Dewatering well plugging structure for high-pressure water-rich formations

Abstract

The present invention discloses a drainage well plugging structure for use in highly pressurized, water-rich formations. The structure is characterized by comprising: a plugging pipe connected to the wellhead of the drainage well, a water-stop ring disposed around the outer wall of the plugging pipe, a plugging cover, a rotating support symmetrically disposed on the inner wall of the plugging pipe, a rotating shaft rotatably connected to the rotating support at both ends, and a plugging ring. The present invention not only solves the problem of plugging drainage wells in highly pressurized, water-rich formations where water inflow is large and the pressure head is high after the main structure is constructed, but also prevents and addresses the situation where untimely pumping and drainage from the drainage wells during the construction of the main structure leads to large amounts of water inflow, thus affecting the construction of the main structure.

Description

Technical Field

[0001] The invention belongs to the technical field of auxiliary construction of dewatering well plugging, and in particular relates to a dewatering well plugging structure for high-pressure water-rich formations. Background Art

[0002] With the rapid development of my country's economic construction, underground engineering is in a stage of rapid development in my country, and underground engineering has become more popular. During the construction of underground engineering, groundwater dewatering is required to ensure the smooth and safe construction of the main structure. After the main structure construction is completed, the dewatering wells need to be sealed. During the dewatering well sealing process, there are two situations: one is that there is no water in the dewatering well or the water volume is small; the other is that the dewatering well has a large amount of water gushing out and is pressure-bearing. The former is relatively simple to seal, while the latter requires solving the problem of water gushing out, which is more difficult to seal.

[0003] In the prior art, a Chinese patent (CN202220607046.X) discloses a construction structure for plugging a dewatering well with high-pressure water. The structure comprises a water-absorbing hot-melt pipe inserted into the dewatering well with high-pressure water, an in-pipe plugging structure backfilled within the water-absorbing hot-melt pipe, an annular plugging structure backfilled between the dewatering well and the water-absorbing hot-melt pipe, and a top plugging structure disposed at the top of the water-absorbing hot-melt pipe. The bottom of the water-absorbing hot-melt pipe has an open section. This technology, by installing a water-absorbing hot-melt pipe within the dewatering well, absorbs and drains groundwater within the well, reducing the gushing water pressure and isolating the high-pressure underground water outside the annular plugging area. This allows the backfilling and plugging of the annular plugging area to be unaffected by the high-pressure underground water gushing in. This ensures the stability of the plugging structure within the annular plugging area, effectively reducing the inner diameter of the dewatering well, thereby reducing the difficulty of plugging the dewatering well and increasing the success rate of well plugging. However, this technical solution has the following disadvantages: when the amount of water gushing is very large and the pressure head is high, the water-absorbing hot-melt pipe is less effective in reducing the pressure of the gushing water, the gushing water cannot be fundamentally solved, and the sealing quality of the dewatering well cannot be guaranteed. In addition, the above technical solution can only be constructed after the main structure construction is completed and the conditions for dewatering well sealing are met. In high-pressure water-rich strata, the above-mentioned sealing construction structure cannot be constructed and take effect during the dewatering period of the main structure construction. It cannot deal with the situation where a large amount of water gushing occurs due to untimely pumping and drainage in the dewatering well due to unexpected circumstances, which affects the construction of the main structure. Summary of the Invention

[0004] In response to the above problems, the present invention provides a dewatering well sealing structure for high-pressure water-rich formations. It can not only solve the problem of sealing dewatering wells in high-pressure water-rich formations with large water gushing volume and high pressure head after the main structure construction is completed, but also prevent and deal with the situation during the dewatering period of the main structure construction, when the dewatering wells are not pumped out in time, resulting in a large amount of water gushing and affecting the main structure construction.

[0005] The present invention is achieved through the following technical solutions.

