A nuclear fuel transport container and a nuclear fuel transport device thereof

Abstract

The nuclear fuel transport container provided by the present invention uses a plastically deformable and impact-resistant protective layer to wrap the tank body containing the nuclear fuel assembly, and a plurality of recessed holes for accommodating support columns are provided on the protective layer, so that the support columns can contact the tank body and bear the weight of the container, and the protective layer does not bear weight and uses an energy-absorbing structure to resist impact by plastic deformation, thereby improving the impact resistance.

Description

Technical Field

[0001] The invention belongs to the field of nuclear material loading equipment, and in particular relates to a nuclear fuel transport container. Background Art

[0002] New fuel assemblies are transported from the manufacturing plant to the nuclear power plant, and spent fuel assemblies are transported from the nuclear power plant to the processing plant or storage site in special containers. The container is a radiation-proof, neutron-proof, impact-resistant, and heat-dissipating / heat-insulating tank that can withstand transportation by train, ship, and car and multiple lifting. The cladding of the spent fuel assembly has become brittle and contains radioactive gas, so its transport container must have good impact resistance.

[0003] The buffer structure of the existing nuclear fuel transport container has to have a certain mechanical strength because it has to bear the weight of the contents and even the entire container, and cannot cope well with accidental tipping or falling during lifting. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to improve the impact resistance of a nuclear fuel transport container.

[0005] The present invention provides a nuclear fuel transport container, comprising a tank body for accommodating a nuclear fuel assembly and a protective layer wrapping the tank body, wherein the protective layer is plastically deformable to resist impact, and the protective layer is provided with a plurality of concave holes, wherein the concave holes are located on the bottom surface or the side surface of the tank body, and the concave holes are used to accommodate support columns, wherein the support columns are in contact with the tank body and bear the weight of the nuclear fuel transport container.

[0006] Optionally, the concave holes are divided into two groups, one group is located on the bottom surface of the can body, and the other group is located on the side surface of the can body.

[0007] With the above structure, the container can be placed in an upright position or in a horizontal position, thereby facilitating the transportation process and loading and unloading operations.

[0008] Optionally, the protective layer includes an outer shell and a plurality of buffer energy absorbing plates fixedly installed between the outer shell and the tank body, the concave hole is formed by the outer shell being partially concave and abutting against the surface of the tank body, the support column abuts against the tank body through the outer shell, and a ventilation path that bypasses or passes through the buffer energy absorbing plates is provided in the interlayer space between the outer shell and the tank body.

[0009] With the above structure, the container can alleviate the small impact of general vibration and vehicle acceleration through the elastic deformation of the buffer energy absorbing plate, and can absorb the severe impact of accidental collision or falling through plastic deformation.

[0010] Optionally, the shell is provided with two groups of ventilation holes, one group of which is close to the upper edge of the side of the tank body, and the other group of which is close to the lower edge of the side of the tank body.

[0011] With the above structure, the interlayer space between the shell and the tank body is provided with a ventilation path to facilitate air flow, and the gas in the interlayer space can be exchanged with the outside through two sets of ventilation holes, so that the protective layer also serves as a radiator, which is beneficial to the heat dissipation of the tank body. This is especially important for spent fuel assemblies.

[0012] Optionally, an elastic material layer is provided between the portion of the shell corresponding to the bottom surface of the recessed hole and the tank body, and the support column contacts the tank body through the shell and the elastic material layer in sequence.

[0013] Optionally, the elastic material layer is bonded and fixed wood, rubber or hard polyurethane foam.

[0014] Optionally, the buffer energy absorbing plate is a wavy or zigzag bent plate, the extending direction of the bent shape is perpendicular to the shell, and adjacent buffer energy absorbing plates are spaced apart and staggered with each other.

[0015] Optionally, the shell is provided with a plurality of slits, the buffer energy absorption plate is an alloy plate that can be plastically deformed at room temperature, one end of the buffer energy absorption plate is welded to the surface of the tank body, and the other end is welded in the slits one by one.

[0016] The present invention also provides a nuclear fuel transport container, which comprises the above-mentioned nuclear fuel transport container and a support base, wherein the support base comprises a plurality of support columns, and the support columns are inserted into the concave holes one by one and abut against the tank body.

