A convertible depth substructure

Abstract

The application discloses a kind of pressure-reducing well structures of convertible pumping depth, it is related to water well technology field, including well pipe, multiple flow-through structures capable of controlling opening and closing are arranged on the well pipe along the axial direction, and the flow-through structure is cut off by inflation expansion water flow, or gas is released to control water flow into well pipe, each flow-through structure is connected with inflation pipeline, the application is by being provided with double-layer flower pipe on the well pipe of pressure-reducing well, and inflation capsule is arranged in double-layer flower pipe and closes or opens the communication of double-layer flower pipe and well pipe, by controlling the expansion and contraction of inflation capsule, the selective plugging of different depth filter water section is realized, so as to realize the conversion pumping function of multilayer pressure-bearing aquifer.

Description

Technical Field

[0001] This invention relates to the field of pressure relief well technology, and specifically to a pressure relief well structure with adjustable pumping depth. Background Technology

[0002] When the bottom of the excavation face of the foundation pit is covered by a confined aquifer, if the water head of the confined aquifer is high, the water pressure may be greater than the weight of the overlying soil, causing a sudden surge failure. Therefore, as the excavation progresses, it is necessary to dewater and depressurize the confined aquifer under the excavation face. At this time, it is necessary to install pumping wells in the confined aquifer.

[0003] In deep foundation pit engineering, multiple confined aquifers with a risk of sudden inrush may exist simultaneously beneath the foundation. If each layer requires depressurization, a dedicated dewatering well must be designed and constructed for each layer, resulting in a large number of depressurization wells within the foundation pit, which is detrimental to earthwork operations and dewatering well management. If the same filter screen is used to penetrate multiple confined layers, hydraulic connections will exist between the aquifers, causing the deeper confined layers to be affected even when only shallow confined water needs to be pumped, increasing the disturbance time of the deeper confined layers. If the diaphragm wall or cutoff wall of the foundation pit does not cut off the deeper confined layers, it will cause a large-scale drop in the water level outside the pit, resulting in groundwater resource loss due to stratum subsidence. Summary of the Invention

[0004] The purpose of this invention is to provide a pressure relief well structure with adjustable pumping depth, which solves the technical problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution: A pressure relief well structure with adjustable pumping depth includes a well casing with multiple controllable flow structures arranged axially on the well casing. The flow structures can cut off the water flow by inflating and expanding with air, or control the water flow into the well casing by releasing gas. Each flow structure is connected to an air-filled pipe.

[0006] As a preferred embodiment of the present invention, the flow structure includes a double-layer perforated pipe disposed on the well casing, and the double-layer perforated pipe is in communication with the interior of the well casing. The interior of the double-layer perforated pipe is filled with an air-filled capsule, and the air-filled pipe is in communication with the interior of the air-filled capsule.

[0007] As a preferred embodiment of the present invention, the double-layer perforated tube includes an outer perforated tube and an inner perforated tube coaxially disposed on the side wall of the well tube, and the inflatable capsule is located between the outer perforated tube and the inner perforated tube.

[0008] As a preferred embodiment of the present invention, the bottom of the inflatable capsule is provided with an elastic strap that connects to the well casing.

[0009] As a preferred embodiment of the present invention, the outer wall of the outer flower tube is covered with a filter protective layer.

[0010] As a preferred embodiment of the present invention, the well pipe is provided with annular arcs on the inner wall facing the double-layer perforated pipe, and the lower annular arc protrudes outward and the upper annular arc is recessed inward.

[0011] As a preferred embodiment of the present invention, an annular groove is provided between the outer and inner perforated tubes on the well pipe, and the opening of the annular groove is connected to the edge of the outwardly protruding annular arc.

[0012] As a preferred embodiment of the present invention, the inner wall of the outer flower tube is provided with a plurality of annular baffles, and each of the annular baffles is inclined downward.

[0013] Compared with the prior art, the present invention has the following advantages: This invention achieves selective blocking of filtration sections at different depths by installing a double-layer perforated pipe on the well casing of a pressure relief well, and by installing an inflatable capsule in the double-layer perforated pipe to seal or open the connection between the double-layer perforated pipe and the well casing. By controlling the expansion and contraction of the inflatable capsule, the invention enables the conversion and pumping function of multiple confined aquifers. Attached Figure Description

[0014] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of a pressure relief well with adjustable pumping depth, provided in an embodiment of the present invention. Figure 2 Provided for embodiments of the present invention Figure 1 An enlarged view of the structure of part A shown in the diagram; Figure 3 A schematic diagram of the flow structure is provided for an embodiment of the present invention.

