Method of using a ring-type hydraulic pile cutting device with adjustable radius

Abstract

The application discloses a kind of radius adjustable ring type hydraulic pile cutting device's use method, can be hoisted by crane radius adjustable ring type hydraulic pile cutting device hoisting and moves to the center position of the concrete bored pile to be cut above, by driving hydraulic cylinder extension cylinder shrinkage cylinder operation drives rotary arm rotation, to make cutting hydraulic cylinder move, adjust the size of cutting radius, make radius adjustable ring type hydraulic pile cutting device adapt to different pile diameter concrete bored pile cutting construction, then by cutting hydraulic cylinder push cutting steel pile cutting pile head, and by crane pile head is lifted away.Therefore, the use method of the radius adjustable ring type hydraulic pile cutting device, can adjust cutting radius as required, so that the cutting device can be applied to different diameter pile head cutting, improve the adaptability of hydraulic pile cutting device, improve the adaptability and construction efficiency of the cutting device.

Description

Technical Field

[0001] This invention relates to a method of using a ring-type hydraulic pile cutting device with adjustable radius, belonging to the field of building construction technology. Background Technology

[0002] Cast-in-place concrete pile foundations are a conventional form of foundation reinforcement. To ensure the quality of the pile foundations and their effective connection with other superstructures, it is usually required that the piles be over-poured to a certain height during construction, such as 0.5 to 1 meter. Before constructing other superstructures, the pile head (i.e., the over-poured concrete portion) needs to be removed or cut off. Traditional pile head removal methods typically involve manual removal using tools such as pneumatic picks, followed by hoisting away the pile head with a crane. This method has many drawbacks, including high labor and machinery costs, significant construction safety risks, and low levels of mechanization.

[0003] Currently, some companies have developed simple modular hydraulic pile cutting devices. However, since the pile cutting radius cannot be changed after assembly, they cannot directly handle concrete cast-in-place piles of different diameters at the construction site, which presents significant limitations. Summary of the Invention

[0004] To address the problem of poor adaptability in existing hydraulic pile cutting devices where the pile cutting radius cannot be changed after assembly, this invention provides a method for using a ring-type hydraulic pile cutting device with an adjustable radius. This method allows for adjustment of the pile cutting radius as needed, thereby improving the adaptability of the hydraulic pile cutting device.

[0005] To solve the above technical problems, the present invention includes the following technical solutions:

[0006] A method for using a radius-adjustable ring-type hydraulic pile-cutting device, the radius-adjustable ring-type hydraulic pile-cutting device comprising a hydraulic cylinder support, a pile-cutting hydraulic cylinder, a pile-cutting steel rod, a rotary power hydraulic cylinder, and a rotating arm; the cylinder support comprises an annular upper ring plate and a lower ring plate, the upper and lower ring plates being correspondingly provided with several sets of sliding grooves, each set of sliding grooves being correspondingly provided with a rotation center shaft and a hinge node; each set of sliding grooves is correspondingly provided with a pile-cutting hydraulic cylinder and a pile-cutting steel rod, the outer wall of the pile-cutting hydraulic cylinder being provided with an outer positioning shaft and an inner positioning shaft; the outer positioning shaft is disposed in the sliding groove and can slide along the sliding groove; each pile-cutting hydraulic cylinder is provided with a pile-cutting steel rod at its end, one end of the pile-cutting steel rod being a pointed tip, and the other end being fixedly connected to the end of the telescopic rod of the pile-cutting hydraulic cylinder; the middle part of the rotating arm is pinned to the rotation center shaft, one end of the rotating arm is pinned to the inner positioning shaft, the other end is pinned to one end of the rotary power hydraulic cylinder, and the other end of the rotary power hydraulic cylinder is pinned to the hinge node;

[0007] The method of using the adjustable radius ring-type hydraulic pile cutting device includes the following steps:

[0008] S1. Complete device installation: Hoist the adjustable radius ring hydraulic pile cutting device onto the crane's lifting device using wire ropes or chains, and connect the hydraulic oil pipe to the pile cutting hydraulic cylinder;

[0009] S2. Lifting and Positioning: The adjustable-radius ring-type hydraulic pile cutting device is lifted and moved by a crane to the position directly above the center of the concrete pile to be cut;

[0010] S3. Adjust the pile cutting radius: According to the diameter of the concrete cast-in-place pile to be cut, drive the rotating power hydraulic cylinder, adjust the extension length of the telescopic rod, adjust the angle θ between the rotating arm of the pile cutting hydraulic cylinder and the negative direction of the x-axis, thereby adjusting the position of the pile cutting hydraulic cylinder and the steel rod relative to the center of the disc, and adjust the pile cutting radius according to formula (1).

