal ring II is connected with the end cover II through a gas-tight thread. Both the side sliding seal ring I and the side sliding seal ring II are provided with inlets and outlets.

[0008] The middle sliding seal ring includes a thick-wall section I, and thin-wall sections I are arranged at both ends of the thick-wall section. Both the side sliding seal ring I and the side sliding seal ring II include a thick-wall section II, and a thin-wall section II is arranged at one end of the thick-wall section II close to the middle sliding seal ring. The thin-wall section I and the thin-wall section II are arranged correspondingly.

[0009] The pushing mechanism includes a number of preformed arc-shaped push plates. The number of preformed arc-shaped push plates forms a cylindrical shape. One end of each preformed arc-shaped push plate is connected with one end of a hydraulic push rod, and the other end of the hydraulic push rod passes through the sliding seal ring and is connected with a hydraulic cylinder. An air suction channel is arranged on the preformed arc-shaped push plate, and the air suction channel is connected with an air suction mechanism.

[0010] A push rod sliding seal device is arranged at the connection part of the hydraulic push rod and the sliding seal ring.

[0011] The air suction mechanism includes an air suction hose. One end of the air suction hose is connected with the air suction channel, and the other end of the air suction hose passes through the sliding seal ring and is connected with an exhaust pump.

[0012] An air suction channel sliding seal ring is arranged at the connection part of the air suction hose and the sliding seal ring.

[0013] On one side of the end cover I and the end cover II close to the pushing mechanism, end fixing grooves are arranged, and end sealing O-rings are arranged in the end fixing grooves. Temperature and pressure sensing detection meters are arranged on both the end cover I and the end cover II. Sliding rubber rings are arranged at the openings at one ends of the end cover I and the end cover II far away from the sliding seal ring.

[0014] A flange baffle is arranged on one side of the end sealing O-ring far away from the end fixing groove, and a baffle inner rubber ring is arranged at the inner circular end face of the flange baffle.

[0015] The beneficial effects of the present invention are:

[0016] (1) For the intelligent vulcanizing tank of the downhole forming packer in oil and gas wells of the present invention, only the rubber part of the packer is vulcanized, and no steam corrosion or the like will be caused to the pipe body or the pipe end thread.

[0017] (2) The axial length of the intelligent vulcanizing tank for downhole forming packers of the present invention can be changed by sliding the side sliding seal ring 1 and the side sliding seal ring 2, which better conforms to the characteristic that the change amplitude of the length of the forming packer is relatively large;

[0018] (3) For the intelligent vulcanizing tank for downhole forming packers of the present invention, the shape of the preformed arc-shaped push plate is regular, which can ensure that the preforming process of the raw rubber is carried out in a uniform geometric environment, thereby avoiding excessive internal stress of the rubber. At the same time, it directly solves the problem of milling the formed raw rubber with a tool circle on a lathe and protects the protective film formed in the warm pressing environment;

[0019] (4) For the intelligent vulcanizing tank for downhole forming packers of the present invention, the usage method of the preformed arc-shaped push plate is flexible and variable. It is possible to choose to push the push plate tightly with a push rod, or to wrap the rubber in a way that the push rod is axially free and radially constrained. Similarly, it is possible to choose not to use the push plate and wrap the rubber in the way of using a sealing strip + steel wire. Brief Description of the Drawings

[0020] Figure 1 is the topological structure diagram of the intelligent vulcanizing tank for downhole forming packers of the present invention;

[0021] Figure 2 is the schematic diagram of the connection relationship between the end ring and the preformed arc-shaped push plate of the intelligent vulcanizing tank for downhole forming packers of the present invention;

[0022] Figure 3 is the schematic diagram of the structure of the preformed arc-shaped push plate of the intelligent vulcanizing tank for downhole forming packers of the present invention;

[0023] Figure 4 is the schematic diagram of the connection relationship between the sliding rubber ring and the end sealing O-ring of the intelligent vulcanizing tank for downhole forming packers of the present invention.

