阅读说明：本技术 一种基于含水溶部件的气井控水结构 (Gas well water control structure based on water-containing solution part ) 是由 裴柏林 吴建昌 周祥 宋晓强 于 2021-08-19 设计创作，主要内容包括：一种基于含水溶部件的气井控水结构,包括设置在基管上的采气通道,还包括设置在采气通道中的水溶限位结构和堵塞体；其中,所述水溶限位结构未遇水时,所述堵塞体在水溶限位结构的支撑下位于初始位置,保持采气通道畅通；所述水溶限位结构遇水后溶解,释放所述堵塞体；所述堵塞体移动至堵塞位置,阻塞采气通道。本发明一种基于含水溶部件的气井控水结构,通过设置水溶限位结构,当采气通道进水后,所述水溶限位结构遇水溶解释放堵塞体,所述堵塞体在力的作用下运动并堵塞采气通道流道,从而控制相关井段的地层水进入基管内部。本发明可以可有效解决生产过程中一段或多段地层出水,导致井内有积水积液,使气井开采产量下降及气井寿命降低的问题。(A gas well water control structure based on a water-soluble component comprises a gas production channel arranged on a base pipe, and further comprises a water-soluble limiting structure and a blocking body which are arranged in the gas production channel; when the water-soluble limiting structure does not meet water, the blocking body is positioned at an initial position under the support of the water-soluble limiting structure, so that the gas production channel is kept smooth; the water-soluble limiting structure is dissolved after meeting water, and the plugging body is released; the blocking body moves to a blocking position to block the gas production channel. According to the gas well water control structure based on the water-soluble component, the water-soluble limiting structure is arranged, when the gas production channel is filled with water, the water-soluble limiting structure is dissolved in the water to release the blocking body, the blocking body moves under the action of force and blocks a gas production channel flow passage, and therefore formation water of a related well section is controlled to enter the base pipe. The invention can effectively solve the problems that the production yield of the gas well is reduced and the service life of the gas well is shortened due to accumulated water and accumulated liquid in the well caused by water outflow from one or more sections of stratums in the production process.)

1. The utility model provides a gas well water control structure based on contain water and dissolve part, is including setting up the gas production passageway on the parent tube which characterized in that: the gas production device also comprises a water-soluble limiting structure and a plugging body which are arranged in the gas production channel; wherein the content of the first and second substances,

when the water-soluble limiting structure does not meet water, the blocking body is positioned at an initial position under the support of the water-soluble limiting structure, so that the gas production channel is kept smooth;

the water-soluble limiting structure is dissolved after meeting water, and the plugging body is released; the blocking body moves to a blocking position to block the gas production channel.

2. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: the time length of dissolving the water-soluble limiting structure after meeting water is 3-1000 hours.

3. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: and a drainage channel for draining water is arranged below the gas production channel.

4. A gas well water control structure based on water-containing components as claimed in claim 3, characterized in that: the drainage channel is provided with a flow control device.

5. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: the diameter of the blocking body is larger than that of the gas production channel at the rear end of the throat pipe and smaller than that of the gas production channel at the front end of the throat pipe.

6. A water control structure for a gas well based on water-containing components as claimed in claim 5, wherein: the water-soluble limiting structure is arranged at the throat and is of a cylindrical structure, one end of the water-soluble limiting structure is supported at the rear end of the throat, and the other end of the water-soluble limiting structure is supported on the plugging body at the front end of the throat; the side wall of the blocking body is provided with a hollow part or a through hole for allowing gas to pass through.

7. A water control structure for a gas well based on water-containing components as claimed in claim 5, wherein: the water-soluble limiting structure is a flat structure with sieve pores or through holes, the diameter of the water-soluble limiting structure is consistent with that of the gas production channel at the front end of the throat pipe, and the water-soluble limiting structure is arranged in the gas production channel at the front end of the throat pipe and is matched with the baffle for use, so that the plugging body is positioned.

8. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: the gas production channel is provided with a right-angle bend, and the front end of the bend is sequentially provided with a plug, a spring, a plugging body and a water-soluble limiting structure; wherein the content of the first and second substances,

the plug is arranged at one end or one side of the water control ring, and the inner side of the plug is propped against a pre-extruded spring; the other end of the spring props against the blocking body, and the other end of the blocking body is limited in the water control ring and is positioned at a right-angle corner of the gas production channel;

after the water-soluble limiting structure is dissolved in water, the blocking body moves to the right-angle bent part of the gas production channel under the action of the spring; the side surface of the blocking body seals the gas production channel at the right-angle bent part.

9. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: the gas production channel is provided with a right-angle bend, and the front end of the bend is sequentially provided with a plug, a flow guide body, a water-soluble limiting structure, a blocking body and a spring; wherein the content of the first and second substances,

the spring is in a compressed state; the flow guide body is of a cylindrical structure and is arranged at the right-angle bent part of the gas production channel; one end of the blocking body facing to the flow guide body is conical;

after the water-soluble limiting structure is dissolved in water, the blocking body moves towards the flow guide body under the action of the spring; the cone of the blocking body is matched with the cavity of the flow guide body to seal the gas production channel.

10. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: the front part of the gas production channel is provided with a water-soluble limiting structure, and the water-soluble limiting structure is a cavity structure with a water-soluble particle bin in the middle; the plugging body is fine particles arranged in the water soluble particle bin, the density of the plugging body is less than that of formation water, and the diameter of the plugging body is 0.1-5 mm; the rear portion of gas production passageway is equipped with the granule and intercepts the subassembly, the granule is held back the subassembly and is the screen cloth structure, and the mesh diameter is less than the diameter of jam body.

11. A water control structure for a gas well based on water-containing components as claimed in claim 1 wherein: a bell mouth-shaped throat pipe is arranged in the gas production channel; the water-soluble limiting structure is a water-soluble stay wire structure; the blocking body is a spherical structure with the density smaller than that of water, and the diameter of the blocking body is larger than the diameter of the rear end of the throat pipe and smaller than the diameter of the front end of the throat pipe; one end of the water soluble stay wire is arranged at the bottom of the filter sleeve, and the other end of the water soluble stay wire is connected with the plugging body.

12. A base pipe, characterized by: the base pipe comprises a water control structure for a water-containing component-based gas well according to any one of claims 1 to 11.

13. A gas well completion structure comprising a wellbore and a base pipe located in the wellbore, wherein: the base pipe comprises a water control structure for a water-containing component-based gas well according to any one of claims 1 to 11.

Technical Field

The invention belongs to the technical field of gas well exploitation, relates to a gas well water control structure, and particularly relates to a gas well water control structure based on a water-containing solution component.

Background

In the technical field of oil and gas well exploitation, the stratum conditions of oil and gas fields are usually complex, and the permeability and seepage speed between the layers of a multilayer oil and gas field are different, so that some stratums produce water in advance.

To the oil well problem of producing water, can adopt the accuse to flow the screen pipe and realize accuse water, for example chinese utility model patent 200920166948.9 discloses a seam filter sleeve accuse that the inboard is equipped with fixed stay flows the screen pipe, is provided with a accuse on the screen pipe and flows the device, the entry that the accuse flowed the device meets with the water conservancy diversion layer, and the export that the accuse flowed the device meets with basic pipe entry. When the filter sleeve is used, two ends of the filter sleeve are isolated from the outside through the end ring of the sieve tube, and fluid can only enter the flow guide layer through the filter sleeve. Because the flow guide layer meets the inlet of the flow control device, and the outlet of the flow control device meets the inlet of the base pipe, in the oil production process, the fluid flows through the filter sleeve, the flow guide layer, the inlet of the flow control device, the outlet of the flow control device and the inlet of the base pipe in sequence to enter the base pipe. The flow control sieve tube plays a role in controlling large change of flow to a certain extent, and the purpose of flow control is achieved.

