High temperature gas cooled reactor core support structure integrated hoisting method and system

Abstract

This application belongs to the field of nuclear power engineering construction technology and discloses an integrated hoisting method and system for the core support structure of a high-temperature gas-cooled reactor. The method connects a hook to a multi-point lifting beam, sequentially connects a plate sensor and a rigging screw, installs a bridge box fixing seat on the upper support plate, and installs an alignment limiting fixture on the upper flange face of the reactor pressure vessel. During the staged loading process of the crane, the stress on each cable is monitored and the length of the rigging screw is adjusted accordingly. The leveled core support structure is lifted to a predetermined height above the ground and inspected. The core support structure is then hoisted above the reactor pressure vessel, and by controlling the gap between the alignment limiting fixture and the outer wall of the core support structure, it is guided into place inside the pressure vessel cylinder. The system includes a transition connecting rod, a multi-point lifting beam, a plate sensor, a rigging screw, a bridge box fixing seat, and an alignment limiting fixture. This application enables safe, stable, and precise hoisting of the core support structure.

Description

Technical Field

[0001] This application belongs to the field of nuclear power engineering construction technology, and in particular relates to an integrated hoisting method and system for the core support structure of a high-temperature gas-cooled reactor. Background Technology

[0002] The core support structure is a critical component of the high-temperature gas-cooled reactor (HTGR). It is a general term encompassing metal, graphite, and carbon core structures, and is an overall cylindrical structure with large dimensions and extremely high weight (maximum external dimensions: φ5680×20160mm; weight approximately 800t). After pre-assembly, the core support structure is hoisted from the pre-assembly building into the reactor pressure vessel. The 10 lifting lugs of the core support structure are located below the equipment, and the center of gravity of the entire structure is above the lifting points. Furthermore, the lugs are unevenly distributed in a 3-3-4 pattern, posing a risk of tipping over. Additionally, after the core support structure enters the pressure vessel, the gap between the connecting bolts of the vessel sections and the inner wall of the pressure vessel on one side is only 38mm, posing a significant risk of scraping against the pressure vessel. Moreover, the location of the connecting bolts is not easily observed after entering the pressure vessel.

[0003] It is evident that the existing technology has the following main problems: First, the equipment has a high center of gravity, and its lifting lugs are located at the bottom of the equipment and are unevenly distributed, which poses a risk of tipping over during the lifting process. Secondly, the narrow internal space of the pressure vessel and the extremely small gap between the equipment and the vessel wall make alignment and positioning during hoisting extremely difficult, which can easily lead to scraping accidents, resulting in high risks and difficulties. Summary of the Invention

[0004] The purpose of this application is to overcome the shortcomings of the prior art. Due to the characteristics of the core support structure, such as large size, high weight, special lifting points and narrow positioning space, this application provides an integrated lifting method and system for the core support structure of a high-temperature gas-cooled reactor, so as to achieve safe, stable and precise lifting of the core support structure.

[0005] To achieve the above objectives, this application provides the following technical solution: In a first aspect, this application provides an integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor, comprising: S1: Connect the hook to the multi-point lifting beam. The plate sensor and the swivel buckle are connected in sequence below the multi-point lifting beam through the rigging. Install the bridge box fixing seat to constrain the lateral displacement of the cable on the upper support plate of the core support structure. The cable passes through the bridge box fixing seat. Install the centering limit tool on the upper flange face of the reactor pressure vessel. S2: During the staged loading process of the crane, monitor the stress on each cable and adjust the length of the rigging screw buckle accordingly to ensure that the posture of the core support structure meets the preset requirements when it is removed from the temporary support. S3: Raise the leveled core support structure to the predetermined height above the ground and inspect it; S4: Hoist the core support structure to the top of the reactor pressure vessel, and guide it into place by controlling the gap between the centering limit tool and the outer wall of the core support structure.

[0006] As an feasible approach, in S1, anti-detachment baffles are installed at the lifting lugs of the core support structure, and limit baffles are installed at the bridge box fixing seat.