[0017] Optionally, the support base is a frame structure, and the support columns are fixedly connected by a plurality of connecting rods.

[0018] The beneficial effects of implementing the present invention are mainly: a plastically deformable and impact-resistant protective layer is used to wrap the tank body containing the nuclear fuel assembly, and a plurality of recessed holes for accommodating support columns are provided on the protective layer, so that the support columns can contact the tank body and bear the weight of the container, and the protective layer does not bear weight and adopts an energy-absorbing structure to resist impact by plastic deformation, thereby improving impact resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following drawings should be used in conjunction with the detailed description.

[0020] Figure 1 is a cross-sectional schematic diagram of embodiment 1;

[0021] Figure 2 yes Figure 1 Schematic diagram of cross section at AA;

[0022] Figure 3 is a cross-sectional schematic diagram of the second embodiment in an upright state;

[0023] Figure 4 is a bottom view schematic diagram of the second embodiment in an upright state;

[0024] Figure 5a is a front view of the support frame in the second embodiment;

[0025] Figure 5b is a top view of the support frame in the second embodiment;

[0026] Figure 6 It is a cross-sectional schematic diagram of the third embodiment.

[0027] Figure 7 is a three-dimensional schematic diagram of the buffer energy absorption plate in the third embodiment;

[0028] The symbols in the accompanying drawings represent:

[0029] 1-tank body, 11-tank shell, 12-lead plate, 13-boron-rich stainless steel plate, 14-flange, 15-lifting ear, 16-bolt pair;

[0030] 2-protective layer, 201-concave hole, 202-ventilation hole, 21-shell, 22-buffer energy absorption plate, 221-panel, 222-connecting plate, 23-elastic material layer;

[0031] 3-support frame, 31-support column, 32-connecting rod. DETAILED DESCRIPTION

[0032] In order to fully understand the content of the present invention, embodiments are described below in conjunction with the accompanying drawings.

[0033] In this specification, orientation indicators such as "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the observation angles shown in the accompanying drawings; "circumferential" refers to a circle along which the center of the circle is the center of the cross-section; "format" refers to the visible surface of a component in the perspective direction with the largest projection area.

[0034] Embodiment 1

[0035] Nuclear fuel transport container. See Figure 1 and Figure 2 It comprises a tank body 1 for accommodating nuclear fuel assemblies and a protective layer 2 for wrapping the tank body. The tank body 1 is in the shape of a square column and is divided into two parts: a main body and a top cover. A pair of flanges 14 are provided at the joint between the main body and the top cover of the tank body 1. The flanges 14 are fixed by bolt pairs 16 and sealed by sealing rings. Two lifting ears 15 are provided on the top surface of the top cover of the tank body 1.

[0036] The protective layer 2 wraps the main body of the tank body 1, but exposes the top cover and flange 14 of the tank body 1. Because the container is used with the support base 3 described below, and the top cover is short in length and weighs much less than the container body, the top cover of the tank body 1 can be exposed.

[0037] The protective layer 2 includes an outer shell 21 and a plurality of buffering energy absorbing plates 22 fixedly installed between the outer shell 21 and the tank body 1. The protective layer 2 can resist impact by plastic deformation. Specifically, the outer shell 21 is made of a stainless steel sheet.

[0038] The protective layer is provided with 8 concave holes 201, of which 4 concave holes 201 are located on the bottom surface of the tank body 1, and the other 4 are located on the side surface of the tank body 1. The concave holes 201 are formed by partially concavely forming the outer shell 21. An elastic material layer 23 is provided between the portion of the outer shell 21 corresponding to the bottom surface of the concave holes 201 and the tank body 1. Specifically, the elastic material layer 23 is wood, rubber or hard polyurethane foam that is bonded and fixed.

[0039] See also Figure 3 The nuclear fuel transport container can be supported by a support frame 3, which is an independent frame. The support frame can also be a part of the load-bearing structure of a train, a ship, or a car.

