CN220246982U - Active foundation pit dewatering pneumatic pumping system - Google Patents

Abstract

The utility model relates to an active foundation pit dewatering pneumatic pumping system. A pneumatic water pump is arranged at the bottom of the downcomer well, a wellhead control box is arranged at the wellhead position, and a compressed gas supply device and an air extractor are also arranged on the ground; the wellhead control box comprises a box body, a first pneumatic electromagnetic valve, a second pneumatic electromagnetic valve and a pressure regulating valve, wherein the first pneumatic electromagnetic valve, the second pneumatic electromagnetic valve and the pressure regulating valve are arranged in the box body, and two air outlets of the pressure regulating valve are respectively connected with air inlets of the first pneumatic electromagnetic valve and the second pneumatic electromagnetic valve; the pneumatic water pump comprises a baffle plate with a water drain pipe in the middle, semi-cylindrical shells are arranged on two sides of the baffle plate, air passage connecting pipes are arranged on top walls of the two shells, drain ports are arranged on bottom walls of the two shells, drain covers are arranged on the bottom sides of the water drain pipe, check valves in the shells are arranged on the two sides of the bottom of the water drain pipe, the bottom of the side wall of the two shells is provided with a shell check valve, and a water drain pipeline is connected to the water drain pipe and extends out of a well. The utility model has reasonable structural design, high dewatering and drainage efficiency and long-acting operation.

Description

Active foundation pit dewatering pneumatic pumping system

Technical Field

The utility model belongs to the technical field of drainage equipment, and particularly relates to an active foundation pit dewatering pneumatic drainage system.

Background

In some building construction and environmental protection construction fields, foundation pit excavation and dewatering and drainage operations are generally required. Pipe well dewatering is a common dewatering and drainage operation method, and accumulated water continuously enters the dewatering pipe well and is drained by arranging the dewatering pipe well in the area where a foundation pit is located and arranging a water pumping facility in the dewatering pipe well.

Under some specific geological conditions, a foundation pit is excavated on the ground, a water-reducing pipe well is arranged in the foundation pit, and the water is difficult to achieve the purpose of water reduction by means of the treatment mode of automatically collecting water into the water-reducing pipe well under the self-flowing and penetrating actions of the water body in the soil layer, and the root cause is that: under specific special conditions, the water in the soil layer is difficult to automatically flow into the water-reducing pipe well. The technical means applied at this time is to seal the dewatering pipe well and reduce the air pressure in the dewatering pipe well by adopting a vacuumizing mode, and the water in the soil layer is forced to permeate and flow into the well by establishing pressure difference, so that dewatering and drainage are possible. However, the aforementioned manner of creating a low pressure in the well creates a problem in the manner of performing well dewatering and drainage operations based on pneumatic water pumps: because the well is in a low pressure condition, the inner cavity of the pneumatic water pump is in a normal pressure condition, so that the water pump check valve which can be opened by the gravity action of the water collected in the well originally cannot be opened by itself, the water collected in the well cannot enter the water pump, and precipitation and drainage failure are caused. The air suction and the water discharge in the well can be alternately performed to solve the problems, the water discharge in the soil layer is only promoted in the stage of reducing the air pressure in the well and maintaining the pressure, when a certain amount of water is collected in the well, the air suction effect is removed to enable the well to recover to normal pressure, at the moment, the pneumatic water pump can smoothly perform the water discharge operation, and the air suction and the pressure maintaining are performed again after the water discharge is completed. However, the foregoing processing method has the following problems: the process of establishing low pressure for a downcomer well is a relatively lengthy process, repeating the foregoing operation will result in reduced precipitation efficiency, and the process of maintaining pressure in the well is a process of promoting drainage of water in the soil layer, and destruction of the foregoing process will also result in poor drainage of water.

Therefore, the structure of the foundation pit dewatering pumping system needs to be optimally designed to solve the technical problems.

Disclosure of Invention

The utility model provides an active type pneumatic dewatering and drainage system for a foundation pit, which is reasonable in structural design, high in dewatering and drainage efficiency and capable of running for a long time, and solves the technical problems in the prior art.

