Anti-slip device for oil and gas well

Abstract

The utility model relates to an anti-slip device for an oil and gas well, which comprises a connecting pipe and an anti-slip mechanism arranged in the connecting pipe, oil and gas channels are arranged at the center of the connecting pipe and the center of the anti-slip mechanism, and a plurality of anti-slip flow channels are further arranged on the anti-slip mechanism. And the anti-slip flow channel is communicated with the oil gas channel through a plurality of liquid inlets and an annular liquid outlet. The device has no moving parts, is not easy to damage, does not occupy a central channel of a production pipe column, can prevent a liquid column from slipping without external force operation, greatly reduces the cost of oil and gas exploitation, and prolongs the service life of the production pipe column.

Description

Technical Field

[0001] The utility model belongs to the field of oil and natural gas mining equipment, and in particular relates to an anti-slip device for oil and gas wells. Background Art

[0002] Oil and gas wells are usually provided with casings in the wells, and a production string formed by connecting several oil and gas pipes end to end in sequence is provided in the casings. When in use, the fluid at the bottom of the oil and gas well is usually ejected upward to the ground along the production string under the action of pressure difference to realize oil and gas extraction. However, when the energy of the oil and gas well production layer decreases and the liquid carrying capacity of the gas decreases, under the action of the friction resistance of the production string, the natural gas flow rate decreases quickly near the inner wall of the production string, while the natural gas flow rate in the center of the production string decreases slowly, which makes the natural gas in the center of the pipe body flow upward, while the liquid near the pipe wall will slide down along the pipe wall, which is also called the liquid column slippage phenomenon (that is, the phenomenon that the oil and gas in the production string flows back downward along the pipe wall). When the liquid falls back to the bottom of the well and accumulates step by step, liquid accumulation will form, resulting in a further decrease in the pressure difference, and eventually causing the oil and gas well to be flooded.

[0003] In order to solve the above problems, the measures commonly used at present include: adding chemicals, installing gas lift valves, etc. Some even set a moving part check valve at the bottom of the production string to block the liquid from sliding down. These measures not only complicate the structure of the production string, but also require continuous maintenance during the oil and gas production process, such as adding chemicals and supplying gas, which increases the cost of oil and gas production. In addition, when a moving part check valve is set at the bottom of the production string, not only the central channel of the production string is blocked, resulting in the inability to send detection tools into the production string during production, thereby affecting the measurement of the liquid level parameters of the production layer, but also the moving parts are easily damaged, resulting in a reduced life of the production string.

[0004] Therefore, it is very important to develop an anti-slip device for oil and gas wells that does not occupy the central channel of the production string and can prevent the slip of the liquid column without external force operation. Utility Model Content

[0005] The purpose of the utility model is to overcome the defects in the prior art and provide an anti-slip device for oil and gas wells, which has no moving parts, is not easy to be damaged, does not occupy the central channel of the production pipe string, can prevent the liquid column from slipping without relying on external force operation, greatly reduces the cost of oil and gas production, and increases the service life of the production pipe string.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0007] An anti-slip device for oil and gas wells comprises a connecting pipe and an anti-slip mechanism arranged in the connecting pipe. Oil and gas channels are arranged at the center of the connecting pipe and the center of the anti-slip mechanism. The anti-slip mechanism is also provided with a plurality of anti-slip flow channels, and the anti-slip flow channels are connected to the oil and gas channels through a plurality of liquid inlets and an annular liquid outlet.

[0008] As a further technical solution, the anti-slip flow channel includes an annular cavity, a U-shaped flow channel arranged below the annular cavity and having a U-shaped cross-section, several liquid inlets connecting the annular cavity and the oil and gas channel, and an annular liquid outlet arranged on the U-shaped flow channel near one end of the oil and gas channel.

[0009] As a further technical solution, the U-shaped flow channel is arranged obliquely, and the distance from the end of the U-shaped flow channel to the central axis of the connecting pipe is smaller than the distance from the middle part to the central axis of the connecting pipe.

