Self-adaptive plunger

Abstract

The invention belongs to the technical field of petroleum and natural gas exploitation, and discloses a self-adaptive plunger which comprises a plunger body, a valve seat and a floating valve body, a channel is formed in the plunger body, an exhaust hole communicated with the channel is formed in the upper end of the plunger body, a bypass hole is formed in the side wall of the bottom end of the plunger body, the channel comprises a large-diameter section and a small-diameter section, the exhaust hole is connected with the small-diameter section, and the bypass hole is communicated with the valve seat. The bypass hole is communicated with the large-diameter section; the valve seat is arranged at the bottom end of the plunger body, and a through hole is formed in the valve seat so as to be communicated with the large-diameter section; the floating valve body is arranged in the large-diameter section in an up-down moving mode, the floating valve body has a floating state and a descending state which are mutually switched, and when the floating valve body is in the floating state, the floating valve body blocks a connecting opening of the small-diameter section and the large-diameter section and the through hole so that the small-diameter section and the large-diameter section can be isolated; in the descending state, the floating valve body opens the connecting port of the small-diameter section and the large-diameter section and the through hole so that the small-diameter section and the large-diameter section can be communicated. Downward movement resistance of the plunger can be reduced, downward movement time is shortened, and the production efficiency of water drainage and gas production of the plunger is improved.

Description

Technical Field

[0001] The invention relates to the technical field of oil and natural gas exploitation, and in particular to an adaptive plunger. Background Art

[0002] As a safe, efficient, and environmentally friendly green energy, natural gas is an indispensable component of my country's and the world's energy. However, during the natural gas extraction process, formation water will have a significant impact on production. If the accumulated liquid in the wellbore is not discharged in time, as the height of the accumulated liquid increases, the production of the natural gas well will decrease rapidly until it stops. In severe cases, the corrosive substances contained in the accumulated liquid will corrode the downhole equipment and pipelines, causing equipment damage and shortening its life. The solid particles contained in the accumulated liquid may also block the equipment and pipelines.

[0003] Plunger gas lift is a simple and efficient method of draining liquid and producing gas. It is a special form of intermittent gas lift. The plunger, as a solid sealing interface, separates the lifting gas and the lifted liquid, reduces gas crossflow and liquid fallback, and improves the efficiency of lifting gas. The energy of plunger gas lift mainly comes from the formation, but when the formation gas energy is insufficient, a certain amount of high-pressure gas needs to be injected into the well. The high-pressure gas pushes the plunger and the liquid above it from the bottom of the well to the wellhead, removes the liquid at the bottom of the well, increases the production pressure difference, and prolongs the production time of the gas well. For wells where conventional continuous gas lift or intermittent gas lift is inefficient, plunger gas lift can improve production efficiency and avoid ineffective consumption of gas.

[0004] In the prior art, when the plunger falls in the oil pipe, the falling speed becomes very slow due to the friction of the inner wall of the oil pipe, the resistance of the gas and the lifting force, which causes the plunger to fall for a large part of the production cycle, seriously affecting the production efficiency. Summary of the invention

[0005] The object of the present invention is to provide an adaptive plunger, which can reduce the resistance of the plunger when it is descending, shorten the descending time, and improve the production efficiency of the plunger in draining water and recovering gas.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] The adaptive plunger comprises a plunger body, a passage is arranged in the plunger body, an exhaust hole is arranged at the upper end of the plunger body, and a bypass hole is arranged on the side wall of the bottom end of the plunger body.

[0008] The channel includes a large diameter section and a small diameter section, the exhaust hole is connected to the small diameter section, and the bypass hole is connected to the large diameter section;

[0009] The adaptive plunger also includes a valve seat and a floating valve body. The valve seat is arranged at the bottom end of the plunger body. A through hole is arranged on the valve seat to be connected to the large diameter section. The floating valve body moves up and down and is arranged in the large diameter section.

[0010] The floating valve body has a floating state and a descending state that can be switched with each other. When in the floating state, the floating valve body blocks the connecting port between the small diameter section and the large diameter section and the through hole to isolate the two; when in the descending state, the floating valve body opens the connecting port between the small diameter section and the large diameter section and the through hole to connect the two.

