A special lifting tool and loading / unloading process for hoisting large pipe pile pipe sections

Abstract

The present invention provides a special lifting tool and loading and unloading process for hoisting large pipe pile pipe sections, which relates to the technical field of pipe pile pipe section hoisting devices and includes a boom body. The boom body has a C-shaped opening structure with elongated upper and lower ends; pulling rods that move synchronously towards or away from each other are provided at both ends of the leveling ball slide rod. A pair of flexible stabilizing mechanisms are symmetrically installed on both sides of the boom body respectively. A compensation telescopic oil cylinder is also arranged inside the boom body. The pulling telescopic oil rod, the compensation telescopic oil cylinder, the flexible stabilizing mechanism and the active telescopic oil cylinder are interconnected through an oil circuit. Before the pipe body is suspended, the boom body is moved to a counterweight balanced position through the traction of the pulling rods in the present invention, and effective internal support for pipe body structures with different thicknesses is achieved through the expansion and contraction of the rubber telescopic rod, thereby ensuring the overall gravity balance of the suspension mechanism and greatly ensuring the safety of the suspension process.

Description

Technical Field

[0001] The present invention relates to the technical field of pipe pile section lifting devices, and specifically to a special lifting tool and loading / unloading process for lifting large pipe pile sections. Background Art

[0002] In the prior art, a large-diameter reinforced concrete pipe body lifting device with the publication number of "CN221565480U" for improving lifting and assembly stability includes: a U-shaped steel frame body having a hoisting clamping groove with an opening facing the side; a plurality of groups of hoisting seat structures are provided, and the plurality of groups of hoisting seat structures are respectively fixedly assembled on the top of the U-shaped steel frame body; an extension rod is rotatably assembled at one end on one side of the U-shaped steel frame body; a fixed frame clamp is rotatably assembled and connected to the other end of the extension rod, and the fixed frame clamp has a clamping end for detachably clamping the pipe body. It solves the technical problems of low efficiency, affecting assembly quality and high safety risks in the prior art when hoisting and assembling a large-diameter reinforced concrete pipe body by tying with a lifting rope.

[0003] However, the above device still has obvious defects during use: the above device requires manual pulling and connection, the fixing process is relatively cumbersome, and due to the differences in the length and thickness of the pipe body, the above device cannot be adjusted specifically according to the length and thickness of the pipe body, which is not conducive to ensuring stability during suspension, and production safety accidents may occur due to unbalanced stress of the suspension mechanism. Summary of the Invention

[0004] The purpose of the present invention is to provide a special lifting tool and loading / unloading process for lifting large pipe pile sections to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A special lifting tool for lifting large pipe pile sections includes a boom body, and the boom body has a C-shaped opening structure with the upper and lower ends elongated.

[0007] A leveling ball screw is installed in a lifting manner between the upper and lower openings of the boom body. The leveling ball screw is inserted into the pipe body during the hoisting of the pipe body. The upper surface of the leveling ball screw is arranged in a rectangular array with sliding balls. Pulling rods that move synchronously towards or away from each other are provided at both ends of the leveling ball screw. By the opposite movement of the pulling rods on both sides, the inserted pipe body is pushed to the counterweight balance position. The pulling rods on both sides perform translational sliding during the telescopic process of the pulling telescopic oil rod.

[0008] A pair of flexible stabilizing mechanisms are symmetrically installed on both sides of the boom body. Each flexible stabilizing mechanism includes an oil cylinder sleeve and a rubber telescopic rod. The rubber telescopic rods of the flexible stabilizing mechanisms on both sides perform synchronous telescopic movements within the oil cylinder sleeves, and the inner wall of the pipe is abutted by the rubber telescopic rods to further ensure the stability of the pipe during hoisting.

[0009] The bottom of the leveling ball slide rod is fixedly connected to the telescopic arms of several active telescopic oil cylinders. A compensation telescopic oil cylinder is also arranged inside the boom body. The traction telescopic oil rod, the compensation telescopic oil cylinder, the flexible stabilizing mechanism, and the active telescopic oil cylinder are interconnected through an oil circuit. During the transfer of oil, the corresponding mechanisms are pushed to perform telescopic movements. Among them, without external force, the oil in the traction telescopic oil rod, the compensation telescopic oil cylinder, and the flexible stabilizing mechanism enters the active telescopic oil cylinder to push the leveling ball slide rod upward. When the leveling ball slide rod descends under the action of the pipe weight, the oil flows out of the active telescopic oil cylinder and flows in the order of the traction telescopic oil rod first, then the flexible stabilizing mechanism, and finally the compensation telescopic oil cylinder.

