Self-sealing barrel for under-pressure operation equipment

Abstract

The invention discloses a self-sealing barrel for equipment operating under pressure, and relates to the technical field of oil extraction in oil fields, the self-sealing barrel comprises a shell, a gland and a rubber core, the two ends of the shell are open, the gland is used for being buckled and pressed at the top end of the shell, a sealing piece is arranged between the shell and the gland, a center hole is formed in the gland, and the rubber core is arranged in the center hole. The rubber core is fixedly arranged on the gland and is detachably connected with the gland, a fixing structure for fixing the rubber core is arranged on the gland, a through hole is formed in the rubber core, the center hole is communicated with the through hole of the rubber core, and the rubber core is used for being inserted into the shell. The sealing structure has the effects of improving the stability of the sealing performance and being low in maintenance cost.

Description

Technical Field

[0001] The present application relates to the technical field of oil field production, and in particular to a self-sealing cylinder for pressure operation equipment. Background Art

[0002] In the field of oil field production, rod plunger pumping is one of the traditional lifting methods in the world's oil industry and is also the dominant artificial lifting method so far. The first stage of the development of rod pumping technology was the bushing plunger pump, the second stage was the whole barrel plunger pump, and the new stage was the hydraulic self-sealing plunger pump, which has achieved the effects of ultra-low leakage, ultra-low friction, and ultra-high pump efficiency.

[0003] However, the plunger pump working underground has a short service life due to the long-term eccentric wear between the plunger and the pump barrel. The fixed valve is also easily worn by sand or scaled in the ternary drive oil well and loses its function. Therefore, it needs to be replaced regularly. When replacing the pump barrel and the fixed valve, the oil pipe needs to be lifted and lowered. The whole process is time-consuming and labor-intensive, and the maintenance cost of the equipment is high. Summary of the invention

[0004] In view of the problems existing in the prior art, the present application provides a self-sealing cylinder for pressure-operated equipment.

[0005] The present application provides a self-sealing cylinder for pressure working equipment, which adopts the following technical solution: A self-sealing cylinder for pressure-operating equipment comprises a shell, a gland and a rubber core. The shell is provided with openings at both ends. The gland is used to buckle and press on the top of the shell. A sealing member is provided between the shell and the gland. A center hole is provided on the gland. The rubber core is fixed on the gland and detachably connected to the gland. A fixing structure for fixing the rubber core is provided on the gland. A through hole is provided on the rubber core, and the center hole is connected to the through hole of the rubber core. The rubber core is used to be inserted into the shell.

[0006] By adopting the above technical solution, when in use, the shell is fixed at the inlet position of the oil well, and then the gland is hoisted to the top of the shell, and the rubber core is inserted into the shell, and the gland is pressed on the top of the shell by hydraulic equipment, and the gap between the shell and the gland is sealed by a seal. After that, when the oil pipe or other downhole tool passes through the self-sealing tube, it passes through the center hole of the gland, the through hole of the rubber core, and the shell in sequence. At this time, the rubber core will be compressed. After the oil pipe or other downhole tool passes, the rubber core will return to its original state under the action of the elastic preload and tightly adhere to the outer wall of the oil pipe or other downhole tool, thereby playing a sealing role. And by utilizing the elasticity of the rubber core, it can adapt to the changes in the pressure of the space in the well, and seal the oil well space, thereby avoiding the splashing of crude oil in the oil well. The inlet position of the oil well is closed by means of a casing, a gland and a seal arranged between the casing and the gland, and the expansion and contraction force of the rubber core is used to seal the gap between the oil pipe or other downhole tools and the gland, replacing the traditional method of sealing the oil well by setting a pump barrel and a fixed valve. The sealing performance is more stable and the wear of the casing or the gland is avoided. In subsequent maintenance, only the rubber core needs to be replaced, and the maintenance cost is low.