[0007] As one feasible approach, in S1, the rigging helical buckle is connected to ten unevenly distributed lifting lugs on the core support structure via cables.

[0008] As one feasible approach, in S1, the cable generates an inward constraint force by tilting inward in the region between the lifting beam and the support plate on the core support structure.

[0009] As an feasible approach, in S2, when the crane loads the load to multiple preset load nodes in stages, the length of the corresponding sling screw is adjusted according to the monitoring data of the plate sensor, so that the force on the sling at each lifting point does not exceed the set value, and the verticality deviation of the core support structure cylinder is ≤10mm, and the horizontality of the upper surface of the support plate is ≤2.5mm.

[0010] As an feasible approach, in S2, the crane performs graded loading. When the load reaches T1=K+240t, T2=K+480t, T3=K+720t, and T4=K+800t respectively, the length of the corresponding sling screw is adjusted according to the monitoring data of the plate sensor so that the final force on the sling at each lifting point does not exceed 100t.

[0011] As an feasible approach, in S3, the braking performance of the crane is checked by raising the core support structure by 95~105mm and then lowering it by 45~55mm, with the wind speed ≤7.9m / s and the ambient temperature -20℃~40℃ during the test lift.

[0012] As an feasible approach, in S4, when the lower end of the core support structure descends to 95~105mm from the upper flange of the pressure vessel, it is confirmed that the gap between its outer wall and the centering limit fixture is uniform.

[0013] As an feasible approach, in S4, when the core support structure is hoisted out of the pre-assembly building or into the reactor pressure vessel, the change in lifting load is controlled to be no more than 10t.

[0014] Secondly, this application provides an integrated hoisting system for the core support structure of a high-temperature gas-cooled reactor, used to implement the above method, including: Transition connecting rod, used for connection with crane hook; The multi-point lifting beam has its lifting points distributed in accordance with the distribution of the lifting lugs of the reactor core support structure; Plate-type sensors are connected below the multi-point lifting beam to monitor the force at each lifting point; The rigging screw buckle, connected below the plate sensor, is used to adjust the rigging length; The bridge box mounting base is used to be installed on the upper support plate of the core support structure. It has a channel for cables to pass through in order to restrain the lateral displacement of the cables. The centering and limiting fixture is installed on the upper flange face of the reactor pressure vessel to guide and limit the core support structure during hoisting and positioning.

[0015] Compared with existing technologies, the integrated hoisting method and system for the high-temperature gas-cooled reactor core support structure provided in this application have the following advantages: In this application, the cables at the ten lifting points of the core support structure are inclined inward at a certain angle in the area from the lifting beam to the support plate on the core support structure, thereby generating an inward restraining force and reducing the risk of overturning during the hoisting of the core support structure.

[0016] This application includes controlling and adjusting the equipment's attitude during hoisting. It introduces centering and limiting fixtures during the core support structure's entry into the pressure vessel. Simultaneously, installers are stationed at the main flange of the pressure vessel to monitor the gap between the pressure vessel and the outer wall of the core shell. This solves the problems of a mere 38mm gap between the cylinder section connecting bolts and the inner wall of the pressure vessel cylinder, a significant risk of scraping between the core support structure and the pressure vessel cylinder, and the difficulty in directly observing the bolt positions after entry into the pressure vessel cylinder. This prevents collisions or scrapes between equipment, ensuring the quality of the integrated hoisting of the core support structure.

[0017] This application reduces the difficulty of construction and improves the construction environment, which is of great significance for improving the construction level of nuclear power projects and the economics of high-temperature gas-cooled reactor nuclear power, and for promoting the implementation and commercialization of the major science and technology project on high-temperature gas-cooled reactors.

[0018] Furthermore, this application achieves precise force balance and attitude control for equipment with irregularly distributed lifting points through a closed-loop leveling system consisting of a multi-point lifting beam, a plate sensor, and a rigging screw buckle, fundamentally overcoming the risk of overturning.

