CN219412550U - Extraction device for ground well mining area - Google Patents
Extraction device for ground well mining area Download PDFInfo
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- CN219412550U CN219412550U CN202221384022.9U CN202221384022U CN219412550U CN 219412550 U CN219412550 U CN 219412550U CN 202221384022 U CN202221384022 U CN 202221384022U CN 219412550 U CN219412550 U CN 219412550U
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Abstract
The extraction device for the mining area of the ground well sequentially comprises the following components from an extraction air inlet end to an exhaust end: the production sleeve, the wellhead reducing steel pipe, the wellhead valve, the elbow, the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator; an emptying pipe is arranged at the top end of the gas-water separator, and a water outlet is arranged at the bottom of the gas-water separator; the output end of the water ring vacuum pump is connected with the gas-water separator through a flange, and the input end of the water ring vacuum pump is connected with the explosion-proof tank through a flange; the output end of the explosion-proof tank is connected with the water ring vacuum pump through a flange, and the input end of the explosion-proof tank is connected with the backfire preventer through a flange; the output end of the backfire preventer is connected with the explosion-proof tank through a flange, and the input end of the backfire preventer is connected with the valve through a plurality of flanges; the output end of the valve is connected with the backfire preventer through a plurality of flanges, and the input end of the valve is connected with the wellhead reducing steel pipe through the flanges. The utility model comprises: the energy consumption of extraction is reduced, the construction efficiency is improved, the later maintenance is convenient, and meanwhile, the accident rate is completely eradicated, and the like.
Description
Technical Field
The utility model relates to a production casing device, in particular to a pumping device for a ground well mining area.
Background
The ground well extraction in the mining area is an important means for coal mine gas control and utilization. The coal mine gas control, gas emission reduction and utilization have great significance for realizing carbon peak and carbon neutralization. In the extraction process of the mining area, only the smoothness of the well body is kept, so that the guarantee can be provided for the extraction of the coal bed gas. Therefore, the extraction construction of the ground well mining area is necessarily applied to a casing production device, and the device mainly has the following functions:
1. and the supporting function is realized, the shearing, sliding, dislocation and blockage of the overlying strata of the coal bed are prevented, and the smooth drainage channel is ensured.
2. The holes of the production sleeve are sieve tubes, so that the air inlet channel at the bottom of the sleeve is increased, and the gas extraction amount of the ground well is increased under the same working condition of ground extraction equipment.
However, the current production sleeve device is fixed in the following manner: two-well structure and well cementation; current production sleeve pipe screen pipe section trompil design: the single hole is round, 6-8 holes are formed in each circle, and the opening ratio of the sieve tube is controlled to be 9-15%.
In the extraction process of the ground well in the mining area, the existing production casing device has the following design defects:
1. the conventional casing device is fixed in a two-well structure and well cementation mode, and well stability is general. The production sleeve is easy to transversely squeeze, tear, even break and other accidents due to the mining influence of the coal seam; the probability of damaging the supporting effect of the production sleeve device is high, and the supporting effect of the production sleeve device is damaged to influence the whole extraction work.
2. The existing production casing pipe sieve tube section is circular in holes, underground water vapor and dust are easy to gather at sieve holes, and the situation that the sieve holes are blocked by coal dust and rock dust occurs, so that extraction work is affected.
3. The number of holes of each circle of the screen pipe section of the existing production casing pipe is not specified, if the number of holes of each circle is even, the condition that the shearing stress direction is perpendicular to the connecting line of the central points of the opposite screen holes possibly exists, and compared with the screen pipes in other states, the screen pipe in the stress state has the worst shearing resistance, and is more easy to generate transverse dislocation accidents, so that the whole extraction work is influenced.
Disclosure of Invention
In order to solve the defects in the prior art, the utility model discloses a pumping device for a ground well mining area, which has the following technical scheme:
a take out and adopt device for ground well mining area sets gradually from taking out and taking in the end to exhaust end: the production sleeve, the wellhead reducing steel pipe, the wellhead valve, the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator; the method is characterized in that: an emptying pipe is arranged at the top end of the gas-water separator, and a water outlet is arranged at the bottom of the gas-water separator; the output end of the water ring vacuum pump is connected with the gas-water separator through a flange; the output end of the explosion-proof tank is connected with the input end of the water ring vacuum pump through a flange; the input end of the explosion-proof tank is connected with the output end of the backfire preventer through a flange; the input end of the anti-backfire device is connected with the output end of the wellhead valve through a plurality of flanges arranged on the ground extraction pipeline; and the input end of the wellhead valve is connected with the wellhead reducing steel pipe through a flange.
