Self-dredging type shallow groundwater environment monitoring well structure and method

Abstract

The invention relates to the technical field of environment monitoring wells, and discloses a self-dredging type shallow groundwater environment monitoring well structure and method.The self-dredging type shallow groundwater environment monitoring well structure comprises a monitoring well pipe, a first auxiliary well pipe and a second auxiliary well pipe are arranged on the two sides of the monitoring well pipe, and the bottom ends of the monitoring well pipe and the auxiliary well pipes are communicated through a monitoring well base; a lifting piston is arranged in the monitoring well pipe; the bottom of the lifting piston is connected with a hollow shell; a rotating shaft is arranged at the top of the monitoring well and wound with a lifting steel wire and a reset steel wire, and the winding directions of the reset steel wire and the lifting steel wire are opposite; one end of the lifting steel wire penetrates through the lifting piston to be connected with the hollow shell. One end of the reset steel wire extends in the first auxiliary well pipe and is connected with the bottom of the hollow shell. The rotating shaft is rotated, and the lifting piston and the hollow shell are lifted through the lifting steel wire, so that the lifting piston lifts the sludge in the well to the wellhead of the monitoring well casing; the monitoring well structure has a dredging function, the rotating shaft is rotated, the lifting steel wire is matched with the lifting piston, and sludge can be lifted to a well mouth to be cleaned.

Description

Technical Field

[0001] This invention relates to the field of environmental monitoring well technology, and in particular to a structure and method for a self-cleaning shallow groundwater environmental monitoring well. Background Technology

[0002] In the field of groundwater environmental monitoring, shallow groundwater monitoring wells serve as key infrastructure for monitoring groundwater quality around pollution sources such as enterprises. They play an important role in capturing changes in groundwater quality in real time and accurately assessing the trend of pollution spread. Their normal operation is directly related to the accuracy and continuity of environmental monitoring data, and plays an irreplaceable supporting role in pollution source tracing, risk warning, and ecological and environmental protection decision-making. By regularly collecting groundwater samples through monitoring wells, it is possible to effectively grasp changes in groundwater quality, promptly identify pollution sources, and take corresponding treatment measures.

[0003] However, during their long-term service, shallow groundwater monitoring wells commonly face the problem of clogging caused by aquifer clay particles. Specifically, the fine clay particles widely distributed in shallow groundwater aquifers have a particle size much smaller than the effective pore size of the monitoring well filter media. Under the action of groundwater seepage, these clay particles can easily pass through the filter media layer and continuously enter the well casing through the pores of the monitoring well screen. Since monitoring wells are only used for groundwater monitoring and have a low usage frequency, they often become clogged due to soil sedimentation.

[0004] To address the aforementioned siltation problem, existing technologies primarily employ hydraulic dredging. This involves lowering the drill rod into the well and using equipment such as mud pumps to create a circulating flushing system that removes the silt from the well. However, this method has significant limitations: Firstly, hydraulic dredging requires professional operators and equipment, which greatly increases the complexity of dredging work in monitoring wells. Users of monitoring wells are usually unable to complete the dredging work independently. Secondly, shallow groundwater monitoring wells typically have a small diameter, and the process of lowering the drill pipe into the well can easily cause irreversible mechanical damage to the well casing, compromising the structural integrity of the monitoring well and further shortening its service life.

