Method for hoisting radioactive pressure vessel

Abstract

The invention relates to the technical field of radioactive container treatment, and provides a radioactive pressure container hoisting method, a hoisting instrument and a shielding device are used for hoisting a radioactive pressure container, one side of the radioactive pressure container in the height direction is provided with an opening, and the hoisting method comprises the steps that the shielding device covers the opening and is fixedly arranged; the shielding device is leveled, and a lifting hook of the lifting instrument is aligned with the shielding device; the lifting hook and the shielding device are connected, and the radioactive pressure container is lifted to a designated position to be cut and disassembled. According to the hoisting method for the radioactive pressure container, the radioactive pressure container can be integrally hoisted out of a pile, so that the decommissioning efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of radioactive container handling technology, and in particular to a method for hoisting a radioactive pressure vessel. Background Technology

[0002] With the permanent closure of more and more nuclear power units, nuclear facilities are experiencing a peak in decommissioning. The in-reactor radioactive pressure vessel is a crucial part of reactor decommissioning, and its decommissioning process involves hoisting. For in-reactor radioactive pressure vessels, the current method of dismantling them within the reactor and then hoisting them in sections is inefficient. Therefore, a method is needed to hoist the radioactive pressure vessel as a whole off the reactor for dismantling. Summary of the Invention

[0003] This application provides a method for hoisting a radioactive pressure vessel, which can hoist the entire radioactive pressure vessel out of the reactor, thereby improving decommissioning efficiency.

[0004] The technical solution of this application embodiment is implemented as follows: This application provides a method for hoisting a radioactive pressure vessel, which utilizes hoisting equipment and a shielding device to hoist the vessel. The radioactive pressure vessel has an opening on one side along its height. The hoisting method includes: The shielding device is placed over the opening and fixed in place. Level the shielding device and align the hook of the hoisting equipment with the shielding device; Connect the hook to the shielding device, and hoist the radioactive pressure vessel to the designated location for cutting and dismantling.

[0005] In one embodiment, the shielding device includes a shielding barrel and a lifting device. The lifting device is connected to one end of the shielding barrel along the height direction. The shielding barrel is used to contain shielding liquid. With the lifting device covered and fixed to the opening, the shielding barrel is inserted into the radioactive pressure vessel. The lifting device is used to connect to the hook.

[0006] In one embodiment, the shielding device includes a plurality of shielding plates, which are stacked along the height direction and connected between the lifting device and the shielding barrel.

[0007] In one embodiment, the diameter of the shielding barrel gradually decreases along the height direction toward the direction away from the lifting device.

[0008] In one embodiment, the shielding device is provided with multiple rigging helices, which are arranged at intervals along the circumference of the radioactive pressure vessel; the hoisting method includes: The shielding device is leveled using a spirit level and the screw rod of the rigging auger.

[0009] In one embodiment, the step of aligning the hook with the shielding device includes: Hang the laser plumb bob on the hook and adjust the hook so that the laser emitted by the laser plumb bob is aligned with the center of the shielding device.

[0010] In one embodiment, before connecting the hook and the shielding device and hoisting the radioactive pressure vessel to a designated location for cutting and dismantling, the hoisting method includes: A trial hoisting was performed on the radioactive pressure vessel to confirm that there were no attachments on its outer perimeter.

[0011] In one embodiment, the hoisting method includes: By installing a force gauge between the hook and the shielding device, and based on the measured value of the force gauge and the combined mass of the radioactive pressure vessel and the shielding device, it can be determined whether there are any attachments on the outer periphery of the radioactive pressure vessel.

[0012] In one embodiment, if the measured value is less than 1.05 times the sum of the weights of the radioactive pressure vessel and the shielding device, it is determined that there are no attachments on the outer periphery of the radioactive pressure vessel.

[0013] In one embodiment, the hoisting method includes: After the radioactive pressure vessel is hoisted and held for a set time, it is confirmed that the radioactive pressure vessel does not deform within the set time.