[0006] The dewatering well plugging structure for high-pressure water-rich formations is characterized by comprising: a plugging pipe connected to the wellhead of the dewatering well, a water stop ring arranged on the outer wall of the plugging pipe, a plugging plate, a rotating support symmetrically arranged on the inner wall of the plugging pipe, a rotating shaft rotatably connected to the rotating support at both ends, and a plugging ring;

[0007] The sealing ring includes a long arc segment water stop ring and a short arc segment water stop ring horizontally arranged along the inner wall of the sealing pipe; the arc ends of the long arc segment sealing ring are connected to one side of the rotating support, and the arc ends of the short arc segment water stop ring are connected to the other side of the rotating support, and the long arc segment water stop ring is located above the short arc segment water stop ring;

[0008] The sealing plate includes a lower sealing plate and an upper sealing plate arranged parallel to each other; the lower sealing plate is connected to one side of the rotating shaft, and the upper sealing plate is connected to the other side of the rotating shaft, so that the lower sealing plate and the upper sealing plate can rotate freely around the axis of the rotating shaft through the rotating support; when the lower sealing plate and the upper sealing plate are rotated to a horizontal position, the upper surface edge of the lower sealing plate abuts against the lower surface of the long arc segment water stop ring, and the lower surface edge of the upper sealing plate abuts against the upper surface of the short arc segment water stop ring, so that the wellhead of the dewatering well is blocked by the sealing plate and the sealing ring.

[0009] As a specific technical solution, a floating block is provided on one end of the lower surface of the lower sealing plate away from the rotation axis, and the floating block is used to provide buoyancy to form a rotational torque to make the lower sealing plate rotate clockwise around the rotation axis.

[0010] As a specific technical solution, when the lower sealing plate and the upper sealing plate are rotated to a horizontal position, the upper surface edge of the lower sealing plate abuts against the lower surface portion of the long arc segment sealing ring.

[0011] As a specific technical solution, the drainage well sealing structure of the present invention also includes a first pumping and draining pipe, which is arranged to pass through the long arc water stop ring from top to bottom, and a valve is provided at the upper end of the first pumping and draining pipe, and the lower end of the first pumping and draining pipe extends downward by 10 to 20 cm from the lower surface of the long arc water stop ring.

[0012] As a specific technical solution, the drainage well sealing structure of the present invention also includes a second drainage pipe, which runs through the short arc segment water stop ring from top to bottom, and a valve is provided at the upper end of the second drainage pipe. The lower end of the second drainage pipe extends downward from the lower surface of the short arc segment water stop ring. d ≥l, where l It is the maximum vertical distance between the edge of the lower sealing plate and the rotation axis.

[0013] As a specific technical solution, when the lower blocking plate rotates downward, the maximum angle between the lower blocking plate and the horizontal plane is 75°.

[0014] As a specific technical solution, the lower surface of the long arc segment water stop ring and the upper surface of the short arc segment water stop ring are covered with sealing rubber pads.

[0015] As a specific technical solution, the drainage well blocking structure of the present invention further includes a blocking plate control rod, one end of which is hinged to an end of the upper surface of the lower blocking plate away from the rotation axis.

[0016] As a specific technical solution, the sealing pipe is made of steel; the water stop ring and the sealing plate are made of steel plates.

[0017] As a specific technical solution, the height of the blocking pipe is 80 to 120 cm, and the outer diameter of the blocking pipe is the same as the inner diameter of the wellhead of the precipitation well.

[0018] The beneficial effects of the present invention are as follows:

[0019] 1) The present invention sets a plugging structure in the dewatering well and uses the bias pressure generated by the pressurized groundwater acting on the plugging structure to make the plugging steel plate fit tightly with the inner water-stop steel ring, and sets a sealing rubber pad between the plugging steel plate and the inner water-stop steel ring to enhance the sealing effect, thereby isolating the groundwater and providing a good working surface for the subsequent work of plugging the dewatering well. The present invention has a simple and effective principle, is easy to operate, and has low cost, and can well solve the problem of plugging dewatering wells in high-pressure water-rich formations.