[0007] Optionally, the fixing structure includes a fixing ring and a fixing bolt. The fixing ring is fixedly arranged in the center hole of the pressure cover and is integrally formed with the pressure cover. The bottom end of the fixing ring is provided with a mounting groove along the circumference of the fixing ring. The end of the rubber core is fixedly provided with a metal frame, which is adapted to the mounting groove. The fixing ring is provided with a mounting hole connected to the mounting groove, and the metal frame is provided with a threaded hole adapted to the fixing bolt.

[0008] Optionally, an annular sealing groove is provided on the metal skeleton along the circumference of the metal skeleton, and a sealing ring is provided in the annular sealing groove.

[0009] Optionally, the end of the fixing ring away from the rubber core is provided with a guide slope connected to the interior of the fixing ring.

[0010] Optionally, a guide slide hole connected to the through hole is provided on the top of the rubber core, and the inner diameter of the guide slide hole gradually decreases along the direction approaching the through hole.

[0011] Optionally, the seal includes a sealing steel ring, a first annular groove matching the sealing steel ring is provided at the top end of the shell along the circumference of the shell, and a second annular groove matching the sealing steel ring is provided on the pressure cover along the circumference of the pressure cover.

[0012] Optionally, a pressure measuring port communicating with the interior of the shell is provided on the shell, and a pressure relief port is provided on the side wall of the shell.

[0013] Optionally, the diameter of the outer wall of the rubber core gradually decreases in the direction away from the gland.

[0014] Optionally, a slide groove is opened in the shell along the length direction of the shell, a boost ring is slidably arranged in the slide groove, the boost ring is used to be sleeved on the rubber core, and an elastic part is arranged in the shell for driving the boost ring to slide close to the top of the shell.

[0015] Optionally, the elastic member includes an elastic clamping ring, which is wavy and installed in the slide groove, one end of the elastic clamping ring abuts against the lower side wall of the slide groove, and the other end of the elastic clamping ring abuts against the boosting ring.

[0016] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application seals the inlet position of the oil well through a shell, a gland and a seal arranged between the shell and the gland, and uses the expansion and contraction force of the rubber core to seal the gap between the oil pipe or other downhole tools and the gland, replacing the traditional method of sealing the oil well by setting a pump barrel and a fixed valve. The sealing performance is more stable and the wear of the shell or the gland is avoided. During subsequent maintenance, only the rubber core needs to be replaced, and the maintenance cost is low.

[0017] 2. The present application optimizes the structure of the shell and the pressure cover, and fixes the pressure cover to the top of the shell by quick pressing, which can achieve simple and quick installation and improve installation efficiency; it can also achieve non-destructive pressure testing, eliminate the fixed connection method between the pressure test pipeline or downhole tool and the various structures of the self-sealing tube, and avoid impact damage and surface bite to the pressure test pipeline or downhole tool during connection.

[0018] 3. When the present application is in use, a variety of different types of pressure caps can be integrated, or corresponding rubber cores can be produced according to the type of downhole tools, thereby achieving pressure testing of downhole blowout preventer tools of various types and sizes, thereby improving the scope of application.

[0019] 4. In the present application, the outer wall diameter of the rubber core gradually decreases in the direction away from the pressure cap, so as to facilitate installation into the shell, and a booster ring is arranged in the shell. When the rubber core is installed into the shell, the booster ring is sleeved on the rubber core. As pressure is applied to the pressure cap, the booster ring is squeezed against the side wall of the rubber core under the influence of the inclined surface of the outer wall of the rubber core, so that the rubber core can better fit the side wall of the oil pipe or other downhole tools.