However, the flow control screen disclosed in the above patent is only applicable to water control in oil wells and is not applicable to water control in gas wells. For gas well water production problems (where "water" generally refers to fluids such as water, oil, and oil-water mixtures produced from the formation), the produced fluids accumulate in the wellbore due to the weak ability of the produced gas carrying fluid to form wellbore fluid. Wellbore fluid accumulation can cause two problems: firstly, the water lock effect causes the gas production capability of the liquid accumulation well section to be seriously reduced and even to be invalid; secondly, along with the continuous production, the liquid level of the shaft effusion rises continuously, so that the back pressure of the stratum outlet is increased, the gas yield is further reduced, and the gas well can be stopped.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a water control structure of a gas well based on a water-soluble component, which can automatically close a gas production channel in a stratum and a pipe column in time and realize an automatic water control function aiming at the problem of water outflow of one or more stratums in the gas well exploitation process.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a gas well water control structure based on contain water and dissolve part, is including setting up the gas production passageway on the parent tube which characterized in that: the gas production device also comprises a water-soluble limiting structure and a plugging body which are arranged in the gas production channel; when the water-soluble limiting structure does not meet water, the blocking body is positioned at an initial position under the support of the water-soluble limiting structure, so that the gas production channel is kept smooth; the water-soluble limiting structure is dissolved after meeting water, and the plugging body is released; the blocking body moves to a blocking position to block the gas production channel.

Further, the time length of dissolving the water-soluble limiting structure after meeting water is 3-1000 hours.

Further, a drainage channel for draining water is arranged below the gas production channel.

Further, the drainage channel is provided with a flow control device.

Furthermore, a bell mouth-shaped throat pipe is arranged in the gas production channel, a spherical blocking body is arranged at the front end of the throat pipe, and the diameter of the blocking body is larger than that of the gas production channel at the rear end of the throat pipe and smaller than that of the gas production channel at the front end of the throat pipe.

Furthermore, a water-soluble limiting structure is arranged at the throat, the water-soluble limiting structure is of a cylindrical structure, one end of the water-soluble limiting structure is supported at the rear end of the throat, and the other end of the water-soluble limiting structure is supported on the plugging body at the front end of the throat; the side wall of the blocking body is provided with a hollow part or a through hole for allowing gas to pass through.

Furthermore, the water-soluble limiting structure is a flat-plate-shaped structure with sieve pores or through holes, the diameter of the water-soluble limiting structure is consistent with that of the gas production channel at the front end of the throat pipe, and the water-soluble limiting structure is arranged in the gas production channel at the front end of the throat pipe and is matched with the baffle plate for use, so that the plugging body is positioned.

Further, the gas production channel is provided with a right-angle bend, and the front end of the bend is sequentially provided with a plug, a spring, a plugging body and a water-soluble limiting structure; wherein the plug is arranged at one end or one side of the water control ring, and the inner side of the plug is propped against a pre-extruded spring; the other end of the spring props against the blocking body, and the other end of the blocking body is limited in the water control ring and is positioned at a right-angle corner of the gas production channel; after the water-soluble limit structure is dissolved in water, the plugging body moves towards the right-angle bending part of the gas production channel under the action of the spring and depends on the side surface of the plugging body to seal the gas production channel at the right-angle bending part.

Further, the gas production channel is provided with a right-angle bend, and the front end of the bend is sequentially provided with a plug, a flow guide body, a water-soluble limiting structure, a blocking body and a spring; wherein the spring is in a compressed state; the flow guide body is of a cylindrical structure and is arranged at the right-angle bent part of the gas production channel; one end of the blocking body facing to the flow guide body is conical; after the water-soluble limiting structure is dissolved in water, the blocking body moves towards the direction of the flow guide body under the action of the spring, and the pyramid part of the blocking body is matched with the cavity of the flow guide body, so that the gas production channel is closed.

Furthermore, a water-soluble limiting structure is arranged at the front part of the gas production channel, and the water-soluble limiting structure is a cavity structure with a water-soluble particle bin in the middle; the plugging body is fine particles arranged in the water soluble particle bin, the density of the plugging body is less than that of formation water, and the diameter of the plugging body is 0.1-5 mm; the rear portion of gas production passageway is equipped with the granule and intercepts the subassembly, the granule is held back the subassembly and is the screen cloth structure, and the mesh diameter is less than the diameter of jam body.

Furthermore, a bell mouth-shaped throat pipe is arranged in the gas production channel; the water-soluble limiting structure is a water-soluble stay wire structure; the blocking body is a spherical structure with the density smaller than that of water, and the diameter of the blocking body is larger than the diameter of the rear end of the throat pipe and smaller than the diameter of the front end of the throat pipe; one end of the water soluble stay wire is arranged at the bottom of the filter sleeve, and the other end of the water soluble stay wire is connected with the plugging body.