[0014] The radioactive pressure vessel provided in this application embodiment reduces the risk of radiation leakage to operators and provides a lifting position for hoisting equipment by first covering and fixing the shielding device over the opening. Before hoisting, leveling the shielding device and aligning the hook with it reduces the risk of oblique pulling during hoisting, thus minimizing the possibility of the radioactive pressure vessel hitting or getting stuck on other structures within the reactor. Finally, after leveling and alignment, the hook and shielding device are connected, and the entire radioactive pressure vessel is hoisted to a designated location for cutting and dismantling. This not only improves the processing efficiency of the radioactive pressure vessel and thus its decommissioning efficiency, but also provides a simple hoisting method with readily available and economical hoisting equipment and shielding devices, enabling remote hoisting of the entire radioactive pressure vessel to a designated location for further cutting. Attached Figure Description

[0015] Figure 1 A schematic diagram of a radioactive pressure vessel provided for an embodiment of this application; Figure 2A schematic diagram of the shielding device, hook, and radioactive pressure vessel provided in the embodiments of this application; Figure 3 A cross-sectional schematic diagram of the shielding device, hook, and part of the radioactive pressure vessel provided in the embodiments of this application; Figure 4 for Figure 2 A top-down view; Figure 5 This is a cross-sectional schematic diagram of the shielding barrel and shielding plate provided in the embodiments of this application.

[0016] Explanation of reference numerals in the attached figures 100. Shielding device; 1. Shielding barrel; 11. Barrel body; 11a. Receiving cavity; 12. Cover; 2. Lifting device; 2a. Second mounting hole; 2b. Third mounting hole; 2c. Lifting lug; 3. Shielding plate; 3a. First shielding plate; 3b. Second shielding plate; 4. Rigging screw; 200. Hook; 300. Radioactive pressure vessel. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0018] In the following description, reference is made to "an embodiment," which describes a subset of all possible embodiments. However, it is understood that "an embodiment" may be the same subset or a different subset of all possible embodiments and may be combined with each other without conflict.

[0019] In the following description, the terms "first" and "second" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first" and "second" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0020] This application provides a method for hoisting a radioactive pressure vessel 300. The method utilizes hoisting equipment and a shielding device 100 to hoist the radioactive pressure vessel 300. The radioactive pressure vessel 300 has an opening on one side along its height direction. (See also...) Figures 1 to 5 The hoisting methods include: S1. Cover the opening with the shielding device and fix it in place; S2. Level the shielding device and align the hook of the hoisting equipment with the shielding device; S3. Connect the hook to the shielding device, and hoist the radioactive pressure vessel to the designated position for cutting and dismantling.

[0021] Lifting equipment can be cranes such as truck cranes and crawler cranes.

[0022] The shielding device 100 refers to the device used to seal and shield the radiation from the radioactive pressure vessel 300 and to provide a lifting position for the hook 200 of the lifting equipment.

[0023] The shape of the radioactive pressure vessel 300 can be cylindrical, cuboid, or cube, etc.

[0024] It should be noted that the radioactive pressure vessel 300 is severely activated inside the reactor under in-reactor irradiation, therefore, its openings need to be sealed during hoisting.

[0025] For example, the radioactive pressure vessel 300 can be an in-pile movable pressure vessel.

[0026] For example, the shielding device 100 can be fixed to the opening by fasteners, such as mounting ears formed on the edge of the opening of the radioactive pressure vessel 300, the mounting ears forming a first mounting hole, and the outer edge of the shielding device 100 forming a second mounting hole 2a. Fasteners such as bolts are inserted into the first mounting hole and the second mounting hole 2a to complete the sealing and fixing.

[0027] For example, the shielding device 100 can be placed over the opening using hoisting equipment, and then it can be secured manually by an operator or by a robotic arm.

