Apparatus for transporting nuclear fuel assembly within nuclear power plant comprising small modular reactors (SMRS), and transport method using same

Abstract

The present invention relates to an apparatus for transporting a nuclear fuel assembly, the apparatus, which transports a nuclear fuel assembly within a nuclear power plant comprising small modular reactors (SMRs), comprising: a hoist box that can move within the nuclear power plant, moving between the SMRs and nuclear fuel assembly; a fixing part partially attached to the nuclear fuel assembly to fix same; first and second wires connecting the hoist box and fixing part, the first wire supporting the fixing part during the lowering stage; and a stiffness adjustment part for adjusting the stiffness of the second wire.

Description

A transport device for nuclear fuel assemblies in a nuclear power plant including a small modular reactor (SMR) and a transport method using the same

[0001] The present invention relates to a transport device for a nuclear fuel assembly in a nuclear power plant including a small modular reactor (SMR) and a transport method using the same.

[0002] For the reloading and transport of existing nuclear fuel, a refueling machine (Refueling Machine) was used, consisting of a movable bridge and a trolley. The bridge within the refueling machine operates on rails installed within the reactor, and the trolley is equipped with a multi-stage, rigid hoist box used for reloading and transporting nuclear fuel assemblies.

[0003] However, the existing transport device has problems such as the limitation of the maximum length design of the multi-stage hoist box, the problem of the upper head of the reactor and the trolley coming into contact when the bridge operating floor position is lowered, the problem of movement due to the increase in weight according to the increase in the length and volume of the hoist box, and the difficulty of precision adjustment due to the complex configuration of the transport device.

[0004] The purpose of the present invention is to provide a transport device for a nuclear fuel assembly in a nuclear power plant including a small modular reactor (SMR) and a transport method using the same.

[0005] The present invention relates to a nuclear fuel assembly transport device in a nuclear power plant including a small modular reactor (SMR), comprising: a hoist box that moves between the small modular reactor and the nuclear fuel assembly and is movable within the nuclear power plant; a fixing member that is fixed by being at least partially connected to the nuclear fuel assembly; a first wire and a second wire that connect the hoist box and the fixing member, wherein the first wire supports the fixing member during a lowering process; and a stiffness adjusting member that adjusts the stiffness of the second wire.

[0006] The above second wire is provided in multiple numbers around the first wire and may be made of a shape memory alloy (SMA).

[0007] The above stiffness control unit can control the stiffness of the second wire by supplying current to the second wire.

[0008] The above second wire may have its rigidity increased when current is supplied by the rigidity control unit, and its rigidity may decrease when the current supply is released.

[0009] It further includes a distance measuring unit for measuring the distance between the nuclear fuel assembly and the fixing unit, and the distance measuring unit may include a camera.

[0010] The present invention relates to a method for transporting a nuclear fuel assembly in a nuclear power plant including a small modular reactor (SMR), comprising: a step of positioning a hoist box above the nuclear fuel assembly; a step of lowering a fixing part connected to the hoist box via a first wire and a second wire from the hoist box; a step of increasing the rigidity of the second wire to restrict movement between the first wire and the fixing part, thereby bringing the fixing part closer to the nuclear fuel assembly; a step of connecting the nuclear fuel assembly to the fixing part and releasing the increase in rigidity of the second wire; and a step of moving the nuclear fuel assembly upward.

[0011] The lowering of the above fixed part is performed by a first wire that is connected to the hoist box and the fixed part and supports the fixed part, and at this time, the second wire may be flexible.

[0012] The increase in the rigidity of the second wire is performed by supplying current to the second wire, and the second wire can be changed into a rigid state by the current supply.

[0013] It further includes a step of measuring the distance between the nuclear fuel assembly and the fixing member, and the lowering of the fixing member can be performed based on the measured distance.

[0014] According to the present invention, a transport device for a nuclear fuel assembly in a nuclear power plant including a small modular reactor (SMR) and a transport method using the same are provided.

[0015] FIG. 1 is a plan view of a nuclear power plant including a small modular reactor (SMR) including a nuclear fuel assembly transport device according to one embodiment of the present invention.