The utility model adopts the technical proposal for solving the technical problems in the prior art that: an active foundation pit dewatering pneumatic pumping system is characterized in that a sealing well cover is arranged at a well mouth of a dewatering pipe well; a pneumatic water pump is arranged at the bottom of the downcomer well, a wellhead control box is arranged at the wellhead position, and a compressed gas supply device and an air extractor are also arranged on the ground; the wellhead control box comprises a box body, a first pneumatic electromagnetic valve, a second pneumatic electromagnetic valve and a pressure regulating valve, wherein the first pneumatic electromagnetic valve, the second pneumatic electromagnetic valve and the pressure regulating valve are arranged in the box body, and two air outlets of the pressure regulating valve are respectively connected with air inlets of the first pneumatic electromagnetic valve and the second pneumatic electromagnetic valve; the pneumatic water pump comprises a baffle plate with a water drain pipe in the middle, semi-cylindrical shells are arranged on two sides of the baffle plate, air passage connecting pipes are arranged on top walls of the two shells, drain ports are arranged on bottom walls of the two shells, drain covers are arranged on the bottom of the water drain pipe, check valves in the shells are arranged on two sides of the bottom of the water drain pipe, the shell check valves are arranged on the bottoms of the side walls of the two shells, and a water drain pipeline is connected to the water drain pipe and extends out of a well; the compressed gas supply device is connected to the air inlet of the pressure regulating valve through a gas pipeline, the two gas path connecting pipes are respectively connected with the air outlets of the first pneumatic electromagnetic valve and the second pneumatic electromagnetic valve through water pump air pipes, and the air outlet of the wellhead control box is connected to the air extractor; the system also comprises a well exhaust pipe communicated with the interior of the water reducing pipe well, and the well exhaust pipe is connected to the air extractor.

Preferably: the shell check valve comprises a fixed valve plate with a window in the middle and a movable valve plate hinged on the inner side of the window of the fixed valve plate, a permeable window is arranged on the shell, the fixed valve plate is positioned in the permeable window, the two side edges of the fixed valve plate are welded with the two side edges of the permeable window in a sealing way, and a sealing plate is welded between the upper and lower edges of the fixed valve plate and the upper and lower edges of the permeable window in a sealing way; a filter screen is also arranged on the water permeable window.

Preferably: an upper hinge and a lower hinge are arranged between the fixed valve plate and the movable valve plate, the hinges comprise a fixed rotating shaft arranged on the fixed valve plate by adopting a shaft seat and a movable rotating shaft arranged on the movable valve plate by adopting a shaft seat, and a connecting plate is arranged between the fixed rotating shaft and the movable rotating shaft.

Preferably: the check valve in the shell comprises a valve body with a valve port at the bottom, an inner cavity of the valve body is communicated with an inner cavity of the drain pipe, and a check diaphragm which only allows seepage to pass upwards is arranged on the valve port.

Preferably: the box body of the wellhead control box is provided with a control box air inlet interface, two air outlet interfaces and two air supply interfaces, the control box air inlet interface is connected with an air inlet of the pressure regulating valve, the two air outlet interfaces are respectively connected with air outlets of the first pneumatic electromagnetic valve and the second pneumatic electromagnetic valve, and the two air supply interfaces are respectively connected with air outlets of the first pneumatic electromagnetic valve and the second pneumatic electromagnetic valve.

Preferably: the electromagnetic valve is arranged at the connection position of the air pipe of the water pump and the wellhead control box, the electromagnetic valve is arranged on the air path between the air outlet of the wellhead control box (7) and the air extractor (9), and the electromagnetic valve is arranged at the connection position of the well air extraction pipe and the air extractor.

Preferably: the compressed air supply device comprises an air source filter, an air compressor and an air storage tank, wherein an outlet of the air source filter is connected to an inlet of the air compressor, and an outlet of the air compressor is connected to an inlet of the air storage tank.

