An automatic disassembly and assembly method for large hooks

Abstract

This invention provides an automatic hook assembly / disassembly method, comprising the following steps: fixing hook body chucks and anti-rebound devices arranged vertically on a fixed bracket; hoisting the hook through the hook body chucks, with the lower cylinder of the hook confined within the hook body chucks and anti-rebound devices; moving the sleeve wrench to grip and clamp the upper cylinder of the hook; starting the sleeve wrench to rotate the upper cylinder of the hook, causing the upper cylinder to unfasten or fasten to the lower cylinder of the hook; removing the sleeve wrench and hoisting the hook away, completing the hook assembly / disassembly. Using this automatic hook assembly / disassembly method, the hook is effectively clamped, and the sleeve wrench, powered by a hydraulic station, rotates smoothly with adjustable speed and can rotate bidirectionally, simultaneously achieving hook disassembly and installation. The entire operation is stable and safe, eliminating the need for multiple operators to perform hammering, hoisting, or impact operations, completely eliminating multiple safety hazards and ensuring the safe conduct of hook repairs.

Description

Technical Field

[0001] This invention belongs to the field of drilling equipment, specifically relating to an automatic disassembly and assembly method for a large hook. Background Technology

[0002] The large hook is an important lifting device used in oil and gas drilling and well workover operations to lift and lower drill pipe, tubing, sucker rod and various drilling tools.

[0003] Due to the inherent structural characteristics of the hook—its large and irregular shape, height of approximately 2.5 meters, and weight of approximately 3 tons—its massive and cumbersome appearance makes it difficult to secure and clamp the hook during repairs. Furthermore, the connecting threads of the upper and lower cylinders are left-hand threads, making the disassembly and assembly of the hook particularly difficult.

[0004] Investigations revealed that oilfield equipment repair companies typically employ simple yet laborious methods for disassembling hooks. These methods involve using a crane (or other large equipment to provide traction), attaching one end of a wire rope to the crane, and securing the other end to the upper cylinder of the hook. The crane is then slowly lifted using the wire rope to perform a counter-clockwise uncoupling. However, due to the hook's heavy shape and top-heavy design, as well as gravity, the side of the cylinder thread closest to the ground experiences significantly greater stress than the top. Furthermore, the hook is not horizontal when suspended and tilts considerably due to gravity, causing the lower thread to be compressed, leading to stress accumulation and making uncoupling difficult. A hammer must be used to disperse and buffer the stress; in severe cases, external heating is required before slowly lifting and uncoupling, then hammering again, repeating this process until the lower cylinder thread is completely dislodged.

[0005] The above-mentioned method of disassembling the large hook has the following disadvantages:

[0006] Firstly, after unhooking and tightening, an 18-pound hammer is used to strike the large hook cylinder. The huge impact force acts on the outer surface of the cylinder, and the point of force is very small. This causes the force at the point of force to exceed the critical value of plastic deformation of the cylinder, resulting in damage to the outer surface. Meanwhile, the threads on the inner surface are squeezed and deformed, leading to damage to the cylinder.

[0007] Secondly, when striking still fails to remove stress concentration, external heating is required. This heating method causes uneven heating of the upper and lower cylinders, resulting in different strengths. This reduces the strength of the lower cylinder and makes the threads prone to damage. Statistics show that from 2018 to 2021, the rate of faucet damage and subsequent repairs due to this disassembly method was as high as 16%.

[0008] Third, this detachment method poses a serious safety hazard. Inside the lower cylinder is a pressure spring with a pressure value of up to 20KN. Just as the lower cylinder is about to be spun out, the spring will release a strong elastic force to pop the lower cylinder out. Because the operator must strike at close range, they cannot maintain a safe distance, posing a high risk of injury to personnel.

[0009] Fourth, this disassembly and assembly method is time-consuming and labor-intensive, resulting in high labor intensity and low efficiency.

[0010] Currently, CN203738335U discloses a hook disassembly and assembly device, which mainly uses a ring chuck, a fixed chuck, a hydraulic rotating device, a hydraulic transmission device, and the coordinated use of a left column and a right column to achieve the purpose of disassembling or installing the hook and prevent damage to the hook during repair. However, this disassembly and assembly device still has the problem of the third drawback mentioned above, which can easily cause injury to workers. Summary of the Invention

[0011] The purpose of this invention is to provide an automatic disassembly and assembly method for large hooks to overcome the above-mentioned technical defects.