[0024] In the figure, 1. Casing, 2. Fixed baffle, 3. Fixed pin, 4. End cover 1, 5. Gas sealing thread, 6. Inlet and outlet, 7. Side sliding seal ring 1, 8. O-ring 1, 9. Hydraulic cylinder, 10. Middle sliding seal ring, 11. O-ring 2, 12. Side sliding seal ring 2, 13. End cover 2, 14. Temperature and pressure sensing detection table, 15. Hydraulic push rod, 16. Rubber, 17. End ring, 18. End ring fixing pin, 19. Sliding rubber ring, 20. End sealing O-ring, 21. End fixing groove, 22. Flange baffle, 23. Inner rubber ring of the baffle, 24. Push rod sliding seal device, 25. Preformed arc-shaped push plate, 26. End sealing O-ring of the push plate, 27. Suction channel, 28. Suction channel sliding seal ring, 29. Suction hose, 30. Exhaust pump. Detailed Embodiments

[0025] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0026] Embodiment 1

[0027] The intelligent vulcanizing tank for downhole forming packers in oil and gas wells of the present invention has a structure as Figure 1 shown, including a sliding seal ring. One end of the sliding seal ring is connected to a first end cap 4, and the other end of the sliding seal ring is connected to a second end cap 13. Fixed baffles 2 are provided on both the first end cap 4 and the second end cap 13. Fixed pins 3 are arranged radially along the fixed baffles 2, and the fixed baffles 2 are fixed on the casing 1 by the fixed pins 3. A pushing mechanism is arranged inside the sliding seal ring, and the pushing mechanism is connected to one end of an air suction mechanism, and the other end of the air suction mechanism passes through the sliding seal ring. The fixed baffle 2 has two functions: (1) applying a certain axial compression force to the end sealing O-ring 20 to make there be a certain pre-tightening force between the end sealing O-ring 20 - flange baffle 22 - end ring 17; (2) preventing the side sliding seal ring one 7 and the side sliding seal ring two 12 from sliding towards both ends respectively under pressure during the vulcanization pressure buildup process.

[0028] The vulcanizing tank of the present invention is suitable for vulcanizing the rubber 16 on the packer. The packer includes a casing 1, on which the rubber 16 is provided. End rings 17 are provided at both ends of the rubber 16 on the casing 1, and end ring fixing pins 18 are provided on the end rings 17.

[0029] The sliding seal ring includes a middle sliding seal ring 10. One end of the middle sliding seal ring 10 is connected to a side sliding seal ring one 7 through an O-ring one 8, and the other end of the middle sliding seal ring 10 is connected to a side sliding seal ring two 12 through an O-ring two 11. The side sliding seal ring one 7 is connected to the first end cap 4 through an airtight thread 5, and the side sliding seal ring two 12 is connected to the second end cap 13 through an airtight thread 5. Inlets and outlets 6 are provided on both the side sliding seal ring one 7 and the side sliding seal ring two 12, and the inlets and outlets 6 are used for the medium fluid to enter, exit or circulate during the vulcanization process.

[0030] The middle sliding seal ring 10 includes a thick-wall section I, and thin-wall sections I are provided at both ends of the thick-wall section. Both the side sliding seal ring I 7 and the side sliding seal ring II 12 include a thick-wall section II, and a thin-wall section II is provided at one end of the thick-wall section II close to the middle sliding seal ring 10. The thin-wall section I and the thin-wall section II are correspondingly arranged, that is, the thin-wall section II of the side sliding seal ring I 7 and the thin-wall section I form a certain annular space, and an O-ring I 8 is provided between the thin-wall section II of the side sliding seal ring I 7 and the thin-wall section I. The thin-wall section II of the side sliding seal ring II 12 and the thin-wall section I form a certain annular space, and an O-ring II 11 is provided between the thin-wall section II of the side sliding seal ring II 12 and the thin-wall section I. Thus, by adjusting the contact positions between the thin-wall section II of the side sliding seal ring I 7 and the thin-wall section I, and between the thin-wall section II of the side sliding seal ring II 12 and the thin-wall section I, the length of the vulcanizing tank of the present invention is changed to adapt to packers with different lengths of raw rubber; chamfers are provided at both ends of the middle sliding seal ring 10, and chamfers are also provided at one end of the side sliding seal ring I 7 and the side sliding seal ring II 12 close to the middle sliding seal ring 10, aiming to facilitate embedding the O-ring I 8 into the annular space inside the middle sliding seal ring 10 and the side sliding seal ring I 7, and embedding the O-ring II 11 into the annular space inside the middle sliding seal ring 10 and the side sliding seal ring II 12.