The utility model has the advantages and positive effects that:

compared with the existing foundation pit dewatering and drainage system based on the pneumatic water pump, the foundation pit dewatering and pneumatic drainage system provided by the utility model adopts the air extractor to perform air extraction and decompression in the dewatering pipe well, and promotes the water in the soil layer to enter the well, so that the foundation pit dewatering and pneumatic drainage system is an active drainage system. Meanwhile, the air extractor can be connected with the pneumatic water pump, and the inner cavity of the pneumatic water pump is subjected to air extraction and pressure reduction treatment to ensure that the inner cavity of the pneumatic water pump and the inner cavity of the water pump are kept in the same low-pressure condition, so that the water collecting energy in the well can force the valve on the pneumatic water pump to be opened and smoothly enter the inner part under the action of self gravity, the system can finish the drainage operation under the low-pressure condition, the built low-pressure condition in the well is not required to be destroyed in the whole process of executing the drainage operation, and the system is favorable for ensuring that the inner cavity is in a long-acting dewatering promoting condition and effectively promoting the water in the soil layer to flow in the well.

By arranging the wellhead control box, the pneumatic water pump is finely controlled, after water collected in the well enters the water pump, the compressed air source is injected into the water pump, so that the air pressure in the water pump is increased, the water collected in the water pump is forced to be discharged out of the well through the drainage pipeline, and therefore, the active foundation pit dewatering pneumatic pumping system can efficiently discharge dewatering in the well.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a schematic view of the external structure of the pneumatic water pump of FIG. 1;

FIG. 3 is a schematic view of the internal structure of the pneumatic water pump of FIG. 1;

FIG. 4 is a schematic view of the structure of the check valve of the housing of FIG. 1;

fig. 5 is a schematic view of the wellhead control cartridge of fig. 4.

In the figure:

1. a water-reducing pipe well; 2. a pneumatic water pump; 2-1, a shell; 2-2, a separator; 2-3, a drain pipe; 2-4, connecting the air channel; 2-5, a filter screen; 2-6, a check valve in the shell; 2-7, a sewage draining cover; 2-8, fixing a valve plate; 2-9, a movable valve plate; 2-10, a hinge; 3. a water pump air pipe; 4. sealing the well cover; 5. a drainage pipe; 6. a well extraction tube; 7. a wellhead control box; 7-1, a box body; 7-2, an exhaust interface; 7-3, a first pneumatic solenoid valve; 7-4, an air supply interface; 7-5, a second pneumatic electromagnetic valve; 7-6, a pressure regulating valve; 7-7, controlling the air inlet interface of the box; 8. compressed gas supply means; 9. and (5) an air extractor.

Detailed Description

In order to further understand the summary, features and advantages of the present utility model, the following examples are set forth in detail.

Referring to fig. 1, the active foundation pit dewatering pneumatic pumping system of the utility model is provided with a sealing well cover 4 at the wellhead of a dewatering pipe well 1, and the inner cavity of the dewatering pipe well 1 is closed by installing the sealing well cover 4, so that the internal air pressure can be reduced by pumping out air. The bottom of the downcomer well 1 is provided with a pneumatic water pump 2, a wellhead control box 7 is arranged at the wellhead position, and a compressed gas supply device 8 and an air extractor 9 are also arranged on the ground.

The working principle is as follows: the inside of the downcomer well 1 is pumped and decompressed by adopting the air extractor 9, the water in the soil layer is promoted to be discharged and enter the downcomer well 1 by establishing a pressure difference, the inside of the pneumatic water pump 2 is pumped and decompressed by adopting the air extractor 9 under the pressure maintaining state, the low pressure condition in the water pump is the same as the low pressure condition in the well, the water collection in the well can force the valve on the water pump to be opened and enter the valve under the action of the gravity, then the compressed air source supplied by the compressed air supply device 8 enters the inside of the pneumatic water pump 2 under the control action of the wellhead control box 7, the inside of the water pump is converted into a high pressure state, and the water collection in the inside is discharged out of the well through the pneumatic water pump 2 under the high pressure condition; in the whole dewatering and drainage operation process, the low-pressure environment established in the well can not be destroyed, the water in the soil layer continuously flows out, and the dewatering and drainage efficiency of the foundation pit is ensured.

