Jet pump

Abstract

The utility model relates to the technical field of jet pumps, in particular to a jet pump which comprises a casing pipe, an oil pipe and a pump cylinder, a pump core is arranged inside the pump cylinder, a metal corrugated pipe is sleeved on the outer surface of the pump core, the outer surface of the metal corrugated pipe is connected with the inner wall of the pump cylinder in a clamping mode, a packer is arranged at one end of the casing pipe, and the other end of the casing pipe is connected with the oil pipe. One end of the pump cylinder is detachably connected with the upper end of the packer, and a buffering rubber pad is arranged on the end face, making contact with the packer, of the pump cylinder. According to the jet pump, through matched arrangement of the pump core and the metal corrugated pipe, when the jet pump is used, the metal corrugated pipe structure not only can provide elastic support for the pump core and effectively compensate radial displacement between the pump core and the pump cylinder, but also can remarkably absorb vibration energy generated by fluid flow nonuniformity and pressure pulsation; accurate positioning and reliable sealing of the pump core assembly are guaranteed, the pump core assembly can be protected, and meanwhile noise generated by vibration can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of jet pumps, in particular to a jet pump. Background Art

[0002] Against the backdrop of global energy transformation, the supply and demand structure of oil and gas resources is undergoing profound changes. As the exploration and development of conventional oil and gas resources continues to deepen, resource reserves are decreasing year by year, and development costs continue to rise. Under this situation, the development of unconventional oil and gas resources represented by tight gas is gradually becoming a key breakthrough for the oil and gas industry to ensure energy supply.

[0003] In the development of high-water-content gas reservoirs, the decline in the natural liquid-carrying capacity of gas wells has become a core problem restricting efficient extraction. Specifically, the natural liquid-carrying period of Class II gas wells can only last for 180 days, while Class III gas wells completely lose their natural liquid-carrying function (natural liquid-carrying period is 0 days), resulting in continuous accumulation of formation liquid, seriously inhibiting the release of gas reservoir production capacity. The current mainstream water drainage and gas production technologies such as bubble drainage, plunger, and velocity tube are significantly less adaptable in high-water-content areas, with the technical efficiency rate falling below 50%. The bottleneck of traditional technology directly leads to the inability of traditional processes to meet the continuous strong drainage demand of high-water-content gas reservoirs with a daily drainage volume of more than 50m³. Especially when facing complex working conditions with large fluctuations in liquid production and low gas-liquid ratio, problems such as increased equipment wear and a sudden drop in drainage efficiency often occur. Against this background, jet pumps, with their technical characteristics of no downhole moving parts, sand erosion resistance, and adaptability to large-volume liquid drainage, have become the core solution to break through the existing development dilemma.

[0004] However, the existing technology has the following problems when it is actually used:

[0005] Due to the unevenness of fluid flow and pressure pulsation, the existing jet pump is prone to vibration during operation. Long-term and severe vibration can easily lead to loosening of equipment connectors and fatigue damage of components, thereby affecting the stability and safety of the connection between the jet pump and external pipeline equipment. At the same time, the vibration of the jet pump is prone to generate large noise. Utility Model Content

[0006] (1) Technical problems solved

[0007] In order to overcome the above-mentioned defects of the prior art, the present utility model provides a jet pump, which solves the problem raised in the above background technology that the existing jet pump is prone to vibration during operation due to the unevenness of fluid flow and pressure pulsation, and long-term severe vibration is likely to cause loosening of equipment connectors and fatigue damage of components, thereby affecting the stability and safety of the connection between the jet pump and external pipeline equipment. At the same time, the jet pump is prone to generate large noise during vibration.

[0008] (2) Technical solution

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions: a jet pump, comprising a casing, an oil pipe and a pump barrel, a pump core is arranged inside the pump barrel, the outer surface of the pump core is sleeved with a metal bellows, the outer surface of the metal bellows is clamped with the inner wall of the pump barrel, a packer is provided at one end of the casing, one end of the pump barrel is detachably connected to the upper end of the packer, a buffer rubber pad is provided on the end faces of the pump barrel and the packer that contact each other, and a bottom valve is detachably connected to the inner wall of the packer.

