Designed storage device with reduced costs for storing and / or transporting nuclear fuel assemblies

Abstract

The present invention relates to a storage device (1) for storing and / or transporting nuclear fuel assemblies, comprising N adjacent recesses (4), some of which are made by intersecting and stacked plates (14a, 14b) with cutouts, in at least one cross-section, at least one of the adjacent recesses (4) has an inner surface defining a recess (10), the inner surface being formed in part by a first surface (14a') of a plate (14a) with a first cutout made with boron and a first surface (14b') of a plate (14b) with a second cutout made without boron.

Description

[Technical field]

[0001] The present invention relates to the field of the transport and / or storage of nuclear fuel assemblies, preferably spent assemblies in which the fuel has been irradiated. [Background technology]

[0002] Such devices, also known as storage "baskets" or storage "racks," include a number of adjacent housings each capable of receiving a nuclear fuel assembly.

[0003] This storage device, intended to be housed within the cavity of a container, is designed to be able to simultaneously perform three basic functions, which will now be briefly described.

[0004] Firstly, it consists in the function of thermally transferring the heat given off by the fuel assemblies. Typically, aluminium or one of its alloys is used because of its good thermal conductivity.

[0005] The second function concerns neutron absorption and the problem of keeping the storage device subcritical when it is loaded with fuel assemblies. This is accomplished using neutron absorbing materials such as boron.

[0006] Finally, the third basic function concerns the mechanical strength of the device. It should be noted that the overall mechanical strength of the device must comply with the regulatory safety requirements for the transport / storage of nuclear material, especially with regard to the so-called "free fall" test.

[0007] From the prior art it is known to form a basket by superimposing stages made using structural assemblies with stacked and interlocked cutouts, these assemblies further made using the same aluminum-based material with a certain boron concentration to perform the neutron absorption function and to achieve the required effective multiplication factor "keff".

[0008] However, embodiments of such structural assemblies having boron-containing cutouts have proven to be particularly costly, significantly impacting the overall manufacturing costs of the storage device. Summary of the Invention [Problem to be solved by the invention]

[0009] It is therefore an object of the present invention to remedy the above-mentioned drawbacks associated with prior art embodiments. [Means for solving the problem]

[0010] To this end, the invention relates to a storage device for transporting and / or storing nuclear fuel assemblies, the storage device being intended to be housed in a cavity of a container for transporting and / or storing the nuclear fuel assemblies and comprising N adjacent housings, each intended to receive a nuclear fuel assembly, at least some of the N adjacent housings being made using flat bars with cutouts, interlocked and stacked in a stacking direction that is parallel to a central longitudinal axis of the storage device.

[0011] According to the invention, in at least one cross-section of the storage device passing through N adjacent housings, at least one of the adjacent housings, and preferably each of a plurality of the N adjacent housings, has an inner housing-defining surface, the inner housing-defining surface being: a first surface of a first flat bar having a notch made with boron, the second surface of the first flat bar on the opposite side of the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; a first surface of a second flat bar having a cutout made without using boron, the second surface of the second flat bar opposite the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; It is formed in part by

[0012] The originality of the invention therefore consists in the heterogeneity of these flat bars forming a single housing intended to receive a nuclear fuel assembly, in particular by providing at least one second flat bar with a cutout made without boron. This principle is derived from an unexpected observation. In fact, it has been found that the manufacturing costs are significantly reduced when a housing is made with non-borated flat bars and other flat bars with a certain boron content, compared to the conventional solutions resulting in the same effective multiplication factor, where all flat bars contain boron at a content below said certain boron content. In other words, the invention makes it possible to associate non-borated flat bars with borated flat bars with a boron content that exceeds the homogeneous content provided in the solutions of the prior art with equivalent performance.

[0013] Advantageously, this principle helps to reduce the cost of fabricating a storage device while still providing a storage device with high performance in terms of criticality.

