Spent fuel assembly storage unit dismounting device and process

Abstract

The invention relates to the technical field of spent fuel assembly dismantling, aims to solve the problems that a cadmium grillwork is high in process difficulty in underwater remote operation and does not have an autonomous operation process and tool, and discloses a spent fuel assembly storage unit dismantling device and a spent fuel assembly storage unit dismantling process, the device comprises a nut dismantling rod, a grabbing tool and a grabbing tool hanging frame, the nut dismounting rod is used for remotely dismounting nuts of the storage unit, the grabbing tool is provided with an upper buckle plate and a lower buckle plate, forms a lantern ring structure and is used for positioning a horn mouth of the storage unit, and a steel wire rope is arranged outside the grabbing tool and connected with one end of the electric hoist. The grabbing tool hanging frame is provided with a hanging point connected with the other end of the electric hoist. After the spent pool of the second-generation nuclear power station is transformed, the original old grillwork is disassembled and subjected to volume reduction, and preparation is made for later storage.

Description

Technical Field

[0001] The present invention relates to the technical field of spent fuel storage removal, and in particular to a spent fuel assembly storage unit removal device and process. Background Art

[0003] At the same time, the spent fuel reprocessing plant is currently unable to receive the spent fuel produced by various nuclear power plants. In order to improve the storage capacity of the spent fuel pool of the nuclear power plant, some power plants have carried out intensive transformation of storage racks based on the original spent fuel pool. When expanding and transforming the spent fuel pool, some cadmium grids that need to be replaced must be lifted out of the spent fuel pool and processed. Summary of the invention

[0004] The purpose of the present invention is to provide a spent fuel assembly storage unit dismantling device and process, so as to solve the problem that when a spent fuel pool of a nuclear power plant is expanded and renovated, the grid has high radioactivity after long-term storage of spent fuel, and must be remotely operated underwater, the operation process is difficult, and there is no autonomous operation process and tools. The present invention can realize the dismantling and replacement of the cadmium grid, thereby improving the storage capacity of the spent fuel pool.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] In one aspect, the present invention provides a spent fuel assembly storage unit dismantling device, comprising:

[0007] A nut removal rod, used for remotely removing the nut of the storage unit, the nut removal rod comprising a long rod, a sleeve arranged at the bottom of the long rod, and a guide plate arranged on the long rod;

[0008] A grabbing tool, which has an upper buckle plate and a lower buckle plate and forms a collar structure, and is used for positioning with the bell mouth of the storage unit, and a steel wire rope is provided on the outside of the grabbing tool, and the steel wire rope is connected to one end of the electric hoist; and

[0009] The grabbing tool rack has a hanging point connected to the other end of the electric hoist.

[0010] In some embodiments, two guide plates are provided on the long rod, one of which is arranged close to the sleeve, and the other is arranged close to the top of the long rod.

[0011] In some embodiments, one of the guide plates is located 300 mm away from the sleeve, and the two guide plates are spaced 3500 mm apart.

[0012] In some embodiments, the guide plate is an inverted cone-shaped structure.

[0013] In some embodiments, the maximum outer diameter of the guide plate is 221.9 mm to 222.1 mm.

[0014] In some embodiments, the long rod is a hollow rod, and its axial dimension is, for example, 4785 mm.

[0015] In some embodiments, a handle is provided on the long pole.

[0016] In some embodiments, the upper gusset plate is an L-shaped structure as a whole, with a positioning portion for installing a positioning pin at one end, and the positioning portion is located on the outside of the upper gusset plate; and a connecting portion is provided at the other end, and the connecting portion is located on the outside of the upper gusset plate;

[0017] The lower buckle plate is an L-shaped structure as a whole, and one end is provided with a positioning hole for the positioning pin to pass through, and the positioning hole is adapted to the positioning part so that the positioning pin passes through and fixedly connects the upper buckle plate and the lower buckle plate; the other end of the L-shaped structure is provided with a connecting hole, and the connecting hole is adapted to the connecting part so that the connecting bolt passes through and fixedly connects the upper buckle plate and the lower buckle plate.

[0018] In some embodiments, grooves are provided on the outside of the upper buckle plate and the lower buckle plate, and the steel wire rope is arranged in the groove, and the steel wire rope is used for remotely pulling and grabbing tools.