[0010] Preferably, the pump core includes a fishing head and a liquid inlet pipe, the outer surface of the liquid inlet pipe is sleeved with a lifting leather cup, and a plurality of power liquid inlets are opened on the side of the liquid inlet pipe close to the fishing head, and the plurality of power liquid inlets are arranged in a circular array around the axis of the liquid inlet pipe.

[0011] Preferably, the other end of the liquid inlet pipe is detachably connected to a nozzle sleeve, a nozzle is provided inside the nozzle sleeve, and a plurality of formation fluid inlets are opened on the side of the nozzle sleeve close to the nozzle, and the plurality of formation fluid inlets are arranged in a circular array around the axis of the nozzle sleeve.

[0012] Preferably, the other end of the nozzle sheath is detachably connected to a throat sheath, and the interior of the throat sheath is provided with a throat pipe and a diffuser in sequence along the length direction.

[0013] Preferably, the other end of the throat sheath is detachably connected to a lower joint, a mixed liquid outlet is provided on one side of the middle portion of the lower joint, and sealing rings are sleeved on the outer surfaces of both ends of the lower joint.

[0014] Preferably, the number of the metal bellows is two, and the two metal bellows are symmetrically arranged with the width center line of the pump core as the symmetry axis.

[0015] Preferably, a crude oil flow channel is provided inside the pump barrel, and a discharge port is provided on a side of the pump barrel close to the packer.

[0016] Preferably, a mixed liquid flow channel is opened inside the sleeve.

[0017] (3) Beneficial effects

[0018] The utility model provides a jet pump, which has the following beneficial effects:

[0019] This jet pump, through the coordinated arrangement of the pump core and the metal bellows, not only provides elastic support for the pump core during operation, effectively compensating for radial displacement between the pump core and the pump barrel, but also significantly absorbs vibration energy generated by fluid flow unevenness and pressure pulsation, ensuring accurate positioning and reliable sealing of the pump core assembly, protecting the pump core assembly, and reducing noise generated by vibration. The provision of a buffer rubber pad can facilitate the buffering of impact forces generated during downhole operations, compensate for installation errors between components, improve connection sealing, reduce direct friction between metal components, and further extend service life. At the same time, the provision of a packer can accurately isolate the annular space between the casing and the tubing, effectively separating different pressure zones, avoiding interlayer fluid crossflow interference, and ensuring the stability of the drainage process. The provision of a bottom valve on the inner wall of the packer automatically closes due to the loss of negative pressure when the pump body stops working, effectively preventing backflow of formation fluid, maintaining stable pressure in the pump to provide initial pressure conditions for restarting, and preventing pump core blockage caused by backflow of impurities such as sand. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of the utility model;

[0021] Figure 2 This is a schematic diagram of the pump core structure of the utility model.

[0022] In the figure: 1. casing; 2. oil pipe; 3. pump barrel; 4. pump core; 401. fishing head; 402. liquid inlet pipe; 403. lifting leather cup; 404. power fluid inlet; 405. nozzle sleeve; 406. nozzle; 407. formation fluid inlet; 408. throat sleeve; 409. throat; 410. diffuser; 411. lower joint; 412. mixed liquid outlet; 413. sealing ring; 5. metal bellows; 6. packer; 7. buffer rubber pad; 8. bottom valve; 9. crude oil flow channel; 10. discharge outlet; 11. mixed liquid flow channel. DETAILED DESCRIPTION

[0023] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] Embodiment 1;

[0025] See also Figure 1 and Figure 2The utility model provides a technical solution: a jet pump, which is mainly used in the scene of high water-content gas wells, including casing 1, oil pipe 2 and pump barrel 3. A pump core 4 is arranged inside the pump barrel 3, and a metal bellows 5 is sleeved on the outer surface of the pump core 4. The pump core 4 includes a fishing head 401 and a liquid inlet pipe 402. The outer surface of the liquid inlet pipe 402 is sleeved with a lifting leather cup 403. A plurality of power liquid inlet ports 404 are opened on the side of the liquid inlet pipe 402 close to the fishing head 401. The plurality of power liquid inlet ports 404 are arranged in a ring array around the axis of the liquid inlet pipe 402. The other end of the liquid inlet pipe 402 is detachably connected to a nozzle sheath 405. A nozzle 406 is provided inside the nozzle sheath 405. A plurality of formation fluid inlets 407 are provided on one side of the nozzle sheath 405 near the nozzle 406. The plurality of formation fluid inlets 407 are arranged in a circular array around the axis of the nozzle sheath 405. A throat sheath 408 is detachably connected to the other end of the nozzle sheath 405. A throat pipe 409 and a diffuser 410 are sequentially provided inside the throat sheath 408 along its length. A lower joint 411 is detachably connected to the other end of the throat sheath 408. A mixed liquid outlet 412 is provided on one side of the middle portion of the lower joint 411. Sealing rings 413 are sleeved on the outer surfaces of both ends of the lower joint 411.