[0010] Preferably, the active telescopic oil cylinder, the traction telescopic oil rod, and the compensation telescopic oil cylinder all include a cylinder body, a piston telescopic arm, and a compression spring. A compression spring is also arranged inside the flexible stabilizing mechanism. By adjusting the stiffness coefficients of the compression springs in different mechanisms, the sequence of their actions can be adjusted.

[0011] Preferably, the boom body includes a variable cross-section empty box lower boom, a circular arc empty box end boom, and a variable cross-section empty box upper boom. The variable cross-section empty box lower boom, the circular arc empty box end boom, and the variable cross-section empty box upper boom are welded and fixed. The length of the variable cross-section empty box lower boom is longer than that of the variable cross-section empty box upper boom.

[0012] Preferably, a pair of hooks are fixedly installed on the variable cross-section empty box upper boom.

[0013] Preferably, an embedding groove for the leveling ball slide rod to be embedded is opened in the middle of the variable cross-section empty box lower boom. The leveling ball slide rod slides horizontally toward the side close to the embedding groove under the action of the pipe weight. Flexible pads are installed on both the variable cross-section empty box lower boom and the circular arc empty box end arm on both sides of the embedding groove. After the leveling ball slide rod descends to the limit position, the upper surface of the leveling ball slide rod is lower than the upper surface of the flexible pads, so that the inner wall of the pipe abuts against the flexible pads.

[0014] Preferably, pressure sensors are evenly distributed at the bottom of the flexible pads to detect the pressure distribution conditions of each part of the flexible pads.

[0015] A loading and unloading process for hoisting large pipe pile pipe joints, using the above-mentioned special lifting tool for hoisting large pipe pile pipe joints, includes the following steps:

[0016] Step 1: Use a gantry crane to lift the boom body to the pipe to be hoisted, insert the variable cross-section empty box lower boom into the pipe, and then use the gantry crane to drive the boom body to slowly rise.

[0017] Step 2: During the rising process of the boom body, the leveling ball slide bar first abuts against the inside of the pipe. As the boom body continues to rise, the leveling ball slide bar is pushed downward under the action of the pipe's own weight. At this time, the active telescopic oil cylinder is compressed, and the oil first enters the traction telescopic rod.

[0018] Step 3: When the oil first enters the traction telescopic rod, it pushes the traction rods at both ends of the leveling ball slide bar to move towards each other. As the traction rods move towards each other synchronously, the boom body makes a follow-up adjustment so that the pipe moves to the counterweight balance position. At this time, the traction rods at both ends abut against both ends of the pipe. After this process is completed, the leveling ball slide bar is still in the descending process.

[0019] Step 4: After the traction rods clamp and limit the pipe, as the leveling ball slide bar continues to descend, the oil enters the flexible stabilizing mechanism. The oil pushes the rubber telescopic rod to move away from the oil cylinder sleeve and abut against the inner wall of the pipe, thus further limiting the pipe.

[0020] Step 5: As the leveling ball slide bar continues to descend, the internal oil finally enters the compensation telescopic oil cylinder, thus completing the transfer of the oil inside the leveling ball slide bar. At this time, the leveling ball slide bar enters the embedding groove, the pipe contacts the flexible cushion block, and is lifted as the boom body rises.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] The present invention uses the self-weight of the pipe to drive the corresponding mechanism to work. Before the pipe is suspended, the boom body is moved to the counterweight balance position through the traction of the traction rods, and the effective internal support for pipe structures of different thicknesses is achieved through the expansion and contraction of the rubber telescopic rod, thus ensuring the overall gravity balance of the suspension mechanism. Combining the internal support of the rubber telescopic rod effectively prevents the pipe from tipping and sliding during the hoisting process, greatly ensuring the safety of the suspension process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a three-dimensional schematic diagram of the overall structure of the present invention;

[0024] Figure 2 is a three-dimensional schematic diagram of the connection structure of the leveling ball slide bar of the present invention;

[0025] Figure 3 is a schematic cross-sectional view in the side view state of the present invention;

[0026] Figure 4Schematic diagram of the oil circuit connection state of the active telescopic oil cylinder of the present invention;

[0027] Figure 5 Schematic diagram of the oil circuit connection structure between the traction telescopic oil rod and the active telescopic oil cylinder of the present invention.