[0011] The pile cutting radius R0 is expressed as a function of θ as follows:

[0012]

[0013] d0 is the distance from the tip of the pile cutting steel rod to the inner positioning shaft when the pile cutting hydraulic cylinder is fully retracted;

[0014] S4. Lifting to the designated height: The crane lifts and lowers the adjustable-radius ring-type hydraulic pile cutting device to the designated pile cutting height of the concrete pile to be cut, so that the adjustable-radius ring-type hydraulic pile cutting device surrounds the pile head of the concrete pile.

[0015] S5. Pile cutting: The circumferentially arranged hydraulic cylinders push the pile cutting steel rod to symmetrically squeeze the pile concrete, eventually causing the pile concrete to crack radially and penetrate to form a plane, thus cutting off the pile head.

[0016] S6. Pile head removal: The crane lifts the adjustable radius ring-type hydraulic pile cutting device along with the cut pile head to the designated site;

[0017] S7. Pile head storage: Drive the hydraulic cylinder for cutting the pile to retract the cutting steel rod, so that the cutting steel rod is pulled back from under the pile head, and the cut pile head is placed on the site for centralized storage.

[0018] Furthermore, with the center of the hydraulic cylinder support as the center O and the direction from the origin to point A as the positive x-axis, a two-dimensional coordinate system xOy is established in the plane containing the upper surface of the upper ring plate of the hydraulic cylinder support. The centerline of the slide groove needs to satisfy the following conditions:

[0019]

[0020] Wherein, the hinge node is denoted as A, the center point of the inner positioning axis is denoted as B, the center point of the outer positioning axis is denoted as C, the distance between points A and B is denoted as r, the distance between points B and C is denoted as l, and the distance between point O and point A is denoted as l. OAθ is the angle between the rotating arm of the pile cutting hydraulic cylinder and the negative x-axis, and θ0 is the set value.

[0021] Furthermore, the width of the groove is matched with the diameter of the outer positioning shaft of the pile cutting hydraulic cylinder, and a rolling bearing is sleeved on the outer positioning shaft.

[0022] The present invention, by adopting the above technical solution, has the following advantages and positive effects compared with the prior art: The present invention provides a method for using a ring-type hydraulic pile cutting device with an adjustable radius. The device can be hoisted and moved by a crane to a position directly above the center of the concrete pile to be cut. The extension and retraction of the driving hydraulic cylinder drives the rotating arm to rotate, thereby moving the pile cutting hydraulic cylinder and adjusting the pile cutting radius. This allows the ring-type hydraulic pile cutting device to adapt to the construction of concrete piles with different diameters. Then, the pile head is cut off by pushing the pile cutting steel rod with the pile cutting hydraulic cylinder, and the pile head is lifted away by a crane. Therefore, the present invention provides a method for using a ring-type hydraulic pile cutting device with an adjustable radius, which can adjust the pile cutting radius as needed, improving the adaptability of the hydraulic pile cutting device. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating the usage method of the adjustable-radius ring-type hydraulic pile-cutting device according to an embodiment of the present invention.

[0024] Figure 2 This is a perspective view of an adjustable-radius ring-type hydraulic pile-cutting device according to an embodiment of the present invention;

[0025] Figure 3 This is a top view of an adjustable-radius ring-type hydraulic pile-cutting device according to an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the upper ring plate provided in an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of the hydraulic cylinder for pile cutting and the pile cutting steel rod provided in an embodiment of the present invention;

[0028] Figure 6 This is a schematic diagram of the structure of a rotary power hydraulic cylinder provided in an embodiment of the present invention;

[0029] Figure 7 This is a schematic diagram of the structure of a rotating arm provided in an embodiment of the present invention;

[0030] Figure 8 A schematic diagram of a two-dimensional coordinate system for an adjustable-radius ring-type hydraulic pile-cutting device according to an embodiment of the present invention;

[0031] Figure 9This is a mathematical model of the movement of the hydraulic cylinder for pile cutting, provided in one embodiment of the present invention.