In order to achieve the purpose, the invention adopts the following technical scheme:

a base pipe comprising a gas well water control structure based on a water-containing component as described above.

In order to achieve the purpose, the invention adopts the following technical scheme:

a gas well completion structure comprising a wellbore and a base pipe located in the wellbore, the base pipe comprising a water-soluble component-based gas well water control structure as described above.

According to the gas well water control structure based on the water-soluble component, the water-soluble limiting structure is arranged, after water enters the gas production channel, the water-soluble limiting structure is dissolved in the water to release the blocking body, the blocking body moves under the action of force and automatically blocks the gas production channel flow passage, so that formation water of a related well section is controlled to enter the interior of the base pipe, and automatic water control is realized. The invention can effectively solve the problems that the production yield of the gas well is reduced and the service life of the gas well is shortened due to accumulated water and accumulated liquid in the well caused by water outflow from one or more sections of stratums in the production process.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a water control structure of a gas well based on a water-containing structure in example 1 of the present invention;

FIG. 2 is a top view of FIG. 1;

FIG. 3 is an enlarged partial schematic view at A in FIG. 2;

FIG. 4 is an enlarged, fragmentary schematic view of the portion of the water control screen of FIG. 1;

fig. 5 is a partially enlarged schematic view of a flow path portion in fig. 4.

FIG. 6 is a schematic illustration of the change in position of the occluding body of FIG. 4 partially within a water control screen in the presence of water;

fig. 7 is a schematic structural diagram (including a drainage structure) of the whole gas well water control structure based on a water-containing structure in example 2 of the invention;

FIG. 8 is a schematic diagram of the overall structure of another water control structure of a gas well based on a water-containing structure (including another drainage structure) in example 2 of the invention;

FIG. 9 is a schematic diagram of the overall structure of a water control structure of a gas well based on a water-containing structure in example 3;

FIG. 10 is an enlarged, fragmentary schematic view of the portion of the water control screen of FIG. 9;

FIG. 11 is a schematic illustration of the schematic illustration of FIG. 10 after the position of the occluding body has been changed after the portion of the occluding body has been exposed to water within the water control screen;

FIG. 12 is a schematic diagram showing the overall structure of a water control structure of a gas well based on a water-containing structure in example 4;

FIG. 13 is an enlarged, fragmentary schematic view of the portion of the water control screen of FIG. 12;

FIG. 14 is a schematic illustration of the schematic illustration of FIG. 13 after the position of the occluding body has been changed after the water is encountered partially within the water control screen;

FIG. 15 is a schematic diagram showing the overall structure of a water control structure of a gas well based on a water-containing structure in example 5;

FIG. 16 is an enlarged, fragmentary schematic view of the portion of the water control screen of FIG. 15;

FIG. 17 is a schematic illustration of the plugging body of FIG. 16 before and after a change in position after encountering water within the water control screen;

FIG. 18 is a schematic diagram showing the overall structure of a water control structure of a gas well based on a water-containing structure in example 6;

FIG. 19 is a schematic illustration of the portion of the water control screen section of FIG. 18 after the plugging body has been repositioned when exposed to water within the water control screen;

FIG. 20 is a schematic diagram showing the overall structure of a water control structure of a gas well based on a water-containing structure in example 7;

FIG. 21 is a schematic illustration of the position of the occluding body of FIG. 20 after a portion of the water control screen section has been exposed to water within the water control screen.

Detailed Description

The following further describes a concrete embodiment of the gas well water control structure based on the water-containing solution component in combination with the attached drawings 1-21. It should be noted that the drawings in the specification are only for the purpose of more intuitively illustrating the whole or part of the specific features of the technical solution disclosed in the embodiment, and the proportion or the dimensional structure thereof is not drawn according to the actual product, and therefore, the technical solution disclosed in the embodiment cannot be specifically limited. The gas well water control structure based on the water-containing structure of the present invention is also not limited to the description of the following examples.