[0028] In the figure: 1 boom body, 2 leveling ball slide bar, 3 sliding ball, 4 traction lever, 5 traction telescopic oil rod, 6 oil cylinder sleeve, 7 rubber telescopic rod, 8 active telescopic oil cylinder, 9 compensation telescopic oil cylinder, 10 cylinder block, 11 piston telescopic arm, 12 compression spring, 13 variable cross-section empty box lower boom, 14 arc-shaped empty box end arm, 15 variable cross-section empty box upper boom, 16 hook, 17 embedding groove, 18 flexible cushion block. Specific implementation manner

[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0030] Please refer to Figures 1 - 5 , the present invention provides a technical solution:

[0031] Embodiment 1:

[0032] A special lifting tool for hoisting large pipe pile sections, including a boom body 1, and the boom body 1 has a C-shaped opening structure with elongated upper and lower ends;

[0033] A leveling ball slide bar 2 is installed in a lifting manner between the upper and lower openings of the boom body 1. The leveling ball slide bar 2 is inserted into the pipe body during the pipe body hoisting process. The upper surface of the leveling ball slide bar 2 is arranged in a rectangular array with sliding balls 3. The two ends of the leveling ball slide bar 2 are provided with traction levers 4 that move synchronously towards or away from each other. By the opposite movement of the two traction levers 4 on both sides, the inserted pipe body is pushed to the counterweight balance position, and the two traction levers 4 on both sides perform translational sliding during the telescopic process of the traction telescopic oil rod 5;

[0034] A pair of flexible stabilizing mechanisms are symmetrically installed on both sides of the boom body 1. The flexible stabilizing mechanism includes an oil cylinder sleeve 6 and a rubber telescopic rod 7. The rubber telescopic rods 7 on both sides of the flexible stabilizing mechanism perform synchronous telescopic movement in the oil cylinder sleeve 6, and the inner wall of the pipe body is abutted by the rubber telescopic rods 7 to further ensure the stability during the pipe body hoisting process;

[0035] The bottom of the leveling ball slide bar 2 is fixedly connected to the telescopic arms of several active telescopic oil cylinders 8. A compensating telescopic oil cylinder 9 is also arranged inside the boom body 1. The pulling telescopic oil rod 5, the compensating telescopic oil cylinder 9, the flexible stabilizing mechanism and the active telescopic oil cylinder 8 are interconnected through an oil circuit. The oil fluid pushes the corresponding mechanisms to perform telescopic movements during the transfer process. Among them, without external force, the oil fluid in the pulling telescopic oil rod 5, the compensating telescopic oil cylinder 9 and the flexible stabilizing mechanism enters the active telescopic oil cylinder 8 to push the leveling ball slide bar 2 to move upward. When the leveling ball slide bar 2 descends under the action of the pipe weight, the oil fluid flows out of the active telescopic oil cylinder 8 and flows in the order of the pulling telescopic oil rod 5 first, then the flexible stabilizing mechanism, and finally the compensating telescopic oil cylinder 9.