[0012] To solve the above-mentioned technical problems, the present invention provides an automatic disassembly and assembly method for a large hook, comprising the following steps:

[0013] The hook body chuck and anti-rebound device are fixed on the fixed bracket;

[0014] The lifting hook passes through the hook body chuck, and the lower cylinder of the hook is confined within the hook body chuck and anti-rebound device;

[0015] The movable sleeve wrench grips and clamps the upper cylinder of the large hook;

[0016] Start the sleeve wrench and rotate the upper cylinder of the hook to unfasten or fasten the upper cylinder of the hook to the lower cylinder of the hook;

[0017] Remove the sleeve wrench, lift the hook away, and complete the disassembly and assembly of the hook.

[0018] Furthermore, the fixed bracket includes at least a fixed base, on which two sleeves are fixed. A front column is detachably inserted into each of the two sleeves. A spring is fitted onto the front column, and the lowermost end of each spring is detachably fixed to the corresponding front column.

[0019] Furthermore, each sleeve has a first radial pin hole in the radial direction, and each front column has multiple second radial pin holes in the column body from top to bottom. The front column and the sleeve are connected to each other by pins inserted into the first and second radial pin holes.

[0020] Each spring has a hoop at its lowest end that fits onto the front pillar;

[0021] The hoop is detachably fixed to the front pillar;

[0022] After being compressed, the spring rests on the hoop.

[0023] Furthermore, two rear columns are fixed on the fixed base. The hook body chuck is a frame structure welded from several I-beams and channel steels. The frame has at least a first hole for the upper cylinder of the large hook to pass through, and a second hole for the rear columns to pass through. The frame is fixed on the rear columns and located between the spring and the anti-rebound device.

[0024] Furthermore, the anti-rebound device is fixed to the fixed base or integrally formed with the fixed base. The anti-rebound device is a U-shaped structure made of three plates. The opening of the U-shaped structure faces outward, and the lower cylinder of the large hook is hoisted into the U-shaped structure from the opening.

[0025] Furthermore, the automatic hook assembly / disassembly method includes an automatic hook unhooking process and an automatic hook fastening process, wherein the automatic hook unhooking process is as follows:

[0026] Mount a chuck for fixing the hook body onto the fixed bracket;

[0027] The lifting hook passes through the hook body chuck, and the lower cylinder of the hook is confined within the hook body chuck and anti-rebound device;

[0028] The movable casing wrench grips and clamps the upper cylinder of the large hook, causing the casing wrench to sit on the spring, which is then compressed and contracted.

[0029] Start the sleeve wrench and rotate the upper cylinder of the hook to unscrew the upper cylinder of the hook and detach it from the lower cylinder of the hook;

[0030] Remove the sleeve wrench, lift the cylinder off the hook, and complete the disassembly of the hook.

[0031] Furthermore, the automatic locking process of the large hook is as follows:

[0032] Mount a chuck for fixing the hook body onto the fixed bracket;

[0033] The lower cylinder of the hoisting hook passes through the hook body chuck, and the lower cylinder of the hook is confined within the hook body chuck and the anti-rebound device;

[0034] Move the casing wrench so that it rests on the spring, causing the spring to compress and contract.

[0035] The upper cylinder of the hoisting hook is lowered vertically, so that the upper cylinder of the hook gradually approaches and aligns with the lower cylinder of the hook.

[0036] Start the sleeve wrench to hold and clamp the upper cylinder of the large hook, and rotate it so that the upper cylinder of the large hook is tightly locked to the lower cylinder of the large hook;

[0037] Remove the sleeve wrench to complete the installation of the large hook.

[0038] The beneficial effects of this invention are as follows:

[0039] (1) After using the automatic hook disassembly and assembly method, the hook is effectively clamped, and the sleeve wrench is powered by the hydraulic station, rotates smoothly and the speed is adjustable. It can also rotate in both directions, and at the same time, the hook is disassembled and installed. The disassembly time of the hook thread is shortened by 9.8 times, and the efficiency is significantly improved.

