A rectangular pile impact hole anti-twist device

Abstract

The invention discloses a rectangular pile impact hole anti-twist device, which belongs to the field of anti-slip pile construction technology, including an impact drill, an upper steel wire rope, a guide steel casing, an anti-twist hanger, a lower steel wire rope, and a rectangular drill bit. The guide steel casing is fixed to the inner wall of the wellhead, and the impact drill is connected to the rectangular anti-twist hanger through the upper steel wire rope. The anti-twist hanger is slidably matched with the guide steel casing, and the four corners of the anti-twist hanger are respectively connected to the four corners of the rectangular drill bit through the vertical lower steel wire rope; the anti-twist hanger includes a frame, an upper hanging point, a guide wheel, a spring damping box and a lifting ring, and the impact drill is connected to the lifting ring of the anti-twist hanger through the upper steel wire rope, and the lifting ring is connected to the frame through the spring damping box, and the guide wheels are distributed around the frame, and the frame cooperates with the guide steel casing through the guide wheel, and the frame is connected to the lower steel wire rope through the upper hanging point. The device of the invention adopts a four-point hanging form, controls the spatial position of the drill bit, balances the force of the impact drill bit, and ensures the quality of pile formation.

Description

Technical Field

[0001] The invention belongs to the technical field of anti-slide pile construction, and in particular relates to an anti-twist device for rectangular pile impact hole forming. Background Art

[0002] With the continuous improvement of highway and railway networks, the geology that the lines need to cross is becoming more and more complex. Anti-slip piles are undoubtedly an effective structure to prevent slope sliding. At present, most anti-slip piles are designed as rectangular piles. It is difficult for existing mechanical equipment to construct rectangular piles. Conventional construction uses manual excavation and water-grinding drilling. The daily construction footage of each hole is 0.3-0.6m, and the construction speed is slow. During the hole digging process, the working space is small, the geological environment is complex, and the personnel are working in the hole, which poses a great safety risk. In order to solve the problems of high construction safety risks and slow construction speed in the construction of anti-slip piles, the existing technology usually adopts a construction process for rectangular pile impact drilling, but this process has the following problems: 1. Since conventional rectangular pile drilling uses a single hoisting rope to connect a rectangular drill bit, the rectangular drill bit is prone to horizontal twisting during the drilling process. The flatness of the hole wall after forming is poor, and the hole cannot be inspected, resulting in the inability to hang the steel cage. In addition, due to the twisting of the pile body, the pile body cannot achieve the designed anti-slip capacity, affecting the operational safety of the road network.

[0003] 2. When encountering complex geological conditions such as obliquely developed rock strata, "one side soft and the other side hard" geology, or locally protruding isolated hard rocks, there are no effective measures to correct the deviation, resulting in difficulty in drilling. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a rectangular pile impact hole anti-twisting device, which adopts a four-point suspension form to control the spatial position of the drill bit, prevent drilling twisting, balance the force of the impact drill bit, and ensure the quality of pile formation.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: The present invention discloses a rectangular pile impact hole anti-twist device, comprising an impact drill, an upper steel wire rope, a guide steel casing, an anti-twist hanger, a lower steel wire rope, and a rectangular drill bit, wherein the guide steel casing is fixed to the inner wall of a wellhead, the impact drill is connected to the rectangular anti-twist hanger through the upper steel wire rope, the anti-twist hanger is slidably matched with the guide steel casing, and the four corners of the anti-twist hanger are respectively connected to the four corners of the rectangular drill bit through the vertical lower steel wire rope; the anti-twist hanger comprises a frame body, an upper hanging point, a guide wheel, a spring damping box and a lifting ring, the impact drill is connected to the lifting ring of the anti-twist hanger through the upper steel wire rope, the lifting ring is connected to the frame body through the spring damping box, the guide wheels are distributed around the frame body, the frame body is matched with the guide steel casing through the guide wheels, and the frame body is connected to the lower steel wire rope through the upper hanging point.

[0006] Furthermore, a plurality of sleeves are evenly spaced apart on the outside of the lower steel wire rope along the length direction thereof, the lower steel wire rope is connected to the sleeves via a fastening connector, a pivot seat is provided at one end of the sleeve, a pivot shaft is installed on the pivot seat, a pivot hole corresponding to the pivot shaft is provided at the other end of the sleeve, and an elastic buffer assembly is installed between two adjacent sleeves.

