Totally sealed leak-proof oil production wellhead

Abstract

The application relates to the technical field of oil extraction wellheads, and discloses a full-sealing and leakage-proof oil extraction wellhead, which comprises a pipe valve, an oil pipe piece is arranged below the pipe valve, a sleeve pipe piece is connected to the bottom of the oil pipe piece, and a sealing assembly is arranged on the oil pipe piece; the sealing assembly comprises a flow channel sealing device, an air charging sealing device and a filtering device. The full-sealing and leakage-proof oil extraction wellhead can provide liquid to surround and seal the connecting position of the Christmas tree through the arranged flow channel sealing device, the principle is similar to the bowl sealing of the cover of the "sour cabbage jar", the absolute sealing of the inner and outer layers is guaranteed, the liquid is arranged around the connecting position of each component of the pipe valve, then the liquid is solidified after the room temperature, a solidified sealing layer is generated, the overall sealing of oil and gas is realized, the sealing mode can provide good sealing effect for the oil circuit, and the sealing effect will not be reduced with the limitation of the use time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil production wellheads, in particular to a full-sealing and leakage-proof oil production wellhead. BACKGROUND

[0002] It is well known that the problem of oil leakage at wellheads is a long-term concern. Oil leakage at wellheads not only affects the appearance, but also causes environmental pollution and waste of energy, and increases the workload of oil production workers. The main reasons for oil leakage at wellheads include operation problems, measure problems, management problems, quality problems, and formation problems. Once oil leakage occurs at the oil production wellhead, the oil pipeline needs to be immediately shut down to reduce the waste caused by oil leakage.

[0003] The current oil production wellhead uses multiple control valves to connect and control the pumping of the oil circuit. The connection of multiple valves directly forms an oil tree wellhead device. The sealing of the connection is particularly important. If leakage occurs, the safety of oil production cannot be effectively guaranteed. The traditional sealing method is to use a sealing gasket to connect and seal, and to use multiple seals to ensure the sealing effect. However, the use of a rubber gasket is accompanied by the continuous use of the wellhead or the longer service life. The fatigue strength of the sealing gasket and the corrosion of the oil circuit cannot be avoided, which may cause damage and lead to leakage of the oil production pipeline. Therefore, a full-sealing and leakage-proof oil production wellhead is proposed to solve the above problems. SUMMARY

[0004] (I) Technical problems solved

[0005] In view of the deficiencies in the prior art, the present application provides a full-sealing and leakage-proof oil production wellhead, which solves the problem of poor sealing effect of the oil production wellhead in the prior art.

[0006] (II) Technical solutions

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions: a full-sealing and leakage-proof oil production wellhead, comprising a pipe valve, an oil pipe piece is arranged below the pipe valve, a sleeve piece is connected to the bottom of the oil pipe piece, a slip-type hanger is arranged in the sleeve piece, and a sealing assembly is arranged on the oil pipe piece; the sealing assembly comprises a flow channel sealing device, an inflation sealing device, and a filtering device; the flow channel sealing device is used to provide a liquid flow channel to achieve liquid solidification sealing of the pipe valve, the oil pipe piece, and the sleeve piece; the inflation sealing device uses the flow pressure of the pipe valve to provide extrusion inflation type fastening sealing; and the filtering device is used to filter the oil during oil production.

[0008] Preferably, the flow channel sealing device comprises a hollow sleeve fixed on the surface of the pipe valve, the pipe valve is internally provided with a flow channel groove, the oil pipe is provided with a deposition groove, the deposition groove is communicated with the hollow sleeve through the flow channel groove, and the oil pipe is provided with a sealing gasket abutting against the pipe valve and arranged outside the deposition groove.

[0009] Preferably, the surface of the oil pipe is provided with a flow channel groove, the inside of the oil pipe is provided with a communication groove, the flow channel groove is communicated with the deposition groove through the communication groove, and the surface of the sleeve pipe is provided with a plurality of rubber pads connected with the oil pipe.