[0040] (2) The vertical disassembly and assembly method is adopted, the large hook is clamped smoothly, the hydraulic transmission is gentle, and the rotation speed and torque before the thread disassembly and assembly are adjustable. Therefore, the entire operation process is stable and safe. The operators do not need to cooperate with multiple people to carry out knocking operations, hoisting operations, object strikes, etc., which completely eliminates many safety hazards and ensures the safe repair of the large hook.

[0041] (3) An anti-rebound device is installed at the bottom of the fixed support to fix the lower cylinder and prevent it from rebounding and injuring people after the unhooking is completed.

[0042] To make the above description of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the device used in the automatic disassembly and assembly method of the large hook.

[0044] Explanation of reference numerals in the attached figures:

[0045] 1. Fixed base; 201. Front column; 202. Rear column; 3. Spring; 4. Hoop; 5. Large hook; 6. Casing wrench; 7. Hook body chuck; 8. Anti-rebound device. Detailed Implementation

[0046] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0047] It should be noted that, in this invention, the top, bottom, left, and right in the figure are regarded as the top, bottom, left, and right of the automatic hook disassembly and assembly method described in this specification.

[0048] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0049] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0050] As a crucial component of the drilling rig hoisting system, the large hook is primarily used for suspending and lowering the drill string, running casing, and changing drill bits during drilling operations. During hook repair, its large size and irregular shape make normal clamping impossible, making hook assembly and disassembly the most challenging aspect of hook maintenance. Therefore, this embodiment proposes an automatic hook assembly and disassembly method, employing automated threaded connections and disassembly to overcome this difficulty and achieve automated hook assembly and disassembly.

[0051] This embodiment protects an automatic hook assembly / disassembly method, including the following steps:

[0052] 7. Hook body chucks and 8. Anti-rebound device are fixed on the fixed bracket.

[0053] The lifting hook 5 passes through the hook body chuck 7, and the lower cylinder of the hook is confined within the hook body chuck 7 and the anti-rebound device 8;

[0054] The movable sleeve wrench 6 grips and clamps the upper cylinder of the large hook;

[0055] Start the sleeve wrench 6 and rotate the upper cylinder of the hook to unfasten or fasten the upper cylinder of the hook to the lower cylinder of the hook;

[0056] Remove the sleeve wrench 6, lift the large hook 5 away, and complete the disassembly and assembly of the large hook 5.

[0057] The aforementioned sleeve clamp 6 can also be called a thread-locking clamp or a hydraulic / pneumatic clamp.

[0058] Based on the elongated structure of the hook and the layout of equipment at the repair site, this implementation method adopts a vertical clamping method to achieve automatic disassembly and assembly of the hook. Specifically, the upper cylinder of the hook is fixed by the sleeve pliers 6, and the lower cylinder of the hook is fixed by the hook body chuck 7 and the anti-rebound device 8. The sleeve pliers 6 are used to clamp the upper cylinder of the hook and realize the bidirectional operation of automatic uncoupling and tightening of the threads, thereby realizing the disassembly and installation of the hook.

[0059] Regarding the sleeve wrench 6, it mainly consists of a clamping mechanism, a power transmission mechanism, a brake band braking mechanism, and an automatic shifting mechanism. In the upper and lower hook cylinder, the main wrench functions as a rotating and punching mechanism. The main wrench is assembled on a support, and the transmission device uses gear transmission. The clamp head uses a roller climbing mechanism, and the main wrench is equipped with a torque detection device that can accurately measure the torque value during the upper and lower hooking process.

[0060] Among them, ① clamping mechanism:

[0061] The clamping mechanism of the main clamp uses a commonly used ramp mechanism to transmit and output motion and torque. Compared with other clamping mechanisms, the ramp clamping mechanism has a more compact structure, transmits larger torque, and has a larger clamping force, which can better clamp the sleeve.

[0062] ② Braking mechanism:

[0063] When the main clamp performs hooking and unhooking operations, the braking device needs to generate braking torque to prevent the jaw plate frame from moving, causing relative sliding between the jaw plate and the jaw plate frame. This forces the jaw plate to clamp the hook body. Once the braking torque is overcome, the jaw plate and jaw plate frame no longer move relative to each other, ultimately completing the hooking and snapping operations. The braking mechanism consists of brake pads, brake pad bases, bolts, and adjusting nuts.