The invention provides a plurality of gas well water control structures based on water-soluble components in the following embodiments 1-6, which comprise a gas production channel arranged on a base pipe, and also comprise a water-soluble limiting structure and a plugging body arranged in the gas production channel; when the water-soluble limiting structure is in an initial state, the water-soluble limiting structure does not meet water, and the blocking body is located at an initial position under the supporting effect of the water-soluble limiting structure to keep a gas production channel smooth; when the well section meets water, water enters the gas production channel and soaks the water-soluble limiting structure, and the water-soluble limiting structure is dissolved after meeting water to release the plugging body; the occluding body then moves to an occluding position, occluding the gas production passage.

In particular, the base pipe is a central pipe string, such as a water control screen or a blind pipe, for gas production in a gas well wellbore. The gas production channel is a gas channel for communicating the shaft with the interior of the central pipe column, and in the gas well exploitation process, gas produced in the matrix enters the central pipe column from the shaft through the gas production channel and is finally sent to the ground; obviously, if a certain well section in the shaft has a water outlet phenomenon, water can also enter the central pipe column through the gas production channel, so that the production is influenced, and the water control requirement is generated at the moment. When the blocking body is positioned at the initial position, the blocking body can be positioned inside the gas production channel, and also can be positioned outside, at the front end or on the side surface of the gas production channel, but the blocking body can not block the gas production channel, and the normal output of gas production can not be influenced. When water-soluble limit structure meets water and dissolves, releases the jam body, this moment the jam body under the effect of certain power (for example gravity, buoyancy, spring force, fluid driving force etc.), moves to the jam position (be about to the position that the gas production passageway closed), blocks the gas production passageway, perhaps closes the gas production passageway to effectively prevent water and get into central column through the gas production passageway, play the effect of "accuse water".

Considering that there may be a short-term water discharge in the downhole matrix (for example, in the early stage of production, the matrix may discharge a short-term amount of water due to the discharge of the drilling fluid absorbed therein, or, in the course of production, a small amount of water may be discharged indirectly), it is undesirable that the water-soluble spacer dissolves in water, since this would cause the production interval to fail and no longer produce gas, if the water discharge is not high. Thus, the length of time that the water soluble stop structure dissolves upon contact with water (i.e., the total length of time required from contact with water until release of the blocking device) can be set. Preferably, the dissolving time of the water-soluble limiting structure after meeting water is 3-1000 hours, the dissolving time can be flexibly set according to needs by combining the water outlet characteristic of a shaft and the drainage performance setting of a drainage channel described below. The dissolution time can be controlled by the material composition and/or shape of the water-soluble limiting structure.

On the other hand, for a small amount of water entering the gas production channel, the water can be directly discharged into the base pipe on the premise of not influencing normal production, so that the small amount of water is prevented from being deposited in the gas production channel, and the water-soluble limiting structure is dissolved in unexpected water. Preferably, a drainage channel for drainage may be provided below the gas production channel (where "below" refers to the direction of gravity of the gas well water control structure in use, or the direction in which water in the gas production channel flows downwards under the action of gravity, but not necessarily in a vertically downward direction), and the drainage channel may drain a small amount of water in the gas production channel into the base pipe, so as to avoid the water from undesirably dissolving the water soluble spacer structure. Preferably, the drainage channel is further provided with a flow control device, the flow control device is used for controlling the drainage speed of the drainage channel, and the drainage speed can be set on site according to the actual state of the gas well or different well sections of the gas well obtained by logging in advance when the central pipe column is lowered into the shaft, so that the blocking and closing time of the gas well or different well sections of the gas well can be adjusted and controlled. In particular, the flow control means may be means for varying the effective flow cross-sectional area of the drainage channel, such as a valve; or a sliding or rotatable blocking sheet blocked at the water inlet of the drainage channel; or a flap assembly with a through hole, removably arranged on the base pipe, said flap assembly having different specifications, differing in the diameter of said through hole as effective flow cross section.

The gas well water control structure based on the water-containing component can be pre-formed on the ground with a center pipe short section (such as a water control screen pipe short section or a blind pipe short section) forming a base pipe and then put into a well. One or more gas well water control structures based on water-containing solution components can be arranged on each short section so as to increase the gas production rate. Meanwhile, the upper structure (comprising the gas production channel, the water soluble limiting structure and the blocking body) and the lower structure (comprising the drainage channel and the flow control device) of the water control structure of the gas well based on the water soluble component can be in one-to-one correspondence relationship or not. For example, on one pup joint, 4 superstructures are circumferentially arranged to increase the gas production, but only one substructure is arranged for drainage.