[0010] Preferably, the top of the sleeve pipe is provided with an opening groove communicated with the flow channel groove, the inside of the pipe valve is provided with a bearing seat, and the bearing seat is provided with a volume groove above.

[0011] Preferably, the outer surface of the pipe valve is provided with a liquid storage pipe communicated with a filling pipe, the filling pipe is threadedly connected with a sealing cover, the liquid storage pipe is communicated with the hollow sleeve through a branch pipe, and the inside of the hollow sleeve is provided with a colored sealing liquid.

[0012] Preferably, the air inflation sealing device comprises an impeller, the top of the impeller is connected with a partition plate through a compression spring, the partition plate is fixed in the inside of the pipe valve, the center of the impeller is fixedly connected with a moving shaft, the moving shaft is installed with a filter plate, the filter plate is connected with a piston sleeve through a plurality of supporting rods, the inside of the pipe valve is provided with a piston cavity, the piston sleeve is slidably connected in the inside of the piston cavity, the inside of the pipe valve is provided with a gas groove, one end of the gas groove is connected with a hollow rubber pad, and the other end of the gas groove is communicated with the piston cavity.

[0013] Preferably, the hollow rubber pad comprises a rubber pipe, the rubber pipe is provided with an inflation terminal, the inflation terminal is communicated with the bottom of the gas groove, and the rubber pipe is clamped at the connection between the pipe valve and the oil pipe.

[0014] Preferably, the filter device comprises a telescopic spring, the top of the telescopic spring is connected with a scraping plate, the bottom of the telescopic spring is connected with the bearing seat, the surface of the scraping plate abuts against the bottom of the filter plate, and the filter plate is provided with a filter hole.

[0015] Preferably, the bottom of the filter plate is in a conical structure, the surface of the moving shaft is provided with a long groove, and the scraping plate is slidably connected on the long groove.

[0016] (Three) beneficial effects

[0017] Compared with the prior art, the present application provides a full-sealing anti-leakage oil production wellhead, which has the following beneficial effects:

[0018] 1. The full-seal leak-proof oil extraction well head, by setting up the flow channel sealing device can provide liquid to the connection of the Christmas tree is surrounded by sealing, the whole sealing process using liquid sealing, realize the whole sealing of the Christmas tree, the principle is similar to the cover bowl type sealing of "sauerkraut jar", ensure the absolute sealing of the inner and outer layers, the liquid is set around the connection of each component of the pipe valve, then solidify with the room temperature liquid, produce solidification sealing layer, avoid the leakage of the inner and outer layers, so the oil leakage, can use the blocking effect of liquid solidification, realize the whole sealing of oil and gas, and this sealing method can improve the sealing effect of the oil circuit, and will not be limited by the use time, cause the sealing effect to reduce.

[0019] 2. The full-seal leak-proof oil extraction well head, by setting up the air charging sealing device can utilize the oil circuit inside the Christmas tree when flowing, use the internal flow force to push the piston to extrude, in turn, the hollow rubber pad is automatically inflated, and the inflated hollow rubber pad can ensure the more stable sealing of each connecting piece.

[0020] 3. The full-seal leak-proof oil extraction well head, by setting up the filter device can realize the preliminary filtration of the oil liquid during oil extraction, and utilize the oil flow force to convert into rotary force, drive the scraper to rotate and in turn automatically clean the bottom of the filter plate, avoid the filter plate from being blocked after long time use. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The whole structure schematic diagram of the full-seal leak-proof oil extraction well head is proposed in the application;

[0022] Figure 2 The whole bottom section structure schematic diagram of the full-seal leak-proof oil extraction well head is proposed in the application;

[0023] Figure 3 The flow channel sealing structure schematic diagram of the full-seal leak-proof oil extraction well head is proposed in the application;

[0024] Figure 4 The liquid storage pipe connecting structure schematic diagram of the full-seal leak-proof oil extraction well head is proposed in the application;

[0025] Figure 5 The air charging sealing device and filter device structure schematic diagram of the full-seal leak-proof oil extraction well head is proposed in the application;

[0026] Figure 6 The filter plate connecting structure schematic diagram of the full-seal leak-proof oil extraction well head is proposed in the application;

[0027] Figure 7A hollow rubber pad structure schematic diagram of a full sealing anti-leakage oil production well head is provided.