[0007] Furthermore, the pivots of two adjacent groups of sleeves are staggered in the circumferential direction of the sleeves.

[0008] Furthermore, the elastic buffer assembly includes a spring, a support plate, a spring wave plate, and a screw. The spring wave plate is installed in the gap between two adjacent sleeves. Support plates are fixed at both ends of the spring wave plate. The support plate is connected to the sleeve by screws. The two ends of the spring are respectively connected to the two sleeves; the crests and troughs of the spring wave plate are respectively abutted against the end faces of the two adjacent sleeves.

[0009] Furthermore, the sleeve includes a front tube, a rear tube and a flexible tube which are coaxially arranged, the pivot and the pivot hole are respectively connected to the front tube and the rear tube, and both ends of the flexible tube are respectively fixedly connected to the front tube and the rear tube.

[0010] Furthermore, the sleeve includes a first semi-cylinder and a second semi-cylinder, one side of the first semi-cylinder is pivotally connected to one side of the second semi-cylinder, and the other side of the first semi-cylinder is detachably connected to the other side of the second semi-cylinder.

[0011] Furthermore, the fastening connector includes a first semicircular plate and a second semicircular plate, which are enclosed on the outer side of the lower wire rope, and mounting seats are correspondingly arranged on the first semicircular plate and the second semicircular plate. Through holes are provided on the mounting seat and the sleeve, and a screw is passed through the through hole. The mounting seat and the screw are fixed by a first nut, and the sleeve and the screw are fixed by a second nut.

[0012] Furthermore, arc-shaped grooves are formed on the inner sides of the first semicircular plate and the second semicircular plate, and elastic fastening rings are installed in the arc-shaped grooves.

[0013] The beneficial effects of the present invention are: The invention discloses a rectangular pile impact hole anti-twist device. 1. By setting a rectangular anti-twist hanger to cooperate with the guide steel casing, the anti-twist hanger is constrained by the rectangular guide steel casing and can only move up and down but cannot rotate horizontally. Several guide wheels are set on the four sides of the anti-twist hanger to fit closely with the guide steel casing, reducing the friction between the hanger and the guide steel casing and controlling the horizontal position of the hanger.

[0014] 2. The anti-twist hanger drives the rectangular drill bit to do lifting and impact work through 4 lower steel wire ropes of equal length. During the drill bit impact construction process, no matter what stratum is encountered, the rectangular drill bit is controlled by the 4 steel wire ropes and can only move up and down pistons, but cannot rotate horizontally, thus achieving the anti-twist goal. Since the forces of the four steel wire ropes are basically balanced and basically symmetrically distributed, the force center point of the drill bit is accurately aligned with the force center point on the top seat, avoiding the initial unbalanced force that causes the drill bit to rotate from the source.

[0015] 3. As the impact depth increases, the lower wire rope can be extended before the anti-twist hanger is separated from the guide steel casing, so as to always ensure that the anti-twist hanger works in the guide steel casing, saving costs.

[0016] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art may be taught from the practice of the present invention. The objectives and other advantages of the present invention may be achieved through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration: Figure 1 It is a schematic structural diagram of the anti-twist device of the present invention; Figure 2 It is a top view of the anti-twist hanger; Figure 3 It is a structural schematic diagram of the sleeve string; Figure 4 is a cross-sectional view of the sleeve string; Figure 5 This is a schematic diagram of the structure of the sleeve of Example 1; Figure 6 It is a structural schematic diagram of the elastic buffer component; Figure 7 is a schematic diagram of the structure of the fastening connector; Figure 8 It is a schematic diagram of the structure of the sleeve of Example 2.