[0020] 5. The boost ring is set in the housing for sliding, and an elastic member is set to drive the boost ring to slide. When pressure is applied to the gland, the boost ring will move a certain distance with the rubber core, and driven by the elastic force of the elastic member, the boost ring always has a certain pressing force on the side wall of the rubber core, thereby avoiding excessive pressing force of the boost ring on the rubber core, causing serious deformation of the rubber core, or even damage. Further, when the pressure in the oil well is too high, resulting in a gap between the rubber core and the oil pipe or other downhole tools, the bottom position of the rubber core will expand and deform outward under the pressure, and exert a certain upward pressure on the boost ring, so that the boost ring moves upward a certain distance. In this process, under the influence of the inclined surface of the outer wall of the rubber core, the boost ring further increases the pressing effect on the rubber core, so that the rubber core is more closely attached to the side wall of the oil pipe or other downhole tools, and the effect of preventing crude oil from seeping out from between the rubber core and the oil pipe or other downhole tools is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application; Figure 2 is a cross-sectional view of the overall structure of an embodiment of the present application; Figure 3 It is a schematic diagram of the structure of the rubber core used in the embodiment of the present application; Figure 4 yes Figure 2 A magnified view of part A; Figure 5 It is a schematic diagram of the structure of the elastic clamping ring used in the embodiment of the present application.

[0022] Explanation of the reference numerals in the accompanying drawings: 1. Shell; 11. Flange; 12. First annular groove; 13. Pressure measuring port; 14. Pressure relief port; 15. Slide groove; 16. Pressurization ring; 17. Elastic clamping ring; 18. Accommodation groove; 19. Stabilizing ring; 2. Pressure cover; 21. Center hole; 22. Lifting hole; 23. Second annular groove; 24. Fixing ring; 241. Mounting groove; 242. Mounting hole; 243. Guide slope; 25. Fixing bolt; 3. Rubber core; 31. Through hole; 32. Metal frame; 321. Threaded hole; 322. Annular sealing groove; 323. Sealing ring; 33. Guide slide hole; 4. Sealing steel ring. DETAILED DESCRIPTION

[0023] The following will be combined with the attached Figure 1 -Attached Figure 5, the technical solutions in the embodiments of the present invention are clearly and completely described. The described embodiments are only possible technical implementations of the present invention, not all possible implementations. Those skilled in the art can completely combine the embodiments of the present invention to obtain other embodiments without creative work, and these embodiments are also within the scope of protection of the present invention.

[0024] The inventor of this application found that the traditional plunger pump used for underground work has a short service life of the pump barrel due to the long-term eccentric wear between the plunger and the pump barrel, and the fixed valve is also easily worn by sand or scaled in the ternary drive oil well and loses its function, so it needs to be replaced regularly. When replacing the pump barrel and the fixed valve, the oil pipe needs to be lifted and lowered. The whole process is time-consuming and labor-intensive, and the maintenance cost of the equipment is high. To this end, this application adopts and discloses a self-sealing cylinder for pressure operation equipment, which mainly adopts the following scheme: The present application embodiment discloses a self-sealing cylinder for pressure working equipment. Figure 1 and Figure 2 , including a shell 1, a gland 2 and a rubber core 3, both ends of the shell 1 are opened, and a flange 11 is provided at the bottom of the shell 1, the flange 11 and the shell 1 are integrally cast, a center hole 21 is provided on the gland 2, the rubber core 3 is fixedly provided on the gland 2, a through hole 31 is provided on the rubber core 3, and the center hole 21 is communicated with the through hole 31 of the rubber core 3, and a lifting hole 22 is provided on the gland 2; the shell 1 is fixed at the inlet position of the oil well through the flange 11 at the bottom, the gland 2 is lifted to the top of the shell 1 through the lifting hole 22 on the gland 2, and the rubber core 3 is inserted into the shell 1, and the gland 2 is pressed against the top of the shell 1 by hydraulic equipment.

[0025] Reference Figure 2 A seal is provided between the shell 1 and the gland 2, and the seal includes a sealing steel ring 4. A first annular groove 12 adapted to the sealing steel ring 4 is provided at the top of the shell 1 along the circumference of the shell 1, and a second annular groove 23 adapted to the sealing steel ring 4 is provided at the bottom of the gland 2 along the circumference of the gland 2. When the gland 2 is pressed tightly against the top of the shell 1, the gap between the shell 1 and the gland 2 is sealed by the sealing steel ring 4, and by placing the sealing steel ring 4 in the first annular groove 12 of the shell 1 and the second annular groove 23 of the gland 2 at the same time, while realizing the positioning of the sealing steel ring 4, the relative position between the gland 2 and the shell 1 can also be positioned, thereby increasing the stability of the gland 2 on the shell 1.