[0028] In the figure: 1, pipe valve; 2, casing part; 3, tubing part; 4, sealing assembly; 401, hollow sleeve; 402, flow channel groove; 403, deposition groove; 404, communication groove; 405, flow-through groove; 406, opening groove; 407, rubber pad; 408, bearing seat; 409, volume groove; 410, filling pipe; 411, liquid storage pipe; 412, branch pipe; 413, spacer; 414, extrusion spring; 415, impeller; 416, moving shaft; 417, filter plate; 418, piston cavity; 419, support rod; 420, piston sleeve; 421, filter hole; 422, air groove; 423, hollow rubber pad; 424, scraper; 425, extension spring; 426, long groove; 4231, rubber tube; 4232, inflation terminal; 5, slip hanger. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0030] Please refer to Figures 1-7 A full sealing anti-leakage oil production well head, comprising a pipe valve 1, a tubing part 3 is arranged below the pipe valve 1, a casing part 2 is connected to the bottom of the tubing part 3, a slip hanger 5 is arranged in the casing part 2, and a sealing assembly 4 is arranged on the tubing part 3; the sealing assembly 4 comprises a flow channel sealing device, an inflation sealing device and a filtering device; the flow channel sealing device is used to provide a liquid flow channel to achieve liquid solidification sealing of the pipe valve 1, the tubing part 3 and the casing part 2; the inflation sealing device uses the flow pressure of the pipe valve 1 to provide extrusion inflation type fastening sealing; and the filtering device is used to filter the oil liquid during oil production.

[0031] It is worth noting that the flow channel sealing device comprises a hollow sleeve 401 fixed on the surface of the pipe valve 1, the pipe valve 1 is internally provided with a flow channel groove 402, the oil pipe 3 is provided with a deposition groove 403, the deposition groove 403 is communicated with the hollow sleeve 401 through the flow channel groove 402, the oil pipe 3 is provided with a sealing gasket abutting against the pipe valve 1, and the sealing gasket is arranged outside the deposition groove 403. The surface of the oil pipe 3 is provided with a flow-through groove 405, the inside of the oil pipe 3 is provided with a communication groove 404, the flow-through groove 405 is communicated with the deposition groove 403 through the communication groove 404, the surface of the sleeve pipe 2 is provided with a plurality of rubber pads 407, and the plurality of rubber pads 407 are connected with the oil pipe 3. The top of the sleeve pipe 2 is provided with an opening groove 406 communicated with the flow-through groove 405, the inside of the pipe valve 1 is provided with a bearing seat 408, and the bearing seat 408 is provided with a volume groove 409. The sealing liquid in the hollow sleeve 401 flows, and the sealing liquid here can be a glue liquid insoluble in oil. When the glue liquid enters the inside of the hollow sleeve 401, it will flow into the inside of the deposition groove 403 through the flow channel groove 402. The deposition groove 403 is located at the connection position of the pipe valve 1 and the oil pipe 3, similar to the brim of the "sour cabbage jar", and is deposited. Then, after being arranged around the inside of the deposition groove 403, it will continue to flow to the position of the flow-through groove 405 through the arrangement of the communication groove 404. Under the same principle, after filling the flow-through groove 405, it will continue to flow to the position of the opening groove 406 for filling. When the opening groove 406 is filled, it will not continue to flow, but belongs to the bottom flow channel of the liquid. Therefore, the connection positions of the pipe valve 1, the sleeve pipe 2 and the oil pipe 3 are all wrapped by the liquid, and the absolute sealing of the inner and outer layers is guaranteed by the wrapping of the liquid. Then, as the overall room temperature decreases, the solidification wax sealing effect of the paraffin solution is guaranteed.