[0019] In some embodiments, the grabbing tool rack has a connecting beam and a counterweight, the connecting beam is connected to two vertical rods, a horizontal beam is provided between the two vertical rods, and the hanging point is provided on the horizontal beam.

[0020] In another aspect, the present invention provides a spent fuel assembly storage unit dismantling process, comprising:

[0021] Step 1: Remove the M64 nut from the storage unit;

[0022] Step 2: Install the crawler;

[0023] Step 3: Extract the storage unit using the grabbing tool.

[0024] In some embodiments, step 1 specifically includes:

[0025] Step 1.1: Lift the cadmium grid to an open area;

[0026] Step 1.2: inserting the nut removal rod into the storage unit, and the nut removal rod enters the storage unit through the guide plate at the bottom of the nut removal rod, so that the nut removal rod is inserted into the storage unit in a centered manner;

[0027] Step 1.3: Use the guide plate at the top of the nut removal rod to align the sleeve with the M64 nut, and operate the sleeve to completely cover the M64 nut at the center;

[0028] Step 1.4: Remotely rotate the handle slowly counterclockwise, and the long rod transmits power to drive the sleeve to rotate counterclockwise to loosen the M64 nut;

[0029] Step 1.5: After the M64 nut is completely loosened, the M64 nut falls into the sleeve, and the support shaft of the sleeve prevents the M64 nut from falling out of the sleeve;

[0030] Step 1.6: Pull the nut removal rod together with the M64 nut in the sleeve out of the storage unit, and take out and collect the M64 nut in the sleeve;

[0031] Step 1.7: Repeat steps 1.2 to 1.6 to remove the remaining M64 nuts in the storage unit of the cadmium grid.

[0032] In some embodiments, step 2 specifically includes:

[0033] Step 2.1: Lift the grab tool rack to an open location;

[0034] Step 2.2: Check that the counterweight and the grab tool bracket are firmly connected;

[0035] Step 2.3: Connect one end of the electric hoist to the hanging point.

[0036] In some embodiments, step 3 specifically includes:

[0037] Step 3.1: disassemble the upper buckle plate and the lower buckle plate of the grabbing tool, and then insert them into the lower part of the bell mouth of the storage unit;

[0038] Step 3.2: Connect the positioning pins and connecting bolts to the upper buckle plate and the lower buckle plate to ensure that the grabbing tool completely clamps the bell mouth position;

[0039] Step 3.3: Connect the wire rope to the other end of the electric hoist;

[0040] Step 3.4: Start the electric hoist to drive the wire rope to slowly pull out the storage unit;

[0041] Step 3.5: Repeat steps 3.1 to 3.4 to pull out the remaining storage units of the cadmium rack until the storage units of the entire cadmium rack are completely removed.

[0042] Compared with the prior art, the spent fuel assembly storage unit dismantling device and process provided by the present invention has the following beneficial effects:

[0043] The present invention realizes the dismantling and reducing of the original old grid after the spent pool of the second-generation nuclear power plant is renovated, so as to prepare for the later storage. The storage unit can be quickly dismantled by the present invention, which provides the prerequisite for the dismantling of the cadmium grid and lays the foundation for the dismantling of the cadmium grid when the spent pool of the second-generation nuclear power plant is renovated or decommissioned.

[0044] The present invention independently designs, for the first time, a device and a process method for removing cadmium grids in a spent fuel pool, which can realize the treatment of old grids in the spent fuel pool transformation, expansion and future decommissioning work. Through an independently designed remote operation device (including the nut removal rod, grabbing tools and related hangers and other ancillary equipment of the present invention, i.e., a spent fuel assembly storage unit removal device), long-distance underwater operation of the old grids is realized, thereby realizing the rapid removal of the storage units in the spent fuel pool.

[0045] At the same time, with the increase of operating years, the present invention has promotion and technology conversion value for the dismantling of cadmium grids during the transformation or decommissioning of spent pools of early nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for the technical description.

[0047] Figure 1 This is a schematic diagram of the structure of the cadmium grid in the spent pool of a nuclear power plant;

[0048] Figure 2 A main sectional view of a nut removal rod provided by the present invention;

[0049] Figure 3 A main cross-sectional view of the grabbing tool provided by the present invention;

[0050] Figure 4 A top view of the grabbing tool provided by the present invention;

[0051] Figure 5 A front view of the grabbing tool rack provided by the present invention;

[0052] Figure 6 A right side view of the grabbing tool rack provided by the present invention;

[0053] Figure 7 The present invention provides a flow chart of the spent fuel assembly storage unit dismantling process.