[0005] Because existing dredging technologies cannot effectively solve the problem of clogging in shallow groundwater monitoring wells, a large number of monitoring wells have been abandoned due to clogging. This not only requires repeated construction of monitoring wells, increasing the time and economic costs of environmental monitoring, but also leads to the interruption of monitoring points, making it impossible to form a continuous groundwater quality monitoring data sequence, which seriously affects the long-term tracking and assessment of groundwater environmental change trends. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a self-cleaning shallow groundwater environmental monitoring well structure and method. By using a lifting steel wire in conjunction with a lifting piston, silt can be lifted to the wellhead for cleaning, solving the problems of complex operation and easy damage to the monitoring well pipe in conventional hydraulic dredging methods.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, a self-cleaning shallow groundwater environment monitoring well structure includes a monitoring well pipe with a first auxiliary well pipe and a second auxiliary well pipe on both sides, the bottom ends of the monitoring well pipe and the auxiliary well pipes being connected through a monitoring well base; a lifting piston is provided inside the monitoring well pipe, and the bottom of the lifting piston is connected to a hollow shell. The monitoring well is equipped with a rotating shaft at the top, on which a lifting steel wire and a reset steel wire are wound. The reset steel wire is wound in the opposite direction to the lifting steel wire. One end of the lifting steel wire passes through the lifting piston and connects to the hollow shell, while the other end of the reset steel wire extends downward inside the first auxiliary well pipe and connects to the bottom of the hollow shell. By rotating the rotating shaft, the lifting piston and the hollow shell are lifted by the lifting steel wire, so that the lifting piston lifts the sludge in the well to the wellhead of the monitoring well pipe.

[0008] As a further implementation, the hollow shell has a rotatable transmission rod arranged horizontally inside and a rotatable rotating shaft arranged vertically. The transmission rod and the rotating shaft are connected by a bevel gear set. The top of the rotating shaft extends upward to the top of the lifting piston and is provided with helical blades. A wire drum is connected to the periphery of the transmission rod. A drive wire is also wound on the rotating shaft. One end of the drive wire extends downward inside the second auxiliary well pipe and passes through the bottom surface of the hollow shell before being wound on the wire drum.

[0009] As a further implementation, the winding direction of the driving steel wire on the rotating shaft is the same as the winding direction of the lifting steel wire. Rotating the rotating shaft causes the driving steel wire to drive the transmission rod to rotate, and the transmission rod drives the rotating shaft to rotate through the bevel gear set, thereby realizing the rotation of the helical blade.

[0010] As a further implementation, the monitoring well base is equipped with a fixed roller, and a reset wire and a drive wire extend along the auxiliary well pipe to the monitoring well base, and achieve reversal by cooperating with the fixed roller.

[0011] As a further implementation, a reciprocating seal is provided between the drive steel wire and the bottom surface of the hollow housing; a rotary seal is provided between the rotating shaft and the position near the top surface of the lifting piston.

[0012] As a further implementation, a first bevel gear is provided at one end of the transmission rod near the rotating shaft, and a second bevel gear is provided on the circumference of the rotating shaft, with the first bevel gear and the second bevel gear engaging.

[0013] As a further implementation, the drive rod is configured with a take-up mechanism so that the wire drum will drive the wire to rewind.

[0014] As a further implementation, two sets of lifting wires are provided, which are symmetrically arranged inside the monitoring well pipe and close to the well wall of the monitoring well pipe; the spiral blades are located between the two sets of lifting wires.

[0015] As a further implementation, a limiting block is provided at the center of the monitoring well base, and the limiting block is higher than the fixed roller.

[0016] Secondly, a dredging method for shallow groundwater environmental monitoring wells, employing any of the above-described self-dredging shallow groundwater environmental monitoring well structures, includes the following steps: When dredging is required, the shaft rotates forward, lifting the lifting piston and hollow shell via the lifting wire. This allows the lifting piston to raise the sludge in the well to the wellhead of the monitoring well pipe. Simultaneously, the driving wire pulls the wire drum to rotate, causing the rotating rod to drive the rotating shaft through the bevel gear set, thus rotating the helical blades. The helical blades disturb the sludge. After the sludge is cleared, the shaft rotates in reverse, resetting the wire to pull the lifting piston and hollow shell downward. The wire drum then winds up the driving wire through the winding mechanism.

[0017] The beneficial effects of the present invention are as follows: 1. The monitoring well is equipped with a monitoring well pipe and an auxiliary well pipe, and is equipped with a rotating shaft, lifting wire, reset wire, lifting piston and hollow shell. During dredging, only the rotating shaft needs to be controlled to rotate. The lifting wire and lifting piston can be used to lift the sludge to the wellhead for cleaning, which solves the problem of conventional hydraulic dredging methods being complicated to operate and easy to damage the monitoring well pipe.