[0032] In the embodiment, the outer surface of the pipe valve 1 is provided with a liquid storage pipe 411, the liquid storage pipe 411 is communicated with a filling pipe 410, the filling pipe 410 is threadedly connected with a sealing cover, the liquid storage pipe 411 is communicated with the hollow sleeve 401 through a branch pipe 412, and the inside of the hollow sleeve 401 is provided with a colored sealing liquid. The setting of the liquid storage pipe 411 can provide a channel for internal liquid filling. Because the liquid will be consumed with the length of time, in order to avoid consumption, the filling pipe 410 is arranged to fill the solution in the inside. The sealing liquid is not limited to paraffin, but can also be a relatively viscous glue liquid, which has a certain solidification effect or is in a solid-liquid mixed state to achieve the sealing effect. The sealing principle is similar to the pickling principle of the "sour cabbage jar". The solution is arranged at the brim, and then the solidification wax sealing is realized to achieve the overall stability sealing. Compared with the traditional sealing technology, the sealing effect of the technology is better, and the connection sealing of multiple nodes of the Christmas tree can be realized.

[0033] Furthermore, the air-filled sealing device includes an impeller 415. A baffle 413 is connected to the top of the impeller 415 via a compression spring 414. The baffle 413 is fixed inside the valve 1. A movable shaft 416 is fixedly connected to the center of the impeller 415. A filter plate 417 is mounted on the movable shaft 416. A piston sleeve 420 is connected to the filter plate 417 via multiple support rods 419. A piston chamber 418 is provided inside the valve 1. The piston sleeve 420 is slidably connected inside the piston chamber 418. An air groove 422 is provided inside the valve 1. One end of the air groove 422 is connected to a hollow rubber gasket 423, and the other end of the air groove 422 communicates with the piston chamber 418. The hollow rubber gasket 423 includes a rubber tube 4231. An air-filled terminal 4232 is provided on the rubber tube 4231. The air-filled terminal 4232 communicates with the bottom of the air groove 422. The rubber tube 4231 is secured at the connection between the valve 1 and the oil pipe fitting 3. Utilizing the flow of oil during the suction process, the filter plate 417 is positioned in the middle of the flow channel, causing it to rise to a certain height. Subsequently, multiple support rods 419 drive the piston sleeve 420 to rise, creating a piston movement. This squeezes the airflow inside the piston chamber 418, expelling it from the air groove 422 and into the inflation terminal 4232. The air pressure is gradually injected into the hose 4231, causing it to expand. The expanded hose 4231 then fits more tightly against the connection between the valve 1 and the sleeve fitting 2. Therefore, even with higher internal oil suction pressure, the expansion effect results in a tighter seal.

[0034] Furthermore, the filtration device includes a telescopic spring 425, with a scraper 424 connected to the top of the telescopic spring 425 and the bottom of the telescopic spring 425 connected to the support base 408. The surface of the scraper 424 abuts against the bottom of the filter plate 417, and filter holes 421 are provided on the filter plate 417. By setting up a filtration device, the oil is initially filtered during extraction. Since the oil flows from bottom to top when it is extracted from the ground, the filter holes 421 are used to perform initial filtration in the oil flow channel. Afterwards, as the oil flows, it will pass through the impeller 415 and drive the impeller 415 to rotate. The scraper 424 is slidably connected to the moving shaft 416. So when the filter plate 417 moves upward, the elastic force of the telescopic spring 425 pushes the scraper 424 to always abut against the bottom of the filter plate 417. The rotation of the impeller 415 will synchronously drive the rotation of the moving shaft 416, and the moving shaft 416 will synchronously drive the rotation of the scraper 424, thereby controlling the scraper 424 to rotate and clean the impurities attached to the bottom of the filter plate 417. The cleaned impurities will gradually flow down the slope into the interior of the volume tank 409.

[0035] Furthermore, the bottom of the filter plate 417 has a conical structure, and an elongated groove 426 is formed on the surface of the moving shaft 416. The scraper 424 is slidably connected to the elongated groove 426. Through the elongated groove 426, after the filter plate 417 moves upward, the scraper 424 slides on the elongated groove 426, and the elastic force of the telescopic spring 425 controls the scraper 424 to always be at the bottom of the filter plate 417 to form abutment contact.