[0032] The numbers in the diagram are as follows:

[0033] 10-Hydraulic cylinder support; 11-Upper ring plate; 12-Lower ring plate; 13-Slide groove; 14-Rotation center shaft; 15-Hinged joint;

[0034] 20 - Hydraulic cylinder for pile cutting; 21 - External positioning shaft; 22 - Internal positioning shaft;

[0035] 30 - Pile cutting steel rod;

[0036] 40 - Rotary hydraulic cylinder; 41 - First lug plate; 42 - Telescopic rod; 43 - Second lug plate;

[0037] 50 - Rotary arm; 51 - Pin; 52 - First positioning shaft hole; 53 - Second positioning shaft hole. Detailed Implementation

[0038] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, further illustrates the usage method of the adjustable-radius ring-type hydraulic pile-cutting device provided by the present invention. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0039] like Figure 1 As shown, this embodiment provides a method for using a ring-type hydraulic pile-cutting device with an adjustable radius, such as... Figures 2 to 7 As shown, the adjustable-radius ring-type hydraulic pile-cutting device includes a hydraulic cylinder support 10, a pile-cutting hydraulic cylinder 20, a pile-cutting steel rod 30, a rotary power hydraulic cylinder 40, and a rotating arm 50. The hydraulic cylinder support 10 includes an upper ring plate 11 and a lower ring plate 12 spaced vertically. The upper ring plate 11 and lower ring plate 12 are respectively provided with 12 sets of sliding grooves 13. The 12 sets of sliding grooves 13 are rotated symmetrically with the centers of the upper ring plate 11 and lower ring plate 12 as their centers of rotation. The rotation center angle is... After each set of slides 13 rotates by the rotation center angle, the original position of the next set of slides 13 before rotation will coincide with the original position of the next set of slides 13 before rotation. Both the upper ring plate 11 and the lower ring plate 12 are annular. The first end of the slide 13 is close to the outer diameter edge of the annulus, and the second end of the slide 13 is close to the inner diameter edge of the annulus. The centerline of the slide 13 is a curve, and the radius of curvature of the curve gradually increases from the first end to the second end. Each set of slides 13 is correspondingly provided with a rotation center shaft 14 and a hinge node 15. The rotation center shaft 14 and the hinge node 15 are located near the inner diameter of the upper ring plate 11 and the lower ring plate 12. The rotation center shaft 14 is used to install the rotating arm 50, and the hinge node 15 is used to install the rotating power hydraulic cylinder 40. Each slide 13 is correspondingly provided with a pile-cutting hydraulic cylinder 20 and a pile-cutting steel chisel 30. The outer wall of the pile-cutting hydraulic cylinder 20 is provided with an outer positioning shaft 21 and an inner positioning shaft 22. The outer positioning shaft 21 is disposed in the slide groove 13 and can slide along the slide groove 13. Each pile-cutting hydraulic cylinder 20 is provided with a pile-cutting steel rod 30 at its end. One end of the pile-cutting steel rod 30 is a pointed tip, and the other end is fixedly connected to the end of the telescopic rod 42 of the pile-cutting hydraulic cylinder 20. The extension operation of the pile-cutting hydraulic cylinder 20 can move the pointed tip of the pile-cutting steel rod towards the center of the hydraulic cylinder support, and the retraction operation of the pile-cutting hydraulic cylinder 20 can move the pointed tip of the pile-cutting steel rod away from the center of the hydraulic cylinder support.

[0040] Combination Figures 2 to 7 As shown, the rotary hydraulic cylinder 40 includes a first lug 41 at one end, a telescopic rod 42 at the other end, and a second lug 43 at the telescopic end of the telescopic rod 42. Both the first lug 41 and the second lug 43 have pin holes. The first lug 41 is pin-connected to the hinge node 15 on the hydraulic cylinder support 10. The rotating arm 50 has a pin 51 at one end and a first positioning shaft hole 52 at the other end. The pin 51 is hinged to the second lug 43 of the rotary hydraulic cylinder 40. The first positioning shaft hole is hinged to the inner positioning shaft 22 of the pile-cutting hydraulic cylinder 20. A second positioning shaft hole 53 is provided between the pin and the first positioning shaft hole, and the second positioning shaft hole 53 is hinged to the rotation center axis 14 of the hydraulic cylinder support 10. The extension and retraction operations of the rotary hydraulic cylinder 40 can drive the rotating arm to rotate around the rotation center axis 14.