[0031] As Figure 2 and Figure 3 shown, the pushing mechanism includes a number of preformed arc-shaped push plates 25. The number of preformed arc-shaped push plates 25 forms a cylindrical shape. One end of each preformed arc-shaped push plate 25 is connected to one end of a hydraulic push rod 15. The other end of the hydraulic push rod 15 passes through the sliding seal ring and is connected to a hydraulic cylinder 9. A push plate end seal O-ring 26 is provided between the preformed arc-shaped push plate 25 and the end ring 17. The push plate end seal O-ring 26 mainly contacts the end ring 17 of the formed packer, so as to play a role in separating the rubber from the annular space of the vulcanizing tank. A push rod sliding seal device 24 is provided at the connection between the hydraulic push rod 15 and the sliding seal ring. The push rod sliding seal device 24 is used to ensure the sliding seal of the hydraulic push rod 15. An air suction channel 27 is provided on the preformed arc-shaped push plate 25. The air suction channel 27 is connected to an air suction mechanism. When the push plate end seal O-ring 26 squeezes the rubber, it can cooperate with the air suction channel 27, the air suction channel sliding seal ring 28, the air suction hose 29, and the exhaust pump 30 to suck and discharge the gas in the raw rubber, so as to solve the problem that the air and water vapor are heavy in southern factories and the rubber products contain a large amount of gas.

[0032] The air suction mechanism includes an air suction hose 29. One end of the air suction hose 29 is connected to the air suction channel 27. The other end of the air suction hose 29 passes through the sliding seal ring and is connected to the exhaust pump 30. An air suction channel sliding seal ring 28 is provided at the connection between the air suction hose 29 and the sliding seal ring.

[0033] Embodiment 2

[0034] Based on Embodiment 1, as Figure 4 shown, on the side of the first end cap 4 and the second end cap 13 close to the pushing mechanism, end fixing grooves 21 are provided. End sealing O-rings 20 are arranged in the end fixing grooves 21. The end sealing O-rings 20 are used to seal the medium during the vulcanization process. Temperature and pressure sensing detection gauges 14 are arranged on both the first end cap 4 and the second end cap 13. Sliding rubber rings 19 are arranged between the first end cap 4 and the casing 1 and between the second end cap 13 and the casing 1. The sliding rubber rings 19 are used to avoid abrasion and scratching of the surface of the casing 1 as much as possible during the process of sleeving the first end cap 4 and the second end cap 13.

[0035] Embodiment 3

[0036] Based on Embodiment 2, a flange baffle 22 is arranged between the end sealing O-ring 20 and the end ring 17. A baffle inner rubber ring 23 is arranged between the flange baffle 22 and the casing 1. The surface of the flange baffle 22 and the surface of the end of the packer meet the smoothness requirements for gas sealing. The baffle inner rubber ring 23 is used to avoid abrasion and scratching of the casing surface.

[0037] The working principle of the intelligent vulcanizing tank for the downhole forming packer of oil and gas wells of the present invention is as follows: Place the packer wound with rubber 16 in the middle sliding sealing ring 10 of the vulcanizing tank of the present invention. Then, put the first side sliding sealing ring 7 and the second side sliding sealing ring 12 on both ends of the packer respectively. Connect the first end cap 4 to the end of the upper first side sliding sealing ring 7, and connect the second end cap 13 to the end of the second side sliding sealing ring 12. Tighten the fixing pin 3 for fixation. Then, fluid medium can be applied at the inlet and outlet according to the requirements of temperature, medium, pressure, etc. of the raw rubber manufacturer. The temperature and pressure sensing detection gauge is used to monitor the temperature and pressure values in the annulus. The application of the fluid medium can be selected as circulation or pressure holding. The use method of the preformed arc-shaped push plate 25 is flexible. It can be selected to drive the hydraulic cylinder 9 to push the hydraulic push rod 15 to tighten the push plate under certain temperature conditions, so as to strictly standardize the vulcanization space of the raw rubber and ensure the temperature conditions. It can also be selected that the push rod is axially free and radially constrained to wrap the rubber. Under a certain temperature and pressure medium environment, the vulcanization space of the raw rubber is semi-strictly standardized in this way to ensure the temperature and pressure conditions. Similarly, it can be selected not to use the push plate and use the method of sealing strip + steel wire to wrap the rubber. Under a certain temperature and pressure medium environment, the temperature and pressure conditions are ensured in this way.

