Constant-pressure perturbation sampling equipment and method for underground water in strong-permeability stratum

Abstract

The invention discloses a constant-pressure perturbation sampling device and method for underground water in a strong-permeability stratum, and relates to the technical field of underground water collection. Comprising a sampling well, a positioning bracket arranged at the upper end of the sampling well, and a constant-pressure perturbation sampling unit arranged on the positioning bracket, the external sleeve extends into the sampling well to collect and preliminarily temporarily store underground water, the winding rope is used for driving the collecting inner cylinder to move into the external sleeve through the through opening, the collecting inner cylinder is used for secondarily collecting an underground water sample in the external sleeve, and the collecting inner cylinder is limited in the external sleeve, so that the underground water sample in the external sleeve can be collected. The device can be ensured to be put down or recycled directly inside the external sleeve, large-range water flow disturbance caused by direct contact with underground water is avoided, the accuracy of subsequent detection is improved, an arc-shaped rotating plate and an elastic valve clack are further arranged outside the external sleeve to form an isolation buffer layer, original water chemical characteristics are reserved, and the service life of the device is prolonged. And direct interference of subsequent sampling operation to the stratum is avoided.

Description

Technical Field

[0001] This invention relates to the field of groundwater sampling technology, specifically to a constant-pressure micro-disturbance sampling device and method for groundwater in highly permeable strata. Background Technology

[0002] Groundwater is an important component of water resources. Due to its stable quantity and good quality, it is widely used as an important water source for agricultural irrigation, mining, and cities. In order to promote environmental protection and sustainable development, groundwater testing is usually required. Groundwater sampling helps improve the accuracy and time resolution of environmental monitoring and helps to understand the quality and pollution level of groundwater resources in a timely manner.

[0003] Sampling and testing groundwater is one of the effective ways to directly reflect the local water pollution status. When sampling and testing multiple layers of groundwater, how to prevent mutual interference between the multiple layers of groundwater has a direct impact on the accuracy of water testing. Therefore, there is an urgent need for a groundwater sampling device.

[0004] When existing groundwater sampling equipment is in use, the sampling equipment is often in direct contact with groundwater or moves freely in the well without protection. In this case, the groundwater will be directly disturbed during the lowering, retrieval or collection process, making it difficult to reflect the true state of the groundwater in the formation during subsequent testing, reducing accuracy. Without a physical barrier that adheres to the well wall, it is impossible to form a separation between the sampling area and the formation. The disturbance generated by the sampling operation can easily spread directly to the entire well and even the formation. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a constant-pressure micro-disturbance sampling device and method for groundwater in highly permeable formations.

[0006] The technical solution of the present invention: a constant pressure micro-disturbance sampling device for groundwater in highly permeable formations, comprising a sampling well, a positioning bracket disposed at the upper end of the sampling well, and a constant pressure micro-disturbance sampling unit disposed on the positioning bracket;

[0007] The positioning bracket includes two mounting vertical brackets with threaded vertical rods distributed on opposite sides, a mounting horizontal plate whose side wall is threadedly connected to the threaded vertical rods through mounting sleeves and has a through opening at the center of its upper end, and a mounting bracket located on the positioning bracket and directly above the through opening. The threaded vertical rods are driven to rotate by a first rotary motor.

[0008] The constant pressure micro-perturbation sampling unit includes an outer sleeve located at the bottom of the mounting plate and having a first solenoid valve on its outer wall, a winding roller located on the mounting bracket and driven by a second rotary motor, and an inner collection cylinder connected to the winding roller by a winding rope and having a gravity sensor at the connection point.

[0009] The bottom of the inner cylinder is equipped with a second solenoid valve. The inner diameter of the inner cylinder is smaller than the inner diameter of the outer sleeve. The outer wall of the outer sleeve is equipped with two symmetrically distributed support rods. An arc-shaped rotating plate is hinged on the support rod. The arc-shaped rotating plate is driven to rotate by a third rotary motor. Each arc-shaped rotating plate is evenly provided with several through holes, and each of the above locations is provided with several elastic valve flaps that converge with each other.

[0010] Furthermore, the bottom end of the winding rope is connected to a connecting disc, and the outer wall of the connecting disc is provided with several fixing clamping rings along the circumference. There are multiple collection inner cylinders, and each collection inner cylinder corresponds to one of the fixing clamping rings.

[0011] Note: When collecting groundwater samples, the corresponding inner collection cylinder is simultaneously clamped by the various fixed clamping rings on the outer wall of the connecting plate. Several groundwater samples can be collected at the same time, requiring only one lowering. This results in less disturbance to the water body in the sampling well and more accurately reflects the original state of the groundwater.