[0019] Furthermore, this application employs a bridge box fixing seat, which effectively constrains the lateral swing of the long cable, improves the system rigidity, and ensures the stability of the hoisting process.

[0020] Furthermore, this application adopts a combination of centering limit fixtures and manual multi-point monitoring, which effectively solves the problem of precise positioning under millimeter-level gaps, avoids equipment scratches, and ensures hoisting safety and quality.

[0021] Furthermore, the control parameters of this application (such as plumbness ≤10mm, horizontality ≤2.5mm, load variation ≤10t, etc.) form a repeatable and verifiable high-standard construction process. Attached Figure Description

[0022] To more clearly illustrate the technical solution of this application, the accompanying drawings used in the technical description will be briefly introduced below.

[0023] Figure 1 A flowchart of the integrated hoisting method for the high-temperature gas-cooled reactor core support structure provided in this application; Figure 2 This is a schematic diagram of the sling connection provided in this application; Figure 3 A top view of the bridge box provided in this application; Figure 4 A front view of the bridge box provided for this application; Figure 5 A top view of the transition connecting rod and multi-point lifting beam provided in this application; Figure 6 A front view of the transition connecting rod and multi-point lifting beam provided in this application; Figure 7 A perspective view of the plate sensor provided in this application; Figure 8 This is a front view of the plate sensor provided in this application; Figure 9 A schematic diagram of the rigging spiral buckle provided in this application; Figure 10 This is a schematic diagram showing the installation position of the centering limit block provided in this application.

[0024] Explanation of reference numerals in the attached figures: 2-1. Transition connecting rod; 2-2. Multi-point lifting beam; 2-3. Plate sensor; 2-4. Bridge box fixing seat; 2-5. Cable; 2-6. Shackle; 2-7. Rigging spiral buckle; 2-8. Lifting lug; 7-1. Centering limit block; 7-2. Main flange face of pressure vessel; 7-3. Upper flange face of pressure vessel. Detailed Implementation

[0025] The following detailed description provides further details on specific implementation methods.

[0026] like Figure 1As shown, this application provides an integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor, including steps of connecting slings, leveling, trial hoisting, and hoisting into place, specifically including: S1. Lifting sling connection steps: Connect the hook to the multi-point lifting beam 2-2. Below the multi-point lifting beam 2-2, connect the plate sensor 2-3 and the sling screw 2-7 in sequence via slings. Install the bridge box fixing seat 2-4 on the upper support plate of the core support structure to constrain the lateral displacement of the cable 2-5. The cable passes through the bridge box fixing seats 2-4 and 3-2. Install the centering limit fixture on the upper flange face 7-3 of the reactor pressure vessel. Details are as follows: First, a large-tonnage crane is selected as the main crane. In the lifting area, the upper end of the transition connecting rod 2-1 is reliably connected to the crane hook, and the lower end is connected to a specially designed multi-point lifting beam 2-2. The distribution of the lifting points of this multi-point lifting beam must strictly match the ten lifting lugs 2-8 (distributed unevenly in 3, 3, and 4) at the bottom of the reactor core support structure.

[0027] Below each lifting point of the multi-point lifting beam 2-2, a shackle 2-6, a plate sensor, and a rigging screw 2-7 (also known as a turnbuckle) are connected in sequence. The plate sensor is used to monitor the stress on each lifting cable 2-5 in real time. The rigging screw 2-7 is a key component for subsequent leveling; adjusting its thread length changes the tension of the corresponding cable 2-5. The lower end of the rigging screw 2-7 is finally connected to the corresponding lifting lug of the reactor core support structure via a high-strength cable 2-5.

[0028] A crucial installation step involves pre-installing multiple bridge box fixing seats 2-4 on the upper support plate at the top of the reactor core support structure. Each cable passes downwards through its corresponding bridge box fixing seat 2-4 or 3-2 and then connects to the lower lifting lug 2-8. The core function of the bridge box fixing seat 2-4 is to constrain the lateral displacement or swing of the cable 2-5 in the horizontal direction, ensuring that it primarily transmits vertical tension. This significantly enhances the overall rigidity and stability of the hoisting system and effectively suppresses equipment swaying in the air.