[0018] 2. A rotating shaft and a transmission rod are installed inside the hollow shell. The rotating shaft and the transmission rod are connected by a bevel gear set. A spiral blade is installed at the top of the rotating shaft. The driving steel wire extends downward through the second auxiliary well pipe and is wound on the steel wire drum. During the process of lifting silt, the spiral blade can effectively disturb the soil that may be solidified on the monitoring well wall, reducing the resistance caused by the solidification of soil on the monitoring well wall during the piston rise.

[0019] 3. The limit stop is higher than the fixed roller, which can prevent the fixed roller from being crushed when the hollow shell is lowered and reset; the setting of two sets of lifting steel wires allows the lifting piston to be lifted smoothly along the axis and the force is balanced. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] Figure 1 This is a schematic diagram of the structure of a groundwater environment monitoring well in an embodiment of the present invention; Figure 2 This is a top view of a groundwater environment monitoring well in an embodiment of the present invention; Figure 3 This is a cross-sectional view of a groundwater environment monitoring well in an embodiment of the present invention; Figure 4 This is a cross-sectional view of the bottom of the groundwater environment monitoring well in an embodiment of the present invention.

[0022] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0023] Among them: 10. Monitoring well solid pipe, 20. First auxiliary well pipe, 30. Second auxiliary well pipe, 40. Monitoring well base, 101. Monitoring well screen pipe; 1. Rotary shaft, 11. Rotary shaft support, 12. Drive wire, 13. Lifting wire, 14. Reset wire; 2. Lifting piston, 21. Rotary seal, 22. Connecting buckle, 3. Hollow shell, 31. Fixing plate, 4. Limiting block, 5. Fixing roller, 6. Fixing roller, 7. Rotary shaft, 8. Helical blade, 9. Transmission rod, 91. Wire drum, 92. Reciprocating seal, 93. First bevel gear, 71. Second bevel gear. Detailed Implementation

[0024] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0025] Example 1 In a typical embodiment of the present invention, reference is made to Figures 1-4 As shown, a self-dredging shallow groundwater environment monitoring well structure includes a monitoring well pipe and an auxiliary well pipe, wherein the auxiliary well pipe is located on both sides of the monitoring well pipe, the top of the monitoring well pipe and the auxiliary well pipe are open, and the bottom is connected through the monitoring well base 40.

[0026] like Figure 1 and Figure 2 As shown, the auxiliary well casing includes a first auxiliary well casing 20 and a second auxiliary well casing 30, which are respectively arranged on both sides of the monitoring well casing and are equivalent to being symmetrically arranged. The monitoring well casing consists of a monitoring well solid casing 10 and a monitoring well screen casing 101 with the same inner diameter. In this embodiment, the monitoring well screen casing is located in the middle of the monitoring well casing, and the monitoring well screen casing 101 is connected to the monitoring well solid casing vertically.

[0027] A lifting piston 2 is installed inside the monitoring well casing, and the bottom of the lifting piston 2 is connected to a hollow shell 3. The outer diameter of the lifting piston 2 and the hollow shell 3 is adapted to the inner diameter of the monitoring well casing. A rotating shaft 1 is horizontally installed at the top of the monitoring well, and the rotating shaft 1 is rotatably supported by a rotating shaft bracket 11. A lifting steel wire and a reset steel wire are wound on the rotating shaft 1, and one end of the lifting steel wire and the reset steel wire is fixed to the rotating shaft. The winding direction of the reset steel wire 14 is opposite to that of the lifting steel wire 13. One end of the lifting steel wire 13 passes through the lifting piston and connects to the hollow shell, and one end of the reset steel wire extends downward inside the first auxiliary well casing and connects to the bottom of the hollow shell.

[0028] By rotating the shaft, the lifting piston and hollow shell are lifted using the lifting steel wire, so that the lifting piston lifts the sludge in the well to the wellhead of the monitoring well pipe, thereby cleaning the sludge and completing self-cleaning (i.e., it has its own sludge cleaning function and does not require special sludge cleaning equipment).