Preferably, it is: the inner diameters of the output end and the input end of the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator are the same as the inner diameter of the output end of the wellhead reducing steel pipe; the inner diameters of the production sleeve and the input end of the wellhead variable-diameter steel pipe are the same; the production sleeve is connected with the input end of the wellhead reducing steel pipe by adopting a screw thread.
Preferably, it is: the production sleeve consists of a solid pipe section and a screen pipe section, wherein the solid pipe section consists of a plurality of solid pipe production sleeves, and the screen pipe section consists of a plurality of screen pipe production sleeves; the solid pipe section and the screen pipe section are connected by screw threads.
Preferably, it is: the production sleeve fixing mode is as follows: three-well structure+well cementation, namely: the ground well is formed by a first well-opening section, namely a first well-opening section, a second well-opening section, namely a second well-opening section, and a third well-opening section, namely a third well-opening section from top to bottom; the well cementation comprises casing running and cement injection; the structural relation between the position of the well wall and the position of the production sleeve on the surface of the ground well and the fixing mode are as follows: the surface sleeve is fixed on the well wall through the one-way cementing cement sheath, the surface sleeve is fixed on the technical sleeve through the two-way cementing cement sheath, and the technical sleeve is fixed on the production sleeve through the three-way cementing cement sheath.
Preferably, it is: the solid section of the production casing is fixed on the technical casing by a three-opening well cementation cement ring, and the screen pipe section is exposed on the well wall.
Preferably, it is: 5 holes or 7 holes are formed in each circle of the production sleeve, and 20-25 rows of holes are formed in each 1 meter of production sleeve; the aperture ratio is controlled to 9-15%; the single hole has elliptic holes, the minor axis/major axis is 1/3-1/2, and the major axis is along the axial direction of the sleeve
Advantageous effects
The utility model discloses a ground well mining area extraction device, which comprises: the energy consumption of extraction is reduced, the construction efficiency is improved, the later maintenance is convenient, and meanwhile, the accident rate is completely eradicated, and the like.
1. The inner diameters of the input end, the output end and the ground pipeline of each extraction device on the ground are equal to the inner diameter of the output end of the wellhead variable-diameter steel pipe, and the inner diameters of the production sleeve and the input end of the wellhead variable-diameter steel pipe are equal; the friction resistance is reduced and the extraction energy consumption is reduced only by once diameter changing.
2. And all devices on the ground are connected by flanges, so that later-stage equipment debugging and overhaul are facilitated.
3. The production sleeve is connected by screw threads, and the mechanical operation can keep higher precision, so that the reliability and compactness of sleeve connection are improved; the thread connection part and the outer diameter of the sleeve are equal in width, so that the production sleeve can be ensured to smoothly enter the well.
4. The production sleeve is fixed in a three-well structure and well cementation mode, so that the stability of the well structure can be effectively improved, the probability of occurrence of accidents such as flattening and transverse dislocation of the sieve tube is reduced, the smoothness of the production sleeve is kept, and the guarantee is provided for coal bed gas extraction.
5. The solid pipe section of the production casing is fixed on the technical casing by a three-way cementing cement ring, so that the stability of the production casing is improved; the screen pipe section is exposed on the well wall, so that the air inlet channel at the bottom of the production sleeve is increased, and the gas extraction amount of the ground well is increased under the same working condition of the ground extraction equipment.
6. And (3) hole opening design of a production casing pipe section: the single hole is elliptical, the minor axis/major axis is 1/3-1/2, and the major axis is along the axial direction of the sleeve; according to the diameter of the production sleeve, 5 holes or 7 holes are formed in each circle, and the opening ratio of the sieve tube is controlled to be 9-15%. The coal powder blocking the sieve pores of the sieve tube in the extraction process can be effectively avoided.
Drawings
FIG. 1 is a schematic diagram of a production casing apparatus for extraction in a production zone of a surface well;
FIG. 2 is a schematic diagram of a production casing fixation pattern (three-well structure + well cementation);
FIG. 3 is a diagram showing the maximum shear stress of a screen with an even number (6) of holes per turn, wherein FIG. 3 (a) is a diagram showing the longitudinal stress of the screen; FIG. 3 (b) is a schematic view of lateral force applied to a screen; p represents shear stress, Q represents the maximum stress value of sieve mesh concentration;
FIG. 4 is a schematic illustration of screen openings (5 holes by 20 rows) per unit length, wherein FIG. 4 (a) is a schematic illustration of a screen; FIG. 4 (b) is a screen deployment schematic; the unit length is 1 meter.