[0016] The labels in the diagram represent the following: 1. Well casing; 2. Flow structure; 3. Gas filling pipe; 201. Double-layer perforated tube; 202. Inflatable capsule; 203. Outer perforated tube; 204. Inner perforated tube; 205. Elastic pull strap; 206. Filter protective layer; 207. Annular arc; 208. Annular groove; 209. Annular baffle. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] like Figures 1 to 3 As shown, the present invention provides a pressure relief well structure with adjustable pumping depth, including a well pipe 1. Multiple flow structures 2 that can be controlled to open and close are arranged along the axial direction on the well pipe 1. The flow structures 2 can cut off the water flow by inflating and expanding with air, or control the water flow into the well pipe 1 by releasing gas. Each flow structure 2 is connected to an air inflating pipe 3.

[0020] The flow structure 2 includes a double-layer perforated pipe 201 disposed on the well pipe 1, and the double-layer perforated pipe 201 is connected to the inside of the well pipe 1. The inside of the double-layer perforated pipe 201 is filled with an air-filled capsule 202, and the air-filled pipe 3 is connected to the inside of the air-filled capsule 202.

[0021] The double-layer perforated pipe 201 includes an outer perforated pipe 203 and an inner perforated pipe 204 coaxially disposed on the side wall of the well pipe 1, and the air-filled capsule 202 is located between the outer perforated pipe 203 and the inner perforated pipe 204.

[0022] When this application is in use, if it is in a normal state, the inflatable capsule 202 is not filled with gas. The inflatable capsule 202 is small in size and does not affect the flow of groundwater into the well pipe 1 through the double-layer perforated pipe 201.

[0023] When it is necessary to stop pumping water from a confined aquifer at a certain depth, gas is injected into the air-filling pipe 3 through an air-filling device such as an air pump at the wellhead of the water-reducing well. The gas enters the air-filling capsule 202 at the corresponding position, causing the air-filling capsule 202 to expand. The expanded air-filling capsule 202 fills the annular space between the inner perforated pipe 204 and the outer perforated pipe 203, and adheres tightly to the side walls of the inner perforated pipe 204 and the outer perforated pipe 203, blocking the channel for groundwater to flow into the well pipe 1, thereby stopping the flow of groundwater and closing the filter section of that layer.

[0024] When it is necessary to restore the pumping function of this layer, the gas inside the inflatable capsule 202 is released, so that the inflatable capsule 202 returns to the contracted state, and the groundwater can re-enter the well pipe 1.

[0025] By controlling the inflation or deflation state of the inflatable capsules 202 at different depths, pumping switching between different confined aquifers can be achieved, thereby enabling a single well to selectively pump and depressurize multiple aquifers.

[0026] During the prefabrication of the well casing 1, the inflatable capsule 202 is first placed in a predetermined position inside the outer perforated casing 203. Then, the inner perforated casing 204 is installed and welded in place, so that the inflatable capsule 202 is confined in the annular interlayer between the inner perforated casing 204 and the outer perforated casing 203 to form an integral double-layer perforated casing 201.

[0027] The bottom of the inflatable capsule 202 is provided with an elastic strap 205 that connects to the well casing 1.

[0028] After the inflatable capsule 202 releases gas, in order to ensure that the inflatable capsule 202 can retract to the predetermined position after shrinking, the elastic band 205 restricts the inflatable capsule 202 from adhering to the inner flower tube 204 or the outer flower tube 203, so as to avoid affecting the water flow.

[0029] The outer wall of the outer tube 203 is covered with a filter layer 206.

[0030] Used to prevent sand or gravel from entering the double-layered flower tube 201 and to avoid damaging the inflatable capsule 202.

[0031] The inner wall of the well pipe 1 facing the double-layer flower pipe 201 is provided with annular arcs 207, and the lower annular arc 207 protrudes outward, while the upper annular arc 207 is recessed inward.

[0032] That is, there are two annular arcs 207, which are respectively set on the upper and lower sides of the double-layer flower tube 201. The upper annular arc 207 is concave inward and the lower annular arc 207 is convex outward. When the inflatable capsule 202 is inflated and tightly fitted with the two annular arcs 207, the water flow needs to move upward again to contact the inflatable capsule 202, which improves the sealing performance and can further restrict the flow of water.

[0033] An annular groove 208 is provided on the well pipe 1 between the outer perforated pipe 203 and the inner perforated pipe 204, and the groove opening of the annular groove 208 is connected to the edge of the outwardly protruding annular arc 207.

[0034] The annular groove 208 is used to collect gravel or sand that enters the double-layer flower tube 201. The annular groove 208 is connected to the annular arc 207, which can prevent gravel or sand from accumulating at the bottom of the inflatable capsule 202, so as to avoid damage to the inflatable capsule 202 after it is inflated and expands due to contact with gravel or sand.