[0016] Figure 2 illustrates a nuclear fuel assembly transport device according to one embodiment of the present invention.

[0017] Figure 3 is a plan view of a hoist box of a nuclear fuel assembly transport device according to one embodiment of the present invention.

[0018] Figure 4 is a flowchart showing a method for transporting a nuclear fuel assembly according to an embodiment of the present invention.

[0019] FIGS. 5a and 5b illustrate the operation of a transport device in a method for transporting a nuclear fuel assembly according to one embodiment of the present invention.

[0020] The present invention will be described in more detail with reference to the drawings below.

[0021] The attached drawings are merely examples intended to more specifically illustrate the technical concepts of the present invention, and therefore, the scope of the present invention is not limited to the attached drawings. Furthermore, the attached drawings may exaggerate the size and spacing of components to illustrate the relationships between components.

[0022] Hereinafter, the “small modular reactor” or “integrated reactor” in the present invention is also called a small modular reactor, and refers to a reactor in which a steam generator and a pressurizer are arranged within the reactor.

[0023] FIG. 1 is a plan view of a nuclear power plant including a small modular reactor (SMR) including a nuclear fuel assembly transport device according to one embodiment of the present invention.

[0024] The nuclear power plant (P) of the present invention includes a small modular reactor (10), a nuclear fuel assembly (20), a central space (30), a cooling water tank (40), a bulkhead (50), and a crane (60).

[0025] Referring to FIG. 1, the central space (30) may be the same as or include a maintenance space (S) for maintenance of a small modular reactor (10).

[0026] In the present invention, the shape of the central space (30) is illustrated as a ring, but is not limited thereto and may be modified into various shapes such as an oval or a polygon. In the present invention, the shape refers to a cross-section in a horizontal direction.

[0027] The cooling water tank (40) surrounds the central space (30), and a small modular reactor (10) and a nuclear fuel assembly (20) are positioned inside, and the cooling water is filled so that the small modular reactor (10) and the nuclear fuel assembly (20) can be sufficiently submerged.

[0028] Although not shown, an additional cooling water supplement device may be installed to prevent cooling water from being lost in the cooling water tank (40) in the event of an accident in the small modular reactor (10).

[0029] Additionally, additional support structures may be installed to secure and support the small modular reactor (10) and nuclear fuel assembly (20) located within the cooling water tank (40).

[0030] A plurality of bulkheads (50) are installed to spatially separate the small modular reactors (10) and nuclear fuel assemblies (20) arranged at regular intervals inside the cooling water tank (40).

[0031] Referring to FIG. 1, in the present invention, the bulkhead (50) is illustrated as being installed near the nuclear fuel assembly (20), but is not limited thereto.

[0032] The bulkhead (50) separates the small modular reactor (10) and the nuclear fuel assembly (20) and can be opened and closed. The flow of coolant within the cooling water tank (40) is achieved by changing the position of the bulkhead (50).

[0033] The coolant level in the individual space where the small modular reactor (10) and nuclear fuel assembly (20) are located is maintained constant by opening and closing the bulkhead (50).

[0034] The bulkhead (50) may be formed as a sluice gate or door that can be opened and closed, but is not limited thereto.

[0035] The crane (60) can move the small modular reactor (10) and nuclear fuel assembly (20) to the cooling water tank (40) and the central space (30).

[0036] The crane (60) may be installed inside or outside the nuclear power plant (P) and can move the small modular reactor (10) to the maintenance space (S) for maintenance.

[0037] Referring to FIGS. 2 and 3, a device for transporting a nuclear fuel assembly in a nuclear power plant including a small modular reactor (SMR) according to one embodiment of the present invention is described.

[0038] FIG. 2 illustrates a nuclear fuel assembly transport device according to an embodiment of the present invention, and FIG. 3 illustrates a plan view of a hoist box of a nuclear fuel assembly transport device according to an embodiment of the present invention.

[0039] In the present invention, the nuclear fuel assembly transfer device (T) includes a hoist box (100), a fixing part (200), a first wire (300), a second wire (400), a rigidity adjusting part (500), and a distance measuring part (600).