[0026] Reference Figure 2 A pressure measuring port 13 communicating with the interior of the shell 1 is provided on the shell 1, and a pressure relief port 14 is provided on the side wall of the shell 1. When the self-sealing tube is in use, the pressure measuring port 13 is connected to the pressure sensor, and the pressure relief port 14 is connected to the pressure relief pipe. When the pressure in the well is too high, the pressure in the well is relieved by opening the pressure relief port 14 on the side wall of the shell 1.

[0027] Reference Figure 3 The rubber core 3 is made of rubber material, and a metal frame 32 is arranged at the top of the rubber core 3. The metal frame 32 is annular and integrated with the rubber core. The metal frame 32 is adapted to the mounting groove 241. The rubber core 3 is detachably arranged on the gland 2 so that the rubber core 3 can be replaced when it is aged or damaged. Specifically, a fixing structure for fixing the rubber core 3 is arranged on the gland 2.

[0028] Reference Figure 2 and Figure 4 The fixing structure includes a fixing ring 24 and a fixing bolt 25. The fixing ring 24 is coaxially fixed in the center hole 21 of the gland 2 and is integrally formed with the gland 2. A mounting groove 241 is provided at the bottom end of the fixing ring 24 along the circumference of the fixing ring 24. A plurality of mounting holes 242 connected to the mounting groove 241 are opened on the fixing ring 24 along the axial direction of the fixing ring 24. The mounting holes 242 are evenly spaced along the circumference of the mounting groove 241 and are used for the fixing bolts 25 to pass through. A plurality of threaded holes 321 compatible with the fixing bolts 25 are provided on the metal frame 32. The threaded holes 321 correspond one-to-one to the mounting holes 242 on the fixing ring 24.

[0029] Reference Figure 4 In order to improve the sealing between the metal skeleton 32 and the fixing ring 24, an annular sealing groove 322 is opened on the metal skeleton 32 along the circumference of the metal skeleton 32, and a sealing ring 323 is arranged in the annular sealing groove 322. The sealing ring 323 is made of rubber material. When the metal skeleton 32 is installed in the installation groove 241 of the fixing ring 24, the sealing ring 323 presses against the side walls of the metal skeleton 32 and the annular sealing groove 322 respectively, thereby improving the sealing between the metal skeleton 32 and the fixing ring 24.

[0030] Reference Figure 2 and Figure 4 The end of the fixing ring 24 away from the rubber core 3 is provided with a guide bevel 243 connected to the inside of the fixing ring 24. The setting of the guide bevel 243 facilitates the oil pipe or other downhole tools to be inserted into the fixing ring 24 and enter the through hole 31 of the rubber core 3.

[0031] Reference Figure 2 A guide slide hole 33 connected to the through hole 31 is provided at the top of the rubber core 3. The inner diameter of the guide slide hole 33 gradually decreases along the direction approaching the through hole 31. The inner diameter of the through hole 31 is smaller than the sealed oil pipe or other downhole tools. By tilting the side wall of the guide slide hole 33, it is convenient for the oil pipe or other downhole tools to pass through the through hole 31 of the rubber core 3.