[0054] Description of reference numerals:

[0055] 1. Sleeve; 2. Long rod; 3. Fastening bolt; 4. Gasket; 5. Guide plate; 6. Handle; 7. Leg; 8. Bottom plate; 9. Storage unit; 10. Enclosure; 11. Top plate; 12. Locating pin; 13. Lower buckle plate; 14. Upper buckle plate; 15. Wire rope; 16. Connecting bolt; 17. Connecting beam; 18. Counterweight; 19. Hanging point. DETAILED DESCRIPTION

[0056] The following is further explained in detail through specific implementation methods.

[0057] For ease of understanding, a brief introduction to the cadmium grid is first given. Figure 1 As shown, the cadmium grid belongs to the existing equipment and is the operating object of the present invention. The size of the cadmium grid is 4425mm×1840mm×1840mm and the weight is about 8t. The cadmium grid is composed of 4 enclosures 10, 1 bottom plate 8, 1 top plate 11, 20 legs 7, and 36 storage units 9. The storage unit 9 is inserted into the cadmium grid through the top plate 11 and connected to the bottom plate 8 through the M64 nut. The spent fuel pool storage grid is a cadmium grid with high radioactivity. In order to reduce the volume of radioactive waste and provide a prerequisite for the disintegration of the cadmium grid, the original cadmium grid unit must be disassembled.

[0058] The present invention takes the spent fuel storage grid of the second-generation nuclear power plant as input conditions, and specially designs a set of spent fuel assembly storage unit removal device and process method. The present invention independently innovates and designs the removal device and process method for the first time, which is suitable for the removal of spent fuel storage grids. For the removal of the grids, remote operation can be achieved, and the storage units in the spent fuel pool can be quickly removed, providing space and prerequisites for the dismantling of the cadmium grids, laying the foundation for the dismantling of the cadmium grids during the renovation or decommissioning of the spent pools of the second-generation nuclear power plants.

[0059] On the one hand, if Figures 2 to 6 As shown, the present invention provides a spent fuel assembly storage unit removal device, which includes a nut removal rod, a grabbing tool, and a grabbing tool rack. The nut removal rod is used alone to remotely remove the nut of the storage unit 9. After the nut is removed, the grabbing tool is used to take the storage unit 9 out of the cadmium grid. After the grabbing tool is used, it is fixed to the grabbing tool rack through the hanging point 19.

[0060] like Figure 2 As shown, the nut removal rod includes a sleeve 1, a long rod 2, a fastening bolt 3, a gasket 4, a guide plate 5, and a handle 6. The nut removal rod is operated to penetrate into the storage unit 9, so that the sleeve 1 reaches the bottom of the storage unit 9 and covers the M64 connection nut at the center, and then the guide plate 5 is rotated counterclockwise to drive the M64 connection nut to rotate, thereby realizing the remote removal of the M64 connection nut.

[0061] The long rod 2 is a hollow rod, and its axial dimension is, for example, 4785 mm. This length enables the sleeve 1 to completely reach the M64 connecting nut position at the bottom of the storage unit while ensuring the operating position of the top guide plate 5.

[0062] A sleeve 1 is installed at one end of the long rod 2. The sleeve 1 is an internal hexagonal cylindrical female head structure with an E-shaped cross section. The advantage is that it can quickly and accurately find the position of the M64 connecting nut and cover the male head of the nut.

[0063] At least one guide plate 5 is installed on the long rod 2. The guide plate 5 is an inverted cone-shaped structure, and its cone surface plays a centering and guiding role when entering the storage unit 9, so that the tool can be inserted into the storage unit 9 in a centering manner.

[0064] The maximum outer diameter of the guide plate 5 is 221.9 mm to 222.1 mm, which is close to the inner size of the storage unit 9 and leaves enough clearance, so as to play a role of safety guidance.

[0065] The guide plate 5 has a guiding function, and the nut removal rod can be smoothly inserted into the storage unit 9 through the guide plate 5, so that the sleeve 1 and the M64 nut can be easily aligned, and then the M64 nut can be quickly removed.