Wherein: 1, emptying the pipe; 2 a first flange; 3, a concrete foundation; 4, pumping a pump room; 5 a second flange; 6, a valve; 7, cementing cement rings; 8, producing a sleeve solid pipe; 9, producing a sleeve screen pipe; 10 surface layer sleeve and 11 technical sleeve.
Description of the embodiments
The working process, principle, component structural design, component connection relation and beneficial effects of the utility model are described in four parts respectively.
A first part: the functions of each part of the adopted extraction device of the ground well mining area and the working process thereof.
A take out and adopt device for ground well mining area sets gradually from taking out and taking in the end to exhaust end: the production sleeve, the wellhead reducing steel pipe, the wellhead valve, the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator; the method is characterized in that: an emptying pipe is arranged at the top end of the gas-water separator, and a water outlet is arranged at the bottom of the gas-water separator; the output end of the water ring vacuum pump is connected with the gas-water separator through a flange; the output end of the explosion-proof tank is connected with the input end of the water ring vacuum pump through a flange; the input end of the explosion-proof tank is connected with the output end of the backfire preventer through a flange; the input end of the anti-backfire device is connected with the output end of the wellhead valve through a plurality of flanges arranged on the ground extraction pipeline; and the input end of the wellhead valve is connected with the wellhead reducing steel pipe through a flange. The inner diameters of the output end and the input end of the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator are the same as the inner diameter of the output end of the wellhead reducing steel pipe; the inner diameters of the production sleeve and the input end of the wellhead variable-diameter steel pipe are the same; the production sleeve is connected with the input end of the wellhead variable-diameter steel pipe by adopting a screw thread; the production sleeve consists of a solid pipe section and a screen pipe section, wherein the solid pipe section consists of a plurality of solid pipe production sleeves, and the screen pipe section consists of a plurality of screen pipe production sleeves; the solid pipe section and the screen pipe section are connected by screw threads.
And (3) producing a sleeve: and a channel for extracting gas to the ground in the underground mining area is formed, so that well stability is ensured, smooth extraction channels are ensured, and extraction work is smoothly carried out.
Wellhead reducing steel pipe: the inner diameters of the input end and the output end of the extraction devices on the ground with the inner diameters of the output end are equal; the inner diameter of the input end is equal to that of the production sleeve; the up-and-down communication is realized through one-time diameter changing.
Wellhead valve: the control part in the extraction system mainly has the functions of opening and closing the wellhead, and can play a role in adjusting when equipment is debugged.
Ground extraction pipeline: the ground channel extracted from the ground well mining area plays a role in stabilizing flow at the same time, so that the stable and accurate work of the detection system arranged on the ground channel is ensured.
Tempering prevention device: when the gas combustion accident occurs, the pressure in the pipe is reduced, and the fire at the combustion point can spread to the direction of the gas source through the pipeline, which is called tempering. The function of the anti-flashback device is to prevent and block such flashback.
Explosion-proof jar: when gas explosion accident occurs, the damage to surrounding personnel and articles caused by explosion can be prevented and weakened.
Water ring vacuum pump: belongs to a variable-capacity vacuum pump, and is characterized by that the suction, compression and exhaust are implemented by means of change of pump cavity volume. Is a power system of the whole set of extraction device in the extraction area of the ground well.
A gas-water separator: a device for separating gas from liquid. After gas-liquid separation, the gas is discharged from the top end evacuation pipe, and the liquid is discharged from the bottom water outlet.
The working process of the extraction device in the ground well mining area comprises the following steps:
1. preparation: detecting whether each device is normal or not, and preparing the device before extraction.
2. And (3) extraction work: starting a water ring vacuum pump, opening a wellhead valve, adjusting the pumping negative pressure stable working condition to pump, and sequentially passing the underground gas through: the production sleeve, the wellhead reducing steel pipe, the wellhead valve, the elbow, the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator.
3. Stopping the pump: and closing a wellhead valve, closing a water ring vacuum pump, and emptying accumulated water in the water ring vacuum pump and the gas-water separator.
A second part: the utility model adopts the composition of the production sleeve device, the connection relation and the fixing mode thereof.
Production sleeve component composition: the production casing consists of a solid pipe section and a screen pipe section, wherein the solid pipe section consists of a plurality of solid pipe production casings, and the screen pipe section consists of a plurality of screen pipe production casings.