[0018] The markings in the accompanying drawings are as follows: impact drill 1, upper wire rope 2, guide steel casing 3, anti-twist hanger 4, lower wire rope 5, frame 6, upper hanging point 7, guide wheel 8, spring damping box 9, lifting eye 10, sleeve 11, fastening connector 12, pivot seat 13, pivot 14, pivot hole 15, elastic buffer assembly 16, spring 17, support plate 18, spring wave plate 19, screw 20, front cylinder 21, rear cylinder 22, flexible cylinder 23, first semi-cylinder 24, second semi-cylinder 25, first semi-circular plate 26, second semi-circular plate 27, mounting seat 28, through hole 29, screw 30, first nut 31, second nut 32, arc groove 33. DETAILED DESCRIPTION

[0019] Embodiment 1, as Figures 1 to 7 As shown, the present invention discloses a rectangular pile impact hole anti-twist device, comprising an impact drill 1, an upper steel wire rope 2, a guide steel casing 3, an anti-twist hanger 4, a lower steel wire rope 5, and a rectangular drill bit. The impact drill 1 is used to lift the upper steel wire rope 2 to drive the anti-twist hanger 4 to move up and down, and the anti-twist hanger 4 drives the rectangular drill bit through four lower steel wire ropes 5, so that the impact drill bit has a certain potential energy, which is convenient for subsequent impact work.

[0020] The guide steel casing 3 is fixed to the inner wall of the wellhead, and the overall scale of the guide steel casing 3 is consistent with the scale of the inner wall of the wellhead. In some other embodiments, the guide steel casing 3 is fixed to the ground by reinforcing steel, thereby ensuring that the guide steel casing 3 has sufficient strength and rigidity, and ensuring that the geometric shape of the steel casing at the hole mouth position is not deformed under the influence of drilling rigs, material stacking, hoisting and other operations near the hole mouth, otherwise it may affect the normal operation of the anti-twist hanger 4 in the guide steel casing 3. In the embodiment of the present invention, the guide steel casing 3 is composed of a 5-10mm steel panel and a steel back rib. The main function of the guide steel casing 3 is to provide a stable rectangular space for the anti-twist hanger 4, so a certain strength and rigidity are guaranteed, and the rigidity is enhanced by measures such as the steel back rib.

[0021] When the conditions on site are met, in some other embodiments, the guide steel casing 3 can also adopt a guide reinforced concrete wall with a height of about 2.5m-3m, which is composed of locking concrete, guide concrete wall and the like.

[0022] The impact drill 1 is connected to the rectangular anti-twist hanger 4 through the upper steel wire rope 2. The anti-twist hanger 4 is slidably matched with the guide steel casing 3. The four corners of the anti-twist hanger 4 are respectively connected to the four corners of the rectangular drill bit through the vertical lower steel wire rope 5. Since the forces on the four steel wire ropes are basically balanced and basically symmetrically distributed, the force center point of the drill bit is accurately aligned with the force center point on the top seat to avoid the initial unbalanced force that causes the drill bit to rotate from the source. Because the anti-twist hanger 4 can only work in the guide steel casing 3, as the pile length increases, the lower steel wire rope 5 must be extended in sections. In order to adapt to the height of the guide steel casing 3, a customized 2m module is adopted, one end is a plug-in annular rope buckle, and the other end is a pressed shackle type joint. According to the pile length requirements, 4m, 6m, 8m and other steel wire ropes can be selected as replacements.

[0023] Specifically, the anti-twist hanger 4 disclosed in the present invention includes a frame 6, a hanging point 7, a guide wheel 8, a spring damping box 9 and a lifting ring 10. The frame 6 has sufficient strength and rigidity to bear the load of the impact drill bit. The rectangular drill bit is lifted by the steel wire rope connected by the four hanging points 7, so that the impact drill bit has a certain potential energy; when the drilling rig relaxes and drops the anti-twist hanger 4, the four hanging points 7 synchronously relax the steel wire rope 5, and the potential energy of the impact drill bit is converted into kinetic energy to impact the rock formation at the bottom of the pile. The impact drill 1 is connected to the lifting ring 10 of the anti-twist hanger 4 through the upper steel wire rope 2, and the lifting ring 10 is connected to the frame 6 through the spring damping box 9, and the spring damping box 9 is composed of more than 4 springs 17 and a damper. The impact load formed by the anti-twist hanger 4 due to its own weight is reduced, which plays a role in protecting the hanger, the upper steel wire rope 2 and the drilling rig. The guide wheels 8 are distributed around the frame 6. The frame 6 cooperates with the guide steel casing 3 through the guide wheels 8 to ensure that the crane can move freely up and down in the guide steel casing 3 to avoid excessive resistance affecting the impact kinetic energy. The frame 6 is connected to the lower wire rope 5 through the upper hanging point 7.