In this embodiment, the compressed air supply device 8 includes an air source filter, an air compressor, and an air tank, wherein an outlet of the air source filter is connected to an inlet of the air compressor, and an outlet of the air compressor is connected to an inlet of the air tank. The air source filter is used for filtering an air source, improving the quality of the air source, the air compressor is used for compressing air to generate a compressed air source, and the air storage tank is used for storing the compressed air source.

Referring to fig. 3, 4 and 5, it can be seen that:

the pneumatic water pump 2 comprises a partition plate 2-2 with a water drain pipe 2-3 in the middle, semi-cylindrical shells 2-1 are arranged on two sides of the partition plate 2-2, air passage connecting pipes 2-4 are arranged on the top walls of the two shells 2-1, and drain outlets and drain covers 2-7 are arranged on the bottom walls.

The pneumatic water pump 2 is integrally in a cylindrical shape, the inner cavity of the pneumatic water pump is divided into a left cavity and a right cavity by the partition plate 2-2, the drain pipes 2-3 are used as common drain pipes of the two cavities, the top wall of each cavity is provided with an air passage connecting pipe 2-4, the air passage connecting pipe 2-4 is connected to the wellhead control box 7 through an air passage, and the bottom wall of each cavity is provided with a drain outlet and a drain cover 2-7. After a certain period of use, the pneumatic water pump 2 is lifted out of the well, the blowdown cover 2-7 is disassembled to discharge mud in the well, and the inside can be flushed by adopting a high-pressure water gun.

The two sides of the bottom of the drain pipe 2-3 are provided with the in-shell check valves 2-6, and the bottoms of the side walls of the two shells 2-1 are provided with the shell check valves. As shown in the figure, two in-shell check valves 2-6 are respectively positioned in two chambers, the function of the shell check valves is to enable seepage collected in a well to only enter the two chambers of the pneumatic water pump 2 unidirectionally and not flow into the well from the chambers of the pneumatic water pump 2, and the function of the in-shell check valves 2-6 is to enable seepage in the chambers of the water pump to only enter the drain pipe 2-3 unidirectionally and not flow into the chambers of the water pump from the drain pipe 2-3.

In the embodiment, the one-way valve 2-6 in the shell comprises a valve body with a valve port at the bottom, the inner cavity of the valve body is communicated with the inner cavity of the drain pipe 2-3, and a one-way diaphragm which only allows seepage to pass upwards is arranged on the valve port. Specifically, the valve body of the check valve 2-6 in the shell is welded and arranged at two sides of the bottom of the drain pipe 2-3, when the air pressure in the water pump cavity is increased, the seepage in the cavity forces the one-way diaphragm to be opened upwards under the action of the air pressure, the seepage enters the drain pipe 2-3, along with the fact that the compressed air source further enters the water pump cavity, the seepage is continuously discharged through the drain pipe 2-3, when the air pressure in the water pump cavity is eliminated, under the action of gravity, the seepage in the drain pipe 2-3 enables the one-way diaphragm of the check valve 2-6 in the shell to be closed downwards, and therefore seepage in the drain pipe 2-3 cannot flow back.

A drain pipe 5 is connected to the drain pipe 2-3 and the drain pipe 5 extends to the outside of the well, as shown in the figure, the drain pipe 5 penetrates through the sealing manhole cover 4, specifically, a pipe hole is provided on the sealing manhole cover 4 and the drain pipe 5 penetrates through the pipe hole, and a gap between the pipe hole and the drain pipe 5 is sealed by providing a sealant or the like.

Referring to fig. 3 and 4, it can be seen that:

the shell check valve comprises a fixed valve plate 2-8 with a window in the middle and a movable valve plate 2-9 hinged on the inner side of the window of the fixed valve plate 2-8, a permeable window is arranged on the shell 2-1, the fixed valve plate 2-8 is positioned in the permeable window, two side edges are welded with two side edges of the permeable window in a sealing way, and a sealing plate is welded between the upper and lower edges of the fixed valve plate 2-8 and the upper and lower edges of the permeable window in a sealing way.