[0036] Working principle: When the entire wellhead is in use, the sealing fluid inside the hollow sleeve 401 flows. Specifically, the sealing fluid can be set as an oil-insoluble adhesive. When the adhesive enters the interior of the hollow sleeve 401, it flows into the sedimentation tank 403 through the flow channel 402. The sedimentation tank 403 is located at the connection between the valve 1 and the tubing fitting 3, similar to the brim of a "sauerkraut jar," where sediment is deposited. After being filled inside the entire sedimentation tank 403, it continues to flow through the connecting channel 404 to the flow channel 405. Under the same principle, after the flow channel 405 is filled, it continues to flow to the open channel 406 and is filled. When the open channel 406 is filled, it stops flowing and becomes the bottom flow channel of the liquid. Therefore, the connection points of the entire valve 1, sleeve fitting 2, and tubing fitting 3 are all surrounded by liquid, which ensures absolute sealing of the inner and outer layers. In this scheme, a paraffin solution is used as the sealing fluid. Initially, the paraffin solution needs to be heated to a liquid state. Then, the paraffin solution is injected from the storage pipe 411 through the opening of the injection pipe 410. It flows into the interior of the hollow sleeve 401 through the branch pipe 412, and then gradually enters the interior of each slot through the aforementioned flow channels. As the outdoor temperature decreases, the paraffin solution will gradually solidify, forming a "wax seal" process. Therefore, by utilizing the connectivity of the flow channels, a "wax seal" is achieved at the overall mating points of multiple connectors, thus achieving an absolute seal of the wellhead. Furthermore, the entire device is equipped with an air-filled sealing system. Utilizing the flow during oil extraction, the filter plate 417, positioned in the middle of the flow channel, will rise to a certain height. Multiple support rods 419 then drive the piston sleeve 420 upwards, creating piston movement. This compresses the airflow inside the piston chamber 418, forcing it out from the air groove 422 and into the air-filled terminal 4232. The air pressure is gradually injected into the hose 4231, causing it to expand. The expanded hose 4231 then fits more tightly against the connection between the valve 1 and the sleeve fitting 2. Therefore, even with higher internal oil extraction pressure, the expansion effect results in a tighter seal. This further improves the overall sealing performance, forming a triple-seal effect: traditional "gasket seal," a special "liquid-curing wax seal," and finally, an "air-filled expansion seal," maximizing the complete sealing of the wellhead.Furthermore, the entire device is equipped with a filtration system to perform preliminary filtration of the oil during extraction. Since the oil flows from bottom to top when extracted from the ground, the filter holes 421 are used to perform preliminary filtration in the oil flow channel. Afterward, as the oil flows, it will pass through the impeller 415 and drive the impeller 415 to rotate. The scraper 424 is slidably connected to the moving shaft 416. Therefore, when the filter plate 417 moves upward, the elastic force of the telescopic spring 425 pushes the scraper 424 to always abut against the bottom of the filter plate 417. The rotation of the impeller 415 will synchronously drive the rotation of the moving shaft 416, which in turn drives the rotation of the scraper 424. This controls the scraper 424 to rotate and clean the impurities attached to the bottom of the filter plate 417. The cleaned impurities will gradually flow down the slope into the interior of the volume tank 409 for temporary storage, and will be removed and cleaned during subsequent maintenance and repair.