[0014] The invention also provides at least any one of the following optional features, either alone or in combination:

[0015] Preferably, each of the plurality of cross sections of the storage device passing through each of the N adjacent housings and at least one of the adjacent housings, preferably each of a plurality of the N adjacent housings, has an inner housing-defining surface, the inner housing-defining surface being: a first surface of a first flat bar having a notch made with boron, the second surface of the first flat bar on the opposite side of the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; a first surface of a second flat bar having a cutout made without using boron, the second surface of the second flat bar opposite the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; It is formed in part by

[0016] More preferably, this feature is observed in all cross-sections of the storage device or in substantially all of these planes.

[0017] Preferably, the N adjacent housings are divided into a peripheral housing and an inner housing, and within one cross-section of the storage device through the N adjacent housings, or within each of a plurality of cross-sections of the storage device through each of the N adjacent housings, at least 50% of the peripheral housings each have an inner housing-defining surface that is a first surface of a first flat bar having a notch made with boron, the second surface of the first flat bar on the opposite side of the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; a first surface of a second flat bar having a cutout made without using boron, the second surface of the second flat bar opposite the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; It is formed in part by

[0018] Preferably, within one cross-section of the storage device through N adjacent housings, or within each of a plurality of cross-sections of the storage device through each of the N adjacent housings, at least 50% of the N adjacent housings each have an inner housing-defining surface, the inner housing-defining surface being: a first surface of a first flat bar having a notch made with boron, the second surface of the first flat bar on the opposite side of the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; a first surface of a second flat bar having a cutout made without using boron, the second surface of the second flat bar opposite the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; It is formed in part by

[0019] Preferably, within one cross-section of the storage device through N adjacent housings, or within each of a plurality of cross-sections of the storage device through each of the N adjacent housings, at least one of the adjacent housings, and preferably each of a plurality of the N adjacent housings, has an inner housing-defining surface having a generally square or rectangular cross-section, the inner housing-defining surface being a first surface of a first flat bar having a notch made with boron, the second surface of the first flat bar on the opposite side of the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; a first surface of a second flat bar having a cutout made without boron, the second surface of the second flat bar opposite the first surface contributing to the formation of an inner housing-defining surface of at least one other of the N adjacent housings; Two other flat bars with notches It is formed by:

[0020] Additionally, the first flat bar, the second flat bar, and the two other flat bars each form four sides of an inner housing-defining surface having a generally square or rectangular cross-section.

[0021] Preferably, the two other flat bars with cutouts are two first flat bars having notches made of boron; two second flat bars with notches made without boron, or A first flat bar having a notch made with boron and a second flat bar having a notch made without boron are formed by

[0022] Preferably, the flat bars with cutouts stacked and interlocked inside the storage device are either a first flat bar with cutouts made with boron, preferably at the same boron content, or a second flat bar with cutouts made without boron.

[0023] Preferably, the at least one first flat bar having a cutout is made in a single piece from an aluminium alloy, preferably comprising boron, and / or the at least one first flat bar having a cutout comprises a coating, preferably comprising boron, applied onto an aluminium alloy material.

[0024] Preferably, the at least one second flat bar with the notch is made from a boron-free aluminum alloy.

[0025] Preferably, the stacked and interlocked flat bars together form partitions defining adjacent housings, each partition extending along or substantially along the entire height of the storage device, each partition comprising: A stack of first flat bars having a notch A second flat bar having a notch is stacked on top of the second flat bar. by alternating first and second flat bars having cutouts, or The first and second flat bars are arranged alternately, the first and second flat bars having a notch, and a structural element, preferably made of steel, is further arranged between the first and second flat bars. is formed.

[0026] In this regard, it is possible to provide first flat bars with cutouts each having a different boron content within the same partition, even if it is preferred that the total boron content of the first flat bars remains constant within the same partition, and even more preferably, the total boron content of these first flat bars remains constant throughout the storage device.

[0027] The invention also relates to a vessel for storing and / or transporting nuclear fuel assemblies, said vessel comprising a cavity in which the above-mentioned storage device is housed.