When a part of the shaft produces water, the water produced by the part enters the water control structure of the gas well based on the water-containing component nearby, the structure responds, and the gas production channel is blocked, so that the water in the shaft of the water producing shaft is sealed outside the base pipe. Meanwhile, other well sections can still be normally exploited, so that the production efficiency of the gas well reaches the optimum.

Example 1:

this example presents a specific implementation of a water control structure for a gas well based on water-soluble components, particularly for vertical or directional wells.

As shown in fig. 1-8, a water control ring 2 and a filter sleeve 3 are arranged on the outer side of a base pipe 1, and a gas well water control structure 4 based on a water-containing component is arranged inside the water control ring 2 and the base pipe 1. Specifically, through holes corresponding in position are arranged inside the water control ring 2 and the base pipe 1 to form a gas production channel (as shown in the arrow direction in fig. 5; of course, the space between the base pipe 1 and the filter sleeve 3 can also be considered as belonging to a part of the gas production channel); a bell mouth-shaped throat pipe is arranged in the gas production channel, a spherical blocking body 4-3 is arranged at the front end (namely, the opening end) of the throat pipe at a certain distance, and the diameter of the blocking body 4-3 is larger than that of the gas production channel at the rear end of the throat pipe and smaller than that of the gas production channel at the front end of the throat pipe; a water-soluble limiting structure 4-2 is arranged at the throat, the water-soluble limiting structure 4-2 is a cylindrical structure, one end of the water-soluble limiting structure is supported on a plug 4-1 at the rear end of the throat, and the other end of the water-soluble limiting structure is supported on a blocking body 4-3 at the front end of the throat; the side wall of the blocking body 4-3 is provided with a hollow or through hole, or can be a sponge-like structure with pores filled inside, so that gas can pass through. When the water-soluble limiting structure 4-2 is dissolved after meeting water, the blocking body is released; then, the blocking body moves to a blocking position under the action of buoyancy or fluid thrust to block the gas production channel. The plug 4-1 is used for replacing the water-soluble limiting structure 4-2, so that the device can be repeatedly used. In addition, a flat baffle 4-4 is also arranged and fixed below the blocking body 4-3 to be matched with the water-soluble limiting structure 4-2 for use, and the blocking body 4-3 is positioned to be fixed at the initial position.

In general, the water-soluble limiting structure 4-2 may be in the shape of a plate, a tube, a rod, a cage, a sphere, or the like, and the blocking body 4-3 may be in the shape of an arc, a semicircle, a triangle, a sphere, a cone, or a trapezoid, and all of them should be considered as embodiments equivalent to the present embodiment.

Preferably, a drainage channel 5 is further provided on the sidewall of the base pipe 1 below the filter sleeve 3. The basic structure of the drainage channel 5 is a through hole arranged on the side wall of the base pipe 1, and the communication between the inner space of the filter sleeve 3 (namely the lower part of the gas production channel) and the inside of the base pipe 1 can be realized. When a small amount of water appears inside the filter sleeve 3 or inside the gas production channel, the water flows to the bottom of the filter sleeve 3 under the action of gravity and enters the base pipe through the drainage channel 5. Preferably, as shown in fig. 8, the drainage channel 5 is further provided with a flow control means for controlling the drainage rate.

A typical working process of a gas well water control structure based on a water-containing component is as follows: and (3) putting a base pipe with a gas well water control structure based on a water-soluble component into the directional vertical shaft, and simultaneously opening a plurality of underground gas reservoirs to produce. (1) In the initial stage of production, each layer only produces gas and does not produce water. (2) In the middle stage of production, a small amount of water is produced from one or more stratums, the produced water is taken away by the updraft and is produced from the shaft, the drainage channel 5 of the lower structure has reasonable design circulation capacity, the height of accumulated liquid in the filter sleeve 3 and the gas production channel cannot reach the height of the water-soluble limiting structure 4-2, the gas production channel cannot be blocked and closed, and the stratum cannot be influenced to continue gas production. (3) In the later stage of production, the water yield of one or more strata exceeds an allowable value, so that the water surface in the corresponding filter sleeve 3 and the gas production channel is raised until the water-soluble limiting structure 4-2 is reached and submerged, the water-soluble limiting structure 4-2 is dissolved when meeting water, the blocking body 4-3 is released, and the blocking body 4-3 moves upwards to the position of the throat pipe to block the gas production channel. Thereafter, the produced water and gas can enter the base pipe only through the lower drainage passage 5 (see fig. 8); because the drainage channel 5 has a smaller section relative to the gas production channel, the gas quantity and the water quantity entering the base pipe are reduced, and the harm of the local water outlet of the shaft to the gas well production is reduced. Preferably, a flow control means is installed in the drainage channel 5 of the substructure for controlling the rate of drainage.