[0037] If disassembly and maintenance are required, simply heat the exterior of the wellhead tree to reliquefy the sealant. Then, loosen the bolts at the connections. Each node of the wellhead tree can be sealed using the sealing structure of this technical solution, achieving a complete connection and seal to the wellhead. It should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A fully sealed, leak-proof oil wellhead, characterized in that, include A pipe valve (1) is provided below the pipe valve (1), and an oil pipe fitting (3) is installed below the oil pipe fitting (3). A sleeve fitting (2) is connected to the bottom of the oil pipe fitting (3). A slip hanger (5) is provided inside the sleeve fitting (2). A sealing assembly (4) is provided on the oil pipe fitting (3). The sealing assembly (4) includes a flow channel sealing device, an air-filling sealing device, and a filtration device; The flow channel sealing device is used to provide liquid flow channel to achieve liquid solidification sealing for the pipe valve (1), oil pipe fitting (3) and sleeve fitting (2); The inflatable sealing device utilizes the flow pressure of the pipe valve (1) to provide a squeeze-inflatable fastening seal; The filtration device is used to filter the oil during oil extraction. The flow channel sealing device includes a hollow sleeve (401), which is fixed on the surface of the pipe valve (1). The pipe valve (1) has a flow channel groove (402) inside, and the oil pipe fitting (3) has a sedimentation groove (403). The sedimentation groove (403) is connected to the hollow sleeve (401) through the flow channel groove (402). The surface of the oil pipe fitting (3) is provided with a flow groove (405), and the interior of the oil pipe fitting (3) is provided with a connecting groove (404). The flow groove (405) is connected to the sedimentation tank (403) through the connecting groove (404). The top of the sleeve fitting (2) is provided with an opening groove (406), and the opening groove (406) is connected to the flow groove (405).

2. The fully sealed, leak-proof oil wellhead according to claim 1, characterized in that: The oil pipe fitting (3) is provided with a sealing gasket, which abuts against the pipe valve (1) and is located on the outside of the sedimentation tank (403).

3. The fully sealed, leak-proof oil wellhead according to claim 2, characterized in that: The surface of the sleeve (2) is provided with a plurality of rubber pads (407), and the plurality of rubber pads (407) are connected to the oil pipe (3).

4. The fully sealed, leak-proof oil wellhead according to claim 3, characterized in that: The valve (1) has a support seat (408) installed inside, and a volume groove (409) is provided above the support seat (408).

5. A fully sealed, leak-proof oil wellhead according to claim 2, characterized in that: The outer surface of the valve (1) is provided with a liquid storage pipe (411), and a filling pipe (410) is connected to the liquid storage pipe (411). A sealing cap is threaded onto the filling pipe (410). The liquid storage pipe (411) is connected to the hollow sleeve (401) through a branch pipe (412). The hollow sleeve (401) is filled with a colored sealing liquid.

6. The fully sealed, leak-proof oil wellhead according to claim 4, characterized in that: The inflatable sealing device includes an impeller (415), the top of which is connected to a partition (413) via a compression spring (414). The partition (413) is fixed inside the pipe valve (1). A movable shaft (416) is fixedly connected to the center of the impeller (415). A filter plate (417) is mounted on the movable shaft (416). A piston sleeve (420) is connected to the filter plate (417) via multiple support rods (419). A piston chamber (418) is provided inside the pipe valve (1). The piston sleeve (420) is slidably connected inside the piston chamber (418). An air groove (422) is provided inside the pipe valve (1). A hollow rubber pad (423) is connected to one end of the air groove (422). The other end of the air groove (422) is connected to the piston chamber (418).

7. A fully sealed, leak-proof oil wellhead according to claim 6, characterized in that: The hollow rubber pad (423) includes a rubber tube (4231), on which an inflation terminal (4232) is provided. The inflation terminal (4232) is connected to the bottom of the air groove (422), and the rubber tube (4231) is clamped at the connection between the pipe valve (1) and the oil pipe fitting (3).

8. A fully sealed, leak-proof oil wellhead according to claim 6, characterized in that: The filtration device includes a telescopic spring (425), a scraper (424) is connected to the top of the telescopic spring (425), the bottom of the telescopic spring (425) is connected to the support seat (408), the surface of the scraper (424) abuts against the bottom of the filter plate (417), and the filter plate (417) is provided with filter holes (421).

9. A fully sealed, leak-proof oil wellhead according to claim 8, characterized in that: The bottom of the filter plate (417) is conical, and the surface of the moving shaft (416) is provided with a long groove (426), and the scraper (424) is slidably connected to the long groove (426).

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