[0011] Preferably, the valve seat has a hollow cavity, the hollow cavity is connected to the large diameter section, the through hole is connected to the hollow cavity, and part of the floating valve body slides in the hollow cavity to isolate the through hole from the hollow cavity.

[0012] Preferably, a radial groove is provided on the top of the valve seat, and the radial groove extends from the side wall of the valve seat to the hollow cavity groove, and the opening of one end of the through hole is arranged in the radial groove, and the other end passes through the valve seat downward.

[0013] Preferably, a plurality of radial grooves are arranged at intervals along the circumferential direction of the hollow cavity groove.

[0014] Preferably, the floating valve body comprises a float and a valve core, the float is connected to the bottom of the valve core, the valve core is movably disposed in the hollow cavity, and the float is provided with a through hole penetrating up and down.

[0015] Preferably, one of the hollow cavity and the float is provided with a guide groove, and the other is provided with a guide key that is slidably connected with the guide groove.

[0016] Preferably, the valve core is divided into an upper body and a lower body, the upper body is cylindrical, and the lower body is truncated cone-shaped, and the top surface of the truncated cone faces the float.

[0017] Preferably, the outer diameter of the valve core is smaller than the inner diameter of the large diameter section.

[0018] Preferably, the floating valve body further comprises a connecting rod, one end of which is connected to the valve core, and the other end of which is connected to the floating body, so that the valve core and the floating body are connected at an interval.

[0019] Preferably, the valve core is a hollow body.

[0020] Beneficial effects of the present invention:

[0021] Through the floating valve body moving in the large diameter section, when the plunger is located below the liquid surface, the liquid enters the channel through the bypass hole and the through hole, and the floating valve body is in a floating state due to the buoyancy, and the floating valve body blocks the connection port and the through hole between the small diameter section and the large diameter section to isolate the two. When the pressure continues to increase, the plunger lifts the accumulated liquid upward; and when the plunger reaches the wellhead, the liquid in the channel is discharged out of the well through the bypass hole; then the floating valve body switches to a descending state, and the floating valve body descends due to the action of gravity, and the floating valve body opens the connection port and the through hole between the small diameter section and the large diameter section to connect the two, and the gas below the plunger is discharged from the exhaust hole through the through hole and the channel, thereby reducing the downward resistance of the plunger and realizing the rapid drop of the plunger to the liquid surface for a circulation cycle, thereby shortening the descending time and improving the plunger drainage and gas production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional view of the floating valve body in the adaptive plunger of the present invention when it is in a floating state;

[0023] Figure 2 It is a cross-sectional view of the floating valve body in the adaptive plunger of the present invention when it is in a descending state;

[0024] Figure 3 It is a schematic diagram of the three-dimensional structure of the floating valve body in the adaptive plunger of the present invention;

[0025] Figure 4 It is a schematic diagram of the three-dimensional structure of the valve seat in the adaptive plunger of the present invention.

[0026] In the figure:

[0027] 1. plunger body; 11. channel; 111. large diameter section; 112. small diameter section; 12. exhaust hole; 13. bypass hole;

[0028] 2. Valve seat; 21. Through hole; 22. Hollow cavity groove; 23. Radial groove;

[0029] 3. floating valve body; 31. floating body; 32. valve core; 321. upper body; 322. lower body; 33. connecting rod; 34. through hole;

[0030] 4. Guide groove;

[0031] 5. Guide key. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0033] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0035] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0036] like Figures 1 to 4 As shown, the present application provides an adaptive plunger, which includes a plunger body 1, a valve seat 2 and a floating valve body 3. A channel 11 is arranged in the plunger body 1, an exhaust hole 12 connected to the channel 11 is arranged at the upper end of the plunger body 1, and a bypass hole 13 is arranged on the side wall of the bottom end of the plunger body 1 to connect to the channel 11. The channel 11 includes a large diameter section 111 and a small diameter section 112, the exhaust hole 12 is connected to the small diameter section 112, and the bypass hole 13 is connected to the large diameter section 111; the valve seat 2 is arranged at the bottom end of the plunger body 1, A through hole 21 is provided on the valve seat 2 to enable communication with the large diameter section 111; the floating valve body 3 is arranged in the large diameter section 111 to move up and down, and the floating valve body 3 has a floating state and a descending state that can be switched with each other. When in the floating state, the floating valve body 3 blocks the connection port of the small diameter section 112 and the large diameter section 111 and the through hole 21 to isolate the two; when in the descending state, the floating valve body 3 opens the connection port of the small diameter section 112 and the large diameter section 111 and the through hole 21 to communicate with the two.