[0064] ③ Power transmission mechanism:

[0065] The clamp body uses a hydraulic motor as its power source. During the clamping and unclamping operations, it performs twisting and punching operations on the hook body, requiring different torques for these two actions. Twisting operations require higher speed and lower torque; punching operations require lower speed but a larger instantaneous torque. A reversing valve is used to switch between different gears, driving high-speed and low-speed gears for rotation and torque transmission. However, unlike ordinary pipe clamps, the high-speed gear should be avoided during unclamping to prevent damage to the clamp shape due to crane misoperation.

[0066] Reference Figure 1 The fixed bracket includes at least a fixed base 1, on which two sleeves are fixed. A front column 201 is detachably inserted into each of the two sleeves. A spring 3 is fitted on the front column 201, and the lower end of each spring 3 is detachably fixed to the corresponding front column 201.

[0067] The fixed bracket is used to clamp the large hook vertically, ensuring that the thread axis is clamped vertically and that the male and female thread axes are completely aligned when engaging and disengaging.

[0068] The reason for setting up the sleeve so that the front post 201 is inserted into the sleeve is to replace the front post 201 of different heights according to different hook structures and heights. Specifically, each sleeve has a first radial pin hole in the radial direction, and each front post 201 has multiple second radial pin holes in the column body from top to bottom. The front post 201 and the sleeve are connected to each other by pins inserted in the first and second radial pin holes.

[0069] In other words, the front post 201 is an adjustable post.

[0070] Reference Figure 1 Each spring 3 has a hoop 4 at its lowest end that is fitted onto the front pillar 201. The hoop 4 is detachably fixed to the front pillar 201 (e.g., by a pin, bolt, screw, etc.). When the spring 3 is compressed, it sits on the hoop 4. The function of the hoop 4 is to limit the position, that is, to restrict the lowest position of the spring 3.

[0071] Two rear uprights 202 are also fixed on the fixed base 1, which are used to install the hook body chuck 7. The structure of the hook body chuck 7 is as follows:

[0072] The hook body chuck 7 is a frame structure welded from several I-beams and channel steels. The frame has at least a first hole for the upper cylinder of the large hook to pass through, and a second hole for the front column 201 to pass through. The frame is fixed on the front column 201 and located between the spring 3 and the anti-rebound device 8.

[0073] In addition, as an alternative, the hook chuck 7 can pass through and be fixed to four posts at the same time.

[0074] Make the hook body chuck 7 according to the hook body mechanism, such as 2150mm high, 1200mm long and 1000mm wide.

[0075] In this embodiment, as a preferred solution, refer to Figure 1 As shown, the four front columns 201 are arranged in a trapezoidal shape. The two front columns 201 in the front row are used to install springs 3. The function of springs 3 is to finely adjust the height of the sleeve clamps 6 to ensure accurate unhooking or fastening of the cylinder on the hook. The hook body chuck 7 is fixed to the two front columns 201 in the rear row by welding. The hook is placed on the hook body chuck 7 using a crane, and the fixing bolts are tightened to achieve vertical installation of the hook.

[0076] like Figure 1 As shown, the anti-rebound device 8 is fixed to the fixed base 1 or integrally formed with the fixed base 1. The anti-rebound device 8 is a U-shaped structure made of three plates. The opening of the U-shaped structure faces outward, and the lower cylinder of the large hook is hoisted into the U-shaped structure from the opening.

[0077] During the assembly and disassembly of the large hook, the upper cylinder rotates with high torque, causing the lower cylinder to rotate in the same direction as the upper cylinder. Therefore, it is necessary to fix the lower cylinder and provide support for the upper cylinder to complete the hook assembly and disassembly. Thus, an anti-rebound device 8 was added to the bracket design. This anti-rebound device 8 is designed as a rectangular structure according to the hook structure at the lower end of the large hook, and it has an opening (U-shaped opening) for easy lifting. The opening diameter meets the hook width requirements of various large hook models such as DG225 / DG315. The anti-rebound device 8 is integrated with the bottom of the overall bracket, effectively ensuring that the hook body does not rotate during disassembly.