Connection relationship between the production casing parts: the solid pipe section and the screen pipe section are connected by screw threads.
The production sleeve fixing mode is as follows: three-well structure and well cementation. The method comprises the following steps:
1. the ground well is formed by a first well-opening section (a first well-opening section), a second well-opening section (a second well-opening section) and a third well-opening section (a third well-opening section) from top to bottom. Cementing: comprising casing running and cementing
(1) The opening structure is as follows: and (3) completing drilling at a well opening section, putting a surface casing, and injecting cement into the annular space of the well wall and the surface casing to realize well cementation.
(2) The two-way structure is as follows: and (3) drilling the second well section, putting a technical sleeve, and injecting cement into the annular space of the technical sleeve, the well wall and the surface sleeve for second well cementation.
(3) The three-way structure is as follows: and (3) drilling the three-well section, putting the production sleeve into the well section, taking the bottom of the solid section of the production sleeve as the bottom of the artificial well, and injecting cement into the annular space between the production sleeve and the technical sleeve for three-well cementation.
2. The structural relation between the positions of the well wall and the production casing on the ground well plane and the fixing mode are as follows: the surface sleeve is fixed on the well wall through the one-way cementing cement sheath, the surface sleeve is fixed on the technical sleeve through the two-way cementing cement sheath, and the technical sleeve is fixed on the production sleeve through the three-way cementing cement sheath.
3. The solid section of the production casing is fixed on the technical casing by a three-opening well cementation cement ring, and the screen pipe section is exposed on the well wall.
Third section: and the adopted production casing pipe section is provided with a hole design.
1. The shape of the openings of the sieve holes is elliptical
If the sieve holes are round and square, in the extraction process, coal and rock are small, coal powder and water gas are mixed, and the sieve holes are easy to be blocked; if the sieve pore openings are rectangular and diamond-shaped, stress middle areas are easy to form at the turning corners of the sieve pores, and the compressive strength of the sieve tube is reduced. Oval open pores, and can effectively prevent the screen pipe from being blocked compared with round and square open pores; longer square, diamond shaped openings can effectively provide screen strength. So the optimal opening shape of the sieve pore of the production sleeve sieve tube section is elliptical.
2. The aperture ratio of the sieve holes is controlled to be 9-15%.
In the extraction process of the ground well mining area, along with underground stoping, a fracture zone on a goaf develops, and stress generated by rock stratum deformation is sheared and extruded to produce a casing screen section. Because the screen pipe is perforated, when the screen pipe receives the stress that the formation deformation produced, the stress concentration phenomenon can appear near the sieve mesh, greatly reduces compressive strength. Large aperture ratio, large extraction channel, small compression and tensile strength of the extraction sieve tube and vice versa.
According to the previous extraction construction of the ground well, the screen pipe opening ratio of the screen pipe section of the production casing pipe is controlled to be 9-15% as the optimal interval.
3. The number of holes of each circle of sieve tube is odd 5 holes or 7 holes.
If the number of openings in each circle is even, the shearing stress direction may be perpendicular to the connecting line of the central points of the opposite sieve holes; the screen pipe in the stress state has the worst shearing resistance, and is more prone to transverse dislocation accidents compared with the screen pipes in other states. To avoid this, the number of openings per revolution of the production sleeve is odd.
The number of holes of each circle of the production sleeve is odd, and 5 holes or 7 holes are formed in each circle according to the diameter of the production sleeve. If the number of the holes is less than 5 holes per circle, the single-hole aperture is required to be enlarged to ensure the aperture ratio, so that the compressive strength of the sieve tube is reduced; the number of holes is more than 7 holes per circle, the single hole diameter is required to be reduced in order to ensure the aperture ratio, and the sieve holes are easy to be blocked by mixing coal dust and water gas in the extraction process.
In summary, the production casing screen section openings are designed to: according to the diameter of the production sleeve, 5 holes or 7 holes are formed in each circle of the production sleeve, and 20-25 rows of holes are formed in each 1 meter of production sleeve; the aperture ratio is controlled to 9-15%; the single hole is elliptical, the minor axis/major axis is 1/3-1/2, and the major axis is along the axial direction of the sleeve.
Fourth, technical effects of the present utility model.
1. The production sleeve fixing mode adopts: three-well structure and well cementation. Compared with the prior casing device 'two-well structure + well cementation' fixing mode. The stability of the well body is improved, the probability of accidents such as transverse extrusion, tearing, even dislocation and the like of the production casing is reduced, and the smooth extraction work of the whole mining area is ensured.