[0032] Reference Figure 2 and Figure 5In order to facilitate the insertion of the rubber core 3 into the housing 1 , the diameter of the outer wall of the rubber core 3 gradually decreases in the direction away from the metal frame 32 . In order to make the rubber core 3 better fit the side wall of the oil pipe or other downhole tools, a slide groove 15 is opened in the shell 1 along the length direction of the shell 1, and a boost ring 16 is slidably arranged in the slide groove 15. The inner diameter of the boost ring 16 gradually decreases in the direction away from the top of the shell 1. An elastic member for driving the boost ring 16 to slide toward the top of the shell 1 is arranged in the shell 1. The elastic member includes an elastic clamping ring 17. The elastic clamping ring 17 is wavy and installed in the slide groove 15. One end of the elastic clamping ring 17 abuts against the lower side wall of the slide groove 15, and the other end of the elastic clamping ring 17 abuts against the boost ring 16; when the rubber core 3 is installed to the shell 1, the boost ring 16 is sleeved on the rubber core 3. As pressure is applied to the pressure cover 2, at this time, the boost ring 16 is affected by the inclined surface of the outer wall of the rubber core 3, so that the boost ring 16 squeezes the side wall of the rubber core 3. In order to increase the pressing force of the booster ring 16, a plurality of elastic pressing rings 17 can be superimposed. In addition, the elastic member can also be a spring.

[0033] Furthermore, by slidingly arranging the boost ring 16 in the shell 1, and arranging an elastic clamping ring 17 in the shell 1 for driving the boost ring 16 to slide, when pressure is applied to the pressure cover 2, the boost ring 16 will move a certain distance together with the rubber core 3, and driven by the elastic force of the elastic clamping ring 17, the boost ring 16 will always have a certain clamping force on the side wall of the rubber core 3, thereby avoiding excessive clamping force of the boost ring 16 on the rubber core 3, resulting in serious deformation of the rubber core 3 or even damage.

[0034] Furthermore, when the pressure in the oil well is too high, causing a gap to appear between the rubber core 3 and the oil pipe or other downhole tools, the bottom position of the rubber core 3 will expand and deform outward under the pressure, and exert a certain upward pressure on the booster ring 16, causing the booster ring 16 to move upward a certain distance. In this process, under the influence of the inclined surface of the outer wall of the rubber core 3, the booster ring 16 further increases the compression effect on the rubber core 3, so that the rubber core 3 fits more closely to the side wall of the oil pipe or other downhole tools, and achieves the effect of preventing crude oil from seeping out from between the rubber core 3 and the oil pipe or other downhole tools.

[0035] Reference Figure 2 In order to facilitate the assembly of the boost ring 16 and the elastic clamping ring 17, a receiving groove 18 connected to the slide groove 15 is provided on the top of the shell 1, and a stabilizing ring 19 is fixed in the receiving groove 18 by bolts. By removing the stabilizing ring 19, the slide groove 15 can be fully opened, thereby realizing the assembly of the boost ring 16 and the elastic clamping ring 17.

[0036] The implementation principle of a self-sealing cylinder for pressure-carrying operation equipment in an embodiment of the present application is as follows: when in use, the shell 1 is fixed at the inlet position of the oil well through the flange 11 at the bottom, and the sealing steel ring 4 is placed in the first annular groove 12 at the top of the shell 1, and then the pressure cover 2 is hoisted to the top of the shell 1, and the rubber core 3 is inserted into the shell 1, the sealing steel ring 4 is stuck in the second annular groove 23 of the pressure cover 2, and the pressure cover 2 is pressed against the top of the shell 1 by hydraulic equipment, and the gap between the shell 1 and the pressure cover 2 is sealed by the sealing steel ring 4. Afterwards, when the oil pipe or other downhole tool passes through the self-sealing cylinder, it passes through the center hole 21 of the pressure cover 2, the through hole 31 of the rubber core 3, and the shell 1 in sequence. At this time, the rubber core 3 will be compressed. After the oil pipe or other downhole tool passes through, the rubber core 3 will return to its original state under the action of the elastic preload force, and tightly adhere to the outer wall of the oil pipe or other downhole tool, thereby playing a sealing role. And by utilizing the elasticity of the rubber core 3, it can adapt to the change of the pressure in the well space, and seal the oil well space, thereby avoiding the splashing of crude oil in the oil well. The inlet position of the oil well is sealed by the shell 1, the gland 2 and the sealing steel ring 4 arranged between the shell 1 and the gland 2, and the elastic force of the rubber core 3 is used to seal the gap between the oil pipe or other downhole tools and the gland 2, replacing the traditional way of sealing the oil well by setting a pump barrel and a fixed valve. The sealing performance is more stable and the wear of the shell 1 or the gland 2 is avoided. In the subsequent maintenance, only the rubber core 3 needs to be replaced, and the maintenance cost is low.