[0028] The invention also relates to a shipment comprising such a container and nuclear fuel assemblies arranged in adjacent housings of a storage device of said container.

[0029] Further advantages and features of the present invention will become apparent in the following non-limiting detailed description.

[0030] This description makes reference to the accompanying drawings. [Brief description of the drawings]

[0031] [Figure 1] 1 is a schematic cross-sectional view of a transport according to the invention, comprising in particular a storage device for storing and / or transporting nuclear fuel assemblies; [Diagram 2]FIG. 1 is a partial perspective view of a storage device according to a first preferred embodiment of the present invention. [Diagram 3] FIG. 3 is a partial cross-sectional view taken along cross-section P in FIG. 2. [Figure 4] FIG. 4 is a perspective view of a portion of the storage device shown in FIGS. 2 and 3. [Diagram 5] FIG. 4 is a partially enlarged view of the partial cross-sectional view shown in FIG. [Figure 6] FIG. 3 is a partial perspective view similar to that of FIG. 2, but on an enlarged scale, in which a storage device in the form of a second preferred embodiment of the invention is presented. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] 1, a transport 100 is shown comprising a container 200 for storing and / or transporting irradiated nuclear fuel assemblies 2. The container 200 has a body 202 formed by a side body 204, a bottom 206, and a removable lid 208. The bottom 206 and the lid 208 are spaced apart from one another along a central longitudinal axis 3 of the container, about which the side body 204 extends.

[0033] The container 200 defines a cavity 210 within its body, in which the storage device 1, hereafter referred to as the "basket", is housed. As will be described in more detail hereafter, the basket 1 comprises a number of adjacent housings, each intended to receive one of the nuclear fuel assemblies 2. When the basket 1 is housed within the cavity 210 of the container 200 and the nuclear fuel assemblies 2 are placed within the adjacent housings of the basket 1, the transport 100 is said to be "loaded".

[0034] For reference, it is noted that the container may have shock absorbing covers 212 at the axial ends of the container, which respectively cover the lid 208 and bottom 206 of the body 202 of the container.

[0035] The particularity of the invention lies in the design of a basket 1 for transporting and / or storing irradiated nuclear fuel assemblies, which will now be described first with reference to FIGS.

[0036] As shown in Figures 2 and 3, the basket 1 comprises a number of adjacent housings 4, 4' arranged parallel to an axis 3, which further corresponds to the central longitudinal axis of the basket.

[0037] In this case the number N of adjacent housings is 69, but it will be apparent that this number can be different, for example anywhere between 10 and 100.

[0038] Each of the housings 4, 4' is capable of receiving at least one fuel assembly 2 having a square cross-section, and preferably only one fuel assembly 2. The housings 4, 4' thus have an inner housing-defining surface 10 having a cross-section of generally square or rectangular shape. The term "inner housing-defining surface 10" refers to the surface of the basket element that is disposed directly facing the outer surface of the fuel assembly 2 (two fuel assemblies 2 are shown in FIG. 3).

[0039] Thus, the housings 4, 4' are provided juxtaposed to each other. The housings 4, 4' are made of a plurality of mutually parallel first dividing partitions 9 and a plurality of mutually parallel second dividing partitions 11 perpendicular to the first partitions 9.

[0040] The first partitions 9 and the second partitions 11 are both parallel to the axis 3. In the embodiment shown in Figures 2 and 3, eight first partitions 9 and eight second partitions 11 are provided. These partitions 9, 11 are completed by four peripheral partitions 13 and four tubes 15 each forming a peripheral housing 4'. In this respect, it is pointed out that the N adjacent housings are divided into N1 peripheral housings 4' and N2 inner housings 4. Here, the N adjacent housings consist of 24 peripheral housings 4' and 45 inner housings 4. The term "peripheral housings" denotes the housings that define a closed peripheral row of housings 4' that is intersected by an imaginary peripheral line of the basket 1 and that surrounds the inner housings 4. The N1 peripheral housings 4' are thus divided here into four peripheral segments of five housings 4' and four housings 4' each defined by one of the tubes 15 arranged between the ends of the peripheral segments.