[0036] In this embodiment, the boom body 1 is the main structure, which is a C-shaped opening structure with the upper and lower ends elongated, including a variable cross-section hollow lower boom 13, a circular arc hollow end boom 14 and a variable cross-section hollow upper boom 15. The variable cross-section hollow lower boom 13, the circular arc hollow end boom 14 and the variable cross-section hollow upper boom 15 are welded and fixed. A pair of hooks 16 are fixedly installed on the variable cross-section hollow upper boom 15. The entire boom body 1 is towed by suspending the hooks 16 through a hoisting steel cable. The length of the variable cross-section hollow lower boom 13 is longer than that of the variable cross-section hollow upper boom 15. Among them, a leveling ball slide bar 2 is installed in a lifting manner between the upper and lower openings of the boom body 1. The upper surface of the leveling ball slide bar 2 is arranged with sliding balls 3 in an array, so that the pipe body can slide horizontally with the leveling ball slide bar 2 more easily. The two ends of the leveling ball slide bar 2 are provided with pulling rods 4 that move synchronously towards or away from each other. The pulling rods 4 perform translational sliding during the telescopic process of the pulling telescopic oil rod 5. The bottom of the leveling ball slide bar 2 is fixedly connected to the telescopic arms of several active telescopic oil cylinders 8. When the leveling ball slide bar 2 descends under the action of the pipe weight, the oil fluid flows out of the active telescopic oil cylinder 8 and first enters the pulling telescopic oil rod 5. Refer to the attached Figure 5, there are grooved structures on both the upper and lower sides of the active telescopic oil cylinder 8. The telescopic arm of the active telescopic oil cylinder 8 is fixedly connected to the leveling ball slide rod 2. By arranging an oil circuit in the leveling ball slide rod 2, the hydraulic oil in the active telescopic oil cylinder 8 preferentially enters the pulling telescopic oil rod 5 from above through the leveling ball slide rod 2 when being pumped out. After the pulling telescopic oil rod 5 is filled with oil, its rod body contracts inward, and at this time, the pulling rods 4 on both sides are driven to move towards each other synchronously. Due to the large self-weight of the pipe body, it is difficult to make it move only by the push of the pulling rods 4. However, the boom body 1 is in a suspended state. Therefore, when the pulling rods 4 move towards each other and abut against both ends of the pipe body, they will push the boom body 1 to adjust its position, so that it moves to the position of gravity balance. At this time, suspending the pipe body again can ensure the uniformity of the gravity distribution, and can effectively prevent the production safety accident of the pipe body falling off during the subsequent suspension process. At the same time, the bottom of the active telescopic oil cylinder 8 is connected to the flexible stabilizing mechanism and the compensating telescopic oil cylinder 9 through an oil circuit opened in the boom body 1. The structure of the flexible stabilizing mechanism is similar to that of the telescopic oil cylinder. The rubber telescopic rod 7 moves telescopically in the oil cylinder sleeve 6, so as to further prevent the pipe body from sliding during the suspension process by the abutment of the rubber telescopic rod 7 against the inner wall of the pipe body. The telescopic process of the rubber telescopic rod 7 is also realized through the transfer of hydraulic oil. The leveling ball slide rod 2 descends under the self-weight of the pipe body. Since the pulling rods 4 on both sides have limited and fixed both ends of the pipe body, the hydraulic oil can no longer enter the pulling telescopic oil rod 5 at this time. As the active telescopic oil cylinder 8 continues to compress, the hydraulic oil enters the oil cylinder sleeve 6 and pushes the rubber telescopic rod 7 to extend outward, so as to complete the abutment against the inner wall of the pipe body. After the abutment is completed, as the leveling ball slide rod 2 continues to descend, the excess hydraulic oil finally enters the compensating telescopic oil cylinder 9 for storage. It should be noted that the size parameters of the active telescopic oil cylinder 8 in the figure are small, and it is only for illustration. During the design process, by setting the size and quantity of the active telescopic oil cylinder 8, the hydraulic oil with a volume sufficient to realize the above actions can be filled inside it, so as to ensure the normal progress of the above operations. Since the boom body 1 needs to suspend pipe bodies with different lengths and thicknesses, the telescopic ranges of the pulling rods 4 and the rubber telescopic rod 7 are not fixed during each suspension process. Therefore, the setting of the compensating telescopic oil cylinder 9 can store the excess hydraulic oil. Among them, the active telescopic oil cylinder 8, the pulling telescopic oil rod 5, and the compensating telescopic oil cylinder 9 all include a cylinder body 10, a piston telescopic arm 11, and a compression spring 12. The compression spring 12 is also arranged inside the flexible stabilizing mechanism. This kind of telescopic mechanism driven by hydraulic oil is relatively common in the prior art and will not be elaborated in detail here. In order to ensure the sequence of operation of the above device, compression springs 12 with different stiffness coefficients are arranged in the active telescopic oil cylinder 8, the pulling telescopic oil rod 5, the compensating telescopic oil cylinder 9, and the flexible stabilizing mechanism. The pulling telescopic oil rod 5 that moves first is provided with the compression spring 12 with the lowest stiffness coefficient, while the compensating telescopic oil cylinder 9 is provided with the compression spring 12 with the largest stiffness coefficient.Thus enabling the smooth progress of different structural actions one after another.