[0028] The lifting method for the radioactive pressure vessel 300 provided in this application reduces the risk of radiation leakage to operators and provides a lifting position for the lifting equipment by first covering and fixing the shielding device 100 over the opening. Before lifting, leveling the shielding device 100 and aligning the hook 200 with it reduces the risk of oblique pulling during lifting, thus minimizing the possibility of the radioactive pressure vessel 300 hitting or being jammed by other structures within the reactor. Finally, after leveling and alignment, the hook 200 and shielding device 100 are connected, and the radioactive pressure vessel 300 is lifted as a whole to the designated location for cutting and dismantling. This not only improves the processing efficiency of the radioactive pressure vessel 300 and consequently its decommissioning efficiency, but also provides a simple lifting method, readily available and economical lifting equipment and shielding device 100, enabling remote lifting of the radioactive pressure vessel 300 as a whole to the designated location for further cutting.

[0029] For example, in one embodiment, in order to reduce the installation time of the shielding device 100 and the operation time of adjusting the shielding device 100 to align with the opening, the basic alignment between the shielding device 100 and the radioactive pressure vessel 300 can be ensured by marking the shielding device 100 with marks such as the center position and key orientation of the shielding device 100 between the two devices during installation.

[0030] In one embodiment, please refer to Figures 2 to 5 The shielding device 100 includes a shielding barrel 1 and a lifting device 2. The lifting device 2 is connected to one end of the shielding barrel 1 along the height direction. The shielding barrel 1 is used to contain shielding liquid. With the lifting device 2 covered and fixed in the opening, the shielding barrel 1 is inserted into the radioactive pressure vessel 300. The lifting device 2 is used to connect with the hook 200.

[0031] For example, the shielding bucket 1 includes a bucket body 11 and a cover 12. The bucket body has a receiving cavity 11a and a connecting port communicating with the receiving cavity 11a. The receiving cavity 11a is used to contain shielding liquid, which can be water. The cover 12 can be fixed to the connecting port by sixteen M10 bolts.

[0032] The lifting device 2 can be a circular plate structure with a ring of second mounting holes 2a at its edge and a third mounting hole 2b near the edge for connection with the cover 12.

[0033] Here, by setting up a shielding container 1 and a lifting device 2, the shielding container 1 contains a shielding liquid, and the lifting device 2 is used for connection with the hook 200. In this way, during hoisting, the shielding container 1 located inside the radioactive pressure vessel 300 can further reduce radiation leakage at the opening, thereby reducing radiation damage to the operating environment and personnel.

[0034] For example, in one embodiment, the materials of the lifting device 2 and the shielding barrel 1 can be radiation shielding materials.

[0035] In one embodiment, please refer to Figure 3 and Figure 5 The shielding device 100 includes multiple shielding plates 3, which are stacked along the height direction and connected between the lifting device 2 and the shielding barrel 1.

[0036] For example, the shielding plate 3 can be made of steel plate and can be circular in shape.

[0037] For example, there can be two shielding plates 3, namely a first shielding plate 3a and a second shielding plate 3b. The first shielding plate 3 can be connected to the cover 12 by eight M16 bolts, and the second shielding plate 3b can be connected to the first shielding plate 3a by eight M16 bolts. The lifting device 2 can be connected to the second shielding plate 3b by eight M16 bolts.

[0038] This can further reduce the risk of radiation leakage.

[0039] In one embodiment, please refer to Figure 3 and Figure 5 The diameter of the shielding barrel 1 gradually decreases along the height direction away from the lifting device 2.

[0040] This facilitates the insertion and positioning of the shielding barrel 1 into the radioactive pressure vessel 300 via the opening guide.

[0041] In one embodiment, please refer to Figure 3 and Figure 4 The shielding device 100 is equipped with multiple rigging screws 4, which are arranged at intervals along the circumference of the radioactive pressure vessel 300.

[0042] For example, the lifting device 2 may be provided with a lifting lug 2c, which is connected to the rigging screw 4.

[0043] For example, the number of lifting lugs 2c and rigging screws 4 can both be four. The four lifting lugs 2c can be arranged at intervals along the circumference of the radioactive pressure vessel 300 on the lifting device 2. Then, one end of the four rigging screws 4 is connected to the four lifting lugs 2c, and the other end can be connected to the hook 200 through the locking rope.