[0010] As a further technical solution, the anti-slip mechanism comprises a bottom end pad, a plurality of anti-slip middle tubes and an anti-slip top tube which are spliced ​​end to end from bottom to top;

[0011] As a further technical solution, the bottom end pad includes a first outer tube body;

[0012] As a further technical solution, the anti-slip intermediate tube and the anti-slip top tube both include a second outer tube body, an annular groove formed on the inner wall of the second outer tube body, and an inner tube body disposed in the annular groove and threadedly connected to the annular groove;

[0013] As a further technical solution, grooves are provided on the top walls of the first outer tube body and the anti-slip intermediate tube;

[0014] As a further technical solution, a gap is provided between the inner tube body and the annular groove wall, thereby forming a connected annular cavity and an upper half flow channel;

[0015] The bottom of the inner tube body is arranged in the groove, and a gap is arranged between the inner tube body and the groove wall, thereby forming a lower half flow channel;

[0016] The upper half flow channel and the lower half flow channel are connected to form the U-shaped flow channel as a whole.

[0017] As a further technical solution, the inner tube body includes an annular tube body and an annular baffle arranged at the bottom of the annular tube body and inclined; the distance from the upper part of the annular baffle to the central axis of the inner tube body is smaller than the distance from the lower part to the central axis of the inner tube body.

[0018] As a further technical solution, a plurality of the liquid inlets are evenly arranged along the circumference at the lower part of the annular tube body.

[0019] As a further technical solution, the connecting pipe includes an outer shell and an upper joint arranged on the top of the outer shell and connected to the outer shell by threads;

[0020] As a further technical solution, a limiting boss is arranged in the outer shell, and the anti-slip mechanism is arranged in the outer shell through the limiting boss and the upper joint.

[0021] As a further technical solution, one end of the connecting pipe is provided with an external thread, and the other end is provided with an internal thread.

[0022] As a further technical solution, a gasket is sandwiched between the anti-slip mechanism and the upper joint;

[0023] As a further technical solution, the gasket includes a stainless steel gasket and a nitrile rubber gasket arranged on one side of the stainless steel gasket.

[0024] As a further technical solution, a sealant is further provided between the gap between the outer shell and the upper joint.

[0025] Compared with the prior art, the beneficial effects of the utility model are:

[0026] 1. Based on the traditional Tesla valve, the utility model improves the planar structure into a three-dimensional tubular structure, and sets the anti-slip flow channel on the side wall of the tube body, leaving the central channel of the production string, and preparing an anti-slip device, which can be applied to the pipeline to realize the full-diameter (without constriction) setting of the entire production string, thereby avoiding a series of problems caused by the traditional one-way valve occupying the central channel, and it has no moving parts, is not easy to be damaged, and extends the service life of the production string.

[0027] 2. The anti-slip device of the utility model utilizes the principle of the Tesla valve and the difference in flow resistance of oil and gas in different flow directions to achieve one-way flow of oil and gas, thereby preventing the liquid column from slipping. When the oil and gas well begins production, the oil and gas move upward along the production string equipped with the anti-slip device, and when the liquid column near the inner wall of the production string slips downward, the liquid is diverted in the process of flowing down along the inner tube body, and part of the liquid enters the anti-slip flow channel through the liquid inlet and flows out from the liquid outlet. At this time, this part of the liquid flow has turned back upward, thereby colliding with the liquid flowing downward, hindering the liquid from flowing downward, and achieving the anti-slip of the liquid column.

[0028] In summary, the utility model can increase the drainage capacity of the oil and gas well by utilizing the principle of the Tesla valve without occupying the central channel of the production tubing and without relying on external force operation, thereby preventing the liquid column from slipping and achieving the purpose of avoiding liquid accumulation. Compared with traditional technologies, it does not use moving parts and is not easy to be damaged, thus extending the service life of the production tubing, and does not require external force operation, thereby reducing the cost of oil and gas extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of an anti-slip device for oil and gas wells in one embodiment of the utility model;

[0030] Figure 2 This is a schematic structural diagram of an anti-slip top tube in one embodiment of the utility model;

[0031] Figure 3 This is a schematic structural diagram of an anti-slip intermediate tube in one embodiment of the utility model;

[0032] Figure 4 This is a schematic diagram of the structure of the bottom end pad in one embodiment of the utility model;

[0033] Figure 5 This is a working principle diagram of an anti-slip device for oil and gas wells when the production capacity is high in one embodiment of the utility model;