[0035] Multiple annular baffles 209 are provided on the inner wall of the outer flower tube 203, and each annular baffle 209 is inclined downward.

[0036] The annular baffle 209 restricts the falling of gravel or sand particles into the double-layered perforated pipe 201, so as to make the gravel or sand fall into the annular groove 208 as much as possible.

[0037] In the actual construction process, the construction steps of this application are as follows: Step 1: Drilling The location of the depressurization well is determined according to the dewatering design requirements of the foundation pit project. Drilling is carried out using rotary drilling rigs, reverse circulation drilling rigs, or impact drilling rigs to ensure that the drilling depth penetrates through each confined aquifer that requires depressurization treatment.

[0038] Step 2, Prefabrication of Well Casing 1 The well casing 1 structure is prefabricated in the factory, and a double-layer perforated casing 201 structure is installed at the location corresponding to the confined aquifer. During the prefabrication process, the outer perforated casing 203 is installed first, and the inflatable capsule 202 is placed in a predetermined position inside the outer perforated casing 203. At the same time, the inflatable pipe 3 is laid along the inside of the well casing to the wellhead. Subsequently, the inner perforated casing 204 is installed and welded to fix it, so that the inflatable capsule 202 is located in the annular space between the inner perforated casing 204 and the outer perforated casing 203.

[0039] Step 3, Lowering Well Casing 1 The prefabricated well pipe 1 is hoisted and lowered into the borehole as a whole, and the position of the well pipe 1 is adjusted so that the double-layer perforated pipe 201 structure matches the position of the corresponding confined aquifer.

[0040] Step 4: Filter media filling A gravel or medium-coarse sand filter layer is filled between the outer wall of well casing 1 and the borehole wall to improve the efficiency of groundwater entering well casing 1; in non-filtering sections, clay or cement grout can be used for sealing to prevent hydraulic connection between different aquifers.

[0041] Step 5: Installation of wellhead control device An inflation control device, including an inflation pump, a pressure gauge, and control valves, is installed at the wellhead to control the inflation and deflation of each inflation capsule 202.

[0042] Step 6: Installation of pumping equipment A submersible pump and pumping pipeline are installed inside well 1, and a drainage system and power supply are connected.

[0043] Step 7: System Debugging and Operation By controlling the inflation or deflation of the inflatable capsule 202, the opening or closing of different depth filtration sections can be achieved, thereby completing the pumping conversion between different confined aquifers.

[0044] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention. This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A pressure relief well structure with adjustable pumping depth, characterized in that, The well pipe (1) is provided with a plurality of flow structures (2) that can be controlled to open and close along the axial direction. The flow structures (2) cut off the water flow by inflating and expanding, or release gas to control the water flow into the well pipe (1). Each flow structure (2) is connected to an air-filled pipe (3).

2. The pressure relief well structure with adjustable pumping depth according to claim 1, characterized in that, The flow structure (2) includes a double-layer perforated pipe (201) disposed on the well pipe (1), and the double-layer perforated pipe (201) is connected to the inside of the well pipe (1). The inside of the double-layer perforated pipe (201) is filled with an air-filled capsule (202), and the air-filled pipe (3) is connected to the inside of the air-filled capsule (202).

3. The pressure relief well structure with convertible pumping depth according to claim 2, characterized in that, The double-layer perforated tube (201) includes an outer perforated tube (203) and an inner perforated tube (204) coaxially disposed on the side wall of the well tube (1), and the inflatable capsule (202) is located between the outer perforated tube (203) and the inner perforated tube (204).

4. The pressure relief well structure with adjustable pumping depth according to claim 3, characterized in that, The bottom of the inflatable capsule (202) is provided with an elastic strap (205) that is connected to the well pipe (1).

5. The pressure relief well structure with convertible pumping depth according to claim 3, characterized in that, The outer wall of the outer flower tube (203) is covered with a filter protective layer (206).

6. The pressure relief well structure with adjustable pumping depth according to claim 3, characterized in that, The well pipe (1) has an annular arc (207) on the inner wall facing the double-layer flower pipe (201), and the lower annular arc (207) protrudes outward, while the upper annular arc (207) is recessed inward.

7. The pressure relief well structure with convertible pumping depth according to claim 6, characterized in that, An annular groove (208) is provided between the outer perforated tube (203) and the inner perforated tube (204) on the well tube (1), and the groove of the annular groove (208) is connected to the edge of the outwardly protruding annular arc (207).

8. The pressure relief well structure with convertible pumping depth according to claim 3, characterized in that, The inner wall of the outer flower tube (203) is provided with a plurality of annular baffles (209), and each of the annular baffles (209) is inclined downward.

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