[0026] Through the above technical solution, when in use, the oil pipe 2, pump barrel 3 and pump core 4 are installed in sequence inside the casing 1, and an annular channel is formed between the oil pipe 2 and the pump barrel 3 as a power fluid injection channel. A larger annular space is formed between the oil pipe 2 and the casing 1 as a mixed liquid discharge channel. The high-pressure power fluid flows downward through the annular channel between the oil pipe 2 and the pump barrel 3, flows into the interior of the pump core 4, and enters the interior of the liquid inlet pipe 402 through the power fluid inlet port 404 on the outer surface of the liquid inlet pipe 402 inside the pump core 4, and is sent into the interior of the nozzle 406. The nozzle 406 accelerates the high-pressure power fluid to form a high-speed jet, generating negative pressure. At the same time, the power fluid inlet port 404 is distributed in a ring array, which can ensure that the high-pressure power fluid enters evenly. After the negative pressure is formed at the nozzle 406, the external formation fluid can be sucked into the nozzle 406 through the formation fluid inlet 407 and sent into the throat 409 for mixing. At the same time, the throat 409 can provide a mixing space for the power fluid and the formation fluid, realize energy transfer through momentum exchange, and the mixed liquid enters the diffuser 410. The diffuser 410 decelerates and pressurizes the mixed liquid to increase its discharge pressure. The pressurized liquid is discharged through the mixed liquid outlet 412 on the side of the lower joint 411. At the same time, the sealing rings 413 on the outer surfaces of both ends of the lower joint 411 can ensure that the lower joint 411 is sealed with the inner wall of the pump barrel 3 to prevent fluid leakage.

[0027] Embodiment 2;

[0028] See also Figure 1 and Figure 2The utility model provides a technical solution based on the first embodiment. The outer surface of the metal bellows 5 is clamped with the inner wall of the pump barrel 3. There are two metal bellows 5. The two metal bellows 5 are symmetrically arranged with the width center line of the pump core 4 as the symmetry axis. A crude oil flow channel 9 is opened inside the pump barrel 3. A discharge port 10 is opened on the side of the pump barrel 3 close to the packer 6. A mixed liquid flow channel 11 is opened inside the casing 1. A packer 6 is provided at one end of the casing 1. One end of the pump barrel 3 is detachably connected to the upper end of the packer 6. A buffer rubber pad 7 is provided on the end surface where the pump barrel 3 and the packer 6 contact each other. The inner wall of the packer 6 is detachably connected to a bottom valve 8.

[0029] Through the above technical solution, when the high-pressure power fluid passes through the nozzle 406, it is accelerated to a high-speed state through the contraction-type flow channel, and a stable negative pressure zone is formed at the outlet of the nozzle 406. At this time, a pressure difference is formed between the formation fluid inlet 407 and the crude oil flow channel 9. The negative pressure difference inside the crude oil flow channel 9 drives the bottom valve 8 to open, so that the crude oil at the lower end of the packer 6 enters the interior of the crude oil flow channel 9 through the bottom valve 8, and is then sucked into the throat pipe 409 inside the pump core 4. The two fluids complete momentum exchange through turbulent diffusion in the throat pipe 409. After the mixed liquid is decelerated and pressurized by the diffuser 410, it enters the mixed liquid flow channel 11 in the casing 1 through the discharge port 10 outside the pump barrel 3, and is finally discharged from the interior of the surface pipeline.