[0040] The hoist box (100) moves between the small modular reactor (10) and the nuclear fuel assembly storage tank (20), and can be moved inside the nuclear power plant (P).

[0041] Although not shown, the hoist box (100) is coupled to at least a portion of a crane (60) installed inside a nuclear power plant (P), and is capable of moving along a guide rail of the crane (60), and may further include a separate roller and a driving motor for driving the roller to enable free horizontal movement along the guide rail.

[0042] The fixed part (200) is fixed by being joined to at least a portion of the nuclear fuel assembly (20).

[0043] In the present invention, the fixing member (200) is in the form of a clamp for fixing the nuclear fuel assembly (20), but is not limited thereto.

[0044] Although not shown, the fixed part (200) may further include a plurality of fixed blades. The plurality of fixed blades can be tilted by a power source not shown, and the nuclear fuel assembly (20) can be fixed (gripped) by tilting the fixed blades.

[0045] The first wire (300) connects the hoist box (100) and the fixed part (200), and is made of wire or steel, etc., which can be adjusted in length and wound. In the present invention, the first wire (300) may be formed by a plurality of wires being bundled together or twisted, but is not limited thereto.

[0046] Although not shown, a separate winding tool for winding the first wire (300) may be further installed in the hoist box (100). The winding tool includes a pulley and a drum.

[0047] The second wire (400) connects the hoist box (100) and the fixed part (200).

[0048] Referring to FIGS. 2 and 3, in the present invention, a plurality of second wires (400) are provided around the first wire (300), but this is not limited thereto.

[0049] In the present invention, the second wire (400) may be made of a shape memory alloy (SMA). The second wire (400) has an adjustable length and can be wound.

[0050] Although not shown, a separate winding tool for winding the second wire (400) may be further installed in the hoist box (100). The winding tool includes a pulley and a drum.

[0051] The stiffness control unit (500) controls the stiffness of the second wire (400) by supplying current to the second wire (400). The stiffness control unit (500) includes, but is not limited to, a current application device capable of applying current to the second wire (400).

[0052] In the present invention, the stiffness adjustment unit (500) may be installed inside or outside the hoist box (100), but is not limited thereto. The installation location of the stiffness adjustment unit (500) may vary depending on the installation location of the second wire (400).

[0053] In the present invention, the distance measuring unit (600) measures the distance between the nuclear fuel assembly (20) and the fixing unit (200), and includes a camera. The distance measuring unit (600) used in the present invention must be capable of long-term use in the working environment of a nuclear power plant, such as an underwater environment and a high-radiation environment, and may be structured to allow easy replacement by workers.

[0054] In another embodiment, the distance measuring unit (600) uses multiple sensors. Here, the multiple sensors may be ultrasonic sensors.

[0055] Referring to FIGS. 4, 5a and 5b, a method for transporting a nuclear fuel assembly using a nuclear fuel assembly transport device according to an embodiment of the present invention will be described.

[0056] FIG. 4 is a flowchart showing a method for transporting a nuclear fuel assembly according to an embodiment of the present invention, and FIGS. 5a and 5b show the operation of a transport device in a method for transporting a nuclear fuel assembly according to an embodiment of the present invention.

[0057] First, the hoist box is positioned on top of the nuclear fuel assembly. (S100)

[0058] The hoist box moves horizontally to the top of the nuclear fuel assembly that needs to be transported via the crane's guide rail.

[0059] In the present invention, the movement of the hoist box may be performed according to the coordinate values ​​of the nuclear fuel assembly that have been previously set, but is not limited thereto.

[0060] Thereafter, referring to Fig. 5a, the fixed part connected to the hoist box via the first wire and the second wire is lowered from the hoist box. (S200)

[0061] At this time, the lowering of the fixed part is performed by the first wire that is connected to the hoist box and the fixed part and supports the fixed part. At this time, the second wire is in a flexible state.

[0062] Next, the stiffness of the second wire is increased to bring the fixed part closer to the nuclear fuel assembly while limiting the movement between the first wire and the fixed part. (S300)

[0063] Here, the stiffness of the second wire is increased by supplying current to the second wire, and the second wire is changed to a rigid state by the current supply, thereby fixing the movement of the fixed part.