[0040] The recessed hole 201 is used to accommodate the support column 31 of the support frame 3. The support column 31 contacts the tank body 1 through the outer shell 21 and the elastic material layer 23 in sequence. The support column 31 bears the weight of the nuclear fuel transport container, while the protective layer 2 does not bear the weight. The protective layer 2 undergoes elastic deformation and buffering under minor impacts during loading and unloading, acceleration, and deceleration, and undergoes plastic deformation and energy absorption under unexpected severe impacts, and can cope with traffic accidents or accidental tipping and falling during hoisting.

[0041] The buffering energy absorbing plate 22 is an iron alloy plate that can be plastically deformed at room temperature. The buffering energy absorbing plate 22 is a wavy bending plate, and the extension direction of its bending shape is perpendicular to the shell 21. The shell 21 is provided with a plurality of slits. One end of the buffering energy absorbing plate 22 is welded to the surface of the tank body 1, and the other end is welded in the above-mentioned slits one by one. Adjacent buffering energy absorbing plates 22 are spaced and staggered from each other, so as to form a ventilation path that passes through the buffering energy absorbing plate 22 in the interlayer space between the shell 21 and the tank body 1.

[0042] The housing 21 is provided with two groups of ventilation holes 202. One group of ventilation holes 202 is close to the upper edge of the side of the tank body 1, that is, close to the flange 14. The other group of ventilation holes 202 is close to the lower edge of the side of the tank body 1.

[0043] External air can enter the interlayer space between the outer shell 21 and the tank body 1 from the ventilation holes 202 at the lower side of the tank body 1, pass through the ventilation path between the buffer energy absorption plate 22, and be discharged from the ventilation holes 202 at the upper side of the tank body 1. The buffer energy absorption plate 22 also has the function of passive heat dissipation. Because the spent fuel will continue to dissipate heat, its transport container must have a certain heat dissipation capacity.

[0044] The tank shell 11 of the tank body 1 is a stainless steel component. The tank shell 11 is lined with a lead plate 12. The internal space of the tank body 1 is divided into four square columnar compartments by a boron-rich stainless steel plate 13. Each compartment is used to place a nuclear fuel assembly. The main function of the lead plate 12 is to shield high-energy rays. The boron-rich stainless steel plate 13 can absorb neutrons to prevent the spent fuel assembly from reaching a critical state.

[0045] In other embodiments, the tank body 1 may be cylindrical or other polygonal shapes, and may be hinged on the side and fixed by snaps, but the contact surface with the support column should be arranged horizontally.

[0046] In other embodiments, the number of the lifting lugs may be 3 or 4, or more and may be divided into two, three or four groups, thereby preventing accidents caused by damage to the lifting structure.

[0047] In other embodiments, the top cover of the tank body 1 may be wrapped with a protective layer 2 or other buffer layer.

[0048] In other embodiments, there may be only one group of concave holes 201 disposed on the side or bottom of the tank body 1 , and the number of the concave holes 201 may be 3, 5, 6 or 8.

[0049] In other embodiments, the shell 21 portion of the bottom surface of the recessed hole 201 may directly contact the tank body 1 , or the recessed hole 201 may be a through hole. However, an elastic material layer 23 is provided on the top surface of the support column 31 .

[0050] In other embodiments, both ends of the buffer energy absorbing plate 22 are fixedly installed in the interlayer space between the outer shell 21 and the tank body 1 by bolts.

[0051] In other embodiments, the internal space of the tank body 1 may be divided into two or three compartments, or may not be divided, depending on the size, structure and weight of the specific fuel assembly. The overall weight of the container should generally be controlled to take into account both efficiency and safety of transportation.

[0052] Embodiment 2

[0053] Nuclear fuel transport unit, see Figures 3 to 5bIt includes the nuclear fuel transport container of the first embodiment and a frame-type support base 3. The support base 3 includes four support columns 31, which are inserted into four recessed holes 201 at the bottom of the tank body 1 one by one and abut against the tank body 1. The support columns 31 are fixedly connected by a plurality of connecting rods 32.

[0054] In other embodiments, the support seat 3 matches with the four recessed holes 201 on the side of the tank body 1 .