[0029] In addition, an adjustable centering limit fixture 7-1 needs to be pre-installed on the upper flange face 7-3 of the reactor pressure vessel. This fixture usually consists of multiple limit blocks evenly distributed on the flange circumference, which are used to provide mechanical guidance and limit during subsequent hoisting and positioning.

[0030] As a safety measure, anti-detachment baffles should be installed at the connection of lugs 2-8, limit baffles should be installed at bridge box fixing seats 2-4, and guide ropes for fine-tuning the equipment's orientation should be installed.

[0031] S2. Leveling Step: During the staged loading process of the crane, monitor the stress on each cable and adjust the length of the sling buckles 2-7 accordingly to ensure that the core support structure meets the preset requirements when it is removed from the temporary support. Details are as follows: Due to the high center of gravity and uneven distribution of lifting points, leveling is a prerequisite for ensuring lifting safety. Leveling is carried out simultaneously with the crane's staged loading process.

[0032] The crane begins to slowly load the load, pausing when the load reaches several preset key nodes (e.g., T1=K+240t, T2=K+480t, T3=K+720t, T4=K+800t, where K is the weight of the slings). At each node, the operator observes the force distribution at the ten lifting points based on real-time data transmitted from the plate sensors. If the force is uneven, the length of the corresponding sling helical buckles 2-7 is finely adjusted to change the tension of the cable at that lifting point, thus balancing the force at each point. This process may need to be repeated several times.

[0033] The ultimate goal of leveling is to simultaneously meet two key geometric parameters when the core support structure is completely detached from its temporary bottom support: First, the vertical deviation of the equipment cylinder at the four quadrant points (0°, 90°, 180°, 270°) shall not exceed 10mm; Second, the levelness of the upper surface of the top support plate must not exceed 2.5mm.

[0034] At the same time, it must be ensured that the force on the slings at each lifting point does not exceed its safe working load (e.g., 100t) after adjustment. If the measurement results do not meet the requirements, the equipment must be lowered back to the temporary support and readjusted until it fully meets the standards.

[0035] S3. Trial Lifting Procedure: Lift the leveled core support structure to the predetermined height above the ground and inspect it. Specifically, this includes: Before the formal lifting operation, a trial lift must be conducted to comprehensively verify the reliability of the entire lifting system. The trial lift has strict environmental requirements: the wind speed must not exceed 7.9 m / s, and there must be no rain or fog, and the ambient temperature must be between -20℃ and 40℃.

[0036] The crane slowly and steadily lifts the leveled core support structure approximately 100mm, then lowers it about 50mm. This operation is to test the crane's braking performance and to check for any abnormalities in the entire lifting system (including connection points, rigging, monitoring instruments, etc.). During the trial lift, the plumbness and levelness of the equipment must be checked again to ensure they still meet the requirements. The crane operator must monitor the load display throughout the process to ensure smooth load changes. Only after all checks and confirmations are satisfactory can the formal lifting operation commence.

[0037] S4. Lifting and Positioning Procedure: The core support structure is lifted to the top of the reactor pressure vessel, and guided into position by controlling the gap between the centering limiting tool 7-1 and the outer wall of the core support structure. Specifically, this includes: The crane lifted the core support structure out of the pre-assembly building and rotated it to a position directly above the reactor building's pressure vessel. By operating the crane, the center of the core support structure was initially aligned with the center of the pressure vessel shell.

[0038] The most delicate operation is required when the lower end of the equipment is about to enter the pressure vessel shell. The circumferential angle of the equipment needs to be finely adjusted using a guide rope to ensure that the direction of its hot gas duct flange aligns with the corresponding flange on the pressure vessel. When the equipment descends to approximately 100mm from its bottom end to the upper flange face 7-3 of the pressure vessel, the descent is paused, and it is confirmed that the gap between the outer wall of the equipment and the multiple sets of alignment and limiting fixtures 7-1 installed around it is uniform.