[0037] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A self-sealing cylinder for pressure working equipment, characterized in that: The invention comprises a shell (1), a gland (2) and a rubber core (3), wherein both ends of the shell (1) are open, the gland (2) is used for buckling and pressing on the top of the shell (1), a sealing member is provided between the shell (1) and the gland (2), a center hole (21) is provided on the gland (2), the rubber core (3) is fixedly provided on the gland (2) and is detachably connected to the gland (2), a fixing structure for fixing the rubber core (3) is provided on the gland (2), a through hole (31) is provided on the rubber core (3), and the center hole (21) is connected to the through hole (31) of the rubber core (3), and the rubber core (3) is used for being inserted into the shell (1).

2. The self-sealing cylinder for pressure working equipment according to claim 1, characterized in that: The fixing structure comprises a fixing ring (24) and a fixing bolt (25); the fixing ring (24) is fixedly arranged in the center hole (21) of the gland (2) and is integrally formed with the gland (2); a mounting groove (241) is arranged at the bottom end of the fixing ring (24) along the circumference of the fixing ring (24); a metal frame (32) is fixedly arranged at the end of the rubber core (3); the metal frame (32) is matched with the mounting groove (241); a mounting hole (242) connected with the mounting groove (241) is opened on the fixing ring (24); and a threaded hole (321) matched with the fixing bolt (25) is arranged on the metal frame (32).

3. The self-sealing cylinder for pressure working equipment according to claim 2, characterized in that: An annular sealing groove (322) is provided on the metal frame (32) along the circumference of the metal frame (32), and a sealing ring (323) is provided in the annular sealing groove (322).

4. The self-sealing cylinder for pressure working equipment according to claim 2, characterized in that: The end of the fixing ring (24) away from the rubber core (3) is provided with a guide slope (243) which is in communication with the interior of the fixing ring (24).

5. The self-sealing cylinder for pressure working equipment according to claim 1, characterized in that: A guide slide hole (33) communicating with the through hole (31) is provided at the top of the rubber core (3), and the inner diameter of the guide slide hole (33) gradually decreases in a direction approaching the through hole (31).

6. The self-sealing cylinder for pressure working equipment according to claim 1, characterized in that: The sealing component comprises a sealing steel ring (4); a first annular groove (12) adapted to the sealing steel ring (4) is arranged at the top end of the shell (1) along the circumference of the shell (1); and a second annular groove (23) adapted to the sealing steel ring (4) is arranged on the gland (2) along the circumference of the gland (2).

7. The self-sealing cylinder for pressure working equipment according to claim 1, characterized in that: The shell (1) is provided with a pressure measuring port (13) which is in communication with the interior of the shell (1), and the side wall of the shell (1) is provided with a pressure relief port (14).

8. The self-sealing cylinder for pressure working equipment according to claim 1, characterized in that: The diameter of the outer wall of the rubber core (3) gradually decreases in a direction away from the gland (2).

9. The self-sealing cylinder for pressure working equipment according to claim 8, characterized in that: A slide groove (15) is provided in the shell (1) along the length direction of the shell (1), a boost ring (16) is slidably arranged in the slide groove (15), the boost ring (16) is used to be sleeved on the rubber core (3), and an elastic member is provided in the shell (1) for driving the boost ring (16) to slide close to the top of the shell (1).

10. The self-sealing cylinder for pressure working equipment according to claim 9, characterized in that: The elastic member comprises an elastic clamping ring (17), which is wavy and installed in the slide groove (15). One end of the elastic clamping ring (17) abuts against the lower side wall of the slide groove (15), and the other end of the elastic clamping ring (17) abuts against the boosting ring (16).

Images