[0012] Furthermore, the fixing clamping ring includes an arc-shaped fixing ring and an arc-shaped adjusting ring connected to the arc-shaped fixing ring via a buffer spring. The inner walls of both the arc-shaped fixing ring and the arc-shaped adjusting ring are provided with anti-slip pads.

[0013] Explanation: The arc-shaped fixing ring is the basic load-bearing structure of the fixed clamping ring, providing a stable support frame for the entire clamping component. The buffer spring has good elasticity and extensibility. When facing collection inner cylinders with different outer diameters, it can drive the arc-shaped adjusting ring to adjust its position through its own expansion and contraction. This allows the fixed clamping ring to adapt to collection inner cylinders of various specifications, greatly improving the equipment's adaptability to different sampling needs. The arc-shaped adjusting ring is in direct contact with the collection inner cylinder, and the anti-slip pad on its inner wall increases the friction between it and the outer wall of the collection inner cylinder, effectively preventing the collection inner cylinder from sliding or rotating within the fixed clamping ring. This ensures that the collection inner cylinder remains stable during lifting and sampling, avoiding any impact on sampling accuracy due to shaking.

[0014] Furthermore, the left and right sides of the inner wall of the mounting bracket are respectively connected to symmetrically placed stabilizing clamping blocks by horizontally placed first hydraulic rods. The opposite sides of the two stabilizing clamping blocks are respectively provided with clamping grooves that match the shape of the connecting plate. The clamping grooves are provided with sub-clamping grooves that match the fixed clamping ring.

[0015] Explanation: After groundwater samples are collected from each inner collection cylinder, the second rotary motor drives the winding roller to rotate in the opposite direction, thereby synchronously moving the connecting plate and the inner collection cylinder into the mounting bracket. When the two sides of the connecting plate are aligned with the stabilizing clamping blocks, the first hydraulic rod pushes the stabilizing clamping blocks to move horizontally and move closer to each other. The clamping groove can perfectly fit with the outer wall of the connecting plate, limiting the overall position of the connecting plate. The matching design of the sub-clamping groove and the fixed clamping ring can form a targeted fixation of the fixed clamping ring, further enhancing the stability of the connecting plate and the inner collection cylinder assembly. This effectively avoids positional displacement caused by shaking during the lowering or lifting of the inner collection cylinder, ensuring the stability and accuracy of the sampling operation.

[0016] Furthermore, the bottom of the collecting inner cylinder is an open structure, and a movable adjustment frame is connected to the center of the bottom of the connecting plate via an electric telescopic rod. The movable adjustment frame includes a central linkage block connected to the electric telescopic rod, horizontal connecting support rods distributed circumferentially and corresponding one-to-one with the collecting inner cylinder, and a sealing cover provided on each of the horizontal connecting support rods and capable of being fastened to the bottom of each collecting inner cylinder. The inner wall of the sealing cover is provided with a sealing ring.

[0017] Explanation: When groundwater samples need to be collected, the groundwater entering the outer casing passes through each of the second solenoid valves into the corresponding collection inner cylinder. At this time, each sealing cover seals the bottom of the corresponding collection inner cylinder, thereby storing the collected groundwater samples. When transferring the groundwater samples collected in each collection inner cylinder, the extension action of the electric telescopic rod separates each sealing cover from the bottom of the corresponding collection inner cylinder, thereby allowing the groundwater samples to flow out from the bottom of the collection inner cylinder. This method balances the stability of groundwater sample storage, the convenience of transfer, and the integrity of the samples, while also improving operational efficiency and making it more suitable for groundwater sample collection.

[0018] Furthermore, there are multiple first solenoid valves, which are distributed circumferentially at the bottom end of the outer sleeve sidewall, and the outer sleeve sidewall is provided with an annular filter screen that can cover each of the first solenoid valves.

[0019] Explanation: Each first solenoid valve is distributed circumferentially at the bottom of the side wall of the outer casing, allowing groundwater to enter the outer casing evenly from different directions. This avoids excessive local water flow disturbance caused by a single inlet, better achieving the sampling requirements of constant pressure and micro-disturbance, and ensuring the stability of the sampling environment. The annular filter screen covers each first solenoid valve, which can pre-filter the groundwater entering the outer casing, effectively blocking impurities such as silt and gravel in the water. This prevents impurities from entering the first solenoid valve and causing valve blockage or damage, extending the service life of the first solenoid valve. At the same time, it also avoids impurities from contaminating subsequent groundwater samples, ensuring the purity of the samples.