The shell check valve is a check valve for providing a filtering function, filtered water transversely enters into the two chambers of the pneumatic water pump 2, and when the internal air pressure is increased, the shell check valve closes the water permeable window to prevent seepage in the chambers from transferring outwards.

In this embodiment, as shown in the figure, an upper hinge 2-10 and a lower hinge 2-10 are installed between a fixed valve plate 2-8 and a movable valve plate 2-9, the hinges 2-10 comprise a fixed rotating shaft installed on the fixed valve plate 2-8 by adopting a shaft seat and a movable rotating shaft installed on the movable valve plate 2-9 by adopting a shaft seat, and a connecting plate is arranged between the fixed rotating shaft and the movable rotating shaft.

Under the action of external water pressure, the movable valve plates 2-9 are opened inwards to open the window, and under the action of internal air pressure, the movable valve plates 2-9 are moved outwards to close the window. Under the action of the upper hinge 2-10 and the lower hinge 2-10, when the movable valve plate 2-9 moves inwards or outwards, the plate body of the movable valve plate is kept parallel to the fixed valve plate 2-8.

In order to ensure that the position of the water permeable window is not leaked when the shell one-way valve is closed, a sealing gasket is arranged between the fixed valve plate 2-8 and the movable valve plate 2-9, after the internal air pressure is increased, the movable valve plate 2-9 is extruded outwards, the sealing gasket deforms, and the water inlet window is ensured to be airtight.

The filter screen 2-5 is also arranged on the water permeable window, and the seepage liquid in the external well transversely passes through the shell one-way valve and enters the water pump cavity through the filter screen 2-5, so that large-particle sundries contained in the seepage liquid are trapped outside the water pump, and the problem of blockage of the water pump and subsequent pipelines is avoided.

Referring to fig. 5, it can be seen that:

the wellhead control box 7 includes a box body 7-1, and a first pneumatic solenoid valve 7-3, a second pneumatic solenoid valve 7-5 and a pressure regulating valve 7-6 provided in the box body 7-1, as shown in the drawing, both the first pneumatic solenoid valve 7-3 and the second pneumatic solenoid valve 7-5 are overlapped to reduce occupation of an inner space, and to promote a level of compactness of the wellhead control box 7. The top of the box body 7-1 is open and is provided with a detachable box cover.

The two air outlets of the pressure regulating valve 7-6 are respectively connected with the air inlets of the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5. The function of the pressure regulating valve 7-6 is that: the pressure regulating valve 7-6 can regulate the pressure of the air pressure, thereby changing the lift and enabling the seepage drainage system to be suitable for seepage drainage wells 14 with different depths. As shown in the figure, the regulating end of the pressure regulating valve 7-6 extends out from an operation window arranged on the box cover so as to regulate the flow, an indicator for displaying the opening degree is also arranged on the pressure regulating valve 7-6, and an observation window for exposing the indicator is arranged on the box cover.

In this embodiment, a box body 7-1 of the wellhead control box 7 is provided with a control box air inlet interface 7-7, two air outlet interfaces 7-2 and two air supply interfaces 7-4, the control box air inlet interface 7-7 is connected with an air inlet of the pressure regulating valve 7-6, the two air outlet interfaces 7-2 are respectively connected with air outlets of the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5, and the two air supply interfaces 7-4 are respectively connected with air outlets of the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5. The control box air inlet interface 7-7 of each wellhead control box 7 is connected with a compressed air source through a pipeline.

The compressed air source is delivered to the pressure regulating valve 7-6 through the air inlet interface 7-7 of the control box, the pressure regulating valve 7-6 divides the air source into two paths and outputs the two paths to the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5 respectively, when the pneumatic electromagnetic valve is controlled to enter the air supply state, the compressed air source supplies output to the pneumatic water pump 2 from the air outlet of the pneumatic electromagnetic valve, and when the pneumatic electromagnetic valve is controlled to enter the air exhaust state, the compressed air source in the pneumatic water pump 2 returns to the pneumatic electromagnetic valve.