[0020] 2) The present invention provides a floating block at one end of the lower sealing plate, so that the buoyancy of the floating block can be used to form a rotational torque to rotate the lower sealing plate clockwise around the rotation axis, so that the drainage well sealing structure is automatically closed, thereby preventing and responding to the situation during the drainage construction of the main structure, in which a large amount of water gushing is caused by untimely pumping and drainage in the drainage well, thereby affecting the construction of the main structure; at the same time, by providing a first drainage pipe and a second drainage pipe on the sealing ring, the first drainage pipe can facilitate the installation of a water pump for pumping and drainage, so that the drainage pipe of the water pump will not affect the rotation of the lower sealing plate, thereby ensuring that the floating block plays a role; and the second drainage pipe can pump and drain the gushing water from the drainage well in time, so that the floating block will not contact the gushing water and generate buoyancy, thereby ensuring that the lower sealing plate can rotate downward smoothly, so that the drainage well sealing structure is in an open state, so that the water pump can be taken out for inspection or replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of the present invention (the precipitation well blocking structure is in the open state);

[0022] Figure 2This is a schematic diagram of the structure of the present invention (the precipitation well blocking structure is in a closed state);

[0023] Figure 3 This is a schematic diagram of the structure of the present invention from a top view (the drainage well blocking structure is in a closed state, and the blocking plate control rod is not shown in the figure);

[0024] Figure 4 It is a schematic diagram of the top view of the structure of the present invention;

[0025] Figure 5 for Figure 3 Cross-sectional view at AA in the middle;

[0026] Figure 6 This is a schematic diagram of using the present invention to pump out water from a precipitation well during the dewatering period during the construction of the main structure;

[0027] Figure 7 This is a schematic diagram of using the present invention to seal a precipitation well after the main structure is completed;

[0028] Figure 8 This is a schematic diagram of using the second pumping and drainage pipe to pump out and drain water from the precipitation well;

[0029] The meanings of the symbols in the above figure are: dewatering well 1, sealing pipe 2, water stop ring 3, sealing ring 4, long arc segment sealing ring 401, short arc segment sealing ring 402, sealing rubber pad 403, rotating support 5, sealing plate 6, lower sealing plate 601, upper sealing plate 602, floating block 603, rotating shaft 7, first pumping and drainage pipe 8, valve 9, second pumping and drainage pipe 10, sealing plate control rod 11, water pump 12, and micro-expansive concrete 13. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Example 1

[0032] For use in high pressure water-rich formation dewatering well plugging structure, please refer to Figures 1 to 5 It includes: a plugging pipe 2 connected to the wellhead of the dewatering well 1, a water stop ring 3 arranged around the outer wall of the plugging pipe 2, a plugging plate 6, a rotating support 5 symmetrically arranged on the inner wall of the plugging pipe 2, a rotating shaft 7 rotatably connected to the rotating support 5 at both ends, and a plugging ring 4; preferably, the plugging pipe 2 is a circular pipe, the plugging ring 4 is an arc ring, the outer diameter of the plugging pipe 2 is 250-500 mm, the wall thickness is 2-5 mm, the width of the plugging ring 4 is 50-80 mm, and the thickness is 2-5 mm;

[0033] The sealing ring 4 includes a long arc segment sealing ring 401 and a short arc segment sealing ring 402 horizontally arranged along the inner wall of the sealing pipe 2; the two ends of the arc segment of the long arc segment sealing ring 401 are connected to one side of the rotating support 5, and the two ends of the arc segment of the short arc segment sealing ring 402 are connected to the other side of the rotating support 5, and the long arc segment sealing ring 401 is located above the short arc segment sealing ring 402, that is, the long arc segment sealing ring 401 and the short arc segment sealing ring 402 are connected end to end through the rotating support 5; preferably, the arc length of the long arc segment sealing ring 401 is 2 to 4 times the arc length of the short arc segment sealing ring 402;

[0034] The sealing plate 6 includes a lower sealing plate 601 and an upper sealing plate 602 arranged parallel to each other; the lower sealing plate 601 is connected to one side of the rotating shaft 7, and the upper sealing plate 602 is connected to the other side of the rotating shaft 7, so that the lower sealing plate 601 and the upper sealing plate 602 can rotate freely around the axis of the rotating shaft 7 through the rotating support 5; when the lower sealing plate 601 and the upper sealing plate 602 are rotated to a horizontal position, the upper surface edge of the lower sealing plate 601 abuts against the lower surface of the long arc segment sealing ring 401, and the lower surface edge of the upper sealing plate 602 abuts against the upper surface of the short arc segment sealing ring 402, so that the wellhead of the precipitation well is blocked by the sealing plate 6 and the sealing ring 4; preferably, the sealing plate 6 can be obtained by cutting a circular steel plate into a lower sealing plate 601 and an upper sealing plate 602, and then welding the lower sealing plate 601 and the upper sealing plate 602 to both sides of the rotating shaft 7 respectively;