[0020] Furthermore, a clamping plate is connected to the center of the bottom end of the outer sleeve via a vertically installed second hydraulic rod. The bottom end of the clamping plate is provided with several insertion spikes. A sealing strip is movably connected to the outer arc sidewall of the arc-shaped rotating plate. The sealing strip is made of elastic material.

[0021] Explanation: The second hydraulic rod can push the clamping plate downwards. The insertion spikes at the bottom of the clamping plate can be inserted into the soil, thereby firmly fixing the bottom of the outer casing at the designated sampling position. This effectively prevents the outer casing from shifting or tilting due to water flow impact or other external forces during sampling, enhancing the overall stability of the equipment. When the arc-shaped rotating plate rotates to contact the well wall of the sampling well, the elastic sealing strip can tightly fit the contact surface through its own elastic deformation, filling the gap between the arc-shaped rotating plate and the contact surface, achieving a good sealing effect. This effectively prevents groundwater from non-target areas from entering the sampling area, avoiding interference with the sample and ensuring the accuracy of the sampling.

[0022] Furthermore, each of the mounting bracket sidewalls is provided with a retractable diagonal brace, one end of which is hinged to the mounting bracket sidewall, and the other end is provided with a support seat with anti-slip texture. The diagonal brace is provided with a locking bolt for locking its extension length.

[0023] Description: The telescopic diagonal brace can flexibly adjust its length according to the actual installation of the positioning bracket and the terrain conditions around the sampling well. By placing the support base at the other end of the diagonal brace in a suitable position on the ground and locking its telescopic length with locking bolts, the diagonal brace can provide stable support for the installation frame from the side. Together with the installation frame, it forms a stable triangular support structure, which greatly improves the overall anti-tipping ability and stability of the positioning bracket.

[0024] This invention also discloses a constant-pressure perturbation sampling method for groundwater in highly permeable formations, based on the aforementioned constant-pressure perturbation sampling device for groundwater in highly permeable formations, comprising the following steps:

[0025] S1. When collecting groundwater samples, the first rotary motor drives the threaded vertical rod to rotate, causing the installation sleeve to move downward along the threaded vertical rod, while the installation horizontal plate also moves downward synchronously until the outer sleeve moves into the sampling well.

[0026] S2. Drive the winding roller to rotate in the forward direction by the second rotary motor, so that the winding rope drives the inner collection cylinder to move through the through-hole into the outer sleeve;

[0027] S3. The corresponding arc-shaped rotating plate is driven to rotate by the third rotary motor until the two arc-shaped rotating plates rotate to the horizontal direction and contact the well wall of the sampling well;

[0028] S4. Open the first solenoid valve and the second solenoid valve. At this time, the groundwater enters the outer casing through the first solenoid valve and enters the inner collection cylinder through the second solenoid valve, thus completing the collection of groundwater samples.

[0029] S5. After the collection is completed, the second rotary motor drives the winding roller to rotate in the opposite direction, and the inner cylinder of the collection is pulled out from the outer sleeve by the winding rope and discharged through the second solenoid valve.

[0030] The beneficial effects of this invention are:

[0031] The high-permeability groundwater constant-pressure micro-disturbance sampling device of the present invention collects and temporarily stores groundwater by extending an external casing into the sampling well. A winding rope then moves the inner sampling cylinder through the penetration port into the outer casing, where a secondary sampling of the groundwater sample is performed. By confining the inner sampling cylinder within the outer casing, it is ensured that its lowering or retrieval is carried out directly within the outer casing, avoiding direct contact with groundwater and thus preventing large-scale water flow disturbance, thereby improving the accuracy of subsequent detection. Furthermore, an arc-shaped rotating plate and an elastic valve flap are installed on the outside of the outer casing to form an "isolation buffer layer." The arc-shaped rotating plate adheres to the well wall to form a physical barrier, and the elastic valve flap only allows groundwater to flow smoothly into the casing in one direction (blocking reverse disturbance). This ensures that the water temporarily stored in the casing forms a "weak coupling" with the original formation water flow, preserving the original water chemical characteristics while preventing direct interference with the formation during subsequent sampling operations. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0033] Figure 2 This is a main view of the inner collecting cylinder of the present invention being installed on the connecting plate;

[0034] Figure 3 This is a top view of the inner collecting cylinder of the present invention installed on the connecting plate;

[0035] Figure 4 This is a top view of the arc-shaped rotating plate of the present invention mounted on the outer sleeve;

[0036] Figure 5 This is the invention Figure 1 Enlarged view of point A in the image;

[0037] Figure 6 This is a top view of the installation of the stabilizing clamping block and the mounting bracket of the present invention;

[0038] Figure 7 This is a top view of the movable adjustment frame of the present invention.