The compressed air supply device 8 is connected to the air inlet of the pressure regulating valve 7-6, that is, to the control box air inlet interface 7-7 through an air pipeline, and the two air path connecting pipes 2-4 of the pneumatic water pump 2 are respectively connected with the air outlets of the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5 through the water pump air pipe 3, and the air outlets of the wellhead control box 7, that is, the air outlets of the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5 are connected to the air extractor 9. Also included is a well extraction tube 6 communicating with the interior of the downcomer well 1, the well extraction tube 6 being connected to an extractor 9. As shown in the figure, two water pump air pipes 3 and a well pumping pipe 6 pass through the sealing well cover 4.

In this embodiment, electromagnetic valves are arranged at the positions where the two water pump air pipes 3 are connected with the wellhead control box 7, electromagnetic valves are arranged on the air paths between the two air outlets of the wellhead control box 7, namely the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5, and the air pump 9, and electromagnetic valves are arranged at the positions where the well air extraction pipe 6 is connected with the air pump 9, so that the air paths can be gated by arranging a plurality of electromagnetic valves, and the working states of the system, namely the air extraction and decompression state of the downcomer well 1, the air extraction and decompression state of the pneumatic water pump 2 and the supercharging and drainage state of the pneumatic water pump 2 are adjusted.

The automatic control system also comprises a controller, wherein the controller is constructed based on the PLC, and the electromagnetic valve on each air path and the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5 of the wellhead control box 7 are connected with the controller and are subjected to field control of the controller to realize automatic operation.

The working mode is as follows:

excavating a water-reducing pipe well 1, and installing the active foundation pit drainage pneumatic pumping system and a sealing well cover 4 on the water-reducing pipe well 1;

the first step is to pump air and decompress the water-reducing pipe well 1, the controller controls each electromagnetic valve to act, only the conduction between the well pumping pipe 6 and the air pump 9 is kept, the air pump 9 is started to pump air and decompress the well, and the water in the surrounding soil layer is forced to flow into the well by establishing pressure difference in the well; the second step is to pump air and decompress the pneumatic water pump 2, the controller controls each electromagnetic valve to act, only keep the conduction between two water pump air pipes 3 and air pump 9 (the first pneumatic electromagnetic valve 7-3 and second pneumatic electromagnetic valve 7-5 act, the well head control box 7 enters the exhaust mode), start the air pump 9 to pump air and decompress the water pump, when the low pressure condition in the pneumatic water pump 2 is consistent with the low pressure condition in the well, the shell check valve can be opened inwards by the gravity of the water body, the water gathered in the well smoothly enters the inside of the pneumatic water pump 2; the third step is the drainage operation, the controller controls the action of each electromagnetic valve, the air extractor 9 is disconnected with the water pump air pipe 3, the water pump air pipe 3 is connected with the compressed air supply device 8 through the wellhead control box 7 (the first pneumatic electromagnetic valve 7-3 and the second pneumatic electromagnetic valve 7-5 act, the wellhead control box 7 enters the air supply mode), the compressed air source supplied by the compressed air supply device 8 enters two chambers of the pneumatic water pump 2 through the wellhead control box 7 and the water pump air pipe 3, the pressure is increased in the two chambers, the water body upwards enters the drainage pipeline 5 through the one-way valve 2-6 and the drainage pipe 2-3 in the shell under the pressure, and finally the water body is discharged outside the well, so that the whole working cycle is achieved.

Claims (7)

1. An active foundation pit dewatering pneumatic pumping system is characterized in that a sealing well cover (4) is arranged at the wellhead of a dewatering pipe well (1); the method is characterized in that: a pneumatic water pump (2) is arranged at the bottom of the downcomer well (1), a wellhead control box (7) is arranged at the wellhead position, and a compressed gas supply device (8) and an air extractor (9) are also arranged on the ground;