[0037] Embodiment 2:

[0038] An embedded groove 17 is provided inside the variable cross-section empty box lower boom 13. During the descending process, the leveling ball slide rod 2 enters the embedded groove 17, and the pipe body finally rests on the flexible cushion block 18, thereby ensuring the stability during the suspension process.

[0039] An embedded groove 17 for embedding the leveling ball slide rod 2 is provided in the middle of the variable cross-section empty box lower boom 13. Under the action of the gravity of the pipe body, the leveling ball slide rod 2 translates and slides toward the side close to the embedded groove 17. Flexible cushion blocks 18 are installed on both the variable cross-section empty box lower boom 13 and the arc-shaped empty box end arm 14 on both sides of the embedded groove 17. After the leveling ball slide rod 2 descends to the limit position, its upper surface is lower than the upper surface of the flexible cushion block 18, so that the inner wall of the pipe body abuts against the flexible cushion block 18.

[0040] Embodiment 3:

[0041] Pressure sensors are evenly distributed at the bottom of the flexible cushion block 18, and the pressure distribution conditions of each part of the flexible cushion block 18 are detected through the pressure sensors.

[0042] In this embodiment, through the setting of the pressure sensors, the pressure distribution conditions at each position can be monitored in real time during the suspension process of the pipe body, which is beneficial to timely discovering the uneven gravity distribution condition of the pipe body and further ensuring the safety during the suspension process.

[0043] A loading and unloading process for hoisting large pipe pile sections, using the above-mentioned special lifting tool for hoisting large pipe pile sections, includes the following steps:

[0044] Step 1: Use a gantry crane to lift the boom body 1 to the position of the pipe body to be hoisted, insert the variable cross-section empty box lower boom 13 into the pipe body, and then drive the boom body 1 to slowly rise through the gantry crane;

[0045] Step 2: During the rising process of the boom body 1, the leveling ball slide rod 2 first abuts against the inside of the pipe body. As the boom body 1 continues to rise, the leveling ball slide rod 2 is pushed downward under the action of the self-weight of the pipe body. At this time, the active telescopic oil cylinder 8 is compressed, and the oil first enters the pulling telescopic oil rod 5;

[0046] Step 3: When the oil first enters the pulling telescopic oil rod 5, it pushes the pulling rods 4 at both ends of the leveling ball slide rod 2 to move toward each other. As the pulling rods 4 move synchronously toward each other, the boom body 1 makes a follow-up adjustment so that the pipe body moves to the counterweight balance position. At this time, the pulling rods 4 at both ends abut against both ends of the pipe body. After this process is completed, the leveling ball slide rod 2 is still in the descending process;

[0047] Step Four: After the pulling lever 4 clamps and positions the pipe body, as the leveling ball slide rod 2 continues to descend, the oil enters the flexible stabilizing mechanism. The oil pushes the rubber telescopic rod 7 to move away from the oil cylinder sleeve 6 and thus abuts against the inner wall of the pipe body, thereby completing the further positioning of the pipe body.

[0048] Step Five: As the leveling ball slide rod 2 continues to descend, the internal oil finally enters the compensation telescopic oil cylinder 9, thereby completing the transfer of the oil inside the leveling ball slide rod 2. At this time, the leveling ball slide rod 2 enters the embedding groove, the pipe body contacts the flexible cushion block 18, and is lifted as the lifting arm body 1 rises.