[0039] Subsequently, the crane descends at an extremely slow speed, and the centering limit fixtures begin to play a crucial mechanical guiding role. By precisely controlling the uniform, minute gap between the limit blocks and the equipment cylinder wall (for example, ensuring that the sway amplitude is controlled within 5mm when the lower end of the equipment contacts the flange surface), the equipment is guided smoothly and centered into the narrow cylinder space. During this process, the gaps between the outer wall of the equipment and the inner wall of the vessel, as well as between the equipment and each centering limit fixture 7-1, are monitored from different positions at the main flange of the pressure vessel. If any abnormal gap or risk of scraping is detected at any observation point, an immediate command must be issued to stop the descent.

[0040] When the equipment descends to the point where the guide key at the top approaches the positioning slot plate inside the pressure vessel, it needs to be paused again to confirm that the guide key can smoothly enter. Finally, the equipment descends smoothly and is precisely positioned on the core shell support at the bottom of the pressure vessel, completing the entire hoisting operation.

[0041] Throughout the entire lifting and lowering process, the crane operation must remain stable, and any sudden increase or decrease in load should be controlled within 10t. If this threshold is exceeded, the operation must be stopped immediately and the cause investigated.

[0042] In addition, such as Figures 2 to 10 As shown, this application also provides an integrated hoisting system for the core support structure of a high-temperature gas-cooled reactor, including a transition connecting rod 2-1, a multi-point lifting beam 2-2, a plate sensor 2-3, a rigging screw buckle 2-7, a bridge box 2-4, and a centering limit fixture 7-1.

[0043] The transition connecting rod 2-1 serves as a connecting component between the crane hook and the lower lifting device.

[0044] The distribution design of the lifting points on the multi-point lifting beam 2-2 is perfectly matched with the uneven distribution of the ten lifting lugs 3, 3, and 4 on the core support structure to achieve a reasonable distribution of force.

[0045] The plate-type sensor is connected below each lifting point of the multi-point lifting beam 2-2. Its function is to monitor the tension of the corresponding lifting cable 2-5 in real time and online, providing data for leveling.

[0046] The rigging spiral buckle 2-7 is connected below the plate sensor. Its function is to adjust the tension of the corresponding cable by adjusting its own length. It is a key actuator for active leveling.

[0047] The bridge box fixing seat 2-4 is pre-installed on the upper support plate of the reactor core support structure. It has a channel for the cables to pass through, and its core function is to restrain the lateral displacement of the cables 2-5, prevent them from swinging significantly during hoisting, and thus improve the stability of the hoisting system.

[0048] The centering and limiting fixture 7-1 is pre-installed on the upper flange face 7-3 of the reactor pressure vessel. Its function is to mechanically guide and radially limit the falling equipment during the hoisting and positioning stage through the adjustable gap formed between it and the outer wall of the core support structure, ensuring that it is accurately centered and inserted into the narrow cylindrical space.

[0049] like Figure 3 and Figure 4 As shown, the bridge box has a cylindrical structure. Bolt holes are provided on the lower flange of the bridge box for connecting and fixing it to the upper support plate. Ten limiting grooves are provided on the side of the bridge box for limiting the movement of the wire rope.

[0050] like Figure 5 and Figure 6 As shown, the transition connecting rod 2-1 and the multi-point lifting beam are connected by a pin and installed above the core support structure.

[0051] like Figure 7 and Figure 8 As shown, the plate sensor 2-3 monitors the weight change of each lifting point in real time through the built-in sensor and wireless transmission system.

[0052] like Figure 9 As shown, the rigging screw 2-7 is an adjustment device consisting of two left-handed and right-handed screws, which connect to a plate sensor and a wire rope and are used to adjust the levelness of the reactor core support structure.