[0041] The first dividing partition 9 and the second dividing partition 11 are made using flat bars 14a, 14b stacked and interlocked along the axis 3. More specifically, this stacking of these flat bars with cutouts makes it possible to define all of the N2 inner housings 4 and also partially contributes to the definition of the peripheral housing 4', except for the peripheral housing 4' defined by the tube 15.

[0042] 4, which shows only some of the flat bars 14a, 14b of the basket 1, each of these flat bars 14a, 14b has a notch 16 at its bottom and top edge. In this case, these notches 16 of the flat bars 14a, 14b cooperate in pairs to form a so-called "matrix" structure, in which the flat bars 14a, 14b are stacked and interlocked in orthogonal directions.

[0043] In this first preferred embodiment, each partition 9, 11 obtained by stacking and interlocking the flat bars 14a, 14b is preferably formed by a series of a plurality of first flat bars 14a or by a series of a plurality of second flat bars 14b. In this case, each partition thus formed extends along the entire height of the basket 1, which is substantially parallel to the axis 3 along this entire height. In the transverse direction, each dividing partition 9, 11 also extends locally along the entire width of the basket 1, which also applies with respect to each flat bar 14a, 14b forming said partition. The first flat bars 14a and the second flat bars 14b are thus stacked along a stacking direction 20 parallel to the axis 3 and corresponding to the height direction of the basket 1. Preferably, all the first flat bars 14a are made of a single material, as are all the second flat bars 14b made of a single material different from the first flat bars.

[0044] In the case of the first flat bars 14a, these bars 14a contain boron. Preferably, the first flat bars 14a are made from a single piece of aluminum alloy containing boron. In this case, the boron can be homogeneously or heterogeneously distributed in the flat bars 14a. The boron content in this alloy is adapted according to several criteria, such as the effective multiplication factor "Keff" required, the ratio between the number of the first flat bars 14a and the number of the second flat bars 14b, the position of the first flat bars 14a inside the basket, etc. As an indicative example, a boron mass content of 16% or more can be achieved in the alloy, although this value can also be reduced by a few percent.

[0045] Alternatively, rather than being a single piece, each first flat bar 14a can be a single piece flat bar with a surface coating that includes boron. In this scenario, the single piece flat bar can be made from an aluminum alloy and the coating can be deposited by any known technique, such as, for example, high temperature or low temperature sputtering of boron carbide particles.

[0046] Preferably, the boron content is the same or substantially the same for all of the first flat bars 14 a of the basket 1 .

[0047] In the case of the second flat bars 14b, these bars 14b do not contain boron. Moreover, the second flat bars 14b do not contain any other neutron absorbing elements, i.e. are free from neutron absorbing elements. The term "neutron absorbing elements" denotes elements that have an effective cross section for thermal neutrons of more than 100 barns. As an illustrative example, the second flat bars 14b consist of an aluminum alloy that does not contain boron, gadolinium, hafnium, cadmium, indium, etc.

[0048] As regards the second flat bars 14b, these bars 14b are preferably made from an aluminium alloy and therefore do not contain boron.

[0049] In this regard, it is noted that "flat bar" denotes an element of flat overall shape, the thickness between both surfaces of which is a dimension smaller than the dimensions in the two other directions perpendicular to the thickness direction and perpendicular to each other. Furthermore, for each flat bar, the flat bar may consist of a single flat element or of an overlay of several flat elements in the thickness direction. According to another alternative, the flat bar may consist of a tubular element that houses a flat bar of complementary cross section. Preferably, each flat bar is solid or substantially solid except in the hollow zones forming the cutouts.