[0037] By the floating valve body 3 moving in the large diameter section 111, when the plunger is located below the liquid surface, the liquid enters the channel 11 through the bypass hole 13 and the through hole 21, and the floating valve body 3 floats up due to the buoyancy and is in a floating state. The floating valve body 3 blocks the connection port and the through hole 21 between the small diameter section 112 and the large diameter section 111 to isolate the two. When the pressure continues to increase, the plunger lifts the accumulated liquid upward; and when the plunger reaches the wellhead, the liquid in the channel 11 is discharged out of the well through the bypass hole 13; then the floating valve body 3 is converted to a descending state, and the floating valve body 3 descends due to the gravity. The floating valve body 3 opens the connection port and the through hole 21 between the small diameter section 112 and the large diameter section 111 to connect the two, and the gas below the plunger is discharged from the exhaust hole 12 through the through hole 21 and the channel 11, thereby reducing the downward resistance of the plunger and realizing the rapid drop of the plunger to the liquid surface for a circulation cycle, thereby shortening the descending time and improving the plunger drainage and gas production efficiency.

[0038] In this embodiment, the channel 11 passes through the lower end of the plunger body 1, and the valve seat 2 is installed on the lower end of the plunger body 1 by screws. The valve seat 2 is provided with a hollow cavity 22 connected with the large diameter section 111 of the channel 11, and the hollow cavity 22 extends downward from the top of the valve seat 2, and the through hole 21 is connected with the hollow cavity 22 and passes through the valve seat 2, so as to be able to connect the large diameter section 111 with the bottom of the plunger body 1, so that the gas under the plunger body 1 can be discharged through the through hole 21 and the channel 11 and then through the exhaust hole 12; and part of the floating valve body 3 is slidably arranged in the hollow cavity 22, so as to be able to isolate the through hole 21 and the hollow cavity 22. Specifically, a radial groove 23 is provided at the top of the valve seat 2, and the radial groove 23 extends from the side wall of the valve seat 2 to the hollow cavity 22, and one end of the through hole 21 is opened in the radial groove 23, and the other end downwardly penetrates the valve seat 2, so that when the floating valve body 3 slides in the hollow cavity 22, the outlet of the radial groove 23 in the hollow cavity 22 can be opened or closed, thereby indirectly blocking or opening the through hole 21. Further, a plurality of radial grooves 23 are provided, and the plurality of radial grooves 23 are arranged at intervals along the circumference of the hollow cavity 22, and each radial groove 23 is correspondingly provided with a through hole 21, so that the passing efficiency of gas or liquid can be increased.

[0039] In this embodiment, the floating valve body 3 includes a float 31 and a valve core 32, wherein the float 31 is connected to the lower end of the valve core 32, and the float 31 slides in the hollow cavity 22, so that the outlet of the radial groove 23 located in the hollow cavity 22 can be blocked or opened through the side of the float 31; illustratively, the size of the top of the valve core 32 is larger than the size of the connection port between the small diameter section 112 and the large diameter section 111, so that the connection port between the small diameter section 112 and the large diameter section 111 can be conveniently blocked during the movement of the valve core 32; and the float 31 is also provided with a through hole 34 that runs through the upper and lower ends, and the through hole 34 can connect the upper and lower end faces of the float 31, so that liquid or gas can pass through; for example, after the floating valve body 3 is in a descending state to the liquid surface, the liquid enters the through hole 21 into the through hole 34 of the float 31, so that it can pass through the through hole 34 to the upper end face of the float 31; in addition, the through hole 34 can also reduce the mass and facilitate floating.

[0040] Furthermore, in order to make the float 31 move more stably in the hollow cavity 22, one of the hollow cavity 22 and the float 31 is provided with a guide groove 4 in the up and down directions, and the other is provided with a guide key 5 that slides with the guide groove 4; in this embodiment, the guide groove 4 is provided in the hollow cavity 22, and the guide key 5 is provided on the float 31.