[0053] like Figure 10 As shown, the centering limit block 7-1 has a U-shaped structure with a set screw at the tail for adjustment and fixation. Installed on the upper flange of the pressure vessel, it restricts the orientation of the core support structure within the pressure vessel, preventing collision between the core support structure and the pressure vessel.

[0054] Example This embodiment describes the implementation steps of an integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor, including the following basic steps: Step 1: Connect the slings.

[0055] When opening the roof of the pre-assembled factory building, if a 3600t crawler crane is used for opening the roof, the roof should be opened before the slings are connected. If other cranes are used for opening the roof, the opening of the roof and the connection of the slings can be done in parallel.

[0056] Lay wooden planks or fireproof cloth to isolate the area from the ground in the dedicated sling assembly area. Use a 25t or larger truck crane to place the transition connecting rod 2-1 onto the sleepers to facilitate connection with the hook of the 3600t crawler crane.

[0057] The hook of the 3600t crawler crane is lowered to about 1.5m above the ground. Targets are set near both ends of the crossbeam of the 3600t crawler crane for synchronous monitoring during the lifting and lowering process.

[0058] The 3600t crawler crane adjusts the hook to be directly above the transition connecting rod 2-1 through luffing, traveling, and lifting / lowering hooks, thus completing the connection between the hook and the transition connecting rod 2-1.

[0059] Lift the hook of the 3600t crawler crane to raise the transition connecting rod 2-1 about 2m off the ground.

[0060] Install shackle 2-6, plate sensor, and rigging screw buckle below multi-point lifting beam 2-2. Adjust the length of the rigging screw buckle before installation to ensure consistency.

[0061] The 3600t crawler crane slowly lifts the hook until the lower end of the rigging screw 2-7 is off the ground.

[0062] Arrange cable 2-5 in advance according to the lifting point positions of multi-point lifting beam 2-2. Use a 3600t crawler crane to lift multi-point lifting beam 2-2 to the cable position and connect the cables.

[0063] A 3600t crawler crane moved the slings above the reactor core support structure.

[0064] The 3600t crawler crane lowers its hook to connect the slings to the core support structure. Before each hooking, a dedicated person monitors the condition of the thin pads at each lifting point to prevent slippage.

[0065] Inspection confirmed that the cables at 24°, 144°, 216°, and 336° did not interfere with the absorption ball lifting pipe.

[0066] Tighten cable 2-5 to ensure that there is no interference between the connecting bolts of the cable and the cylinder section.

[0067] After cable 2-5 is connected, anti-detachment baffles are installed at the lugs of the core support structure. Then, the 3600t crawler crane slowly lifts the hook, and when the cable begins to bear force, an appropriate amount of load is applied to adjust and straighten the cable.

[0068] Install limit baffles at positions 2-4 of the bridge box mounting base.

[0069] Verify that the thermocouples installed at the bottom are protected and securely fixed, and confirm that they will not affect the placement of the core support structure.

[0070] Tie the guide rope at a suitable position at the bottom of the core support structure.

[0071] Step 2: Leveling the core support structure.

[0072] Connect the data transmission system of the plate sensor and check to confirm that the signal is normal.

[0073] It has been confirmed that all connections between the core support structure and surrounding facilities have been removed.

[0074] The crawler crane is subjected to graded loading. When the load on the crawler crane reaches T1=K+240t, T2=K+480t, T3=K+720t, and T4=K+800t respectively, the relevant on-site cable force monitoring data is used to determine the load. The corresponding lifting slings are then adjusted by using the sling screws 2-7 to adjust the load so that the load on the lifting slings does not exceed 100t.

[0075] During the loading process, observe the verticality of the wire rope. If necessary, adjust it by rotating and changing the amplitude of the crane to ensure that the hook and the center of gravity of the equipment are on the same vertical line until the core support structure is completely detached from the temporary support.