Example 2:

this example shows another embodiment of a water control structure for a gas well based on a water-soluble component, which is particularly suitable for horizontal wells.

As shown in fig. 9-11, the base pipe 1 is arranged horizontally in the wellbore and the water control structure of the water-soluble component based gas well is preferably arranged on the upper side of the base pipe 1 (i.e. highest in the horizontal direction) with the aim of minimizing water entering the base pipe. Similar to the embodiment 1, the water control ring 2 and the base pipe 1 are internally provided with a gas production channel (as shown by the arrow in fig. 10); the difference is that the gas production channel is not provided with a throat pipe, but adopts a 90-degree right-angle bending structure. In an initial state, a plug 4-1, a spring 4-5, a blocking body 4-3 and a water-soluble limiting structure 4-2 are sequentially arranged in a gas production channel of the water control ring 2 (and a gas production channel at the front end of the bending part); the pipe plug 4-1 is arranged at one end or one side of the water control ring 2, and the inner side of the pipe plug is propped against a pre-extruded spring 4-5; the other end of the spring 4-5 is propped against the blocking body 4-3, and the other end of the blocking body 4-3 is limited in the water control ring 2 and is positioned at the right-angle bending part of the gas production channel. The water-soluble limiting structure 4-2 is also a hollow structure so as to ensure the smoothness of a gas production channel; of course, the water-soluble limiting structure 4-2 may also be a tubular, rod-shaped, cage-shaped, spherical, or the like structure. The structure of the blocking body 4-3 is provided with a pressure balancing hole, so that the pressure at two ends of the blocking body 4-3 is ensured to be equal, and the spring 4-5 is ensured to push the blocking body to move.

After the water-soluble limiting structure 4-2 is dissolved in water, the blocking body 4-3 moves towards the right-angle bending part of the gas production channel under the action of the spring 4-5, and the gas production channel is closed at the right-angle bending part by means of the side surface of the blocking body 4-3.

Example 3:

this example shows another embodiment of a water control structure for a gas well based on a water-soluble component, which is particularly suitable for horizontal wells.

As shown in fig. 12 to 14, the present embodiment differs from embodiment 2 only in that, firstly, the arrangement positions of the plug 4-1, the spring 4-5, the blocking body 4-3 and the water-soluble limiting structure 4-2 are different, namely, the plug 4-1, the water-soluble limiting structure 4-2, the blocking body 4-3 and the spring 4-5; the springs 4-5 are in a compressed state; the plug 4-1 and the water-soluble limiting structure 4-2 are also provided with a cylindrical flow guide body 4-6, and the flow guide body 4-6 is positioned at the right-angle bending part of the gas production channel; and secondly, one end of the blocking body 4-3 facing the flow guide body 4-6 is conical (certainly, the end can also be spherical or in other shapes), a plurality of axial channels are arranged in the blocking body, and the blocking body has the functional functions of axially conducting fluid and sealing a gas production channel by matching a conical tip with the flow guide body 4-6.

The working process of the gas well water control structure based on the water-containing component provided by the embodiment is as follows: after the water-soluble limiting structure 4-2 is dissolved in water, the blocking body 4-3 moves towards the right-angle bending part of the gas production channel under the action of the spring 4-5, and the conical tip of the blocking body is abutted against the flow guide body 4-6 to seal the gas production channel at the right-angle bending part.

Compared with the side wall blocking mode adopted in the embodiment 2, the conical top blocking mode adopted in the embodiment 3 can achieve better sealing effect.

Example 4:

this example shows another embodiment of a water control structure for a gas well based on water-soluble components, particularly for a vertical well.