[0035] When using the drainage well sealing structure of the present invention, the sealing pipe 2 can be inserted into the wellhead of the drainage well 1, so that the water stop ring 3 covers the wellhead of the drainage well 1; usually, the drainage well 1 is a steel pipe, and welding is performed at the joint between the water stop ring 3 and the drainage well 1. The weld should be full and no leaks should be allowed; please refer to Figure 6 During the construction of the main structure, the lower blocking plate 601 can be pressed down to open the blocking structure of the precipitation well. Then, the water pump 12 can be placed into the precipitation well through the blocking pipe 2 to pump out the precipitation. Figure 7When the main structure is completed and the conditions for sealing the precipitation well are met, the water pump can be taken out, and then the lower sealing plate 601 can be pulled up to close the precipitation well sealing structure. At this time, as the water in the precipitation well continues to gush out, when the water level in the precipitation well reaches the lower surface of the lower sealing plate 601, the pressure of the pressurized water in the precipitation well will push the lower sealing plate 601 upward, so that the sealing plate 6 and the sealing ring 4 can fit tightly to isolate the groundwater. Afterwards, micro-expansion concrete 13 can be poured in the sealing pipe 2 above the sealing plate 6, and the concrete grade should be one grade higher than the concrete of the main structure plate.

[0036] When the upper blocking plate 602 rotates downward, the edge of the upper blocking plate 602 may touch the inner wall of the blocking tube 2, thereby causing the upper blocking plate 602 to be unable to rotate downward smoothly (rotate counterclockwise). Further, in a preferred embodiment, please refer to Figure 2 and Figure 3 When the lower sealing plate 601 and the upper sealing plate 602 are rotated to a horizontal position, the upper edge of the lower sealing plate 601 abuts against the lower surface of the long arc segment sealing ring 401, so that a certain avoidance space is left between the edge of the lower sealing plate 601 and the inner wall of the sealing pipe 2, so as to increase the downward rotation angle of the lower sealing plate 601, thereby making the precipitation well sealing structure open and convenient for the installation and removal of the water pump; preferably, the width of the sealing ring 4 is 50 to 80 mm, and the abutment width between the upper edge of the lower sealing plate 601 and the lower surface of the long arc segment sealing ring 401 is 20 to 30 mm (along the width direction of the sealing ring 4).

[0037] Furthermore, in a preferred embodiment, a floating block 603 is fixedly provided on the lower surface of the lower blocking plate 601 at one end away from the rotating shaft 7, see Figure 1 and Figure 7 , the floating block 603 is used to provide buoyancy to form a rotational torque to make the lower sealing plate 601 rotate clockwise around the rotation axis 7; specifically, the floating block 603 can be made of a foam block or a plastic box with an internal vacuum to provide sufficiently large buoyancy; the size of the floating block 603 can be reasonably confirmed and selected according to the construction conditions on site; during the dewatering period of the main structure construction, if the water pump in the dewatering well works abnormally or the drainage passage is blocked, the gushing water in the dewatering well cannot be discharged in time, thereby causing the gushing water to enter the construction site and affect the construction of the main structure. Based on the setting of the above-mentioned structure of the present invention, even if the gushing water cannot be discharged in time, when the gushing water level reaches the position of the floating block 603, the floating block 603 can provide buoyancy to form a rotational torque to make the lower sealing plate 601 rotate clockwise around the rotation axis 7, thereby making the dewatering well sealing structure automatically closed (that is, the sealing plate 6 and the sealing ring 4 are tightly fitted), so that the gushing water will not gush out in large quantities and affect the construction of the main structure.