[0076] The vertical deviation of the four quadrant points of the reactor core shell should be ≤10mm, and the horizontality of the upper support plate should be ≤2.5mm. If these requirements are not met, the reactor core support structure should be lowered to the temporary support and adjusted until the vertical deviation of the four quadrant points of the reactor core shell is ≤10mm, the horizontality of the upper support plate is ≤2.5mm, and the force on each lifting point does not exceed the rated load.

[0077] After the core support structure is leveled, before the formal hoisting, the core support structure can be temporarily lowered onto the temporary support, and the crawler crane can be loaded with an appropriate amount of load to prevent the slings from shifting.

[0078] Remove the anti-detachment baffles at the lugs of the core support structure.

[0079] Step 3: Trial lifting.

[0080] Before the trial lift, the wind speed must be monitored in real time. The lifting operation can only be carried out when the wind speed is less than or equal to 7.9 m / s, and there is no rain or fog, and the outdoor temperature is not lower than -20℃ and not higher than 40℃.

[0081] The operator of the 3600t crawler crane must constantly monitor the crane's lifting load. If the increase or decrease in the lifting load is greater than or equal to 10t, the operator must promptly transmit the information to the main crane operator.

[0082] The 3600t crawler crane slowly raises its hook, with the crane operator closely monitoring the crane's weight display. After raising the hook by approximately 100mm, the crane stops and then lowers it 50mm to check and confirm that the crane's braking performance is good.

[0083] During the trial lifting, it was checked again to ensure that the vertical deviation of the four quadrant points of the reactor core shell was ≤10mm and the horizontality of the upper support plate was ≤2.5mm.

[0084] Step 4: The core support structure is hoisted and positioned.

[0085] The 3600t crawler crane slowly raises the hook until the bottom of the equipment is about 200mm above the temporary support surface.

[0086] The equipment orientation is roughly adjusted based on the placement of the core support structure.

[0087] The 3600t crawler crane slowly lifts the hook, and after it is above the steel platform at the lower end of the core support structure, it shortens the guide rope.

[0088] The 3600t crawler crane continued lifting, hoisting the reactor core support structure out of the pre-assembly building until the bottom elevation of the equipment reached 48m. If the reactor building height is less than 46m, the height can be appropriately reduced.

[0089] The 3600t crawler crane rotates counterclockwise.

[0090] When the 3600t crawler crane reaches the equipment placement point, it stops rotating and then adjusts the working radius by changing the luffing until the center of the core support structure is aligned with the center of the pressure vessel shell.

[0091] When the core support structure is hoisted into the reactor building, the hoisting chief commander transfers command to the hoisting deputy commander at the top of the nuclear island pressure vessel compartment via walkie-talkie. After the hoisting chief commander arrives at the top of the nuclear island pressure vessel compartment, the hoisting deputy commander then transfers command back to the hoisting chief commander.

[0092] The 3600t crawler crane slowly lowers its hook to a height of about 500mm from the bottom of the equipment to the upper flange of the pressure vessel. The operators then release the guide rope and adjust the installation angle and orientation of the equipment according to the installation baseline to ensure that the hot gas duct flange of the reactor core shell and the hot gas duct flange of the reactor pressure vessel are aligned.

[0093] When the reactor descends to about 100 mm from the top of the pressure vessel, it is confirmed that the gap between the outer wall of the core support structure and the six sets of centering limit block assemblies is uniform.

[0094] The hook descends slowly, and the crawler crane can perform slewing and luffing movements for necessary adjustments. By controlling the gap between the centering limit block and the core shell wall, the sway amplitude of the core shell after its lower end descends to the main flange face of the reactor pressure vessel is ensured to be ≤5mm.

[0095] The core support structure is slowly inserted into the pressure vessel shell. During the insertion process, no fewer than 6 installation personnel are stationed at the main flange of the pressure vessel to monitor the gaps between the inner wall of the pressure vessel and the outer wall of the core support structure, as well as between the centering limit block and the outer wall of the core support structure.

[0096] When the core support structure is hoisted into the pressure vessel, the increase or decrease in the hoisting load shall not exceed 10t.