[0039] Among them, 1-sampling well, 2-positioning bracket, 20-through port, 21-threaded vertical rod, 210-first rotary motor, 22-mounting vertical frame, 220-diagonal brace, 221-support base, 23-mounting horizontal plate, 230-mounting sleeve, 24-mounting bracket, 240-first hydraulic rod, 241-stabilizing clamping block, 242-clamping groove, 243-sub-clamping groove, 3-constant pressure micro-perturbation sampling unit, 30-first solenoid valve, 31-outer sleeve, 310-support rod, 311-arc rotating plate, 312-third rotary motor, 313-through hole, 314-elastic valve disc. 315-Sealing strip, 33-Winding roller, 330-Second rotary motor, 34-Collection inner cylinder, 340-Gravity sensor, 341-Second solenoid valve, 35-Connecting disc, 350-Fixing clamping ring, 351-Arc-shaped fixing ring, 352-Buffer spring, 353-Arc-shaped adjusting ring, 354-Anti-slip pad, 355-Electric telescopic rod, 356-Moving adjusting frame, 357-Central linkage block, 358-Horizontal connecting support rod, 359-Sealing cover, 3590-Sealing ring, 36-Annular filter screen, 37-Pressure plate, 370-Second hydraulic rod, 371-Insertion spike. Detailed Implementation

[0040] Example 1

[0041] like Figure 1 As shown, a constant pressure perturbation sampling device for groundwater in highly permeable formations includes a sampling well 1, a positioning bracket 2 located at the upper end of the sampling well 1, and a constant pressure perturbation sampling unit 3 located on the positioning bracket 2.

[0042] The positioning bracket 2 includes two mounting brackets 22 with threaded vertical rods 21 distributed on opposite sides, a mounting horizontal plate 23 whose side wall is threadedly connected to the threaded vertical rods 21 through mounting sleeves 230 and has a through opening 20 at the center of its upper end, and a mounting bracket 24 located on the positioning bracket 2 and directly above the through opening 20. The threaded vertical rods 21 are driven to rotate by a first rotary motor 210. The first rotary motor 210 can adopt existing technology, such as a motor of model Y90S-4.

[0043] The constant pressure perturbation sampling unit 3 includes an outer sleeve 31 located at the bottom of the mounting plate 23 and with a first solenoid valve 30 on its outer wall, a winding roller 33 located on the mounting bracket 24 and driven by a second rotary motor 330, and an inner collection cylinder 34 connected to the winding roller 33 by a winding rope and with a gravity sensor 340 at the connection point. The first solenoid valve 30, the second rotary motor 330 and the gravity sensor 340 all adopt existing technologies. For example, the first solenoid valve 30 can be a solenoid valve of model 2W-160-15, the second rotary motor 330 can be a motor of model Y90S-4, and the gravity sensor 340 can be a gravity sensor of model YZC-131.

[0044] like Figure 4 , 5 As shown, a second solenoid valve 341 is provided at the bottom of the inner cylinder 34. The inner diameter of the inner cylinder 34 is 2 / 3 of the inner diameter of the outer sleeve 31. Two symmetrically distributed support rods 310 are provided on the outer wall of the outer sleeve 31. An arc-shaped rotating plate 311 is hinged on the support rod 310. The arc-shaped rotating plate 311 is driven to rotate by a third rotary motor 312. Each arc-shaped rotating plate 311 is evenly provided with 7 through holes 313. Each hole is provided with 4 elastic valve discs 314 that converge with each other. The second solenoid valve 341 and the third rotary motor 312 both adopt existing technologies. For example, the second solenoid valve 341 can be a solenoid valve of model 2W-160-15, and the third rotary motor 312 can be a motor of model Y90S-4.

[0045] Example 2

[0046] This embodiment discloses a constant-pressure perturbation sampling method for groundwater in highly permeable formations, based on a constant-pressure perturbation sampling device for groundwater in highly permeable formations in Embodiment 1, including the following steps:

[0047] S1. When collecting groundwater samples, the first rotary motor 210 drives the threaded vertical rod 21 to rotate, causing the mounting sleeve 230 to move downward along the threaded vertical rod 21, and the mounting horizontal plate 23 will also move downward synchronously until the outer sleeve 31 moves down into the sampling well 1.

