Loader

Abstract

The utility model relates to a loader, the loader comprises: a bearing main body comprising a left side plate, a right side plate, a rear side plate, a front side plate and a bottom plate, the left side plate, the right side plate, the rear side plate and the front side plate are respectively connected with the bottom plate and enclose to form a rectangular box body with openings at the top and the front part, and the rectangular box body is used for accommodating a fuel assembly to be transferred; the guide wheels are symmetrically mounted at the ends, close to the tops, of the left side plate and the right side plate; the hinge shafts are symmetrically mounted at the ends, close to the bottoms, of the left side plate and the right side plate; the bearing main body is mounted on the transfer trolley through a hinge shaft and rotates around the axis of the hinge shaft so as to realize conversion between a vertical position and a horizontal position; the anti-toppling device is installed on the side, close to the front opening, of the left side plate and / or the right side plate, located at the end close to the top and used for preventing the to-be-transferred fuel assembly from falling out of the front opening together with the front side plate. The loader structure solves the problem that the efficiency of loading the fuel assembly into the loader and taking the fuel assembly out of the loader is low.

Description

Technical Field

[0001] This utility model relates to nuclear power plant core fuel assembly refueling technology, and in particular to a carrier suitable for pressurized water reactor nuclear power plants. Background Technology

[0002] Nuclear power generation, as a clean energy source that does not produce greenhouse gases, is receiving increasing attention. Pressurized water reactor nuclear power plants, as a typical representative of nuclear power generation technology, have high power generation efficiency and fuel utilization rate, reducing energy waste, and are therefore widely used.

[0003] During the operation of a pressurized water reactor (PWR) nuclear power plant, the fuel assemblies in the reactor core continuously burn and are converted into spent fuel assemblies. To ensure the normal operation of the nuclear power plant, it is necessary to periodically shut down the reactor and replace the fuel assemblies. The reactor core is located in the reactor building (RX side), while the fuel assemblies to be installed and the spent fuel assemblies removed from the core are stored in the fuel building (KX side). The reactor building and the fuel building are isolated by a thick containment wall. The fuel assembly transfer device, as a key piece of equipment for replacing fuel assemblies during nuclear power plant shutdowns, is mainly used to transfer fuel assemblies between the reactor building and the fuel building, playing a vital role in the refueling process of a PWR nuclear power plant.

[0004] Currently, most pressurized water reactor nuclear power plants use fuel assembly transfer devices. After the carrier in the trolley moves into place along with the transport trolley, the tilting frame takes the carrier and completes the tilting. The carrier tilts to a vertical position, and the fuel assembly is vertically loaded into the carrier from the top, completing the transfer. Existing technology requires the installation of two tilting frames in the reactor building and fuel building respectively, equipped with corresponding motors and transmission mechanisms to drive steel cables to complete the tilting operation of the carrier in the reactor building and fuel building. This results in high cost of the transfer device, and the control program is complex due to the need for coordination of multiple control units, making the system difficult to maintain and operate. The tilting of the carrier uses a single-axis steel cable pulling method, which has low reliability. If the steel cable is accidentally damaged, the fuel assembly is prone to falling. At the same time, the gap between the side wall of the carrier and the fuel assembly is only 5mm. The fuel assembly, which is more than 4 meters long, is vertically inserted and removed from the top of the carrier. Due to the narrow gap, the fuel assembly is easily scratched during the operation. In order to reduce the risk of damage to the fuel assembly due to scratching, the speed of inserting and removing the fuel assembly from the carrier is usually limited, resulting in low efficiency of fuel assembly insertion and removal. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a carrier in response to the above-mentioned defects of the prior art.

[0006] To achieve the above objectives, this utility model provides a carrier, comprising:

[0007] The supporting body includes a left side plate, a right side plate, a rear side plate, a front side plate, and a bottom plate. The left side plate, the right side plate, the rear side plate, and the front side plate are respectively connected to the bottom plate and form a rectangular box with an opening at the top and the front. The rectangular box houses the fuel assembly to be transferred.

[0008] Guide wheels are symmetrically installed at the top ends of the left and right side plates;

[0009] A hinge shaft is symmetrically mounted on one end of the left and right side plates near the bottom; the supporting body is mounted on a transfer trolley via the hinge shaft and rotates around the axis of the hinge shaft to switch between vertical and horizontal positions; and

[0010] An anti-tipping device is installed on the side of the left and / or right side panels near the front opening and at the top end. The anti-tipping device, together with the front side panels, prevents the fuel assembly to be transferred from falling out of the front opening.