[0041] The floating valve body 3 further includes a connecting rod 33, one end of which is connected to the valve core 32, and the other end of which is connected to the float 31, so that the two are connected with a certain gap, so that when the float 31 is located at the lowest end in the hollow cavity 22, the radial groove 23 is located at the connecting rod 33, so that the liquid can enter the channel 11 more quickly from the through hole 21. Further, in order to facilitate the flow of liquid or gas from the bottom of the valve core 32 to the top of the valve core 32, the valve core 32 is divided into an upper body 321 and a lower body 322, the upper body 321 is cylindrical, and the lower body 322 is a truncated cone, the top surface of the truncated cone faces the float 31, so that the liquid or gas can pass through the surface of the truncated cone more quickly. Furthermore, the outer diameter of the valve core 32 is smaller than the inner diameter of the large diameter section 111, so that the liquid or gas can pass through the two sides of the valve core 32 more quickly, and then quickly enter the small diameter section 112 upward. In this embodiment, the valve core 32 is a hollow valve core 32, so that the weight of the valve core 32 can be reduced and the valve core 32 can be easily floated in the liquid.

[0042] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An adaptive plunger, comprising a plunger body (1), wherein a channel (11) is arranged in the plunger body (1), an exhaust hole (12) is arranged at the upper end of the plunger body (1), and a bypass hole (13) is arranged on the side wall of the bottom end of the plunger body (1), characterized in that: The channel (11) comprises a large diameter section (111) and a small diameter section (112), the exhaust hole (12) is connected to the small diameter section (112), and the bypass hole (13) is connected to the large diameter section (111); The adaptive plunger further comprises a valve seat (2) and a floating valve body (3); the valve seat (2) is arranged at the bottom end of the plunger body (1); a through hole (21) is arranged on the valve seat (2) so as to be connected with the large diameter section (111); the floating valve body (3) is arranged in the large diameter section (111) so as to move up and down. The floating valve body (3) has a floating state and a descending state that can be switched to each other. When in the floating state, the floating valve body (3) blocks the connection port between the small diameter section (112) and the large diameter section (111) and the through hole (21) to isolate the two. When in the descending state, the floating valve body (3) opens the connection port between the small diameter section (112) and the large diameter section (111) and the through hole (21) to connect the two.

2. The adaptive plunger according to claim 1, characterized in that: The valve seat (2) has a hollow cavity (22), the hollow cavity (22) is connected to the large diameter section (111), the through hole (21) is connected to the hollow cavity (22), and a portion of the floating valve body (3) slides in the hollow cavity (22) so as to be able to isolate the through hole (21) from the hollow cavity (22).

3. The adaptive plunger according to claim 2, characterized in that: A radial groove (23) is provided on the top of the valve seat (2), and the radial groove (23) extends from the side wall of the valve seat (2) to the hollow cavity groove (22); an opening at one end of the through hole (21) is provided in the radial groove (23), and the other end passes through the valve seat (2) downward.

4. The adaptive plunger according to claim 3, characterized in that: The plurality of radial grooves (23) are arranged at intervals along the circumferential direction of the hollow cavity groove (22).

5. The adaptive plunger according to claim 2, characterized in that: The floating valve body (3) comprises a float (31) and a valve core (32), wherein the float (31) is connected to the bottom of the valve core (32), the valve core (32) is movably disposed in the hollow cavity (22), and a through hole (34) penetrating from top to bottom is disposed on the float (31).

6. The adaptive plunger according to claim 5, characterized in that: One of the hollow cavity (22) and the floating body (31) is provided with a guide groove (4), and the other is provided with a guide key (5) that is slidably connected with the guide groove (4).

7. The adaptive plunger according to claim 5, characterized in that: The valve core (32) is divided into an upper body (321) and a lower body (322), the upper body (321) is cylindrical, and the lower body (322) is truncated cone-shaped, with the top surface of the truncated cone facing the float (31).

8. The adaptive plunger according to claim 5, characterized in that: The outer diameter of the valve core (32) is smaller than the inner diameter of the large diameter section (111).

9. The adaptive plunger according to claim 5, characterized in that: The floating valve body (3) further comprises a connecting rod (33), one end of which is connected to the valve core (32), and the other end of which is connected to the floating body (31), so that the valve core (32) and the floating body (31) are connected at an interval.

10. The adaptive plunger according to claim 5, characterized in that: The valve core (32) is a hollow body.

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