[0048] S2. The second rotary motor 330 drives the winding roller 33 to rotate in the forward direction, so that the winding rope drives the inner collection cylinder 34 to move through the through-hole 20 into the outer sleeve 31.

[0049] S3. The third rotary motor 312 drives the corresponding arc-shaped rotating plate 311 to rotate until the two arc-shaped rotating plates 311 rotate to the horizontal direction and contact the well wall of the sampling well 1, which can effectively prevent groundwater from non-target areas from entering the sampling area.

[0050] S4. Open the first solenoid valve 30 and the second solenoid valve 341. At this time, groundwater enters the outer casing 31 through the first solenoid valve 30 and enters the collection inner cylinder 34 through the second solenoid valve 341, thus completing the collection of groundwater samples.

[0051] S5. After the collection is completed, the second rotary motor 330 drives the winding roller 33 to rotate in the opposite direction, and the inner collection cylinder 34 is pulled out from the outer sleeve 31 by the winding rope and discharged through the second solenoid valve 341.

[0052] Example 3

[0053] The difference between this embodiment and Embodiment 1 is that:

[0054] The bottom end of the winding rope is connected to a connecting plate 35. The outer wall of the connecting plate 35 is provided with 6 fixed clamping rings 350 along the circumference. There are 6 collection inner cylinders 34. The 6 collection inner cylinders 34 correspond one-to-one with each fixed clamping ring 350. The corresponding collection inner cylinders 34 are clamped simultaneously by each fixed clamping ring 350 on the outer wall of the connecting plate 35. Several groundwater samples can be collected at the same time. Only one lowering is required. It causes less disturbance to the water body in the sampling well 1 and can more realistically reflect the original state of the groundwater.

[0055] like Figure 3 As shown, the fixed clamping ring 350 includes an arc-shaped fixed ring 351 and an arc-shaped adjusting ring 353 connected to the arc-shaped fixed ring 351 via a buffer spring 352. Both the arc-shaped fixed ring 351 and the arc-shaped adjusting ring 353 have anti-slip pads 354 on their inner walls. The arc-shaped fixed ring 351 is the basic load-bearing structure of the fixed clamping ring 350, providing a stable support frame for the entire clamping component. The buffer spring 352 has good elasticity and flexibility; when facing collection inner cylinders 34 with different outer diameters, it can adjust the position of the arc-shaped adjusting ring 353 through its own expansion and contraction. This allows the fixed clamping ring 350 to be adapted to various sizes of the collection inner cylinder 34, greatly improving the equipment's adaptability to different sampling needs. The arc-shaped adjusting ring 353 is in direct contact with the collection inner cylinder 34, and the anti-slip pad 354 on its inner wall can increase the friction between it and the outer wall of the collection inner cylinder 34, effectively preventing the collection inner cylinder 34 from sliding or rotating within the fixed clamping ring 350. This ensures that the collection inner cylinder 34 remains stable during lifting and sampling, avoiding the impact of shaking on sampling accuracy. The anti-slip pad 354 is made of EPDM rubber.

[0056] like Figure 1 , 6 As shown, the left and right sides of the inner wall of the mounting bracket 24 are respectively connected to symmetrically placed stabilizing clamping blocks 241 by horizontally placed first hydraulic rods 240. The opposite sides of the two stabilizing clamping blocks 241 are respectively provided with clamping grooves 242 that match the shape of the connecting plate 35. The clamping grooves 242 are provided with sub-clamping grooves 243 that match the fixed clamping ring 350, which limit the position of the connecting plate 35 as a whole. The matching design of the sub-clamping grooves 243 and the fixed clamping ring 350 can form a targeted fixation of the fixed clamping ring 350, further enhancing the stability of the assembly of the connecting plate 35 and the collection inner cylinder 34, effectively avoiding positional displacement caused by shaking during the lowering or lifting of the collection inner cylinder 34, and ensuring the stability and accuracy of the sampling operation. The first hydraulic rod 240 adopts existing technology, such as a piston hydraulic rod of model MOB40×100.