[0011] The aforementioned load-bearing device includes:

[0012] The limiting plates are symmetrically installed on the left and right side plates respectively by fixing blocks, and the limiting plates have an open position and a retracted position relative to the fixing blocks;

[0013] A transmission mechanism includes an upper pull rod, a lower pull rod, and a pull rod reset component. The two ends of the upper pull rod are respectively connected to the limiting plate and the lower pull rod, and the pull rod reset component is connected to both the upper pull rod and the lower pull rod.

[0014] A control mechanism is disposed on the base plate and connected to the transmission mechanism. The control mechanism controls the limiting plate to switch between the open position and the retracted position.

[0015] The aforementioned carrier, wherein the control mechanism includes a base, a support block, and a base reset component; the rear end of the base is hinged to the base plate; the support block is mounted on the base plate corresponding to the front end of the base; the base reset component is located between the base and the base plate; the lower end of the pull rod is connected to the base and, together with the base reset component, drives the base to swing up and down around the hinge point; the base has a pressed position and a released position relative to the base plate; when the base is in the pressed position, the limiting plate switches to the open position; when the base is in the released position, the limiting plate switches to the retracted position.

[0016] In the aforementioned carrier, the base reset component is a base spring, which is located at the middle of the front part of the base plate and abuts against the base.

[0017] In the aforementioned carrier, the distance from the limiting plate to the top of the carrier body is 3% to 4% of the height of the carrier body.

[0018] The aforementioned load-bearing device further includes multiple reinforcing ribs arranged in parallel on the outer surfaces of the left side plate, rear side plate, and right side plate. The reinforcing ribs prevent expansion and deformation at the front opening of the load-bearing body.

[0019] In the aforementioned load-bearing device, the reinforcing rib is a U-shaped integral structural component.

[0020] In the aforementioned load-bearing device, the distribution density of the reinforcing ribs is adapted to the deformation degree at the opening of the load-bearing body during the flipping process of the load-bearing device, and the spacing between adjacent reinforcing ribs located at the upper and middle parts of the load-bearing body is smaller than the spacing located at the lower part of the load-bearing body.

[0021] In the aforementioned carrier, guide bevels are provided at the top and front openings of the carrier body.

[0022] In the aforementioned carrier, the left side plate, right side plate, and rear side plate are of equal height, and the height of the front side plate is 3% to 5% of the height of the rear side plate.

[0023] The technical advantages of this utility model are as follows:

[0024] This invention features a simply supported carrier structure with strong constraints, making it more reliable than single-axis structures and eliminating the risk of fuel assembly falling. Furthermore, this carrier structure solves the problem of low efficiency in loading and unloading fuel assemblies. The fuel assembly descends from an open position on the outside of the carrier, free from any objects that could cause it to scrape against the surrounding structure. Therefore, the fuel assembly can descend and rise rapidly. Only during the initial stage after entering the carrier does the speed need to be controlled to avoid scraping against the sides of the carrier body; that is, only 3% to 5% of its total length requires a slow descent, significantly reducing the time required for descent and retraction. Both the entry and exit of the fuel assembly from the carrier are achieved through translation, resulting in short distances and less time spent, effectively improving the efficiency of fuel assembly loading and unloading.

[0025] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the carrier structure according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the supporting main structure according to an embodiment of the present utility model;

[0028] Figure 3A This is a schematic diagram of the installation of an anti-tipping device according to an embodiment of the present invention;

[0029] Figure 3B for Figure 3A A magnified view of a portion of the image;

[0030] Figure 4 This is a schematic diagram of a fuel assembly according to an embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of a carrier being fitted with a fuel assembly according to an embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of the fuel assembly removal device of a carrier according to an embodiment of the present invention.

[0033] Among them, the attached reference numerals

[0034] 1. Supporting Body

[0035] 11 Left side panel

[0036] 12 right side panel

[0037] 13 rear side panels

[0038] 14 Front side panels

[0039] 15 base plate

[0040] 16 guide angle

[0041] 2 Anti-tipping device

[0042] 21 limit plate

[0043] 22 fixed blocks

[0044] 23 Upper pull rod

[0045] 24 pull rod reset component

[0046] 25 pull rod

[0047] 26 hinge blocks

[0048] 27 support blocks

[0049] 28 bases

[0050] 29 Base Reset Part

[0051] 3 guide wheels

[0052] 4 reinforcing ribs

[0053] 5 hinge shafts

[0054] 6 fuel assembly

[0055] 61 Upper tube seat

[0056] 62 lower tube seat

[0057] 7 lifting tools Detailed Implementation

[0058] The structural and working principles of this utility model will be described in detail below with reference to the accompanying drawings:

[0059] See Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the carrier structure according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of the supporting body 1 according to an embodiment of the present invention. The supporting device of the present invention includes: a supporting body 1, including a left side plate 11, a right side plate 12, a rear side plate 13, a front side plate 14, and a bottom plate 15. The left side plate 11, right side plate 12, rear side plate 13, and front side plate 14 are respectively connected to the bottom plate 15 and form a rectangular box with an opening at the top and front. The rectangular box is used to accommodate the fuel assembly 6 to be transferred. Guide angles 16 are provided at the top and front opening of the supporting body 1 to facilitate the entry of the fuel assembly 6 and the lifting device 7. The left side plate 11, right side plate 12, and rear side plate 13 are of equal height, and the height of the front side plate 14 is 3% to 5% of the height of the rear side plate 13, preferably the front side plate 14. The height of the side plate 14 is twice the height of the lower tube seat 82 of the fuel assembly 6; guide wheels 3 are symmetrically installed on the left side plate 11 and the right side plate 12 near the top; hinge shafts 5 are symmetrically installed on the left side plate 11 and the right side plate 12 near the bottom; the carrying body 1 is mounted on the transfer trolley via the hinge shafts 5 and rotates around the axis of the hinge shafts 5 to achieve conversion between vertical and horizontal positions; and an anti-tipping device 2 is installed on the side of the left side plate 11 and / or the right side plate 12 near the front opening and located at the top end, for use together with the front side plate 14 to prevent the fuel assembly 6 to be transferred from falling out of the front opening.

[0060] This embodiment also includes multiple reinforcing ribs 4, arranged parallel to the outer surfaces of the left side plate 11, rear side plate 13, and right side plate 12, to prevent expansion and deformation at the front opening of the load-bearing body 1, improve the rigidity of the load-bearing device, and effectively protect the fuel assembly 6 during transport. The reinforcing ribs 4 are preferably U-shaped integral structural components. The distribution of the reinforcing ribs 4 can be determined according to the degree of deformation at the opening of the load-bearing body 1 during the load-bearing device's flipping process. The reinforcing ribs 4 are more densely distributed in the upper and middle areas of the load-bearing body 1, while their distribution in other areas is sparser. That is, the distribution density of the reinforcing ribs 4 matches the degree of deformation at the opening of the load-bearing body 1 during the load-bearing device's flipping process. The spacing between adjacent reinforcing ribs 4 in the upper and middle parts of the load-bearing body 1 is smaller than the spacing in the lower part of the load-bearing body 1. When the load-bearing device is in a horizontal state, the U-shaped bottom of the reinforcing ribs 4 contacts the bottom plate 15 of the vehicle body. The weight of the load-bearing device and the internal fuel assembly 6 directly acts on the transport trolley. The rear side plate of the transport trolley can prevent the fuel assembly 6 from escaping from the load-bearing device when it is in a horizontal state.

[0061] See Figure 3A and Figure 3B , Figure 3A This is a schematic diagram of the installation of the anti-tipping device 2 according to an embodiment of the present invention. Figure 3B for Figure 3A A partial enlarged view. The anti-tipping device 2 of this embodiment includes: a limiting plate 21, symmetrically mounted on the left side plate 11 and the right side plate 12 respectively by fixing blocks 22. The fixing blocks 22 are symmetrically arranged and mounted on the left side plate 11 and the right side plate 12. Preferably, the limiting plate 21 and the fixing blocks 22 are close to the guide wheel 3 and located above the guide wheel 3, or located at the middle position between the guide wheel 3 and the top of the bearing body 1. The limiting plate 21 is provided with two holes, one hole is hinged to the fixing block 22, and the other hole is hinged to the upper pull rod 23. The limiting plate 21 has an open position and a retracted position relative to the fixing block 22. The distance from the limiting plate 21 to the top of the bearing body 1 is a certain percentage of the height of the bearing body 1. 3% to 4%, preferably the limiting plate 21 is located at the middle position of the upper pipe seat 61 of the corresponding fuel assembly 6; the transmission mechanism includes an upper pull rod 23, a lower pull rod 25 and a pull rod reset member 24, the two ends of the upper pull rod 23 are respectively connected to the limiting plate 21 and the lower pull rod 25, the pull rod reset member 24 is respectively connected to the upper pull rod 23 and the lower pull rod 25, the pull rod reset member 24 is preferably a pull rod spring, the lower pull rod 25 passes through the holes on the pull rod spring and the reinforcing rib 4, one end is hinged to the upper pull rod 23 and the other end is hinged to the base 28; and a control mechanism is set on the base plate 15 and connected to the transmission mechanism, used to control the limiting plate 21 to switch between the open position and the retracted position.