[0044] The hoisting method includes: S21. Level the shielding device using a level and the screw rod of the rigging screw.

[0045] For example, the level can be a digital level.

[0046] Here, before lifting, the position of the shielding device 100 is adjusted by adjusting the screw rod of the rigging screw 4. At the same time, the level of the shielding device 100 is checked with a level to achieve leveling of the shielding device 100. This reduces the possibility of the shielding device 100 tilting during the lifting process, which could lead to the radioactive pressure vessel 300 colliding with other components in the reactor or the locking rope of the shielding device 100 breaking due to unbalanced force, thus improving the stability of the lifting.

[0047] In one embodiment, the step of aligning the hook 200 with the shielding device 100 includes: S22. Hang the laser plumb bob on the hook and adjust the hook so that the laser emitted by the laser plumb bob is aligned with the center position of the shielding device.

[0048] For example, after leveling, the laser plumb bob is hung on the hook 200. After the laser plumb bob is stable, the radial distance between it and the center position of the lifting device 2 is determined. Then, the hook 200 is adjusted according to the distance to achieve the centering of the shielding device 100 and the hook 200.

[0049] This can improve stability during subsequent hoisting processes.

[0050] In one embodiment, before S3, connecting the hook and the shielding device, and hoisting the radioactive pressure vessel to the designated location for cutting and dismantling, the hoisting method includes: S4. Perform a trial hoisting of the radioactive pressure vessel to confirm that there are no attachments on the outer periphery of the radioactive pressure vessel.

[0051] It should be noted that the internal structure of the reactor is relatively complex, which makes it easy for the reactor to get entangled or stuck by other structures when hoisting the radioactive pressure vessel 300, so that attachments can be hung on the outer surface of the radioactive pressure vessel 300.

[0052] The method to determine that there are no attachments on the outer periphery of the radioactive pressure vessel 300 can be determined by visual observation by the operator or by other equipment such as cameras.

[0053] Here, by conducting a trial lift before the formal lifting to ensure that there are no attachments on the outer periphery of the radioactive pressure vessel 300, the possibility of the shielding device 100 breaking during lifting and causing damage to other structures can be reduced.

[0054] In one embodiment, the hoisting method includes: S41. By installing a force gauge between the hook and the shielding device, and based on the measured value of the force gauge and the combined mass of the radioactive pressure vessel and the shielding device, it is determined whether there are any attachments on the outer periphery of the radioactive pressure vessel 300.

[0055] For example, the force gauge can be an electronic force gauge.

[0056] For example, after alignment, a force gauge can be connected between the hook 200 and the lifting device 2, and then the operator can return to the site. After slowly starting the lifting equipment to steadily raise the radioactive pressure vessel 300 by 20 cm, the force gauge readings are observed and recorded. Based on the combined mass of the radioactive pressure vessel 300 and the shielding device 100, it is determined whether there are any objects attached to the outer periphery of the radioactive pressure vessel 300.

[0057] The mass of the radioactive pressure vessel 300 and the shielding device 100 can be obtained from the relevant parameter table.

[0058] It should be noted that the mass of the radioactive pressure vessel 300 here refers to its mass before operation, i.e., the initial mass. The mass of the shielding device 100 can be obtained from the mass in the parameter table or by subsequent weighing.

[0059] Here, by measuring the actual mass of the radioactive pressure vessel 300 after trial hoisting and comparing it with the sum of the masses of the radioactive pressure vessel 300 and the shielding device 100, if the mass is greater than the sum of the masses, it indicates that the outer periphery of the radioactive pressure vessel 300 has a mounting object; the measured value can also be used to qualitatively determine whether the material of the irradiated radioactive pressure vessel 300 has aged severely and whether its tensile properties meet the hoisting requirements.

[0060] In one exemplary embodiment, the measured values ​​from the force gauge should be recorded after they have stabilized.

[0061] In one embodiment, if the measured value is less than 1.05 times the sum of the weights of the radioactive pressure vessel 300 and the shielding device 100, it is determined that there are no attachments on the outer periphery of the radioactive pressure vessel 300.