[0066] The guide plate 5 is fixedly mounted on the long rod 2 by means of the fastening bolts 3. The fastening bolts 3 are made of stainless steel hexagon socket bolts. The gasket 4 is sleeved on the fastening bolts 3 and tightened on the mounting holes of the long rod 2. The gasket 4 serves to increase the pre-tightening force of the bolts so that the fastening bolts 3 will not fall off the long rod 2.

[0067] The guide plate 5 is installed near the sleeve 1, about 300 mm away from the sleeve 1, to prevent the long rod 2 from penetrating into the storage unit 9 and bending. The lag of the guide plate 5 causes the guide centering function to fail.

[0068] Preferably, two guide plates 5 are installed on the long rod 2. The two guide plates 5 are spaced 3500 mm apart. This distribution pattern plays a guiding and centering role at the bottom and top positions of the nut removal rod at the same time. The double guide makes the centering effect of the long rod 2 better, and can make the sleeve 1 accurately reach the center M64 connecting nut position.

[0069] A handle 6 is provided through the upper part of the long rod 2, and the diameter of the handle 6 is 12 mm. A person can remotely rotate the handle 6 counterclockwise to drive the bottom sleeve 1 of the tool to rotate counterclockwise, thereby realizing rapid disassembly of the M64 connecting nut.

[0070] Preferably, the handle 6 is arranged at a position 100 mm away from the top of the long rod 2. This position can maximize the rotation torque of the handle and facilitate operation.

[0071] like Figure 3 and Figure 4As shown, the grabbing tool includes a positioning pin 12 , an upper buckle plate 13 , a lower buckle plate 14 , a steel wire rope 15 , and a connecting bolt 16 .

[0072] The grabbing tool can be positioned with the bell mouth of the storage unit, and the upper buckle plate 13 and the lower buckle plate 14 can be quickly disassembled to achieve positioning with the storage unit 9.

[0073] The grabbing tool is a square plate-shaped structure as a whole, with dimensions of 271.5 mm×271.5 mm×40 mm. The grabbing tool is a ring structure formed by connecting an upper buckle plate 13 and a lower buckle plate 14 through a positioning pin 12 and a connecting bolt 16, which can cover the bell mouth of the storage unit 9.

[0074] like Figure 3 and Figure 4 As shown, the cross-sectional shape of the grasping tool is a square, and the size is 271.5 mm×271.5 mm, which is consistent with the size of the bell mouth of the storage unit 9, and grasping is achieved by covering the bell mouth.

[0075] One end of the upper gusset plate 13 and the lower gusset plate 14 are fixedly connected by the positioning pin 12, and the other end is fixedly connected by the connecting bolt 16. The positioning pin 12 passes through the lower gusset plate 14 and enters the positioning part on the outer side of the upper gusset plate 13 to complete the fixed connection. The connecting bolt 16 passes through the lower gusset plate 14 and enters the connecting part on the outer side of the upper gusset plate 13 to complete the fixed connection.

[0076] The outer sides of the upper buckle plate 13 and the lower buckle plate 14 are both provided with grooves, and steel wire ropes 15 are arranged in the grooves. The steel wire ropes 15 are used for remotely pulling out the grabbing tool. After the grabbing tool covers the storage unit 9, the storage unit 9 can be pulled out of the cadmium grid by connecting the electric hoist to drive the steel wire ropes 15 on both sides.

[0077] Preferably, the number of the grooves is 4 and they are all arranged in the middle of each side of the gripping tool.

[0078] The upper buckle plate 13 is an L-shaped structure as a whole. One end of the L-shaped structure is provided with a positioning portion for installing the positioning pin 12, and the positioning portion is located outside the upper buckle plate 13; the other end of the L-shaped structure is provided with a connecting portion, and the connecting portion is located outside the upper buckle plate 13.

[0079] The lower buckle plate 14 is an L-shaped structure as a whole. A positioning hole for the positioning pin 12 to pass through is provided at one end of the L-shaped structure. The positioning hole is adapted to the positioning portion so that the positioning pin 12 passes through and fixedly connects the upper buckle plate 13 and the lower buckle plate 14. A connecting hole is provided at the other end of the L-shaped structure. The connecting hole is adapted to the connecting portion so that the connecting bolt 16 passes through and fixedly connects the upper buckle plate 13 and the lower buckle plate 14.