[0024] In the present embodiment, a plurality of sleeves 11 are evenly spaced apart on the outer side of the lower steel wire rope 5 along the length direction of the lower steel wire rope 5. The lower steel wire rope 5 is connected to the sleeve 11 via a fastening connector 12. A pivot seat 13 is provided at one end of the sleeve 11. A pivot 14 is installed at the pivot seat 13. A pivot hole 15 corresponding to the pivot 14 is provided at the other end of the sleeve 11. An elastic buffer assembly 16 is installed between two adjacent sleeves 11.

[0025] Since the rectangular drill bit will generate reverse torque due to air resistance or well wall impact, when the rectangular drill bit has a tendency to rotate, the elastic buffer component 16 can offset part of the rotational power, inhibit the occurrence and aggravation of rotation, and ensure the stability of the rectangular drill bit. The present invention arranges a sleeve 11 on the outside of the wire rope. When the wire rope is bent by force, the elastic buffer component 16 between the sleeves 11 can effectively balance the force of the drill bit during the lowering process or the hole-forming process, and can adapt to the slight uneven force during the falling process, decompose the unbalanced force, avoid the accumulation of rotational torque, and keep the rectangular drill bit in a stable posture.

[0026] The working principle and process of the device of the present invention are as follows: Construction conditions for rectangular pile impact drilling: 1. Clay, silt, sand, fill, gravel, boulder and gravel layers, and strong or weak weathered rock layers; 2. Suitable for flat terrain, steep mountains with a slope of less than 45 degrees, large construction sites, and need to dig mud pools, sludge pools and other foundation pits on site; sufficient water sources on site; 3. The construction access road at the pile position can meet the passage of large-scale mechanical equipment. After the hole is impacted, a truck crane is required to lift the steel cage and pour concrete.

[0027] 2. Impact hole construction process: 1. Rectangular drill bit and anti-twist hanger 4 processing It is processed and customized according to the size of the rectangular pile, and the hanger is designed and processed according to the drawings; four transparent hollow rectangular bodies are arranged inside the drill bit, and the bottom of the rectangular drill bit is filled with semi-elliptical impact teeth at intervals.

[0028] 2. Pile position setting During construction survey and layout, the design coordinates are used to lay out the lines, measure and lay out the corner points of the rectangular piles, and use white lime to mark the edges. Gantry piles are set outside the piles so that the pile positions can be corrected at any time.

[0029] 3. Guide steel casing 3 or concrete wall construction The guide steel casing 3 is assembled at the pile position. The excavation is carried out by excavators and manual labor. The wellhead is dug to a depth of about 2 m according to the hole section of the pile hole, and then hoisted into it, backfilled around and fixed with lock steel. The concrete retaining wall is first cast in the lock mouth according to the designed size, and then excavated layer by layer, 1.2-1.5m each time, and then the retaining wall steel bars are tied, and the retaining wall concrete is cast by erecting the formwork. After the upper layer of concrete reaches a certain strength, the second layer is excavated downwards, and the construction is carried out in sequence to the designed position.

[0030] 4. Impact drill 1 is in place The impact drill 1 is installed in place by a crane, and the drill is leveled by sleepers or pad beams so that the drill rod is vertical and the center of the drill bit coincides with the center of the pile, with a deviation of no more than ±20 mm.

[0031] 5. Impact Drilling Machine 1 Hole Construction 1) At the pile position, first directly connect the rectangular drill bit and the drill wire rope, and impact to a certain depth, such as 1-2m below the guide steel casing 3, to form a certain working space.

[0032] 2) Connect the rectangular drill bit and the anti-twist hanger 4 with a wire rope, lift the anti-twist hanger 4 together with the rectangular drill bit with a crane and move them into the hole, and finally connect the impact drill winch wire rope to the lifting ring 10 at the upper end of the anti-twist hanger 4.

[0033] 3) After the winch of the drilling rig is lifted, it is released to make the drill bit free fall and impact the soil downward. The impact teeth at the bottom of the drill bit can enhance the impact effect and crush the hard soil or rock within the impact range into fine particles, which are then discharged from the pile hole along with the mud through the hollow cube on the drill bit.