[0057] like Figure 2 , 7As shown, the bottom of the collection inner cylinder 34 is open, and a movable adjustment frame 356 is connected to the center of the bottom of the connecting plate 35 via an electric telescopic rod 355. The movable adjustment frame 356 includes a central linkage block 357 connected to the electric telescopic rod 355, horizontal connecting support rods 358 distributed circumferentially and corresponding one-to-one with the collection inner cylinder 34, and sealing covers 359 provided on each horizontal connecting support rod 358 and capable of being fastened to the bottom of each collection inner cylinder 34. The inner wall of the sealing cover 359 is provided with a sealing ring 3590. When transferring the groundwater samples collected from each collection inner cylinder 34... The electric telescopic rod 355 extends to separate each sealing cover 359 from the bottom of the corresponding collection inner cylinder 34, allowing the groundwater sample to flow out from the bottom of the collection inner cylinder 34. This balances the stability of groundwater sample storage, the convenience of transfer, and the integrity of the sample, while also improving operational efficiency and making it more suitable for groundwater sample collection. Both the electric telescopic rod 355 and the sealing ring 3590 use existing technologies. For example, the electric telescopic rod 355 can be a model XTL100-150 electric telescopic rod, and the sealing ring 3590 is made of polytetrafluoroethylene.

[0058] Example 4

[0059] The difference between this embodiment and Embodiment 2 is that:

[0060] In step S2, the corresponding collection inner cylinder 34 is simultaneously clamped by the fixed clamping rings 350 on the outer wall of the connecting plate 35. The second rotary motor 330 drives the winding roller 33 to rotate in the forward direction, so that the winding rope drives the connecting plate 35 to move through the through hole 20 into the outer sleeve 31. Several groundwater samples can be collected at the same time. Only one lowering is required, and the disturbance to the water in the sampling well 1 is smaller. When facing collection inner cylinders 34 with different outer diameters, the position can be adjusted by the arc-shaped adjustment ring 353 through its own expansion and contraction deformation, so that the fixed clamping ring 350 can be adapted to collection inner cylinders 34 of various specifications.

[0061] In step S5, after the groundwater samples are collected in each inner collection cylinder 34, the second rotary motor 330 drives the winding roller 33 to rotate in the opposite direction, thereby moving the connecting plate 35 and the inner collection cylinder 34 synchronously upward into the mounting bracket 24. When the two sides of the connecting plate 35 are directly opposite the stabilizing clamping block 241, the first hydraulic rod 240 pushes the stabilizing clamping block 241 to move horizontally and move closer to each other. The clamping groove 242 can perfectly fit with the outer wall of the connecting plate 35, limiting the connecting plate 35 as a whole. The matching design of the sub-clamping groove 243 and the fixed clamping ring 350 can form a targeted fixation of the fixed clamping ring 350.

[0062] In step S5, when transferring the groundwater samples collected in each collection inner cylinder 34, the extension action of the electric telescopic rod 355 causes each sealing cover 359 to separate from the bottom end of the corresponding collection inner cylinder 34, thereby allowing the groundwater samples to flow out from the bottom end of the collection inner cylinder 34.

[0063] Example 5

[0064] The difference between this embodiment and embodiment 3 is that:

[0065] There are four first solenoid valves 30, which are circumferentially distributed at the bottom of the side wall of the outer sleeve 31. The side wall of the outer sleeve 31 is equipped with an annular filter screen 36 that encloses each of the first solenoid valves 30. The circumferential distribution of the first solenoid valves 30 at the bottom of the side wall of the outer sleeve 31 allows groundwater to enter the outer sleeve 31 evenly from different directions, avoiding excessive local water flow disturbance caused by a single inlet. This better achieves the sampling requirements of constant pressure and minimal disturbance, ensuring the stability of the sampling environment. The annular filter screen 36 encloses each of the first solenoid valves 30. The groundwater entering the outer casing 31 can be pre-filtered to effectively block impurities such as mud, sand and gravel in the water, preventing impurities from entering the first solenoid valve 30 and causing valve blockage or damage, thus extending the service life of the first solenoid valve 30. At the same time, it also avoids impurities from contaminating subsequent groundwater samples and ensures the purity of the samples. The first solenoid valve 30 and the annular filter screen 36 both adopt existing technologies. For example, the first solenoid valve 30 can be a solenoid valve with the model number 2W-160-15, and the annular filter screen 36 can be an existing stainless steel annular mesh.