Claims

1. Intelligent vulcanizing tank for forming packer in oil and gas wells, characterized by: The invention comprises a sliding sealing ring, one end of which is connected to an end cover 1 (4), and the other end of which is connected to an end cover 2 (13). Both the end cover 1 (4) and the end cover 2 (13) are provided with a fixed baffle (2), and a fixed pin (3) is provided on the fixed baffle (2) along its radial direction. A pushing mechanism is provided inside the sliding sealing ring, and the pushing mechanism is connected to one end of an air suction mechanism, and the other end of the air suction mechanism passes through the sliding sealing ring.

2. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 1, characterized in that: The sliding sealing ring comprises a middle sliding sealing ring (10), one end of the middle sliding sealing ring (10) is connected to a side sliding sealing ring (7) via an O-ring (8), the other end of the middle sliding sealing ring (10) is connected to a side sliding sealing ring (12) via an O-ring (11), the side sliding sealing ring (7) is connected to an end cover (4) via an air-sealing thread (5), the side sliding sealing ring (12) is connected to an end cover (13) via an air-sealing thread (5), and both the side sliding sealing ring (7) and the side sliding sealing ring (12) are provided with an inlet and outlet (6).

3. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 2 is characterized in that: The middle sliding sealing ring (10) includes a thick-walled section I, and thin-walled sections I are arranged at both ends of the thick-walled section. The side sliding sealing ring 1 (7) and the side sliding sealing ring 2 (12) both include a thick-walled section II, and thin-walled section II is arranged at one end of the thick-walled section II close to the middle sliding sealing ring (10), and the thin-walled section I and the thin-walled section II are arranged correspondingly.

4. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 1, characterized in that: The pushing mechanism comprises a plurality of preformed arc push plates (25), and the plurality of preformed arc push plates (25) are cylindrical. Each of the preformed arc push plates (25) is connected to one end of a hydraulic push rod (15), and the other end of the hydraulic push rod (15) passes through a sliding sealing ring and is connected to a hydraulic cylinder (9). An air suction channel (27) is provided on the preformed arc push plate (25), and the air suction channel (27) is connected to the air suction mechanism.

5. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 4 is characterized in that: A push rod sliding sealing device (24) is provided at the connection between the hydraulic push rod (15) and the sliding sealing ring.

6. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 4, characterized in that: The air suction mechanism comprises an air suction hose (29), one end of which is connected to the air suction channel (27), and the other end of which passes through a sliding sealing ring and is connected to an exhaust pump (30).

7. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 6, characterized in that: An air intake channel sliding sealing ring (28) is provided at the connection between the air intake hose (29) and the sliding sealing ring.

8. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 1, characterized in that: The end cover 1 (4) and the end cover 2 (13) are both provided with an end fixing groove (21) on a side close to the pushing mechanism, and an end sealing O-ring (20) is provided in the end fixing groove (21). The end cover 1 (4) and the end cover 2 (13) are both provided with a temperature and pressure sensing detection gauge (14), and a sliding rubber ring (19) is provided at an opening of one end of the end cover 1 (4) and the end cover 2 (13) away from the sliding sealing ring.

9. The intelligent vulcanizing tank for forming packers in oil and gas wells according to claim 8, characterized in that: A flange baffle (22) is provided on the side of the end sealing O-ring (20) away from the end fixing groove (21), and an inner baffle rubber ring (23) is provided on the inner circular end surface of the flange baffle (22).

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