[0080] like Figure 5 and Figure 6As shown, the grab tool rack includes 16 connecting beams 17, a set of counterweights 18, and hanging points 19. The grab tool rack provides a connection point for the electric hoist and fixes the electric hoist. The other end of the electric hoist is connected to the grab tool wire rope 15. The electric hoist drives the grab tool to provide power for extracting the storage unit 9.

[0081] The connecting beam 17 is arranged at the bottom, and two vertical rods are connected to the connecting beam 17, a cross beam is arranged between the two vertical rods, and a hanging point 19 is arranged on the cross beam. A counterweight 18 is placed on the connecting beam 17, and the counterweight 18 is used to keep balance with the power of the grabbing tool to prevent the rack from tipping over.

[0082] The hanging point 19 can be adjusted up and down and left and right. The hanging point 19 is connected to the electric hoist. The grab tool rack provides a connection point for the electric hoist and fixes the electric hoist. The electric hoist provides power for extracting the storage unit.

[0083] On the other hand, the present invention also provides a spent fuel assembly storage unit dismantling process, comprising:

[0084] Step 1: Remove the M64 nut of the storage unit 9. Specifically include:

[0085] Step 1.1: Lift the cadmium grid to an open area;

[0086] Step 1.2: Insert the nut removal rod into the storage unit 9. The guide plate 5 at the bottom of the nut removal rod serves as a centering guide when the nut removal rod enters the storage unit 9, so that the nut removal rod is inserted into the storage unit 9 in a centering manner.

[0087] Step 1.3: Use the guide plate 5 (another guide plate 5) at the top of the nut removal rod to align the sleeve 1 of the removal rod with the M64 nut, and operate the sleeve 1 to completely cover the M64 nut at the center;

[0088] Step 1.4: Remotely rotate the handle 6 slowly counterclockwise, and the long rod 2 transmits power to drive the sleeve 1 to rotate counterclockwise to loosen the M64 nut;

[0089] Step 1.5: After the M64 nut is completely loosened, the M64 nut falls into the sleeve 1. There is a support shaft in the sleeve 1 to prevent the M64 nut from falling out of the sleeve 1.

[0090] Step 1.6: Pull the nut removal rod together with the M64 nut in the sleeve 1 out of the storage unit 9, and take out the M64 nut in the collection sleeve 1;

[0091] Step 1.7: Repeat steps 1.2 to 1.6 to remove the M64 nuts in the remaining storage units 9 of the cadmium grid.

[0092] Step 2: Install the crawler. This includes:

[0093] Step 2.1: Lift the grab tool rack to an open location;

[0094] Step 2.2: Check that the counterweight 18 is firmly connected to the grab tool bracket;

[0095] Step 2.3: Connect one end of the electric hoist to the hanging point 19.

[0096] Step 3: Extract the storage unit 9 by using a grabbing tool. Specifically including:

[0097] Step 3.1: Disassemble the upper buckle plate 13 and the lower buckle plate 14 of the grabbing tool, and then insert them into the lower part of the bell mouth of the storage unit 9;

[0098] Step 3.2: Connect the positioning pin 12 and the connecting bolt 16 with the upper buckle plate 13 and the lower buckle plate 14 to ensure that the grabbing tool completely clamps the bell mouth position of the storage unit 9;

[0099] Step 3.3: Connect the wire rope 15 to the other end of the electric hoist;

[0100] Step 3.4: Start the electric hoist to drive the wire rope 15 to slowly pull out the storage unit 9;

[0101] Step 3.5: Repeat steps 3.1 to 3.4 to pull out the remaining storage units 9 of the cadmium grid until the entire grid storage unit 9 is removed.

[0102] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A spent fuel assembly storage unit dismantling device, characterized in that: include: A nut removal rod, used for remotely removing the nut of the storage unit (9), the nut removal rod comprising a long rod (2), a sleeve (1) arranged at the bottom of the long rod (2), and a guide plate (5) arranged on the long rod (2); A grabbing tool having an upper buckle plate (13) and a lower buckle plate (14) forming a collar structure for positioning with the bell mouth of the storage unit (9); a steel wire rope (15) is provided on the outside of the grabbing tool, and the steel wire rope (15) is connected to one end of the electric hoist; and The grabbing tool hanger has a hanging point (19) connected to the other end of the electric hoist.