2. The utility model provides a casing pipe sieve section perforating design: the single hole is elliptical, the minor axis/major axis is 1/3-1/2, and the major axis is along the axial direction of the sleeve. Compared with the existing production casing pipe sieve section circular holes, the situation that sieve holes are blocked by coal dust and rock dust is difficult to occur, and the smooth extraction work of the whole mining area is ensured.
3. The utility model provides a casing pipe sieve section perforating design: according to the diameter of the production sleeve, 5 holes or 7 holes are formed in each circle of the production sleeve, and 20-25 rows of holes are formed in each 1 meter of production sleeve. Compared with the prior production casing pipe, the number of holes of each circle of the screen pipe section of the production casing pipe is not specified, the probability of occurrence of transverse dislocation accidents of the production casing pipe with the odd number of holes of each circle is reduced, and the smooth extraction work of the whole mining area is ensured.
The foregoing has shown and described the basic principles, principal features and advantages of the utility model. It will be understood by those skilled in the art that the present utility model is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present utility model, and various changes and modifications may be made therein without departing from the spirit and scope of the utility model, which is defined by the appended claims. The scope of the utility model is defined by the appended claims and equivalents thereof.
Claims (1)
1. A take out and adopt device for ground well mining area sets gradually from taking out and taking in the end to exhaust end: the production sleeve, the wellhead reducing steel pipe, the wellhead valve, the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator; an emptying pipe is arranged at the top end of the gas-water separator, and a water outlet is arranged at the bottom of the gas-water separator; the output end of the water ring vacuum pump is connected with the gas-water separator through a flange; the output end of the explosion-proof tank is connected with the input end of the water ring vacuum pump through a flange; the input end of the explosion-proof tank is connected with the output end of the backfire preventer through a flange; the input end of the anti-backfire device is connected with the output end of the wellhead valve through a plurality of flanges arranged on the ground extraction pipeline; the input end of the wellhead valve is connected with the wellhead reducing steel pipe through a flange; the inner diameters of the output end and the input end of the ground extraction pipeline, the anti-backfire device, the anti-explosion tank, the water ring vacuum pump and the gas-water separator are the same as the inner diameter of the output end of the wellhead reducing steel pipe; the inner diameters of the production sleeve and the input end of the wellhead variable-diameter steel pipe are the same; the production sleeve is connected with the input end of the wellhead variable-diameter steel pipe by adopting a screw thread; the production sleeve consists of a solid pipe section and a screen pipe section, wherein the solid pipe section consists of a plurality of solid pipe production sleeves, and the screen pipe section consists of a plurality of screen pipe production sleeves; each production sleeve pipe of the solid pipe section and the screen pipe section is connected by screw threads; the method is characterized in that: the production sleeve fixing mode is as follows: three-well structure+well cementation, namely: the ground well is formed by a first well-opening section, namely a first well-opening section, a second well-opening section, namely a second well-opening section, and a third well-opening section, namely a third well-opening section from top to bottom; the well cementation comprises casing running and cement injection; the structural relation between the position of the well wall and the position of the production sleeve on the surface of the ground well and the fixing mode are as follows: the well wall is fixed with a surface sleeve through a one-way cementing cement sheath, the surface sleeve is fixed with a technical sleeve through a two-way cementing cement sheath, and the technical sleeve is fixed with a production sleeve through a three-way cementing cement sheath; the solid section of the production casing is fixed on the technical casing by a three-opening well cementation cement ring, and the screen pipe section is exposed on the well wall; 5 holes or 7 holes are formed in each circle of the production sleeve, and 20-25 rows of holes are formed in each 1 meter of production sleeve; the aperture ratio is controlled to 9-15%; the single hole is elliptical, the minor axis/major axis is 1/3-1/2, and the major axis is along the axial direction of the sleeve.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221384022.9U CN219412550U (en) | 2022-06-02 | 2022-06-02 | Extraction device for ground well mining area |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221384022.9U CN219412550U (en) | 2022-06-02 | 2022-06-02 | Extraction device for ground well mining area |
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| CN219412550U true CN219412550U (en) | 2023-07-25 |
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| CN202221384022.9U Active CN219412550U (en) | 2022-06-02 | 2022-06-02 | Extraction device for ground well mining area |
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- 2022-06-02 CN CN202221384022.9U patent/CN219412550U/en active Active
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