[0041] This embodiment provides a method for using a ring-type hydraulic pile cutting device with an adjustable radius, including the following steps:

[0042] S1. Complete device installation: Hoist the adjustable radius ring hydraulic pile cutting device from Example 1 onto the crane's lifting device using wire ropes or chains, and connect the hydraulic oil pipe to the pile cutting hydraulic cylinder 20.

[0043] S2. Lifting and Positioning: The adjustable-radius ring-type hydraulic pile cutting device is lifted and moved by a crane to the position directly above the center of the concrete pile to be cut.

[0044] S3. Adjust the pile cutting radius: Based on the diameter of the concrete pile to be cut, drive the rotating power hydraulic cylinder 40, adjust the extension length of the telescopic rod 42, adjust the angle θ between the rotating arm 50 of the pile cutting hydraulic cylinder 20 and the negative x-axis, thereby adjusting the position of the pile cutting hydraulic cylinder 20 and the steel rod relative to the center of the disc, and adjust the pile cutting radius according to formula (1).

[0045] The pile cutting radius R0 is expressed as a function of θ as follows:

[0046]

[0047] S4. Lifting to the designated height: The crane lifts and lowers the adjustable-radius ring-type hydraulic pile cutting device to the designated pile cutting height of the concrete pile to be cut, so that the adjustable-radius ring-type hydraulic pile cutting device surrounds the pile head of the concrete pile.

[0048] S5. Pile cutting: The circumferentially arranged hydraulic cylinders 20 push the pile cutting steel chisels 30 to symmetrically squeeze the pile concrete, eventually causing the pile concrete to crack radially and penetrate to form a plane, thus achieving the cutting off of the pile head.

[0049] S6. Pile head removal: The crane lifts the adjustable-radius ring-type hydraulic pile cutting device, along with the cut pile head, to the designated site.

[0050] S7. Pile head storage: Drive the hydraulic cylinder 20 to retract the cutting steel rod 30, so that the cutting steel rod 30 is retracted from under the pile head, and the cut pile head is placed on the site for centralized storage.

[0051] In one specific embodiment, the inner positioning shaft 22 of the pile-cutting hydraulic cylinder 20 rotates towards or away from the center of the hydraulic cylinder support 10 as the rotary power hydraulic cylinder 40 extends or retracts, and the outer positioning shaft 21 slides accordingly within the slide groove 13. To ensure that the tip of the pile-cutting steel rod 30 always points towards the center of the hydraulic cylinder support 10, combined with... Figures 1 to 9 As shown, with the center of the hydraulic cylinder support 10 as the center O, and the direction from the origin to the rotation center A of the pile-cutting hydraulic cylinder 20 as the positive x-axis, a two-dimensional coordinate system xOy is established in the plane containing the upper surface of the upper ring plate 11 of the hydraulic cylinder support 10. The centerline of the slide groove 13 needs to satisfy the following conditions:

[0052]

[0053] In this diagram, hinge node 15 is denoted as A, the center point of the inner positioning axis 22 is denoted as B, the center point of the outer positioning axis 21 is denoted as C, the distance between points A and B is denoted as r, the distance between points B and C is denoted as l, and the distance between point O and point A is denoted as l. OA θ is the angle between the rotating arm 50 of the pile cutting hydraulic cylinder 20 and the negative x-axis, and θ0 is the set value.

[0054] The proof of formula (2) is as follows:

[0055] The equation for the trajectory B(x0,y0) of the end of the rotating arm 50 of the hydraulic cylinder 20 for pile cutting is:

[0056] (x0-l OA ) 2 +y0 2 =r 2 (3)

[0057] If the angle between the rotating arm 50 of the hydraulic cylinder 20 for pile cutting and the negative x-axis is θ, then the trajectory equation of B(x0,y0) can be written as a parametric equation:

[0058]

[0059] To ensure that the hydraulic cylinder 20 for pile cutting points axially towards the center of the concrete pile, the central section of the hydraulic cylinder 20 is designed to always pass through the origin O. Therefore, points O, B, and C are collinear. The equation of the locus of point C(x,y) is:

[0060]

[0061] Since point C is the center of the outer positioning axis 21 of the hydraulic cylinder 20 for pile cutting, in order to ensure the uniqueness of the trajectory, x-x0>0;

[0062] make Substituting this into formula (5), we get:

[0063]

[0064] Substituting formula (4) into formula (6) yields the following:

[0065]

[0066] Formula (2) can be obtained from formula (7).