[0034] Figure 6 This is a working principle diagram of an anti-slip device for oil and gas wells when production capacity is low in one embodiment of the utility model;

[0035] Figure 7 This is a schematic diagram of the structure of a liquid-free production column in one embodiment of the utility model;

[0036] Figure 8 This is a structural schematic diagram of a production and drainage system for oil and gas wells in one embodiment of the utility model;

[0037] In the figure: 1, connecting pipe, 2, anti-slip mechanism, 3, oil and gas channel, 4, liquid inlet, 5, annular liquid outlet, 6, anti-slip flow channel, 7, bottom end pad, 8, anti-slip intermediate pipe, 9, anti-slip top pipe, 10, first outer tube body, 11, second outer tube body, 12, inner tube body, 13, groove, 14, annular cavity, 15, upper half flow channel, 16, lower half flow channel, 17, annular tube body, 18, annular partition, 19, gasket accommodating groove, 20, annular cavity, 21, U-shaped flow channel, 22, outer shell, 23, upper joint, 24, limiting boss, 25, external thread, 26, internal thread, 27, gasket, 28, liquid accumulation-free production string, 29, oil pipe, 30, anti-slip device for oil and gas wells, 31, casing, 32, guide shoe, 33, artificial bottom of well. DETAILED DESCRIPTION

[0038] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0039] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present utility model, the term "liquid accumulation free" is explained as follows: slippage refers to the phenomenon that in a gas-liquid two-phase pipe flow, gas exceeds the flow of liquid due to the density difference between gas and liquid, that is, the gas in the center of the production tubing rises, while the liquid slides downward in the part close to the inner wall of the production tubing; due to the existence of the slippage phenomenon, the gas phase in the wellbore of the oil and gas well is insufficient to carry the liquid phase, resulting in the liquid phase falling back to the bottom of the well, accumulating step by step to form liquid accumulation; liquid accumulation free means hindering the formation of liquid accumulation and preventing the production of oil and gas wells from being affected by the liquid accumulation in the production tubing, which is called liquid accumulation free.

[0042] The present invention will be described in further detail below with reference to the accompanying drawings.

[0043] Example 1

[0044] like Figure 1-4The utility model shown is an embodiment of an anti-slip device for oil and gas wells, comprising a connecting pipe 1, an anti-slip mechanism 2 arranged in the connecting pipe 1, an oil and gas channel 3 is arranged at the center of the connecting pipe 1 and the center of the anti-slip mechanism 2, and a plurality of anti-slip flow channels 6 are also arranged on the anti-slip mechanism 2, and the anti-slip flow channels 6 are connected with the oil and gas channel 3 through a plurality of liquid inlets 4 and an annular liquid outlet 5. On the basis of the traditional Tesla valve, the utility model improves the planar structure into a three-dimensional tubular structure, and arranges the anti-slip flow channel on the side wall of the pipe body, leaving the central channel of the production string, and prepares an anti-slip device, which can be applied to the pipeline to realize the full-diameter (without constriction) setting of the entire production string, thereby avoiding a series of problems caused by the traditional one-way valve occupying the central channel, and it has no moving parts, is not easy to be damaged, and prolongs the service life of the production string.

[0045] As an embodiment of an anti-slip device for oil and gas wells of the utility model, the anti-slip flow channel 6 includes an annular cavity 20, a U-shaped flow channel 21 with a U-shaped cross-section arranged below the annular cavity 20, a plurality of liquid inlets 4 connecting the annular cavity 20 and the oil and gas channel 3, and an annular liquid outlet 5 arranged on the U-shaped flow channel 21 near one end of the oil and gas channel 3.

[0046] As an embodiment of the utility model of an anti-slip device for oil and gas wells, the U-shaped flow channel 21 is inclined, and the distance from the end of the U-shaped flow channel 21 to the central axis of the connecting pipe 1 is smaller than the distance from the middle to the central axis of the connecting pipe 1. The anti-slip device of the utility model utilizes the principle of the Tesla valve and the difference in flow resistance of oil and gas flow in different flow directions to achieve one-way flow of oil and gas, thereby achieving the purpose of preventing the liquid column from slipping. When the oil and gas well starts production, the oil and gas move upward along the production tubing equipped with the anti-slip device, and when the liquid column near the inner wall of the production tubing slips downward, the liquid is diverted in the process of flowing down along the inner tube body, and part of the liquid enters the anti-slip flow channel through the liquid inlet and flows out from the liquid outlet. At this time, the part of the liquid flow has turned back upward, thereby colliding with the liquid flowing downward, hindering the liquid from flowing downward, and achieving the anti-slip of the liquid column.