[0064] Thereafter, the fixed part, whose movement is fixed according to the change in the state of the second wire, descends toward the nuclear fuel assembly based on the measured distance between the nuclear fuel assembly and the fixed part. (S400)

[0065] In the present invention, the distance between the nuclear fuel assembly and the fixing member is first measured using a camera, and when the distance value measured using the camera falls within a specific range, the fixing member is lowered.

[0066] Referring to Figure 5b, the nuclear fuel assembly is connected to the fixing member, and the stiffness increase of the second wire is released. (S500)

[0067] At this time, the second wire changes to a flexible state again as the stiffness enhancement is released, and as a result of this change in the state of the second wire, the fixed part connected to the nuclear fuel assembly is no longer restricted in its movement.

[0068] Finally, the nuclear fuel assembly connected to the fixed part is moved upward. (S600)

[0069] The present invention allows access to the nuclear fuel assembly transfer device within the crane's travel radius, thereby enabling efficient transfer and reloading of nuclear fuel assemblies within a nuclear fuel assembly storage tank containing multiple reactor modules. Furthermore, compared to existing transfer devices in which the hoist box is lowered from the crane, the design is simplified and installation is possible, thereby reducing construction costs.

[0070] The embodiments of the present invention described above and illustrated in the drawings should not be construed as limiting the technical concept of the present invention. The scope of protection of the present invention is limited only by the matters set forth in the claims, and those skilled in the art will be able to make various improvements and modifications to the technical concept of the present invention. Accordingly, such improvements and modifications, as long as they are obvious to those skilled in the art, will fall within the scope of protection of the present invention.

Claims

1. In a nuclear fuel assembly transport device in a nuclear power plant including a small modular reactor (SMR), A hoist box that moves between the small modular reactor and the nuclear fuel assembly and can be moved within the nuclear power plant; A fixing member that is fixed by being joined to at least a portion of the nuclear fuel assembly; A first wire and a second wire connecting the hoist box and the fixed part, wherein the first wire supports the fixed part during the lowering process; and A nuclear fuel assembly transfer device including a stiffness control unit for controlling the stiffness of the second wire.

2. In paragraph 1, The above second wire is provided in multiple numbers around the above first wire, and is a transport device for a nuclear fuel assembly made of a shape memory alloy (SMA).

3. In paragraph 1, The above rigidity control unit, A nuclear fuel assembly transfer device that controls the stiffness of the second wire by supplying current to the second wire.

4. In paragraph 3, The above second wire, A nuclear fuel assembly transport device whose rigidity increases when current is supplied by the above-mentioned rigidity control unit, and whose rigidity decreases when the current supply is released.

5. In paragraph 1, Further comprising a distance measuring unit for measuring the distance between the nuclear fuel assembly and the fixing unit, The above distance measuring unit is a transport device for a nuclear fuel assembly including a camera.

6. Regarding a method for transporting nuclear fuel assemblies in a nuclear power plant including a small modular reactor (SMR), A step of positioning a hoist box on top of the nuclear fuel assembly; A step of lowering a fixed member connected to the hoist box through the first wire and the second wire from the hoist box; A step of increasing the rigidity of the second wire and bringing the fixing member closer to the nuclear fuel assembly while restricting movement between the first wire and the fixing member; A step of connecting the nuclear fuel assembly to the fixing member and releasing the increase in rigidity of the second wire; and A method for transporting a nuclear fuel assembly, comprising: a step of moving the nuclear fuel assembly upward; 7. In paragraph 5, The lowering of the above fixed part is A method for transporting a nuclear fuel assembly, the method comprising: connecting the hoist box and the fixed member to the first wire supporting the fixed member; wherein the second wire is flexible.

8. In paragraph 6, The increase in the stiffness of the above second wire is It is performed by supplying current to the second wire above, A method for transporting a nuclear fuel assembly in which the second wire is changed into a rigid state by the above current supply.

9. In paragraph 6, Further comprising a step of measuring the distance between the nuclear fuel assembly and the fixing member, A method for transporting a nuclear fuel assembly, wherein the lowering of the above-mentioned fixed part is performed based on the measured distance.

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