[0030] In the present invention, the working steps of the device are as follows:

[0031] First, the casing 1 is installed to the bottom of the artificial well, and then the oil pipe 2, pump barrel 3 and pump core 4 are installed in the casing 1 in sequence. The ground equipment is started, and high-pressure power fluid is injected into the oil pipe 2. The power fluid flows downward through the annular channel of the oil pipe 2 and the pump barrel 3, and evenly enters the interior of the inlet pipe 402 through the power fluid inlet 404 on the outer surface of the inlet pipe 402. The high-pressure power fluid flows through the contraction flow channel of the nozzle 406 and is accelerated into a high-speed jet. The high-speed jet forms a low-pressure area at the outlet of the nozzle 406, generating suction. The negative pressure at the nozzle 406 is transmitted to the formation fluid inlet 407, so that a pressure difference is formed in the crude oil flow channel 9. The pressure difference pushes the bottom valve 8 to open, opening the channel. The formation fluid passes through the bottom valve 8 at the lower end of the packer 6 and is pumped into the formation fluid inlet 407 after passing through the crude oil flow channel 9. 407 is sucked in, and the formation fluid and the high-speed power fluid are mixed in the throat pipe 409, and momentum exchange is achieved through turbulent diffusion. The mixing process is stabilized by the equal-diameter section of the throat pipe 409 to ensure sufficient mixing. Then the mixed liquid enters the diffuser 410, the cross-sectional area of ​​the flow channel gradually expands, the flow velocity decreases, the kinetic energy is converted into pressure energy, and the pressure of the mixed liquid is significantly increased to overcome the wellbore back pressure. The pressurized mixed liquid is discharged laterally through the mixed liquid outlet 412 of the lower joint 411, and the mixed liquid enters the discharge port 10 on the outside of the pump barrel 3 and merges into the mixed liquid flow channel 11 in the casing 1. Finally, the mixed liquid is returned to the surface pipeline along the annular space of the oil pipe 2 and the casing 1. After the power fluid injection is stopped, the negative pressure at the nozzle 406 disappears, and the bottom valve 8 is automatically closed to prevent the formation fluid from backflowing and maintain the pressure in the pump.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A jet pump comprising a casing (1), an oil pipe (2) and a pump barrel (3), characterized in that: A pump core (4) is provided inside the pump barrel (3), and a metal bellows (5) is sleeved on the outer surface of the pump core (4). The outer surface of the metal bellows (5) is clamped with the inner wall of the pump barrel (3). A packer (6) is provided at one end of the sleeve (1), and one end of the pump barrel (3) is detachably connected to the upper end of the packer (6). The contacting end surfaces of the pump barrel (3) and the packer (6) are provided with a buffer rubber pad (7), and the inner wall of the packer (6) is detachably connected to a bottom valve (8).

2. The jet pump according to claim 1, characterized in that: The pump core (4) comprises a fishing head (401) and a liquid inlet pipe (402). The outer surface of the liquid inlet pipe (402) is sleeved with a lifting leather cup (403). A plurality of power liquid inlet ports (404) are provided on a side of the liquid inlet pipe (402) close to the fishing head (401). The plurality of power liquid inlet ports (404) are arranged in a circular array around the axis of the liquid inlet pipe (402).

3. The jet pump according to claim 2, characterized in that: The other end of the liquid inlet pipe (402) is detachably connected to a nozzle sleeve (405), a nozzle (406) is provided inside the nozzle sleeve (405), and a plurality of formation fluid inlets (407) are provided on a side of the nozzle sleeve (405) close to the nozzle (406), and the plurality of formation fluid inlets (407) are arranged in a circular array around the axis of the nozzle sleeve (405).

4. The jet pump according to claim 3, characterized in that: The other end of the nozzle sheath (405) is detachably connected to a throat sheath (408), and a throat (409) and a diffusion tube (410) are sequentially arranged inside the throat sheath (408) along the length direction.

5. The jet pump according to claim 4, characterized in that: The other end of the throat sheath (408) is detachably connected to a lower joint (411), a mixed liquid outlet (412) is provided on one side of the middle portion of the lower joint (411), and sealing rings (413) are sleeved on the outer surfaces of both ends of the lower joint (411).

6. The jet pump according to claim 1, characterized in that: The number of the metal bellows (5) is two, and the two metal bellows (5) are symmetrically arranged with the width center line of the pump core (4) as the symmetry axis.

7. The jet pump according to claim 1, characterized in that: A crude oil flow channel (9) is provided inside the pump barrel (3), and a discharge port (10) is provided on a side of the pump barrel (3) close to the packer (6).

8. The jet pump according to claim 1, characterized in that: A mixed liquid flow channel (11) is provided inside the sleeve (1).

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