[0049] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A special lifting device for lifting large pipe pile sections, comprising a lifting arm body, wherein the lifting arm body is a C-shaped opening structure with elongated upper and lower ends; characterized in that: A leveling ball slide is installed between the upper and lower openings of the boom body in a lifting manner. The leveling ball slide is inserted into the tube body during the lifting process of the tube body. Sliding balls are arranged in a rectangular array on the upper surface of the leveling ball slide. Pulling levers that move toward or away from each other synchronously are provided at both ends of the leveling ball slide. The pulling levers on both sides move toward each other to push the inserted tube body to the counterweight balance position. The pulling levers on both sides slide in translation during the extension and retraction process of the pulling telescopic oil rod. A pair of flexible stabilizing mechanisms are symmetrically installed on both sides of the boom body, and the flexible stabilizing mechanisms include a cylinder sleeve and a rubber telescopic rod. The rubber telescopic rods of the flexible stabilizing mechanisms on both sides perform telescopic movements synchronously in the cylinder sleeve, and the rubber telescopic rods abut against the inner wall of the pipe body to further ensure the stability of the pipe body during lifting; The bottom of the leveling ball slide is fixedly connected to the telescopic arms of several active telescopic oil cylinders. A compensating telescopic oil cylinder is also arranged in the boom body. The pulling telescopic oil rod, the compensating telescopic oil cylinder, the flexible stabilizing mechanism and the active telescopic oil cylinder are interconnected through an oil circuit. The oil pushes the corresponding mechanism to perform telescopic movement during the transfer process. In the absence of external force, the oil in the pulling telescopic oil rod, the compensating telescopic oil cylinder and the flexible stabilizing mechanism enters the active telescopic oil cylinder to push the leveling ball slide to move upward. When the leveling ball slide descends under the weight of the pipe body, the oil flows out of the active telescopic oil cylinder and flows in a manner of first pulling the telescopic oil rod, then the flexible stabilizing mechanism and finally the compensating telescopic oil cylinder. The active telescopic cylinder, pulling telescopic rod and compensating telescopic cylinder all include a cylinder body, a piston telescopic arm and an extrusion spring. The flexible stabilizing mechanism is also provided with an extrusion spring. The sequence of their actions can be adjusted by adjusting the stiffness coefficients of the extrusion springs in different mechanisms.

2. A special lifting device for lifting large pipe pile sections according to claim 1, characterized in that: The boom body includes a variable-section empty box lower boom, an arc-shaped empty box end boom and a variable-section empty box upper boom. The variable-section empty box lower boom, the arc-shaped empty box end boom and the variable-section empty box upper boom are welded and fixed to each other. The length of the variable-section empty box lower boom is longer than that of the variable-section empty box upper boom.

3. A special lifting device for lifting large pipe pile sections according to claim 2, characterized in that: A pair of hooks are also fixedly mounted on the upper boom of the variable-section empty box.

4. A special lifting device for lifting large pipe pile sections according to claim 3, characterized in that: An embedding groove for embedding a leveling ball slide is provided in the middle of the lower hanging arm of the variable-section empty box. The leveling ball slide slides horizontally toward the side close to the embedding groove under the action of the weight of the tube body. Flexible pads are installed on the lower hanging arm of the variable-section empty box and the arc-shaped empty box end arms on both sides of the embedding groove. After the leveling ball slide is lowered to the extreme position, its upper surface is lower than the upper surface of the flexible pad, so that the inner wall of the tube body is in contact with the flexible pad.

5. A special lifting device for lifting large pipe pile sections according to claim 4, characterized in that: Pressure sensors are evenly distributed on the bottom of the flexible pad, and the pressure distribution conditions of various parts of the flexible pad are detected by the pressure sensors.

6. A loading and unloading process for lifting large pipe pile sections, using the special lifting device for lifting large pipe pile sections according to claim 4 or 5, characterized in that: The following steps are involved: Step 1: Use the crane to lift the boom body to the pipe body to be lifted, insert the lower boom of the variable cross-section empty box into the pipe body, and then drive the boom body to rise slowly through the crane; Step 2: During the rising process of the boom body, the leveling ball slide bar first abuts against the inside of the tube body. As the boom body continues to rise, the leveling ball slide bar is pushed downward under the weight of the tube body. At this time, the active telescopic oil cylinder is compressed, and the oil first enters the pulling telescopic oil rod; Step 3: When the oil first enters the pulling and telescopic oil rod, it pushes the pulling levers at both ends of the leveling ball slide rod to move toward each other. As the pulling levers move toward each other synchronously, the boom body performs follow-up adjustment so that the tube body moves to the counterweight balance position. At this time, the pulling levers at both ends abut against the two ends of the tube body. After this process is completed, the leveling ball slide rod is still in the descending process; Step 4: After the pulling lever clamps and limits the tube body, as the leveling ball slide bar continues to descend, the oil enters the flexible stabilizing mechanism, and the oil pushes the rubber telescopic rod to move away from the cylinder sleeve so that it abuts against the inner wall of the tube body, thereby further limiting the tube body; Step 5: As the leveling ball slide bar continues to descend, the oil inside eventually enters the compensating telescopic cylinder, thereby completing the transfer of the oil inside the leveling ball slide bar. At this time, the leveling ball slide bar enters the embedding groove, the tube body contacts the flexible pad, and is lifted up as the boom body rises.

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