[0047] As an embodiment of the anti-slip device for oil and gas wells of the utility model, the anti-slip mechanism 2 includes a bottom end pad 7, a plurality of anti-slip intermediate pipes 8 and an anti-slip top pipe 9 which are spliced ​​end to end from bottom to top;

[0048] As an embodiment of the anti-slip device for oil and gas wells of the utility model, the bottom end pad 7 includes a first outer tube body 10;

[0049] As an embodiment of the anti-slip device for oil and gas wells of the utility model, the anti-slip intermediate pipe 8 and the anti-slip top pipe 9 both include a second outer pipe body 11, an annular groove provided on the inner wall of the second outer pipe body 11, and an inner pipe body 12 disposed in the annular groove and threadedly connected to the annular groove;

[0050] As an embodiment of the anti-slip device for oil and gas wells of the utility model, a groove 13 is provided on the top wall of the first outer tube body 10 and the anti-slip intermediate tube;

[0051] A gap is provided between the inner tube body 12 and the annular groove wall, thereby forming a connected annular cavity 20 and an upper half flow channel 15;

[0052] The bottom of the inner tube body 12 is disposed in the groove 13, and a gap is provided between the inner tube body 12 and the groove wall of the groove 13, thereby forming a lower half flow channel 16;

[0053] The upper half flow channel 15 and the lower half flow channel 16 are connected to each other, and constitute the U-shaped flow channel 21 as a whole.

[0054] As an embodiment of an anti-slip device for oil and gas wells of the utility model, the inner tube body 12 includes an annular tube body 17, and an annular baffle 18 which is arranged at the bottom of the annular tube body 17 and is inclined; the distance from the upper part of the annular baffle 18 to the central axis of the inner tube body 12 is smaller than the distance from the lower part to the central axis of the inner tube body 12.

[0055] As an embodiment of the anti-slip device for oil and gas wells of the utility model, a plurality of liquid inlets 4 are evenly arranged at the lower part of the annular tube body 17 along the circumference.

[0056] As an embodiment of the anti-slip device for oil and gas wells of the utility model, the connecting pipe 1 includes an outer shell 22 and an upper joint 23 disposed on the top of the outer shell 22 and connected to the outer shell 22 by threads;

[0057] As an embodiment of the anti-slip device for oil and gas wells of the utility model, a limiting boss 24 is provided in the outer shell 22 , and the anti-slip mechanism 2 is provided in the outer shell 22 through the limiting boss 24 and the upper joint 23 .

[0058] As an embodiment of the anti-slip device for oil and gas wells of the utility model, one end of the connecting pipe 1 is provided with an external thread 25, and the other end is provided with an internal thread 26.

[0059] As an embodiment of the anti-slip device for oil and gas wells of the utility model, a gasket 27 is sandwiched between the anti-slip mechanism 2 and the upper joint 23 .

[0060] As an embodiment of the anti-slip device for oil and gas wells of the utility model, the gasket 27 comprises a stainless steel gasket and a nitrile rubber gasket arranged on one side of the stainless steel gasket, which can seal the gap between the anti-slip mechanism 2 and the upper joint 23 .

[0061] As an embodiment of the anti-slip device for oil and gas wells of the utility model, an annular receiving groove is arranged on the top wall of the anti-slip top pipe, and the gasket 27 is arranged in the annular receiving groove.

[0062] As an embodiment of the anti-slip device for oil and gas wells of the utility model, a sealant is further provided between the gap between the outer shell 22 and the upper joint 23 .

[0063] Example 2

[0064] like Figure 7 An embodiment of a production string of the utility model shown in the figure comprises a plurality of oil pipes 29 connected end to end in sequence and a plurality of anti-slip devices 30 for oil and gas wells as described in Example 1, wherein a plurality of oil pipes 29 are spaced between adjacent anti-slip devices 30 for oil and gas wells.