[0029] In this embodiment, the lifting piston can be a waterproof silicone piston, and the bottom of the lifting piston is provided with a hollow shell. The top of the hollow shell 3 is provided with a connecting buckle, and the hollow shell 3 is fixed to the lifting piston 2 by the connecting buckle 22. The two rise and fall synchronously. One end of the lifting wire passes through the lifting piston and connects to the connecting buckle 22 of the hollow shell. The lifting wire can pull the lifting piston 2 and the hollow shell 3 upward synchronously through the connecting buckle 22.

[0030] like Figure 3 As shown, two fixed rollers 5 are provided on the left side of the monitoring well base 40. One fixed roller 5 is located directly below the first auxiliary well pipe 20, and the other fixed roller 5 is located inside the monitoring well pipe. One end of the reset steel wire extends downward inside the first auxiliary well pipe to the monitoring well base 40, and cooperates with the fixed roller 5. After being redirected by the fixed roller 5, it is fixedly connected to the bottom of the hollow shell.

[0031] When the shaft 1 rotates forward, the lifting piston 2 is lifted. After dredging, the shaft 1 rotates in reverse, and the reset wire pulls the hollow shell 3 down, which drives the lifting piston 2 to reset. The lifting piston 2 returns to the lower end of the monitoring well pipe.

[0032] like Figure 3 and Figure 4 As shown, considering the problem of silt solidification above the lifting piston 2, in order to reduce the difficulty of dredging, this embodiment is equipped with a spiral blade 8 to both lift and disturb the silt.

[0033] Specifically, the hollow shell 3 has a horizontally rotatable transmission rod inside and a vertically rotatable rotating shaft. The transmission rod and the rotating shaft are connected by a bevel gear set. The top of the rotating shaft extends upward to the top of the lifting piston and is equipped with a spiral blade 8.

[0034] The bottom end of the rotating shaft 7 is connected to the bearing seat at the center of the bottom surface of the hollow housing 3. Correspondingly, the bottom and the center position near the top of the lifting piston 2 are also provided with bearing seats, which are matched with the rotating shaft so that the rotating shaft 7 can rotate smoothly.

[0035] The transmission rod 9 is located on the side of the rotating shaft 7 near the second auxiliary well pipe 30, such as... Figure 4 As shown, the right end of the transmission rod 9 is engaged with the bearing seat on the inner wall of the hollow shell 3. A fixing plate 31 is also provided inside the hollow shell 3 near the left end of the transmission rod 9. The fixing plate 31 is provided with a bearing seat. The left end of the transmission rod 9 extends to the rotating shaft 7 after passing through the bearing seat on the fixing plate 31.

[0036] A first bevel gear 93 is provided at the left end of the transmission rod 9, and a second bevel gear 71 is provided on the circumference of the corresponding position of the rotating shaft 7. The first bevel gear 93 and the second bevel gear 71 cooperate. A wire drum is fixedly connected to the circumference of the transmission rod 9 between the two bearing seats that cooperate with the transmission rod 9.

[0037] like Figure 3 As shown, a drive wire 12 is also wound on the rotating shaft. One end of the drive wire 12 is fixed on the rotating shaft. The winding direction of the drive wire 12 on the rotating shaft is the same as the winding direction of the lifting wire. The other end of the drive wire extends downward inside the second auxiliary well pipe and passes through the bottom surface of the hollow shell before being wound on the wire drum, and the end point is fixed thereto.

[0038] Specifically, two fixed rollers 6 are located on the right side of the bottom surface of the monitoring well base. One roller is located directly below the second auxiliary well pipe 30, and the other is located inside the monitoring well pipe. The drive wire cooperates with the fixed rollers 6, and after being redirected by the fixed rollers 6, it passes upward through the bottom surface of the hollow shell and winds onto the wire reel 91. The fixed rollers effectively reduce the resistance during the movement of the wire.

[0039] It is understandable that a reciprocating seal 92 is provided between the drive steel wire 12 and the bottom surface of the hollow housing 3, and a rotary seal 21 is provided between the rotating shaft and the top surface near the lifting piston to prevent sludge from entering the interior of the hollow housing or between the rotating shaft and the lifting piston. The reciprocating seal 92 and the rotary seal 21 are existing technologies, and structures with better sealing performance can be selected as needed.