[0062] Here, by setting an appropriate error value, interference from factors such as the measurement accuracy of the force gauge, the temperature and humidity of the environment, and the minute residual radiation from the irradiated pressure vessel can be eliminated, making the judgment of the structure more accurate and reliable.

[0063] In one embodiment, the hoisting method includes: S43. After the radioactive pressure vessel is hoisted, it is kept in place for a set time to confirm that the radioactive pressure vessel does not deform within the set time.

[0064] For example, during the trial hoisting and stay for a set time, it is possible to determine whether the radioactive pressure vessel 300 is deformed through remote monitoring.

[0065] Here, by holding the test hoist for a set time and confirming that the radioactive pressure vessel 300 has no deformation, the subsequent hoisting requirements can be met, ensuring the safety and stability of the hoisting.

[0066] In one exemplary embodiment, during the trial hoisting process, after confirming that there are no attachments and no deformation, the radioactive pressure vessel 300 can be returned to the reactor core and removed.

[0067] In one exemplary embodiment, after the radioactive pressure vessel 300 is hoisted to the designated location, the shielding device 100 can be disassembled, awaiting the next step of cutting and dismantling.

[0068] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, and improvements made within the spirit and scope of this application are included within the scope of protection of this application.

Claims

1. A method for hoisting a radioactive pressure vessel, characterized in that, The radioactive pressure vessel, having an opening on one side along its height, is lifted using hoisting equipment and shielding devices. The hoisting method includes: The shielding device is placed over the opening and fixed in place. Level the shielding device and align the hook of the hoisting equipment with the shielding device; Connect the hook to the shielding device, and hoist the radioactive pressure vessel to the designated location for cutting and dismantling.

2. The hoisting method according to claim 1, characterized in that, The shielding device includes a shielding barrel and a lifting device. The lifting device is connected to one end of the shielding barrel along the height direction. The shielding barrel is used to contain shielding liquid. With the lifting device covered and fixed to the opening, the shielding barrel is inserted into the radioactive pressure vessel. The lifting device is used to connect to the hook.

3. The hoisting method according to claim 2, characterized in that, The shielding device includes multiple shielding plates, which are stacked along the height direction and connected between the lifting device and the shielding barrel.

4. The hoisting method according to claim 2, characterized in that, The diameter of the shielding barrel gradually decreases along the height direction towards the direction away from the lifting device.

5. The hoisting method according to claim 1, characterized in that, The shielding device is equipped with multiple rigging helical buckles, which are arranged at intervals along the circumference of the radioactive pressure vessel; the hoisting method includes: The shielding device is leveled using a spirit level and the screw rod of the rigging auger.

6. The hoisting method according to claim 1, characterized in that, The step of aligning the hook with the shielding device includes: Hang the laser plumb bob on the hook and adjust the hook so that the laser emitted by the laser plumb bob is aligned with the center of the shielding device.

7. The hoisting method according to claim 1, characterized in that, Before connecting the hook to the shielding device and hoisting the radioactive pressure vessel to the designated location for cutting and dismantling, the hoisting method includes: A trial hoisting was performed on the radioactive pressure vessel to confirm that there were no attachments on its outer perimeter.

8. The hoisting method according to claim 7, characterized in that, The hoisting method includes: By installing a force gauge between the hook and the shielding device, and based on the measured value of the force gauge and the combined mass of the radioactive pressure vessel and the shielding device, it can be determined whether there are any attachments on the outer periphery of the radioactive pressure vessel.

9. The hoisting method according to claim 8, characterized in that, If the measured value is less than 1.05 times the sum of the weights of the radioactive pressure vessel and the shielding device, then it is determined that there are no attachments on the outer periphery of the radioactive pressure vessel.

10. The hoisting method according to claim 7, characterized in that, The hoisting method includes: After the radioactive pressure vessel is hoisted and held for a set time, it is confirmed that the radioactive pressure vessel does not deform within the set time.

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