As shown in fig. 15 to 17, this embodiment is different from embodiment 1 only in that the structure and position of the water soluble limiting structure 4-2 are different. Specifically, the water-soluble limiting structure 4-2 is a flat structure with sieve pores or through holes, the diameter of the water-soluble limiting structure is consistent with that of the gas production channel at the front end of the throat pipe, the water-soluble limiting structure is arranged in the gas production channel at the front end of the throat pipe and is matched with the baffle 4-4 for use, and the blocking body 4-3 is positioned to be at an initial position.

Example 5:

this example shows another embodiment of a water control structure for a gas well based on water-soluble components, particularly for a vertical well.

As shown in fig. 18-19, a water soluble limiting structure 4-2 is arranged at the front part (i.e. the air inlet end, the end communicated with the shaft) of the gas production channel or in the closed space formed by the base pipe 1 and the filter sleeve 3, and the water soluble limiting structure 4-2 is a cavity structure with a water soluble particle bin 7 in the middle. If the water-soluble limiting structure 4-2 is arranged at the front part of the gas production channel, the whole appearance is consistent with the front space of the gas production channel, and the water-soluble limiting structure can be cylindrical for example; meanwhile, an axial through hole is further formed in the cylindrical water-soluble limiting structure 4-2 and/or on the side wall of the cylindrical water-soluble limiting structure to serve as a gas channel, and the gas channel is isolated from the water-soluble particle bin 7. If the water-soluble limiting structure 4-2 is arranged in the closed space formed by the base pipe 1 and the filter sleeve 3, the arrangement mode is more flexible. The plugging bodies 4-3 are fine particles arranged in the water soluble particle bin 7, the density of the fine particles is less than that of formation water, and the diameter size of the plugging bodies is 0.1-5 mm. And a particle interception component 6 is arranged at the rear part of the gas production channel. The particle retention assembly 6 may be a screen structure with a mesh diameter smaller than the diameter of the occluding body 4-3. Preferably, the diameter of the rear portion of the gas production channel is smaller than the diameter of the front portion.

The working process of the gas well water control structure based on the water-containing component provided by the embodiment is as follows: (1) in an initial state, the water-soluble limiting structure 4-2 does not meet water, and the blocking body 4-3 is confined in the water-soluble particle bin 7 of the water-soluble limiting structure 4-2 to keep a gas production channel unblocked; (2) when the well section meets water, water enters the gas production channel and soaks the water-soluble limiting structure 4-2, and the water-soluble limiting structure 4-2 is dissolved after meeting water, so that the blocking body 4-3 in the water-soluble particle bin 7 is released; then, the blocking body 4-3 rises under the action of buoyancy and/or fluid pushing and is deposited at the front end of the particle interception component 6; as the amount of the clogging body 4-3 is deposited more and more, the gas production channel is eventually clogged and closed.

Example 6:

this example shows another embodiment of a water control structure for a gas well based on water-soluble components, particularly for a vertical well.

As shown in fig. 20-21, the gas production channel has a throat structure as shown in example 1; the water-soluble limiting structure 4-2 is a water-soluble stay wire structure, the plugging body 4-3 is a spherical structure with the density smaller than that of water, one end of the water-soluble stay wire is arranged at the bottom of the filter sleeve 3, and the other end of the water-soluble stay wire is connected with the plugging body 4-3.

The working process of the gas well water control structure based on the water-containing component provided by the embodiment is as follows: (1) in an initial state, the water-soluble limiting structure 4-2 does not meet water, the blocking body 4-3 and the water-soluble limiting structure 4-2 are located in a closed space formed by the base pipe 1 and the filter sleeve 3, and the gas production channel is unblocked. (2) When the air inlet channel meets water for a short time, the water-soluble limiting structure 4-2 needs a certain time to be dissolved, so that the water-soluble limiting structure 4-2 still has a limiting effect on the blocking body 4-3 at the moment, and the blocking body 4-3 is prevented from continuously rising under the action of buoyancy. (3) The water-soluble limiting structure 4-2 is dissolved and broken after reaching the preset time, and the blocking body 4-3 is released; the blocking body 4-3 rises under the action of buoyancy and fluid pushing force and is finally clamped at the throat of the gas production channel to block and seal the gas production channel.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.