[0097] The equipment continues to descend until the lower section of the guide key on the core support structure is about 100mm away from the upper surface of the circumferential positioning slot plate of the pressure vessel. Then, check and confirm the installation position of the equipment again, and check whether the gap between the guide key on the top of the core support structure and the circumferential positioning slot plate of the reactor pressure vessel is uniform, to ensure that the guide key can enter the circumferential positioning slot plate.

[0098] The 3600t crawler crane slowly lowered the hook until the core support structure was in place at the core shell support seat.

[0099] The above description is only a specific embodiment of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application.

Claims

1. A method for integrated hoisting of a high-temperature gas-cooled reactor core support structure, characterized in that, include: S1: Connect the hook to the multi-point lifting beam. The plate sensor and the swivel buckle are connected in sequence below the multi-point lifting beam through the rigging. Install the bridge box fixing seat to constrain the lateral displacement of the cable on the upper support plate of the core support structure. The cable passes through the bridge box fixing seat. Install the centering limit tool on the upper flange face of the reactor pressure vessel. S2: During the staged loading process of the crane, monitor the stress on each cable and adjust the length of the rigging screw buckle accordingly to ensure that the posture of the core support structure meets the preset requirements when it is removed from the temporary support. S3: Raise the leveled core support structure to the predetermined height above the ground and inspect it; S4: Hoist the core support structure to the top of the reactor pressure vessel, and guide it into place by controlling the gap between the centering limit tool and the outer wall of the core support structure.

2. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S1, anti-detachment baffles are installed at the lifting lugs of the core support structure, and limit baffles are installed at the bridge box fixing seat.

3. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1 or 2, characterized in that, In S1, the rigging helical buckle is connected to ten unevenly distributed lifting lugs on the core support structure via cables.

4. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S1, the cable generates an inward constraint force by tilting inward in the area between the lifting beam and the support plate on the core support structure.

5. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S2, when the crane loads the load to multiple preset load nodes in stages, the length of the corresponding sling screw is adjusted according to the monitoring data of the plate sensor to ensure that the force on the sling at each lifting point does not exceed the set value, and that the verticality deviation of the core support structure cylinder is ≤10mm, and the horizontality of the upper surface of the support plate is ≤2.5mm.

6. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S2, the crane performs graded loading. When the load reaches T1=K+240t, T2=K+480t, T3=K+720t, and T4=K+800t respectively, the length of the corresponding sling screw is adjusted according to the monitoring data of the plate sensor so that the final force on the sling at each lifting point does not exceed 100t.

7. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S3, the braking performance of the crane is checked by raising the core support structure by 95~105mm and then lowering it by about 45~55mm. During the test lift, the wind speed is ≤7.9m / s and the ambient temperature is -20℃~40℃.

8. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S4, when the lower end of the core support structure descends to 95~105mm from the upper flange of the pressure vessel, confirm that the gap between its outer wall and the centering limit tool is uniform.

9. The integrated hoisting method for the core support structure of a high-temperature gas-cooled reactor according to claim 1, characterized in that, In S4, when the core support structure is lifted out of the pre-assembly building or into the reactor pressure vessel, the change in lifting load is controlled to be no more than 10t.

10. An integrated hoisting system for the core support structure of a high-temperature gas-cooled reactor, characterized in that, For implementing the method as described in any one of claims 1 to 9, comprising: Transition connecting rod, used to connect to the hook of the crane; The multi-point lifting beam has its lifting points distributed in accordance with the distribution of the lifting lugs of the reactor core support structure; Plate-type sensors are connected below the multi-point lifting beam to monitor the force at each lifting point; The rigging screw buckle, connected below the plate sensor, is used to adjust the rigging length; The bridge box mounting base is used to be installed on the upper support plate of the core support structure. It has a channel for cables to pass through in order to restrain the lateral displacement of the cables. The centering and limiting fixture is installed on the upper flange face of the reactor pressure vessel to guide and limit the core support structure during hoisting and positioning.

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