[0038] In order to prevent the water pump's suction pipe from affecting the clockwise rotation of the upper blocking plate 602 driven by the float 603, further, in a preferred embodiment, refer to Figure 1 and Figure 7 The drainage well sealing structure of the present invention also includes a first drainage pipe 8, which runs through the long arc segment sealing ring 401 from top to bottom and should avoid the abutment position between the long arc segment sealing ring 401 and the upper sealing plate 602; a valve 9 is provided at the upper end of the first drainage pipe 8, and the lower end of the first drainage pipe 8 extends downward by 10 to 20 cm from the lower surface of the long arc segment sealing ring 401; during precipitation, the upper sealing plate 602 can be rotated downward to open the drainage well sealing structure, and then the water pump is installed in the drainage well, and then the outlet pipe of the water pump is connected to the lower end of the first drainage pipe 8, and then a drainage pipe is connected to the outlet end of the first drainage pipe 8.

[0039] Further, in a preferred embodiment, see Figure 1 and Figure 8 The drainage well plugging structure of the present invention further includes a second drainage pipe 10, which is provided with a valve 9 at the upper end of the second drainage pipe 10 and extends downward from the lower surface of the short arc segment plugging ring 402. d ≥ l ,in l It is the maximum vertical distance between the edge of the lower sealing plate 601 and the rotation axis 7 (that is, when the lower sealing plate 601 is in a horizontal position and abuts against the lower surface of the long arc segment sealing ring 401, the vertical distance between its leftmost edge and the axis of the rotation axis 7); when the water gushing from the precipitation well cannot be discharged in time, although the float 603 can provide buoyancy to form a rotational torque to make the lower sealing plate 601 rotate clockwise around the rotation axis 7, thereby automatically closing the precipitation well sealing structure (that is, the sealing plate 6 and the sealing ring 4 are tightly fitted), it is necessary to rotate the lower sealing plate 601 downward at this time to open the precipitation well sealing structure. The water pump can be taken out for maintenance or replacement. However, due to the pressure of the pressurized water and the buoyancy of the float 603, it is difficult for the lower sealing plate 601 to rotate downward. In order to solve the above problem, an external water pump can be connected through the second drainage pipe 10 (the first drainage pipe 8 is already occupied at this time) to pump out the gushing water in the precipitation well, so that the water level of the precipitation well is lowered to a reasonable position, so as to facilitate the downward rotation of the lower sealing plate 601. When the lower sealing plate 601 is rotated downward to the lowest position, the float 603 is also at the lowest position, and the distance between the float 603 and the short arc segment sealing ring 402 is approximately equal to l， The lower end of the second drainage pipe 10 extends downward from the lower surface of the short arc segment sealing ring 402. d ≥ l，Therefore, after the gushing water in the precipitation well is pumped out through the second pumping and drainage pipe 10, the floating block 603 will not come into contact with the gushing water to generate buoyancy, thereby ensuring that the lower blocking plate 601 can rotate downward smoothly.

[0040] Further, in a preferred embodiment, see Figure 1 and Figure 8 When the lower blocking cover 601 rotates downward, the maximum angle between the lower blocking plate 601 and the horizontal plane is 75 degrees, so that the floating block 603 can smoothly drive the upper blocking plate 602 to rotate clockwise upward.

[0041] In order to make the sealing plate 6 and the sealing ring 4 fit closely together to achieve a better sealing effect, further, in a preferred embodiment, please refer to Figure 1 and Figure 2 The lower surface of the long arc segment sealing ring 401 and the upper surface of the short arc segment sealing ring 402 are covered with a sealing rubber pad 403.

[0042] In order to facilitate the control of the rotation of the lower blocking plate 601, further, in a preferred embodiment, refer to Figure 1 and Figure 2 The drainage well blocking structure of the present invention further includes a blocking plate control rod 11 , one end of which is hinged to an end of the upper surface of the lower blocking plate 601 away from the rotating shaft 7 .

[0043] Furthermore, in a preferred embodiment, the blocking tube 2 is made of steel; the water stop ring 3 and the blocking plate 6 are made of steel plates.