[0066] like Figure 1As shown, a clamping plate 37 is connected to the center of the bottom end of the outer sleeve 31 via a vertically installed second hydraulic rod 370. The bottom end of the clamping plate 37 has several insertion spikes 371. A sealing strip 315 is movably connected to the outer arc sidewall of the arc-shaped rotating plate 311. The second hydraulic rod 370 can push the clamping plate 37 downwards, allowing the insertion spikes 371 at the bottom of the clamping plate 37 to insert into the soil, thus firmly fixing the bottom end of the outer sleeve 31 at the designated sampling position. This effectively prevents the outer sleeve 31 from shifting or tilting during sampling due to water flow impact or other external forces, enhancing the overall stability of the equipment. When the rotating plate 311 rotates to contact the well wall of sampling well 1, the elastic sealing strip 315 can tightly fit the contact surface through its own elastic deformation, filling the gap between the arc-shaped rotating plate 311 and the contact surface, thus playing a good sealing role. This can effectively prevent groundwater from non-target areas from entering the sampling area, avoid interfering with the sampling sample, and ensure the accuracy of sampling. The second hydraulic rod 370 adopts existing technology, such as a piston-type hydraulic rod of model MOB40×100. The sealing strip 315 is made of elastic material, such as nitrile rubber, TPE, or TPV.

[0067] Each mounting frame 22 has a telescopic diagonal brace 220 on its side wall. One end of the diagonal brace 220 is hinged to the side wall of the mounting frame 22, and the other end is provided with a support seat 221 with anti-slip texture. The diagonal brace 220 is provided with a locking bolt for locking its telescopic length. The telescopic diagonal brace 220 can flexibly adjust its length according to the actual installation of the positioning bracket 2 and the terrain conditions around the sampling well. By placing the support seat 221 at the other end of the diagonal brace 220 in a suitable position on the ground and locking its telescopic length with the locking bolt, the diagonal brace 220 can provide stable support for the mounting frame 22 from the side. Together with the mounting frame 22, it forms a stable triangular support structure, which greatly improves the overall anti-tipping ability and stability of the positioning bracket 2.

[0068] Example 6

[0069] The difference between this embodiment and embodiment 4 is that:

[0070] In step S4, each of the first solenoid valves 30 is distributed circumferentially at the bottom of the side wall of the outer sleeve 31, which allows groundwater to enter the interior of the outer sleeve 31 evenly from different directions. The annular filter screen 36 covers each of the first solenoid valves 30, which can pre-filter the groundwater entering the outer sleeve 31 and effectively block impurities such as mud, sand and gravel in the water.

[0071] In step S1, after the outer sleeve 31 is lowered into the sampling well 1, the second hydraulic rod 370 can push the clamping plate 37 to move downward, and the insertion spike 371 at the bottom of the clamping plate 37 can be inserted into the soil, thereby firmly fixing the bottom of the outer sleeve 31 at the designated sampling position.

[0072] In step S3, when the arc-shaped rotating plate 311 rotates to contact the well wall of the sampling well 1, the elastic sealing strip 315 can tightly fit the contact surface through its own elastic deformation, filling the gap between the arc-shaped rotating plate 311 and the contact surface, thus playing a good sealing role.

Claims

1. A constant-pressure micro-disturbance sampling device for groundwater in highly permeable formations, characterized in that, It includes a sampling well (1), a positioning bracket (2) located at the upper end of the sampling well (1), and a constant pressure micro-perturbation sampling unit (3) located on the positioning bracket (2); The positioning bracket (2) includes two mounting brackets (22) with threaded vertical rods (21) distributed on opposite sides, a mounting horizontal plate (23) whose side wall is threadedly connected to the threaded vertical rods (21) through mounting sleeves (230) and has a through hole (20) at the center of its upper end, and a mounting bracket (24) located on the positioning bracket (2) and directly above the through hole (20). The threaded vertical rods (21) are driven to rotate by a first rotary motor (210). The constant pressure perturbation sampling unit (3) includes an outer sleeve (31) located at the bottom of the mounting plate (23) and with a first solenoid valve (30) on its outer wall, a winding roller (33) located on the mounting bracket (24) and driven by a second rotary motor (330), and a collection inner cylinder (34) connected to the winding roller (33) by a winding rope and with a gravity sensor (340) at the connection point; The bottom end of the collecting inner cylinder (34) is provided with a second solenoid valve (341). The inner diameter of the collecting inner cylinder (34) is smaller than the inner diameter of the outer sleeve (31). The outer wall of the outer sleeve (31) is provided with two symmetrically distributed support rods (310). An arc-shaped rotating plate (311) is hinged on the support rod (310). The arc-shaped rotating plate (311) is driven to rotate by a third rotary motor (312). Several through holes (313) are evenly provided on each arc-shaped rotating plate (311). Several elastic valve discs (314) that converge with each other are provided at each location.