[0034] 4) When the anti-twist hanger 4 is about to detach from the guide steel casing 3, the lower steel wire rope 5 is replaced or extended by 2m before continuing the impact construction. It must be ensured that the anti-twist hanger 4 always works in the guide steel casing 3.

[0035] 5) When the hole is punched to the design elevation of the bearing layer, the pile hole shall be inspected and accepted immediately. After the acceptance is qualified, the first hole cleaning shall be carried out, and the hole cleaning shall be carried out by the slurry replacement method.

[0036] 7. Fabrication and installation of steel cage The steel cage of bored piles is processed into semi-finished products in the steel processing plant, transported to the construction site by flatbed trucks, and tied into 9m sections beside the pile hole. Transverse reinforcing steel bars are added to the steel cage to prevent deformation. The cage is lifted into the pile hole in sections by a crane for extension and lowering.

[0037] 8. Catheter installation The conduit is made of seamless steel pipe. It is lowered vertically during installation and located in the center of the hole. The conduit mouth is controlled to be 0.3 to 0.4m away from the bottom of the hole.

[0038] 9. Secondary hole cleaning Since the installation of the steel cage and the conduit takes a long time, in order to ensure that the sediment thickness at the bottom of the hole meets the design and specification requirements, the hole depth is tested again after the steel cage and the conduit are installed. If the sediment thickness does not meet the requirements, the hole is cleaned again immediately.

[0039] 10. Concrete pouring Rectangular piles are poured with underwater concrete. The first batch of concrete is poured using the plugging method. The amount of concrete poured ensures that the initial buried depth of the conduit is ≮1.0m. The buried depth of the normal poured conduit is controlled at 2 to 6m. To ensure the quality of the pile body, it is necessary to pour to 0.5 to 1m above the designed pile top, conduct relevant tests on site and record the entire pouring process.

[0040] In this embodiment, the pivots 14 of two adjacent groups of sleeves 11 are staggered in the circumferential direction of the sleeves 11, which can increase the bending freedom of the sleeve string 11 and meet the needs of bending buffering of the lower wire rope 5 in at least two directions.

[0041] In this embodiment, the elastic buffer assembly 16 includes a spring 17, a support plate 18, a spring wave plate 19, and a screw 20. The spring wave plate 19 is installed in the interval between two adjacent sleeves 11. The spring wave plate 19 is made of spring 17 steel material, and can elastically buffer the axis between the sleeves 11 when it changes. Support plates 18 are fixed at both ends of the spring wave plate 19, and the support plates 18 are connected to the sleeves 11 by screws 20. The support plates 18 can be easily installed and replaced. The two ends of the spring 17 are respectively connected to the two sleeves 11; the crests and troughs of the spring wave plate 19 are respectively in contact with the end faces of the two adjacent sleeves 11, so that sudden buffering can be handled at any time.

[0042] In this embodiment, the sleeve 11 includes a front cylinder 21, a rear cylinder 22 and a flexible cylinder 23 which are coaxially arranged. The pivot 14 and the pivot hole 15 are respectively connected to the front cylinder 21 and the rear cylinder 22. The two ends of the flexible cylinder 23 are respectively fixedly connected to the front cylinder 21 and the rear cylinder 22. The flexible cylinder 23 adopts a flexible rubber cylinder. By providing a deformable flexible cylinder 23, the sleeve 11 can further adapt to the bending changes of the lower wire rope 5, reduce the interference between the inner wall of the sleeve 11 and the wire rope, and increase the life of the device.

[0043] Embodiment 2, as Figure 8 As shown, the difference from Example 1 is that, in this embodiment, the sleeve 11 includes a first semi-cylinder 24 and a second semi-cylinder 25, one side of the first semi-cylinder 24 is pivotally connected to one side of the second semi-cylinder 25, and the other side of the first semi-cylinder 24 is detachably connected to the other side of the second semi-cylinder 25, so that the sleeve 11 can be conveniently installed on the outside of the lower wire rope 5 at a later time, which saves construction time and is also convenient for maintenance and replacement.