[0067] The proof of formula (1) is as follows:

[0068] Since the central axis of the hydraulic cylinder 20 for pile cutting and the steel chisel always passes through the center point of the disc, therefore:

[0069] R0 = l OB -d0; (8)

[0070] From the meaning of d0, it can be seen that the distance from the tip of the pile cutting steel rod 30 to the inner positioning shaft 22 is a constant value after processing; from the trajectory equation of B(x0,y0) in formula (2), the distance l between the origin O and point B can be obtained. OB for:

[0071]

[0072] Substituting equation (9) into equation (8) yields equation (1).

[0073] It should be noted that the principle of adjusting the pile cutting radius of the adjustable ring-type hydraulic pile cutting device provided in this embodiment is as follows: the extended cylinder operation of the rotary power hydraulic cylinder 40 pushes the pin of the rotary arm 50, causing the rotary arm 50 to rotate counterclockwise around the rotation center axis 14, causing the pile cutting hydraulic cylinder 20 to rotate around the center of the hydraulic cylinder support 10 and move towards the center of the hydraulic cylinder support 10. The outer positioning shaft 21 of the pile cutting hydraulic cylinder 20 slides from the first end to the second end in the slide groove 13, and the pile cutting radius of the pile cutting steel rod 30 gradually decreases. The retracted cylinder operation of the rotary power hydraulic cylinder 40 can pull the pin of the rotary arm 50, causing the rotary arm 50 to rotate clockwise around the rotation center axis 14, causing the pile cutting hydraulic cylinder 20 to rotate around the center of the hydraulic cylinder support 10 and move away from the center of the hydraulic cylinder support 10. The outer positioning shaft 21 of the pile cutting hydraulic cylinder 20 slides from the second end to the first end in the slide groove 13, and the pile cutting radius of the pile cutting steel rod 30 gradually increases. The so-called pile cutting radius of the pile cutting steel rod 30 refers to the distance from the tip of the pile cutting steel rod 30 to the center of the hydraulic cylinder support 10 when the pile cutting hydraulic cylinder 20 is in the retracted state.

[0074] Traditional pile-cutting devices have their hydraulic cylinders fixed on connecting plates or cylinder supports, meaning their positions are fixed and cannot be adjusted. The movement of the cutting rod is only achieved through the extension and retraction of the hydraulic cylinder. Because the extension and retraction stroke of the hydraulic cylinder 20 is limited, traditional pile-cutting devices have poor versatility, requiring replacement with devices that match different pile diameters. This embodiment provides an adjustable-radius ring-type hydraulic pile-cutting device. Each set of hydraulic cylinders on the hydraulic cylinder support 10 is equipped with a corresponding groove 13, a driving rotary hydraulic cylinder 40, and a rotating arm 50. The outer positioning shaft 21 of the hydraulic cylinder 20 is located in the groove 13. The extension or retraction of the rotary hydraulic cylinder 40 drives the rotating arm 50, causing the hydraulic cylinder to move towards or away from the center of the hydraulic cylinder support 10. This adjusts the cutting radius of the cutting rod 30, allowing the device to adapt to a wider range of pile diameters and improving its versatility.

[0075] In one specific embodiment, the width of the groove 13 matches the diameter of the outer positioning shaft 21 of the pile cutting hydraulic cylinder 20. To facilitate the sliding of the outer positioning shaft 21 within the groove 13, a rolling bearing can be fitted onto the outer positioning shaft 21. This arrangement reduces sliding resistance and improves the smoothness of the outer positioning shaft's movement.

[0076] In one specific embodiment, after the outer positioning shaft 21 stops sliding, a positioning element is provided on the outer positioning shaft 21 to fix the outer positioning shaft 21 in the slide groove 13. For example, the positioning element can be a nut sleeved on the positioning shaft and threadedly connected to the positioning shaft. This arrangement allows the pile cutting hydraulic cylinder to be fixed on the hydraulic cylinder support, and the pile cutting hydraulic cylinder can provide a reliable reaction force during the pile cutting process.