[0040] By rotating the shaft, the drive wire 12 can drive the wire drum 91 and the transmission rod 9 to rotate. The transmission rod 9 drives the rotating shaft 7 to rotate through the bevel gear set, thereby realizing the rotation of the spiral blade 8. As the lifting piston 3 pushes the silt upward, the spiral blade 8 effectively disturbs the soil that may be solidified on the monitoring well wall, reducing the resistance caused by the solidification of soil on the monitoring well wall during the upward movement of the lifting piston 3, and reducing the difficulty of dredging.

[0041] After the dredging is completed, the rotating shaft 1 needs to be reversed so that the lifting piston 3 is lowered back below the monitoring well screen pipe 101. When the rotating shaft 1 is reversed, the lifting steel wire 13 and the driving steel wire 12 wound on the rotating shaft 1 are released, and the reset steel wire 14 is tightened and continues to be wound on the rotating shaft 1. Under the pull of the end of the reset steel wire 14 on the hollow shell, the lifting piston completes the lowering and reset.

[0042] After the lifting piston 2 is lifted, the drive wire 12 on the wire 91 is released. The transmission rod 9 is equipped with a take-up mechanism so that when the wire drum 91 resets, it will rewind the drive wire 12 to complete the take-up. It can be understood that the transmission rod is set as a structure with energy storage elements such as springs and has an automatic take-up function, so that when the drive wire is in a relaxed state, the horizontal transmission rod can automatically retract and wind it. The automatic take-up structure is existing technology and will not be described in detail here.

[0043] A limit block 4 is provided at the center of the monitoring well base, and the height of the limit block 4 is higher than that of the fixed roller. The purpose is to protect the fixed roller and prevent the hollow shell from crushing the fixed roller during reset.

[0044] like Figure 3 As shown, two sets of lifting wires 13 are arranged symmetrically inside the monitoring well pipe and close to the well wall; the spiral blades 8 are located between the two sets of lifting wires 13. The spiral blades 8 are configured such that they do not touch the lifting wires 13 or the well wall during rotation, with the blade tip close to the well wall, thereby disturbing any soil that may be stuck to the well wall during rotation.

[0045] In this example, the steel wire, transmission rod, connecting buckle, hollow shell, spiral blade, bevel gear set, limit block, and monitoring well base are made of waterproof stainless steel. The fixed roller is made of waterproof stainless steel shaft with a waterproof high-strength engineering plastic wheel body. The piston is made of waterproof silicone. The well pipe is made of PVC, which is commonly used in shallow groundwater monitoring wells.

[0046] Example 2 like Figures 1-4 As shown, a dredging method for a shallow groundwater environmental monitoring well, employing the self-dredging shallow groundwater environmental monitoring well structure of Example 1, includes the following steps: In the normal static state, the lifting piston 2, the hollow shell 3 and the internal structural components are located at the bottom of the monitoring well, and the upper surface of the lifting piston 2 is located below the monitoring well screen tube, ensuring the normal flow of groundwater in the monitoring well.

[0047] When a monitoring well becomes clogged, it needs to be dredged. By controlling the rotation and direction of the shaft, the lifting and driving wires are tightened, and the reset wire is loosened. The lifting wire pulls the piston and the sludge above it upwards towards the wellhead. The lifting piston lifts the sludge in the well to the wellhead of the monitoring well pipe. Tools such as shovels can be used to clean the sludge.

[0048] Simultaneously, the driving wire pulls the wire drum to rotate, causing the rotating rod to drive the rotating shaft to rotate through the bevel gear set, thereby rotating the spiral blades. The spiral blades disturb the silt, causing them to rotate and effectively disturb the soil that may be solidified on the monitoring well wall, reducing the resistance caused by the soil solidification on the monitoring well wall during the piston's ascent.

[0049] After the silt in the monitoring well is discharged through the lifting piston, the shaft is reversed, and the reset wire pulls the lifting piston and the hollow shell down. The wire drum winds up the drive wire through the winding mechanism, realizing the automatic recovery and winding of the drive wire to ensure normal use for the next monitoring well dredging operation.