[0044] Furthermore, in a preferred embodiment, the height of the plugging pipe 2 is 80 to 120 cm, and the outer diameter of the plugging pipe 2 is the same as the inner diameter of the wellhead of the precipitation well.

Claims

1. A dewatering well plugging structure for high-pressure water-rich formations, characterized by include: A plugging pipe (2) for connecting to the wellhead of a dewatering well (1), a water stop ring (3) provided around the outer wall of the plugging pipe (2), a plugging plate (6), a rotating support (5) symmetrically provided on the inner wall of the plugging pipe (2), a rotating shaft (7) rotatably connected to the rotating support (5) at both ends, and a plugging ring (4); The blocking ring (4) comprises a long arc blocking ring (401) and a short arc blocking ring (402) arranged horizontally along the inner wall of the blocking tube (2); both ends of the arc of the long arc blocking ring (401) are connected to one side of the rotating support (5), and both ends of the arc of the short arc blocking ring (402) are connected to the other side of the rotating support (5), and the long arc blocking ring (401) is located above the short arc blocking ring (402); The blocking plate (6) comprises a lower blocking plate (601) and an upper blocking plate (602) which are arranged parallel to each other; the lower blocking plate (601) is connected to one side of the rotating shaft (7), and the upper blocking plate (602) is connected to the other side of the rotating shaft (7), so that the lower blocking plate (601) and the upper blocking plate (602) can rotate freely around the axis of the rotating shaft (7) through the rotating support (5); when the lower blocking plate (601) and the upper blocking plate (602) are rotated to a horizontal position, the upper surface edge of the lower blocking plate (601) abuts against the lower surface of the long arc segment blocking ring (401), and the lower surface edge of the upper blocking plate (602) abuts against the upper surface of the short arc segment blocking ring (402), so that the wellhead of the dewatering well is blocked by the blocking plate (6) and the blocking ring (4); A floating block (603) is provided at one end of the lower surface of the lower sealing plate (601) away from the rotation axis (7), and the floating block (603) is used to provide buoyancy to form a rotation torque to make the lower sealing plate (601) rotate clockwise around the rotation axis (7); The lower surface of the long arc segment sealing ring (401) and the upper surface of the short arc segment sealing ring (402) are covered with a sealing rubber pad (403).

2. The dewatering well plugging structure for high-pressure water-rich formations according to claim 1 is characterized in that It also includes a first drainage pipe (8), which is arranged to pass through the long arc segment sealing ring (401) from top to bottom, and a valve (9) is provided at the upper end of the first drainage pipe (8), and the lower end of the first drainage pipe (8) extends downward from the lower surface of the long arc segment sealing ring (401) by 10 to 20 cm.

3. The dewatering well plugging structure for high-pressure water-rich formations according to claim 2 is characterized in that The second drainage pipe (10) is also included. The second drainage pipe (10) is provided to pass through the short arc segment sealing ring (402) from top to bottom. A valve (9) is provided at the upper end of the second drainage pipe (10). The lower end of the second drainage pipe (10) extends downward from the lower surface of the short arc segment sealing ring (402). d ≥ l ,in l is the maximum vertical distance between the edge of the lower blocking plate (601) and the rotation axis (7).

4. The dewatering well plugging structure for high-pressure water-rich formations according to claim 2, characterized in that: When the lower blocking plate (601) rotates downward, the maximum angle between the lower blocking plate (601) and the horizontal plane is 75°.

5. The dewatering well plugging structure for high-pressure water-rich formations according to claim 1, characterized in that: It also includes a blocking plate control rod (11), one end of which is hinged to an end of the upper surface of the lower blocking plate (601) away from the rotation axis (7).

6. The dewatering well plugging structure for high-pressure water-rich formations according to claim 1, characterized in that: The blocking tube (2) is made of steel; the blocking ring (4) and the blocking plate (6) are made of steel plates.

7. The dewatering well plugging structure for high-pressure water-rich formations according to any one of claims 1 to 6, characterized in that: The height of the blocking pipe (2) is 80 to 120 cm, and the outer diameter of the blocking pipe (2) is the same as the inner diameter of the wellhead of the precipitation well.

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