[0065] As an embodiment of a production string of the utility model, the oil and gas well anti-slip device 30 is connected to the adjacent oil pipe 29 through threads.

[0066] Example 3

[0067] like Figure 8 An embodiment of an oil and gas well production and drainage system of the utility model is shown, comprising a casing 31 and a production string 28 as described in Example 2 arranged in the casing 31 , and an annular cavity 14 is arranged between the casing 31 and the production string 28 .

[0068] In one embodiment of the oil and gas well production and drainage system of the utility model, a guide shoe 32 is provided at the bottom of the production pipe string 28;

[0069] In an embodiment of an oil and gas well production and drainage system of the utility model, an artificial well bottom 33 is arranged at the bottom of the casing 31 .

[0070] The working principle of this utility model:

[0071] When the energy of the production layer is large, such as Figure 5 As shown, under the action of the pressure difference, the gas carries the liquid (oil-gas mixture) and moves upward along the oil-gas channel 3 of the production string and sprays out of the ground to collect oil and gas;

[0072] When the energy of the production layer decreases and the pressure difference becomes smaller, the gas's liquid carrying capacity decreases, and the transmission of the friction force of the production string is viscous, such as Figure 6As shown, this causes the gas to move upward along the center of the production tubing, while the liquid slides downward along the inner wall of the production tubing, that is, the liquid column slips. At this time, in the process of the liquid sliding downward along the inner wall of the production tubing, when it slides to the anti-slip flow channel 6, liquid diversion is achieved, part of the liquid continues to slide, and the other part of the liquid enters the anti-slip flow channel 6, returns and moves upward through the liquid inlet 4, the annular cavity 20 and the U-shaped flow channel 21, and flows out from the annular liquid outlet 5. The liquid flowing out of the anti-slip flow channel 6 collides with the other part of the liquid sliding down along the inner wall, thereby blocking the further sliding of the liquid, and realizing the function of preventing the liquid column from slipping. It uses the principle of the Tesla valve and the difference in flow resistance of oil and gas flow in different flow directions to achieve unidirectional circulation of oil and gas. Compared with traditional technologies, the liquid column anti-slip process does not require additional external force operation and maintenance, greatly reducing the cost of oil and gas collection. In addition, the utility model does not occupy the central channel of the production tubing, does not use moving parts, is not easy to be damaged, and extends the service life of the production tubing.

[0073] Application Cases

[0074] Since the contents of each operation section before and after the construction are different, the time used is quite different, and it is impossible to compare and analyze the changes in drainage one by one. Therefore, the utility model uses nitrogen truck gas lift to start the well in the gas lift and drainage stage of the natural gas self-flowing well, and compares the production and drainage effects of the traditional production string and the production string of the utility model. The results are as follows:

[0075] 1. Before running the utility model liquid-free production string, a total of 6 gas lifts were performed:

[0076] The first gas lift after fracturing of the well: fluid production started at 17.2MPa, and the highest casing pressure was 19.5MPa;

[0077] The second to fifth gas lifts: no production due to pipeline blockage;

[0078] The sixth gas lift: The gas lift lasted 24 hours, and the liquid production started at 8.7 MPa, with the highest pressure at 18.1 MPa.

[0079] 2. After the utility model liquid accumulation-free production string was lowered, two gas lifts were performed:

[0080] The seventh gas lift: The gas lift time was 10 hours. When the gas lift casing pressure reached 6.5 MPa, a small amount of liquid began to be discharged. When it reached 9.3 MPa, a large amount of liquid began to be discharged. The highest pressure was 14.3 MPa.

[0081] The eighth gas lift: Before the gas lift, the well was being opened for blowout and fluid discharge. The gas lift was started when the casing pressure was 7.6 MPa. The fluid discharge state was maintained before and after the gas lift. The gas lift lasted for 6 hours. The highest pressure was 11.96 MPa. After the gas lift was stopped, when the casing pressure dropped to 5.1 MPa, fluid could still be discharged intermittently.