[0062] In this embodiment, the control mechanism includes a base 28, a support block 27, and a base reset component 29. The rear end of the base 28 is hinged to the base plate 15 via a hinge block 26, which is mounted on the base plate 15. The base 28 is hinged to the hinge block 26, allowing the base 28 to rotate around the hinge point. The support block 27 is mounted on the base plate 15 corresponding to the front end of the base 28. Preferably, there are two hinge blocks 26 and two support blocks 27, respectively mounted at the four corners of the base plate 15. The base reset component 29 is located between the base 28 and the base plate 15. Preferably, the base reset component 29 is located at the base. A seat spring is located at the midpoint of the base 28 and the base plate 15 near the front. Under the action of the seat spring, the base 28 can swing up and down around the hinge point. The lower end of the pull rod 25 is connected to the base 28 and, together with the base reset member 29, drives the base 28 to swing up and down around the hinge point. The base 28 has a pressed position and a released position relative to the base plate 15. When the base 28 is in the pressed position, the limiting plate 21 switches to the open position; when the base 28 is in the released position, the limiting plate 21 switches to the retracted position. The fuel assembly 6 is placed on the base 28, and the limiting plate 21 swings out to the open position to prevent it from tipping over. When the fuel assembly 6 is lifted, the limiting plate 21 automatically resets to the retracted position under the action of the control mechanism. The swinging out and retraction of the limiting plate 21 is achieved in a passive manner through a mechanical structure, which is simple, safe and reliable.

[0063] During operation, the KX-side tilting track enables the carrier to switch between horizontal and vertical positions within the fuel building. The RX-side tilting track enables the carrier to switch between horizontal and vertical positions within the reactor building. The RX-side mounting frame, near the fuel building, has upper and lower limit beams. When the carrier tilts to the vertical position, its bottom surface contacts these beams, mechanically stopping the transfer trolley. This mechanical stopping of the transfer trolley is sensorless, low-cost, and highly reliable, effectively preventing the risk of the transfer trolley exceeding its limits and damaging fuel assembly 6. The carrier tilting mechanism is a simply supported structure with strong constraints, making it more reliable than a single-axis tilting structure, and preventing fuel assembly 6 from falling.

[0064] See Figures 4-6 , Figure 4 This is a schematic diagram of a fuel assembly 6 according to an embodiment of the present invention. Figure 5 This is a schematic diagram of the carrier being fitted with the fuel assembly 6 according to an embodiment of the present invention. Figure 6This is a schematic diagram of removing the fuel assembly 6 from the carrier according to an embodiment of the present invention. When loading the carrier, the carrier is positioned vertically, and the lifting device 7 is used to lift the fuel assembly 6 and rapidly lower it to near the upper edge of the front side plate 14 of the carrier. The fuel assembly 6 is then moved horizontally into the carrier through the opening of the front side plate 14 and slowly lowered. When the fuel assembly 6 reaches its final position, the limiting plate 21 of the anti-tipping device 2 is triggered to swing out to the open position. The limiting plate 21 and the front side plate 14 work together to prevent the fuel assembly 6 from falling out of the front opening. After loading the fuel assembly 6 is complete, the lifting device 7 releases the fuel assembly 6 and moves away. In this embodiment, when the fuel assembly 6 descends to its position, the pull rod spring and the base spring are compressed, the base 28 is flattened and contacts the support block 27, and at the same time the base 28 drives the lower pull rod 25 to pull the upper pull rod 23 downward. The upper pull rod 23 drives the limiting plate 21 to swing out to the open position. The limiting plate 21 and the front side plate 14 work together to prevent the fuel assembly 6 from falling out of the front opening of the carrier. After the fuel assembly 6 is loaded, the lifting device 7 releases the fuel assembly 6 and resets to the initial state.

[0065] During material removal, the carrier is positioned vertically, the lifting device 7 grabs the fuel assembly 6 and slowly lifts it above the upper edge of the front side plate 14, while the limiting plate 21 of the anti-tipping device 2 returns to its retracted position; the fuel assembly 6 moves horizontally out of the front opening; the lifting device 7 quickly lifts the fuel assembly 6 away, and the material removal of the fuel assembly 6 is completed. In this embodiment, the base 28 is lifted by the action of the base spring, and the pull rod 25 is lifted at the same time. The pull rod spring returns to its original position, the limiting plate 21 retracts under the action of the pull rod spring, and after the fuel assembly 6 moves horizontally out of the front opening of the carrier, it is quickly lifted away by the lifting device 7.