the wellhead control box (7) comprises a box body (7-1), a first pneumatic electromagnetic valve (7-3), a second pneumatic electromagnetic valve (7-5) and a pressure regulating valve (7-6) which are arranged in the box body (7-1), wherein two air outlets of the pressure regulating valve (7-6) are respectively connected with air inlets of the first pneumatic electromagnetic valve (7-3) and the second pneumatic electromagnetic valve (7-5); the pneumatic water pump (2) comprises a baffle plate (2-2) with a water drain pipe (2-3) in the middle, semi-cylindrical shell bodies (2-1) are arranged on two sides of the baffle plate (2-2), a gas path connecting pipe (2-4) is arranged on the top wall of each of the two shell bodies (2-1), a drain outlet is arranged on the bottom wall, a drain cover (2-7) is arranged on each of the bottom wall, check valves (2-6) in the shell are arranged on two sides of the bottom of the water drain pipe (2-3), shell check valves are arranged on the bottoms of the side walls of the two shell bodies (2-1), a water drain pipeline (5) is connected to the water drain pipe (2-3), and the water drain pipeline (5) extends out of a well;

the compressed gas supply device (8) is connected to the air inlet of the pressure regulating valve (7-6) through a gas pipeline, the two gas path connecting pipes (2-4) are respectively connected with the air outlets of the first pneumatic electromagnetic valve (7-3) and the second pneumatic electromagnetic valve (7-5) through a water pump gas pipe (3), and the air outlet of the wellhead control box (7) is connected to the air extractor (9); the well pumping device also comprises a well pumping pipe (6) communicated with the inside of the downcomer well (1), and the well pumping pipe (6) is connected to an air extractor (9).

2. The active pit dewatering pneumatic drainage system of claim 1, wherein: the shell check valve comprises a fixed valve plate (2-8) with a window in the middle and a movable valve plate (2-9) hinged on the inner side of the window of the fixed valve plate (2-8), a permeable window is arranged on the shell (2-1), the fixed valve plate (2-8) is positioned in the permeable window, the two side edges of the fixed valve plate are welded with the two side edges of the permeable window in a sealing way, and a sealing plate is welded between the upper and lower edges of the fixed valve plate (2-8) and the upper and lower edges of the permeable window in a sealing way; a filter screen (2-5) is also arranged on the water permeable window.

3. The active pit dewatering pneumatic drainage system of claim 2, wherein: an upper hinge (2-10) and a lower hinge (10) are arranged between the fixed valve plate (2-8) and the movable valve plate (2-9), the hinges (2-10) comprise a fixed rotating shaft arranged on the fixed valve plate (2-8) by adopting a shaft seat and a movable rotating shaft arranged on the movable valve plate (2-9) by adopting a shaft seat, and a connecting plate is arranged between the fixed rotating shaft and the movable rotating shaft.

4. The active pit dewatering pneumatic drainage system of claim 3, wherein: the one-way valve (2-6) in the shell comprises a valve body with a valve port at the bottom, the inner cavity of the valve body is communicated with the inner cavity of the drain pipe (2-3), and a one-way diaphragm which only allows seepage to pass upwards is arranged on the valve port.

5. The active pit dewatering pneumatic pumping system of claim 4, wherein: a box body (7-1) of a wellhead control box (7) is provided with a control box air inlet interface (7-7), two air outlet interfaces (7-2) and two air supply interfaces (7-4), the control box air inlet interface (7-7) is connected with an air inlet of a pressure regulating valve (7-6), the two air outlet interfaces (7-2) are respectively connected with air outlets of a first pneumatic electromagnetic valve (7-3) and a second pneumatic electromagnetic valve (7-5), and the two air supply interfaces (7-4) are respectively connected with air outlets of the first pneumatic electromagnetic valve (7-3) and the second pneumatic electromagnetic valve (7-5).

6. The active pit dewatering pneumatic pumping system of claim 5, wherein: an electromagnetic valve is arranged at the connection position of the water pump air pipe (3) and the wellhead control box (7), an electromagnetic valve is arranged on an air path between an air outlet of the wellhead control box (7) and the air extractor (9), and an electromagnetic valve is arranged at the connection position of the wellhead air extraction pipe (6) and the air extractor (9).

7. The active pit dewatering pneumatic drainage system of claim 6, wherein: the compressed air supply device (8) comprises an air source filter, an air compressor and an air storage tank, wherein an outlet of the air source filter is connected to an inlet of the air compressor, and an outlet of the air compressor is connected to an inlet of the air storage tank.