[0078] In other words, the function of the anti-rebound device 8 is to fix the lower cylinder and prevent it from rebounding and injuring people after the unhooking is completed.

[0079] The automatic hook assembly and disassembly method includes the automatic hook unhooking process and the automatic hook fastening process.

[0080] The automatic unhooking process of the large hook is as follows:

[0081] Mount a fixed hook body chuck 7 on the fixed bracket;

[0082] The lifting hook 5 passes through the hook body chuck 7, and the lower cylinder of the hook is confined within the hook body chuck 7 and the anti-rebound device 8;

[0083] The movable sleeve wrench 6 holds and clamps the upper cylinder of the large hook, so that the sleeve wrench 6 sits on the spring 3, and the spring 3 is compressed and contracted.

[0084] Start the sleeve wrench 6 and rotate the upper cylinder of the hook to unscrew the upper cylinder of the hook and detach it from the lower cylinder of the hook;

[0085] Remove the sleeve wrench 6, lift it off the upper cylinder of the hook, and complete the disassembly of the hook.

[0086] Alternatively, the automatic locking process of the large hook is as follows:

[0087] Mount a fixed hook body chuck 7 on the fixed bracket;

[0088] The lower cylinder of the hoisting hook passes through the hook body chuck 7, and the lower cylinder of the hook is confined within the hook body chuck 7 and the anti-rebound device 8;

[0089] Move the sleeve clamp 6 so that it sits on the spring 3, and the spring 3 is compressed and contracted.

[0090] The upper cylinder of the hoisting hook is lowered vertically, so that the upper cylinder of the hook gradually approaches and aligns with the lower cylinder of the hook.

[0091] Start the sleeve wrench 6 to hold and clamp the upper cylinder of the large hook and rotate it so that the upper cylinder of the large hook is tightly fastened to the lower cylinder of the large hook;

[0092] Remove sleeve clamp 6 to complete the installation of the large hook.

[0093] During the automatic unhooking and automatic fastening processes of the large hook, the sleeve wrench 6 can be remotely operated via a remote control signal. The hydraulic system of the sleeve wrench 6 drives the transmission system to rotate at low speed, thereby enabling the disassembly and assembly of the large hook.

[0094] The automatic hook assembly and disassembly method transforms manual labor into automated mechanical operation, reducing labor intensity and improving work efficiency. It can realize the assembly and disassembly of various types of hooks. Specifically, it consists of an adjustable hook fixing and disassembly device composed of a TQ675 sleeve wrench, four adjustable columns, and a hook fixing base. Driven by a hydraulic system, it can meet the automatic assembly and disassembly requirements of DG-250, 350, and 450 hooks. The device is easy to operate and can be completed by two people, reducing labor costs.

[0095] The selection of the hydraulic pump station for the hydraulic system is as follows:

[0096]

[0097] Based on the actual well depth at the drilling site and referring to technical parameters such as the tightening torque of the drill pipe joint, the tightening torque value of the M450×6 left-hand thread of the DG-350 hook is calculated to be 30-50 kN·m. To ensure smooth uncoupling of the hook, a value of 50 kN·m is selected; the torque used for uncoupling should be greater than that used for tightening. If dirt falls into the thread, or if there is a lack of oil or rust, the required uncoupling torque will be even greater. According to the technical requirement that the uncoupling torque exceeds 50% of the tightening torque, the uncoupling torque is selected as 50 kN·m. Therefore, the rated output torque value of the hook assembly / disassembly device is set to exceed 75 kN·m, with a maximum value set at 81.5 kN·m. Based on the above analysis, the hydraulic power source of the hook assembly / disassembly device is selected as the HYZ-800B integrated air-cooled hydraulic station.

[0098] In addition, the automatic disassembly and assembly process of the large hook has for the first time realized the mechanized disassembly and assembly of the large hook. The operation process avoids heating and knocking of the cylinder, realizing non-destructive disassembly and assembly, and improving the operation efficiency by more than 50%. The automatic disassembly and assembly process of the large hook adopts wireless remote control operation to ensure that no one is in the dangerous area of ​​disassembly and assembly, reducing the operation risk.