[0050] One of the particularities of the present invention is the judicious choice between the first flat bar 14a and the second flat bar 14b to make each of the partitions 9, 11 of the basket 1. Generally, the density of the partitions made from the first flat bar 14a containing boron is higher in the center than in the periphery of the basket. Also, some of the inner housings 4 and the peripheral housings 4' are made by combining the first flat bar 14a containing boron with the second flat bar 14b not containing boron.

[0051] More specifically, in at least one cross-section of the basket 1, such as cross-section P in FIG. 5, and preferably in all or substantially all of these cross-sections of the basket 1, the inner housing defining surface 10 of at least one of the N2 inner housings 4 is formed in part by a first flat bar 14a and a second flat bar 14b.

[0052] To more particularly illustrate this design, reference is made to the housing 4 in Figure 5, in which a fuel assembly 2 is shown. With respect to this housing 4, in the cross section of the basket, the inner housing-defining surface 10 is defined by four sides 10a, 10b, 10c, 10d, which are respectively defined by the second flat bar 14b and the third flat bar 14a.

[0053] More specifically, also in cross section, the first side 10a of the inner housing-defining surface 10 is made by a first surface 14b' of a second flat bar 14b. It should be noted that a second surface 14b" of said second flat bar 14b on the opposite side of the first surface 14b' also contributes to the formation of the inner housing-defining surface 10 of one or more other adjacent housings 4, 4' of the basket. Similarly, the second side 10b, the third side 10c and the fourth side 10d of the inner housing-defining surface 10 are made by the first surfaces 14a' of the three first flat bars 14a, respectively. Also, the second surfaces 14a" of each of these first flat bars 14a on the opposite side of the first surface 14a' also contribute to the formation of the inner housing-defining surface 10 of one or more other adjacent housings 4, 4' of the basket.

[0054] Thus, while some housings 4 located near or on the center of the basket 1 may be made only from the first flat bar 14a, housings 4 located closer to the periphery may be the result of a combination of one or more partitions made from the first flat bar 14a and one or more partitions made from the second flat bar 14b.

[0055] Thus, in the example of the loaded housing 4 of Fig. 5, the housing 4 consists of a single partition 9 made from the second flat bar 14b without boron and three partitions 9, 11 made from the first flat bar 14a with boron. Alternatively, for these inner housings 4 resulting from a combination of different types of partitions, the inner housing 4 can consist of two partitions 9, 11 made from the second flat bar 14b without boron and two partitions 9, 11 made from the first flat bar 14a with boron. In this latter case, the partitions of the same type can be directly consecutive and orthogonal in pairs or parallel in pairs.

[0056] As can be seen above, in a cross-section such as that of Figures 3 and 5, the inner defining surfaces 10 of the multiple housings 4, 4' take the form of four line segments 10a-10d corresponding respectively to the associated surfaces 14a', 14a", 14b', 14b" of the flat bars 14a, 14b.

[0057] Preferably, the combination of different types of dividing partitions 9, 11 concerns at least 50% of the N housings 4, 4' of the basket and at least 50% of the peripheral housings 4'. Furthermore, it is pointed out that some of these housings 4' are also closed by a peripheral partition 13, for example made from an aluminum alloy.

[0058] Such a combination of dividing partitions 9, 11, some containing boron and others not, reduces manufacturing costs and provides high performance in terms of maintaining subcriticality.

[0059] According to a second embodiment shown in Fig. 6, still complying with the general principles of the invention, the dividing partitions do not necessarily all have to be made with the same type of flat bars 14a, 14b. In fact, at least some of these dividing partitions 9, 11 are made by interleaving a first flat bar 14a and a second flat bar 14b along the stacking direction 20. In this case, structural elements 24 can be introduced into the stack between two immediately successive flat bars 14a, 14b as shown in Fig. 6. These structural elements 24, preferably made of steel, can take the form of bars that are inserted into the cutouts 16 of the flat bars 14a, 14b.