[0050] In addition, groundwater that may enter the well pipe below the bottom surface of the hollow cargo carrier shell through the screen pipe during the upward movement of devices such as pistons can be extracted by placing a pumping pipe in the auxiliary well pipe.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A self-cleaning shallow groundwater environmental monitoring well structure, characterized in that, It includes a monitoring well casing, with a first auxiliary well casing and a second auxiliary well casing on both sides. The bottom ends of the monitoring well casing and the auxiliary well casing are connected through a monitoring well base. A lifting piston is installed inside the monitoring well casing, and the bottom of the lifting piston is connected to a hollow shell. The monitoring well is equipped with a rotating shaft at the top, on which a lifting steel wire and a reset steel wire are wound. The reset steel wire is wound in the opposite direction to the lifting steel wire. One end of the lifting steel wire passes through the lifting piston and connects to the hollow shell, while the other end of the reset steel wire extends downward inside the first auxiliary well pipe and connects to the bottom of the hollow shell. By rotating the rotating shaft, the lifting piston and the hollow shell are lifted by the lifting steel wire, so that the lifting piston lifts the sludge in the well to the wellhead of the monitoring well pipe.

2. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 1, characterized in that, The hollow shell has a horizontally rotatable transmission rod and a vertically rotatable rotating shaft inside. The transmission rod and the rotating shaft are connected by a bevel gear set. The top of the rotating shaft extends upward to the top of the lifting piston and is equipped with helical blades. A wire drum is connected to the periphery of the transmission rod. A drive wire is also wound on the rotating shaft. One end of the drive wire extends downward inside the second auxiliary well pipe and passes through the bottom surface of the hollow shell before being wound on the wire drum.

3. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 2, characterized in that, The winding direction of the driving steel wire on the rotating shaft is the same as the winding direction of the lifting steel wire. Rotating the rotating shaft causes the driving steel wire to drive the transmission rod to rotate, and the transmission rod drives the rotating shaft to rotate through the bevel gear set, thereby realizing the rotation of the spiral blade.

4. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 3, characterized in that, The monitoring well base is equipped with a fixed roller, and the reset steel wire and drive steel wire extend along the auxiliary well pipe to the monitoring well base, and achieve reversal by cooperating with the fixed roller.

5. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 2, characterized in that, A reciprocating seal is provided between the drive steel wire and the bottom surface of the hollow housing; a rotary seal is provided between the rotating shaft and the top surface near the lifting piston.

6. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 3, characterized in that, A first bevel gear is provided at one end of the transmission rod near the rotating shaft, and a second bevel gear is provided on the circumference of the rotating shaft. The first bevel gear and the second bevel gear cooperate with each other.

7. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 6, characterized in that, The drive rod is equipped with a take-up mechanism so that the wire drum can drive the wire to rewind.

8. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 2, characterized in that, Two sets of lifting wires are provided, which are symmetrically arranged inside the monitoring well pipe and close to the well wall of the monitoring well pipe; the spiral blades are located between the two sets of lifting wires.

9. The structure of a self-cleaning shallow groundwater environmental monitoring well according to claim 4, characterized in that, The monitoring well base is equipped with a limiting block at its center, which is higher than the fixed roller.

10. A method for dredging shallow groundwater environmental monitoring wells, characterized in that, The self-cleaning shallow groundwater environmental monitoring well structure as described in any one of claims 1-9 includes the following steps: When dredging is required, the shaft rotates forward, lifting the lifting piston and hollow shell via the lifting wire. This allows the lifting piston to raise the sludge in the well to the wellhead of the monitoring well pipe. Simultaneously, the driving wire pulls the wire drum to rotate, causing the rotating rod to drive the rotating shaft through the bevel gear set, thus rotating the helical blades. The helical blades disturb the sludge. After the sludge is cleared, the shaft rotates in reverse, resetting the wire to pull the lifting piston and hollow shell downward. The wire drum then winds up the driving wire through the winding mechanism.

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