[0099] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. A method for automatically assembling and disassembling a large hook, characterized in that, Includes the following steps: Provide a fixed bracket and fix the large hook (5) on the fixed bracket in a vertical clamping manner to ensure that the thread axes of the upper and lower cylinders of the large hook (5) are completely coincident after clamping; The hook body chuck and anti-rebound device are fixed on the fixed bracket; The lifting hook (5) passes through the hook body chuck (7), and the lower cylinder of the hook is confined within the hook body chuck (7) and the anti-rebound device (8); The movable sleeve wrench (6) grips and clamps the upper cylinder of the large hook; Start the sleeve wrench (6) and rotate the upper cylinder of the hook to unfasten or fasten the upper cylinder of the hook to the lower cylinder of the hook; Remove the sleeve wrench, lift the hook (5) away, and complete the disassembly and assembly of the hook (5); Among them, before the start of the sleeve wrench (6) to rotate the upper cylinder of the hook during the fastening process, the step of vertically lowering the upper cylinder of the hook to gradually approach and align it with the lower cylinder of the hook is also included. The fixed bracket includes at least a fixed base (1), on which two sleeves are fixed. A front column (201) is detachably inserted into each of the two sleeves. A spring (3) is fitted on the front column (201), and the lower end of each spring (3) is detachably fixed to the corresponding front column (201). Two rear columns (202) are also fixed on the fixed base (1). The hook body chuck (7) is a frame structure welded from several I-beams and channel steels. The frame has at least a first hole for the upper cylinder of the large hook to pass through, and a second hole for the rear columns (202) to pass through. The frame is fixed on the rear columns (202) and located between the spring (3) and the anti-rebound device (8). The anti-rebound device (8) is fixed to the fixed base (1) or integrally formed with the fixed base (1). The anti-rebound device (8) is a U-shaped structure made of three plates. The opening of the U-shaped structure faces outward, and the lower cylinder of the large hook is hoisted into the U-shaped structure from the opening.

2. The automatic disassembly and assembly method for the large hook as described in claim 1, characterized in that, Each sleeve has a first radial pin hole in the radial direction, and each front column (201) has multiple second radial pin holes in the column body from top to bottom. The front column (201) and the sleeve are connected to each other by pins inserted in the first and second radial pin holes. Each spring (3) has a hoop (4) fitted onto the front pillar (201) at its lowest end; The hoop (4) is detachably fixed to the front pillar (201); After being compressed, the spring (3) sits on the hoop (4).

3. The automatic disassembly and assembly method for the large hook as described in claim 1, characterized in that, This includes the automatic hook unhooking process and the automatic hook fastening process. The automatic hook unhooking process is detailed below: Mount a fixed hook body chuck (7) on the fixed bracket; The lifting hook (5) passes through the hook body chuck (7), and the lower cylinder of the hook is confined within the hook body chuck (7) and the anti-rebound device (8); The movable sleeve wrench (6) holds and clamps the upper cylinder of the large hook, so that the sleeve wrench (6) sits on the spring (3), and the spring (3) is compressed and contracted. Start the sleeve wrench (6) and rotate the upper cylinder of the hook to unscrew the upper cylinder of the hook and separate it from the lower cylinder of the hook; Remove the sleeve wrench (6), lift it off the upper cylinder of the hook, and complete the disassembly of the hook.

4. The automatic disassembly and assembly method for the large hook as described in claim 3, characterized in that, The automatic locking process of the large hook is as follows: Mount a fixed hook body chuck (7) on the fixed bracket; The lower cylinder of the hoisting hook passes through the hook body chuck (7), and the lower cylinder of the hook is confined within the hook body chuck (7) and the anti-rebound device (8); Move the sleeve clamp (6) so that the sleeve clamp (6) sits on the spring (3), and the spring (3) is compressed and contracted; The upper cylinder of the hoisting hook is lowered vertically, so that the upper cylinder of the hook gradually approaches and aligns with the lower cylinder of the hook. Start the sleeve wrench (6) to hold and clamp the upper cylinder of the hook and rotate it so that the upper cylinder of the hook is tightly fastened to the lower cylinder of the hook; Remove the sleeve wrench (6) to complete the installation of the large hook.

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