[0060] Naturally, those skilled in the art are able to make various modifications to the storage device 1 described above purely as a non-limiting example. [Explanation of symbols]

[0061] 1 Storage device, basket 2 Nuclear fuel assembly 3 Central Longitudinal Axis 4 Inner housing 4' Peripheral Housing 9. First Partition 10 Inner housing defining surface 10a First Side, Line Segment 10b Second side, line segment 10c Third side, line segment 10d Fourth side, line segment 11 Second Partition 13 Periphery Partition 14a First flat bar 14a' First surface 14a” Second Surface 14b Second flat bar 14b' First surface 14b” Second Surface 15 Tubes 16 Notch 20 Stacking Direction 24 Structural Elements 100 Transport 200 containers 202 Main Body 204 Side body 206 Bottom 208 Lid 210 Cavity 212 Shock absorbing cover

Claims

1. A storage device (1) for transporting and / or storing nuclear fuel assemblies (2), the storage device being intended to be housed in a cavity of a container (200) for transporting and / or storing the nuclear fuel assemblies and comprising N adjacent housings (4, 4') each intended to receive a nuclear fuel assembly (2), at least some (N) of the N adjacent housings being made from flat bars (14a, 14b) with cutouts, interlocked and stacked along a stacking direction (20) that is parallel to a central longitudinal axis (3) of the storage device, In at least one cross-section of the storage device passing through N adjacent housings (4, 4'), at least one of the adjacent housings has an inner housing-defining surface (10), or each of a plurality of the N adjacent housings (4, 4') has an inner housing-defining surface (10), the inner housing-defining surface (10) being: a first surface (14a') of a first flat bar (14a) having a notch made with boron, the second surface (14a'') of said first flat bar (14a) on the opposite side of said first surface (14a') contributing to the formation of said inner housing-defining surface (10) of one or more other of said N adjacent housings (4, 4'); a first surface (14b') of a second flat bar (14b) having a notch made without boron, the second surface (14b'') of the second flat bar (14b) on the opposite side of the first surface (14b') contributing to the formation of the inner housing-defining surface (10) of one or more other of the N adjacent housings (4, 4'); A storage device (1), characterized in that it is formed in part by:

2. In each of a plurality of cross sections of the storage device passing through each of N adjacent housings (4, 4'), at least one of the adjacent housings has an inner housing-defining surface (10), or each of a plurality of the N adjacent housings has an inner housing-defining surface (10), the inner housing-defining surface (10) being: a first surface (14a') of a first flat bar (14a) having a notch made with boron, the second surface (14a'') of said first flat bar (14a) on the opposite side of said first surface (14a') contributing to the formation of said inner housing-defining surface (10) of one or more other of said N adjacent housings (4, 4'); a first surface (14b') of a second flat bar (14b) having a notch made without boron, the second surface (14b'') of the second flat bar (14b) on the opposite side of the first surface (14b') contributing to the formation of the inner housing-defining surface (10) of one or more other of the N adjacent housings (4, 4'); 2. The storage device of claim 1, formed in part by:

3. said N adjacent housings (4, 4') being divided into a peripheral housing (4') and an inner housing (4); and Within one cross-section of the storage device passing through N adjacent housings (4, 4'), or within each of a plurality of cross-sections of the storage device passing through each of N adjacent housings (4, 4'), at least 50% of the peripheral housings (4') each have an inner housing-defining surface (10), the inner housing-defining surface (10) being: a first surface (14a') of a first flat bar (14a) having a notch made with boron, the second surface (14a'') of said first flat bar (14a) on the opposite side of said first surface (14a') contributing to the formation of said inner housing-defining surface (10) of one or more other of said N adjacent housings (4, 4'); a first surface (14b') of a second flat bar (14b) having a notch made without boron, the second surface (14b'') of the second flat bar (14b) on the opposite side of the first surface (14b') contributing to the formation of the inner housing-defining surface (10) of one or more other of the N adjacent housings (4, 4'); 2. The storage device of claim 1, formed in part by:

4. Within one cross-section of the storage device passing through N adjacent housings (4, 4'), or within each of a plurality of cross-sections of the storage device passing through each of the N adjacent housings (4, 4'), at least 50% of the N adjacent housings each have an inner housing-defining surface (10), the inner housing-defining surface (10) being: a first surface (14a') of a first flat bar (14a) having a notch made with boron, the second surface (14a'') of said first flat bar (14a) on the opposite side of said first surface (14a') contributing to the formation of said inner housing-defining surface (10) of one or more other of said N adjacent housings (4, 4'); a first surface (14b') of a second flat bar (14b) having a notch made without boron, the second surface (14b'') of the second flat bar (14b) on the opposite side of the first surface (14b') contributing to the formation of the inner housing-defining surface (10) of one or more other of the N adjacent housings (4, 4'); 2. The storage device of claim 1, formed in part by:

5. Within one cross-section of the storage device passing through N adjacent housings (4, 4'), or within each of a plurality of cross-sections of the storage device passing through each of the N adjacent housings (4, 4'), at least one of the adjacent housings has an inner housing-defining surface (10) having a generally square or rectangular cross-section, or each of a plurality of the N adjacent housings has an inner housing-defining surface (10) having a generally square or rectangular cross-section, the inner housing-defining surface (10) being a first surface (14a') of a first flat bar (14a) having a notch made with boron, the second surface (14a'') of said first flat bar (14a) on the opposite side of said first surface (14a') contributing to the formation of said inner housing-defining surface (10) of one or more other of said N adjacent housings (4, 4'); a first surface (14b') of a second flat bar (14b) having a notch made without boron, the second surface (14b'') of the second flat bar (14b) opposite the first surface (14b') contributing to the formation of the inner housing-defining surface (10) of one or more other of the N adjacent housings (4, 4'); Two other flat bars (14a, 14b) with cutouts; and said first flat bar (14a), said second flat bar (14b) and said two other flat bars (14a, 14b) respectively form four sides (10a-10d) of said inner housing-defining surface (10) having a generally square or rectangular cross-section; The storage device of claim 1 ,

6. The two other flat bars (14a, 14b) with cutouts are Two first flat bars (14a) with notches made with boron, or Two second flat bars (14b) with notches made without boron, or A first flat bar (14a) with a notch made with boron and a second flat bar (14b) with a notch made without boron.

6. The storage device of claim 5, wherein each of the storage devices is formed by

7. 2. The storage device according to claim 1, characterized in that the flat bars (14a, 14b) with cutouts stacked and interlocked inside the storage device are either a first flat bar (14a) with cutouts made with boron, preferably with the same boron content, or a second flat bar (14b) with cutouts made without boron.

8. 2. The storage device according to claim 1, characterized in that the at least one first flat bar (14a) with the cutout is made in a single piece from an aluminium alloy, preferably containing boron, and / or the at least one first flat bar (14a) with the cutout comprises a coating, preferably containing boron, applied onto an aluminium alloy material.

9. 2. The storage device according to claim 1, characterized in that at least one second flat bar (14b) with a notch is made from a boron-free aluminum alloy.

10. The stacked and interlocked flat bars (14a, 14b) together form partitions (9, 11) for dividing adjacent housings (4, 4'), each partition extending along or substantially along the entire height of the storage device, each partition comprising: by stacking a first flat bar (14a) with a notch, or by stacking a second flat bar (14b) with a notch, or by alternating first flat bars (14a) and second flat bars (14b) with cutouts, or The alternating arrangement of first and second flat bars (14a) and (14b) having cutouts, wherein a structural element (24), preferably made of steel, is further arranged between the first and second flat bars (14a) and (14b).

2. The storage device of claim 1, wherein the storage device is formed.

11. A vessel (200) for storing and / or transporting nuclear fuel assemblies, said vessel comprising a cavity (210) in which the storage device (1) according to claim 1 is accommodated.

12. A transport (100) comprising a container (200) according to claim 11 and nuclear fuel assemblies (2) arranged in adjacent housings (4, 4') of a storage device (1) of said container (200).

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