2. The high-permeability groundwater constant-pressure micro-disturbance sampling device according to claim 1, characterized in that, The bottom end of the winding rope is connected to a connecting disc (35). The outer wall of the connecting disc (35) is provided with several fixing clamping rings (350) along the circumference. There are multiple collection inner cylinders (34), and each collection inner cylinder (34) corresponds to one of the fixing clamping rings (350).

3. The high-permeability groundwater constant-pressure micro-disturbance sampling device according to claim 2, characterized in that, The fixed clamping ring (350) includes an arc-shaped fixed ring (351) and an arc-shaped adjusting ring (353) connected to the arc-shaped fixed ring (351) by a buffer spring (352). The inner walls of the arc-shaped fixed ring (351) and the arc-shaped adjusting ring (353) are provided with anti-slip pads (354).

4. The high-permeability groundwater constant-pressure micro-disturbance sampling device according to claim 2, characterized in that, The mounting bracket (24) has symmetrically placed stabilizing clamping blocks (241) on its inner wall on both the left and right sides via a horizontally placed first hydraulic rod (240). The two stabilizing clamping blocks (241) have clamping grooves (242) that match the shape of the connecting plate (35) on their opposite sides. The clamping grooves (242) have sub-clamping grooves (243) that match the fixed clamping ring (350).

5. The high-permeability groundwater constant pressure micro-disturbance sampling device according to claim 2, characterized in that, The bottom of the collection inner cylinder (34) is open, and a movable adjustment frame (356) is connected to the center of the bottom of the connecting plate (35) via an electric telescopic rod (355). The movable adjustment frame (356) includes a central linkage block (357) connected to the electric telescopic rod (355), horizontal connecting support rods (358) distributed circumferentially and corresponding one-to-one with the collection inner cylinder (34), and a sealing cover (359) provided on each of the horizontal connecting support rods (358) and capable of being fastened to the bottom of each collection inner cylinder (34). The inner wall of the sealing cover (359) is provided with a sealing ring (3590).

6. The constant pressure micro-disturbance sampling device for highly permeable groundwater according to claim 1, characterized in that, There are multiple first solenoid valves (30), and the multiple first solenoid valves (30) are distributed circumferentially at the bottom end of the side wall of the outer sleeve (31), and the side wall of the outer sleeve (31) is provided with an annular filter screen (36) that can cover each first solenoid valve (30).

7. The high-permeability groundwater constant-pressure micro-disturbance sampling device according to claim 1, characterized in that, At the center of the bottom end of the outer sleeve (31), a pressure plate (37) is connected by a vertically installed second hydraulic rod (370). The bottom end of the pressure plate (37) is provided with several insertion spikes (371). A sealing strip (315) is movably connected to the outer arc sidewall of the arc rotating plate (311). The sealing strip (315) is made of elastic material.

8. The constant pressure micro-disturbance sampling device for highly permeable groundwater as described in claim 1, characterized in that, Each of the mounting brackets (22) has a telescopic diagonal brace (220) on its side wall. One end of the diagonal brace (220) is hinged to the side wall of the mounting bracket (22), and the other end is provided with a support seat (221) with anti-slip texture. The diagonal brace (220) is provided with a locking bolt for locking its telescopic length.

9. A constant-pressure micro-disturbance sampling method for groundwater in highly permeable formations, based on the constant-pressure micro-disturbance sampling device for groundwater in highly permeable formations as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. When collecting groundwater samples, the first rotary motor (210) drives the threaded vertical rod (21) to rotate, so that the mounting sleeve (230) moves down along the threaded vertical rod (21), and the mounting horizontal plate (23) also moves down synchronously until the outer sleeve (31) moves down into the sampling well (1). S2. Drive the winding roller (33) to rotate in the forward direction by the second rotary motor (330), so that the winding rope drives the inner collection cylinder (34) to move into the outer sleeve (31) through the through hole (20); S3. The corresponding arc-shaped rotating plate (311) is driven to rotate by the third rotary motor (312) until the two arc-shaped rotating plates (311) rotate to the horizontal direction and contact the well wall of the sampling well (1); S4. Open the first solenoid valve (30) and the second solenoid valve (341). At this time, the groundwater enters the outer casing (31) through the first solenoid valve (30) and enters the collection inner cylinder (34) through the second solenoid valve (341), thus completing the collection of groundwater samples. S5. After the collection is completed, the second rotary motor (330) drives the winding roller (33) to rotate in the opposite direction, and the inner collection cylinder (34) is pulled out from the outer sleeve (31) by the winding rope and discharged through the second solenoid valve (341).

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