[0055] In other embodiments, the number of the support pillars 31 is 3, 5, 6 or 8, corresponding to the number of a group of recessed holes 201. An elastic material layer 23 is disposed on the top of the support pillars 31.

[0056] Embodiment 3

[0057] The nuclear fuel transport container is an improvement on the first embodiment. Figure 6 and Figure 7 The main improvements are:

[0058] The buffer energy absorption plate 22 is an aluminum alloy plate that can be plastically deformed at room temperature. The buffer energy absorption plate 22 is in the shape of a long strip, and is composed of two panels 221 and three connecting plates 222. The connecting plates 222 are perpendicular to and located between the two panels 221, and the connecting plates 222 extend in the length direction of the buffer energy absorption plate 22. The two outer surfaces of the buffer energy absorption plate 22 are respectively fixed to the tank body 1 and the outer shell 21 by adhesive or bolts. Air circulation is allowed between the two ends of the buffer energy absorption plate 22. External air can enter the interlayer space between the outer shell 21 and the tank body 1 from the ventilation hole 202 at the lower side of the tank body 1, and pass through the ventilation path between and inside the buffer energy absorption plate 22, and be discharged from the ventilation hole 202 near the upper side of the tank body 1.

[0059] The nuclear fuel transport container is basically the same as that of the first embodiment in other aspects.

[0060] The typical embodiments described above embody the technical concept and features of the present invention, so that those skilled in the art can understand the content of the invention and implement it accordingly, but do not constitute any limitation on the protection scope of the present invention. Simple changes or equivalent transformations to the above embodiments are still within the protection scope of the present invention.

Claims

1. A nuclear fuel transport container, comprising a tank body for accommodating a nuclear fuel assembly and a protective layer wrapping the tank body, It is characterized in that The protective layer is plastically deformable to resist impact, and is provided with a plurality of concave holes, wherein the concave holes are used to accommodate support columns, and the support columns are in contact with the tank body and bear the weight of the nuclear fuel transport container; The concave holes are divided into two groups, one of which is located on the bottom surface of the can body, and the other is located on the side surface of the can body.

2. The nuclear fuel transport container according to claim 1, It is characterized in that The protective layer includes an outer shell and a plurality of buffer energy absorbing plates fixedly installed between the outer shell and the tank body. The concave hole is formed by the outer shell being partially concave and abutting against the surface of the tank body. The support column abuts against the tank body through the outer shell. A ventilation path that passes through or passes through the buffer energy absorbing plates is provided in the interlayer space between the outer shell and the tank body.

3. The nuclear fuel transport container according to claim 2, It is characterized in that The shell is provided with two groups of ventilation holes, one group of which is close to the upper edge of the side of the tank body, and the other group of which is close to the lower edge of the side of the tank body.

4. The nuclear fuel transport container according to claim 2, It is characterized in that An elastic material layer is provided between the portion of the shell corresponding to the bottom surface of the concave hole and the tank body, and the support column contacts the tank body through the shell and the elastic material layer in sequence.

5. The nuclear fuel transport container according to claim 4, It is characterized in that The elastic material layer is bonded and fixed wood, rubber or hard polyurethane foam.

6. The nuclear fuel transport container according to claim 2, It is characterized in that The buffer energy absorption plate is a wave-shaped or sawtooth-shaped bent plate, the extending direction of the bent shape is perpendicular to the shell, and the adjacent buffer energy absorption plates are spaced apart and staggered with each other.

7. The nuclear fuel transport container according to claim 6, It is characterized in that The shell is provided with a plurality of slits, the buffer energy absorption plate is an alloy plate which can be plastically deformed at room temperature, one end of the buffer energy absorption plate is welded to the surface of the tank body, and the other end is welded in the slits in a one-to-one correspondence.

8. A nuclear fuel transport device, It is characterized in that It comprises the nuclear fuel transport container and the support seat as described in any one of claims 1 to 7, wherein the support seat comprises a plurality of support columns, and the support columns are inserted into the recessed holes one by one and abut against the tank body.

9. The nuclear fuel transport device according to claim 8, It is characterized in that The support seat is a frame structure, and the support columns are fixedly connected by a plurality of connecting rods.

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