[0077] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1.A method for using a radius-adjustable ring-type hydraulic pile cutting device, characterized in that the radius-adjustable ring-type hydraulic pile cutting device comprises a hydraulic cylinder support, a pile cutting hydraulic cylinder, a pile cutting steel drill, a rotary power hydraulic cylinder and a rotary arm; the hydraulic cylinder support comprises a circular upper ring plate and a circular lower ring plate, a plurality of groups of sliding grooves are correspondingly arranged on the upper ring plate and the lower ring plate, each group of sliding grooves is correspondingly provided with a rotary center shaft and a hinged node, each group of sliding grooves is correspondingly provided with a pile cutting hydraulic cylinder and a pile cutting steel drill, an outer positioning shaft and an inner positioning shaft are arranged on the outer wall of the pile cutting hydraulic cylinder, the outer positioning shaft is arranged in the sliding groove and can slide along the sliding groove, the end of each pile cutting hydraulic cylinder is provided with a pile cutting steel drill, one end of the pile cutting steel drill is a pointed end, and the other end is fixedly connected with the end of the telescopic rod of the pile cutting hydraulic cylinder, the middle part of the rotary arm is pinned to the rotary center shaft, one end of the rotary arm is pinned to the inner positioning shaft, and the other end is pinned to one end of the rotary power hydraulic cylinder, the other end of the rotary power hydraulic cylinder is pinned to the hinged node; the method for using the radius-adjustable ring-type hydraulic pile cutting device comprises the following steps: S1.completing device installation: the radius-adjustable ring-type hydraulic pile cutting device is hoisted on the lifting tool of a crane through a steel wire rope or an iron chain, and a hydraulic oil pipe is connected with the pile cutting hydraulic cylinder; S2.hoisting and moving into position: the radius-adjustable ring-type hydraulic pile cutting device is hoisted and moved to the center position of a to-be-cut concrete bored pile by the crane; θ θ S3. Adjusting the pile cutting radius: Based on the diameter of the concrete-filled pile to be cut, drive the rotary hydraulic cylinder to adjust the extension length of the cylinder's telescopic rod. With the center of the hydraulic cylinder support as the origin O, and the direction from the origin to point A as... x Establish a two-dimensional coordinate system in the plane containing the upper surface of the upper ring plate of the hydraulic cylinder support along the positive axis. x O y Adjust the rotating arm of the pile cutting hydraulic cylinder and x Angle in the negative direction of the axis S4.hoisting to a specified height: the radius-adjustable ring-type hydraulic pile cutting device is hoisted and lowered to a specified pile cutting height of the to-be-cut concrete bored pile by the crane, so that the radius-adjustable ring-type hydraulic pile cutting device surrounds the pile head of the concrete bored pile; This allows for the adjustment of the position of the hydraulic cylinder and the steel chisel relative to the center of the hydraulic cylinder support, and the adjustment of the pile cutting radius according to formula (1). Chopping radius R 0 is represented as S5.pile cutting: the symmetrically extruded pile body concrete of the pile cutting steel drill is pushed by the circumferentially arranged pile cutting hydraulic cylinder, finally causing the pile body concrete to break along the radial direction and form a plane, so that the pile head is cut off; The functional relationship is: ， （1） The distance from the tip of the cutting steel drill to the inner positioning shaft when the cutting hydraulic oil cylinder is completely retracted. S6.pile head hoisting: the radius-adjustable ring-type hydraulic pile cutting device together with the cut-off pile head is hoisted to a specified site by the crane; S7.pile head storage: the pile cutting steel drill is retracted by driving the pile cutting hydraulic cylinder, so that the pile cutting steel drill is retracted from the pile head, and the cut-off pile head is placed on the site for storage. 2.The method for using the radius-adjustable ring-type hydraulic pile cutting device according to claim 1, characterized in that θ θ The center of the hydraulic cylinder support is taken as the origin O, and the direction from the origin to point A is taken as the positive direction of the axis x A two-dimensional coordinate system is established in the plane of the upper surface of the upper ring plate of the hydraulic cylinder support x O y The center line of the sliding groove needs to satisfy the following conditions: ，（2） Wherein, the hinge node is denoted as A, the center point of the inner positioning axis is denoted as B, the center point of the outer positioning axis is denoted as C, and the distance between points A and B is denoted as . r The distance between point B and point C is denoted as . l The distance between point O and point A is denoted as . l OA , 3.The method for using the radius-adjustable ring-type hydraulic pile cutting device according to claim 1, characterized in that the slot width of the sliding groove matches the diameter of the outer positioning shaft of the pile cutting hydraulic cylinder, and a rolling bearing is arranged on the outer positioning shaft. For the hydraulic cylinder rotating arm of pile cutting and x The angle in the negative direction of the axis, ​ 0 Setting value. ​ ​

Images