[0082] It can be seen from the above data that after using the production string composed of the anti-slip device and the oil pipe of the utility model, the start-up liquid pressure is reduced from 8.7 MPa to 6.5 MPa, and the lifting pressure is reduced from 19.5 MPa to 14.32 MPa. When the casing pressure is only 5.1 MPa, intermittent liquid production can still be achieved and continuous gas production can be maintained. It can be seen that after the production string of the utility model is installed, the pressure required for well start-up liquid discharge is lower, the lifting time during gas lift is shorter, and a higher liquid carrying capacity can be achieved with a lower pressure.

[0083] The above-mentioned embodiments are only preferred embodiments of the present invention, and are not exhaustive of the feasible implementations of the present invention. For those skilled in the art, any obvious changes made to the present invention without departing from the principle and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. An anti-slip device for oil and gas wells, characterized in that: The invention comprises a connecting pipe (1), an anti-slip mechanism (2) arranged in the connecting pipe (1), an oil and gas channel (3) being arranged at the center of the connecting pipe (1) and the center of the anti-slip mechanism (2), and a plurality of anti-slip flow channels (6) being arranged on the anti-slip mechanism (2), and the anti-slip flow channels (6) being connected to the oil and gas channel (3) via a plurality of liquid inlets (4) and an annular liquid outlet (5).

2. The anti-slip device for oil and gas wells according to claim 1, characterized in that: The anti-slip flow channel (6) comprises an annular cavity (20), a U-shaped flow channel (21) disposed below the annular cavity (20) and having a U-shaped cross section, a plurality of liquid inlets (4) connecting the annular cavity (20) and the oil and gas channel (3), and an annular liquid outlet (5) disposed at one end of the U-shaped flow channel (21) close to the oil and gas channel (3).

3. The anti-slip device for oil and gas wells according to claim 2, characterized in that: The U-shaped flow channel (21) is arranged obliquely, and the distance from the end of the U-shaped flow channel (21) to the central axis of the connecting pipe (1) is smaller than the distance from the middle to the central axis of the connecting pipe (1).

4. The anti-slip device for oil and gas wells according to claim 2, characterized in that: The anti-slip mechanism (2) comprises a bottom end pad (7), a plurality of anti-slip middle tubes (8) and an anti-slip top tube (9) which are spliced ​​end to end from bottom to top; The bottom end pad (7) comprises a first outer tube body (10); The anti-slip intermediate tube (8) and the anti-slip top tube (9) both comprise a second outer tube body (11), an annular groove formed on the inner wall of the second outer tube body (11), and an inner tube body (12) disposed in the annular groove and threadedly connected to the annular groove; Grooves (13) are provided on the top walls of the first outer tube body (10) and the anti-slip intermediate tube; A gap is provided between the inner tube body (12) and the annular groove wall, thereby forming a connected annular cavity (20) and an upper half flow channel (15); The bottom of the inner tube body (12) is arranged in the groove (13), and a gap is provided between the inner tube body (12) and the groove wall of the groove (13), thereby forming a lower half flow channel (16); The upper half flow channel (15) and the lower half flow channel (16) are connected to each other and constitute the U-shaped flow channel (21) as a whole.

5. The anti-slip device for oil and gas wells according to claim 4, characterized in that: The inner tube body (12) comprises an annular tube body (17), and an annular partition plate (18) arranged at the bottom of the annular tube body (17) and arranged obliquely; The plurality of liquid inlets (4) are evenly arranged along the circumference at the lower portion of the annular tube body (17).

6. The anti-slip device for oil and gas wells according to claim 1, characterized in that: The connecting pipe (1) comprises an outer shell (22) and an upper joint (23) arranged on the top of the outer shell (22) and connected to the outer shell (22) by means of threads; A limiting boss (24) is provided in the outer shell (22), and the anti-slip mechanism (2) is arranged in the outer shell (22) via the limiting boss (24) and the upper joint (23).

7. The anti-slip device for oil and gas wells according to claim 6, characterized in that: A gasket (27) is sandwiched between the anti-slip mechanism (2) and the upper joint (23).

8. The anti-slip device for oil and gas wells according to claim 6, characterized in that: A sealant is also provided between the gap between the outer shell (22) and the upper joint (23).

9. The anti-slip device for oil and gas wells according to claim 1, characterized in that: One end of the connecting pipe (1) is provided with an external thread (25), and the other end is provided with an internal thread (26).

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