[0044] In this embodiment, the fastening connector 12 includes a first semicircular plate 26 and a second semicircular plate 27, which are enclosed on the outer side of the lower wire rope 5, and a mounting seat 28 is correspondingly provided on the first semicircular plate 26 and the second semicircular plate 27. A through hole 29 is provided on the mounting seat 28 and the sleeve 11, and a screw 30 is passed through the through hole 29. The mounting seat 28 and the screw 30 are fixed by a first nut 31, and the sleeve 11 and the screw 30 are fixed by a second nut 32. By adopting the above arrangement, the lower wire rope 5 and the sleeve 11 can be conveniently connected together to prevent relative displacement between the two.

[0045] In this embodiment, an arc groove 33 is formed on the inner side of the first semicircular plate 26 and the second semicircular plate 27. An elastic fastening ring is installed in the arc groove 33 to make the connection between the sleeve 11 and the lower wire rope 5 more secure.

[0046] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A rectangular pile impact hole anti-twist device, characterized in that: It includes an impact drill, an upper steel wire rope, a guide steel casing, an anti-twist hanger, a lower steel wire rope, and a rectangular drill bit. The guide steel casing is fixed to the inner wall of the wellhead. The impact drill is connected to the rectangular anti-twist hanger through the upper steel wire rope. The anti-twist hanger is slidably matched with the guide steel casing. The four corners of the anti-twist hanger are respectively connected to the four corners of the rectangular drill bit through the vertical lower steel wire rope. The anti-twist hanger includes a frame body, an upper hanging point, a guide wheel, a spring damping box and a lifting ring. The impact drill is connected to the lifting ring of the anti-twist hanger through the upper steel wire rope, and the lifting ring is connected to the frame body through the spring damping box. The guide wheels are distributed around the frame body. The frame body is matched with the guide steel casing through the guide wheels, and the frame body is connected to the lower steel wire rope through the upper hanging point.

2. The rectangular pile impact hole anti-twist device according to claim 1, characterized in that: Several sleeves are evenly spaced on the outside of the lower steel wire rope along the length direction of the lower steel wire rope, and the lower steel wire rope is connected to the sleeve through a fastening connector. A pivot seat is provided at one end of the sleeve, and a pivot is installed on the pivot seat. A pivot hole corresponding to the pivot is provided at the other end of the sleeve, and an elastic buffer assembly is installed between two adjacent sleeves.

3. The rectangular pile impact hole anti-twist device according to claim 2, characterized in that: The pivots of two adjacent groups of sleeves are arranged alternately in the circumferential direction of the sleeves.

4. The rectangular pile impact hole anti-twist device according to claim 3, characterized in that: The elastic buffer assembly includes a spring, a support plate, a spring wave plate, and screws. The spring wave plate is installed in the interval between two adjacent sleeves. Support plates are fixed at both ends of the spring wave plate. The support plate is connected to the sleeve by screws. The two ends of the spring are respectively connected to the two sleeves; the crests and troughs of the spring wave plate are respectively abutted against the end faces of the two adjacent sleeves.

5. The rectangular pile impact hole anti-twist device according to claim 4, characterized in that: The sleeve comprises a front sleeve, a rear sleeve and a flexible sleeve which are coaxially arranged, the pivot and the pivot hole are respectively connected to the front sleeve and the rear sleeve, and two ends of the flexible sleeve are respectively fixedly connected to the front sleeve and the rear sleeve.

6. The rectangular pile impact hole anti-twist device according to claim 2, characterized in that: The sleeve comprises a first semi-cylinder and a second semi-cylinder, one side of the first semi-cylinder is pivotally connected to one side of the second semi-cylinder, and the other side of the first semi-cylinder is detachably connected to the other side of the second semi-cylinder.

7. A rectangular pile impact hole anti-twist device according to any one of claims 2 to 6, characterized in that: The fastening connector includes a first semicircular plate and a second semicircular plate, which are enclosed on the outer side of the lower wire rope, and mounting seats are correspondingly arranged on the first semicircular plate and the second semicircular plate. Through holes are provided on the mounting seat and the sleeve, and a screw is passed through the through hole. The mounting seat and the screw are fixed by a first nut, and the sleeve and the screw are fixed by a second nut.

8. The rectangular pile impact hole anti-twist device according to claim 7, characterized in that: Arc-shaped grooves are formed on the inner sides of the first semicircular plate and the second semicircular plate, and elastic fastening rings are installed in the arc-shaped grooves.

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