[0066] This carrier structure solves the problem of low efficiency in loading and unloading fuel assembly 6. Fuel assembly 6 descends or rises from an open position on the outside of the carrier, with no objects around it that could cause it to scrape against the carrier. Therefore, fuel assembly 6 can descend and rise rapidly. Only after entering the carrier does the speed of fuel assembly 6 need to be controlled to avoid scraping against the sides of the carrier body 1; that is, only 3% to 5% of its total length requires a slow descent, thus greatly shortening the time for descent and retraction. Simultaneously, the fuel assembly 6 enters and exits the carrier using a translational method, resulting in short distances and less time spent, effectively improving the loading and unloading efficiency of fuel assembly 6.

[0067] Of course, there may be other embodiments of this utility model. Without departing from the spirit and essence of this utility model, those skilled in the art can make various corresponding changes and modifications based on this utility model, but these corresponding changes and modifications should all fall within the protection scope of the appended claims of this utility model.

Claims

1. A carrier, characterized in that The application relates to a fuel assembly transfer device. The device comprises a bearing body, guide wheels, a hinged shaft and an anti-toppling device. The bearing body comprises a left side plate, a right side plate, a back side plate, a front side plate and a bottom plate, wherein the left side plate, the right side plate, the back side plate and the front side plate are connected with the bottom plate and form a rectangular box with an open top and front, and the rectangular box is used for accommodating fuel assemblies to be transferred. The guide wheels are symmetrically installed at one end of the left side plate and the right side plate close to the top. The hinged shaft is symmetrically installed at one end of the left side plate and the right side plate close to the bottom, and the bearing body is installed on a transfer trolley through the hinged shaft and rotates around the axis of the hinged shaft to realize the conversion between the vertical position and the horizontal position. The anti-toppling device is installed on one side of the left side plate and / or the right side plate close to the front opening and at one end close to the top, and the anti-toppling device prevents the fuel assemblies to be transferred from falling out of the front opening together with the front side plate.

2. The carrier of claim 1, wherein The anti-toppling device comprises a limiting plate, a transmission mechanism and a control mechanism. The limiting plate is symmetrically installed on the left side plate and the right side plate through fixing blocks and has an opening position and a retracted position relative to the fixing blocks. The transmission mechanism comprises an upper pull rod, a lower pull rod and a pull rod reset piece, the two ends of the upper pull rod are connected with the limiting plate and the lower pull rod, and the pull rod reset piece is connected with the upper pull rod and the lower pull rod. The control mechanism is arranged on the bottom plate and connected with the transmission mechanism, and controls the limiting plate to switch between the opening position and the retracted position.

3. The carrier of claim 2, wherein, The control mechanism comprises a base, a supporting block and a base reset piece, the rear end of the base is hinged with the bottom plate, the supporting block is installed on the bottom plate corresponding to the front end of the base, the base reset piece is located between the base and the bottom plate, the lower end of the lower pull rod is connected with the base and drives the base to swing up and down with the base reset piece as the center, the base has a pressing position and a loosening position relative to the bottom plate, the limiting plate switches to the opening position when the base is located at the pressing position, and the limiting plate switches to the retracted position when the base is located at the loosening position.

4. The carrier of claim 3, wherein, The base reset piece is a base spring, the base spring is arranged at the middle position of the front part of the bottom plate and abuts against the base.

5. The carrier of claim 2, wherein, The distance from the limiting plate to the top end of the bearing body is 3%-4% of the height of the bearing body.

6. The carrier of claim 1, wherein A plurality of reinforcing ribs are arranged on the outer surfaces of the left side plate, the back side plate and the right side plate in parallel, and the reinforcing ribs prevent the expansion and deformation of the front opening of the bearing body.

7. The carrier of claim 6, wherein, The reinforcing rib is a U-shaped integral structure.

8. The carrier of claim 7, wherein, The distribution density of the reinforcing rib is matched with the deformation degree of the opening of the bearing body during the turnover of the bearing device, the interval of adjacent reinforcing ribs located on the upper part and the middle part of the bearing body is smaller than the interval of the reinforcing ribs located on the lower part of the bearing body.

9. The carrier of claim 1, wherein The top and the front opening of the bearing body are provided with guide bevel angles.

10. The carrier of claim 1, wherein The heights of the left side plate, the right side plate and the back side plate are equal, and the height of the front side plate is 3%-5% of the height of the back side plate.

Images