2. The spent fuel assembly storage unit dismantling device according to claim 1, characterized in that: The long rod (2) is provided with two guide plates (5), one of which is arranged close to the sleeve (1) and the other is arranged close to the top of the long rod (2).

3. The spent fuel assembly storage unit dismantling device according to claim 1, characterized in that: The guide plate (5) is an inverted cone-shaped structure.

4. The spent fuel assembly storage unit dismantling device according to claim 1, characterized in that: The long rod (2) is provided with a handle (6).

5. The spent fuel assembly storage unit dismantling device according to claim 1, characterized in that: The upper buckle plate (13) is an L-shaped structure as a whole, with one end provided with a positioning portion for installing the positioning pin (12), the positioning portion being located on the outside of the upper buckle plate (13); and the other end provided with a connecting portion, the connecting portion being located on the outside of the upper buckle plate (13); The lower buckle plate (14) is an L-shaped structure as a whole, and one end is provided with a positioning hole for the positioning pin (12) to pass through, and the positioning hole is adapted to the positioning portion so that the positioning pin (12) passes through and fixedly connects the upper buckle plate (13) and the lower buckle plate (14); the other end of the L-shaped structure is provided with a connecting hole, and the connecting hole is adapted to the connecting portion so that the connecting bolt (16) passes through and fixedly connects the upper buckle plate (13) and the lower buckle plate (14).

6. The spent fuel assembly storage unit dismantling device according to claim 1, characterized in that: The grabbing tool hanger has a connecting beam (17) and a counterweight (18), the connecting beam (17) is connected to two vertical rods, a horizontal beam is arranged between the two vertical rods, and the hanging point (19) is arranged on the horizontal beam.

7. A spent fuel assembly storage unit dismantling process, characterized in that: include: Step 1: Remove the M64 nut of the storage unit (9); Step 2: Install the crawler; Step 3: Extract the storage unit (9) using the grabbing tool.

8. The spent fuel assembly storage unit dismantling process according to claim 7, characterized in that: Step 1 specifically includes: Step 1.1: Lift the cadmium grid to an open area; Step 1.2: inserting the nut removal rod into the storage unit (9), and allowing the nut removal rod to enter the storage unit (9) through the guide plate (5) at the bottom of the nut removal rod, so that the nut removal rod is inserted into the storage unit (9) in a centered manner; Step 1.3: Use the guide plate (5) at the top of the nut removal rod to align the sleeve (1) with the M64 nut, and operate the sleeve (1) to completely cover the M64 nut at the center; Step 1.4: The handle (6) is slowly rotated counterclockwise remotely, and the long rod (2) transmits power to drive the sleeve (1) to rotate counterclockwise, thereby loosening the M64 nut; Step 1.5: After the M64 nut is completely loosened, the M64 nut falls into the sleeve (1), and the support shaft of the sleeve (1) prevents the M64 nut from falling out of the sleeve (1); Step 1.6: Pull the nut removal rod together with the M64 nut in the sleeve (1) out of the storage unit (9), and take out and collect the M64 nut in the sleeve (1); Step 1.7: Repeat steps 1.2 to 1.6 to remove the remaining M64 nuts in the storage unit (9) of the cadmium grid.

9. The spent fuel assembly storage unit dismantling process according to claim 7, characterized in that: Step 2 specifically includes: Step 2.1: Lift the grab tool rack to an open location; Step 2.2: Check that the counterweight (18) is firmly connected to the grab tool bracket; Step 2.3: Connect one end of the electric hoist to the hanging point (19).

10. The spent fuel assembly storage unit dismantling process according to claim 7, characterized in that: Step 3 specifically includes: Step 3.1: disassemble the upper buckle plate (13) and the lower buckle plate (14) of the grabbing tool, and then insert them into the lower part of the bell mouth of the storage unit (9); Step 3.2: Connect the positioning pin (12) and the connecting bolt (16) to the upper buckle plate (13) and the lower buckle plate (14), and ensure that the grabbing tool completely clamps the bell mouth position; Step 3.3: Connect the wire rope (15) to the other end of the electric hoist; Step 3.4: Start the electric hoist to drive the steel wire rope (15) to slowly pull out the storage unit (9); Step 3.5: Repeat steps 3.1 to 3.4, and pull out the remaining storage units (9) of the cadmium rack, until the removal of the storage units (9) of the entire cadmium rack is completed.

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