Packaging for transporting and / or storing radioactive materials, comprising an improved lid fastening system
The packaging system addresses seal maintenance issues by using a fastening device with active and passive zones to manage stress distribution, ensuring airtightness during axial drops.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ORANO NUCLEAR PACKAGES & SERVICES
- Filing Date
- 2025-12-03
- Publication Date
- 2026-06-11
Smart Images
Figure EP2025085225_11062026_PF_FP_ABST
Abstract
Description
[0001] 44501 AP-P
[0002] 1
[0003] Packaging for the transport and / or storage of radioactive materials, featuring an improved lid fastening system
[0004] TECHNICAL FIELD
[0005] 5 The present invention relates to the field of packaging for the transport and / or storage of radioactive materials, and to that of packages comprising such packaging, as well as radioactive materials housed in a containment enclosure defined by a packaging body.
[0006] The packaging in question is of the type including a removable lid, such as for example
[0007] 10 used for the transport of nuclear fuel assemblies. Within the containment area delimited by the packaging, a storage device can be arranged to hold one or more radioactive items, these being nuclear fuel assemblies, fresh or irradiated, containers / casings of vitrified waste or technological waste, containers / casings of shells and end caps, or cases for the transport of powder (PuO2 powder for example).
[0008] The invention relates more specifically to a system for fixing the lid to the side body of the packaging.
[0009] PREVIOUS STATE OF THE ART
[0010] A package for the storage and / or transport of radioactive materials includes
[0011] 20. Generally, as a sealed outer casing, a package has a body consisting of a side panel, a base, and a removable lid. These parts of the body define a sealed cavity, called a containment enclosure, for housing radioactive materials. A storage device, usually called a storage basket, may also be used to help maintain the containment.
[0012] 25 of the radioactive materials inside the containment structure. When such a basket is used, the assembly consisting of the basket and the radioactive materials is called the radioactive content. 44501 AP-P
[0013] 2
[0014] The safety demonstration of the packaging containing radioactive material is based in particular on regulatory drop tests. Thus, during an axial drop of nine meters onto a shock-absorbing head cover over the packaging lid, the radioactive material can move axially within the containment structure towards the lid.
[0015] 5. Due to axial play between the radioactive contents and the packaging lid, as the head-shocked cover collapses, the radioactive contents can impact this same lid during this fall, known as "axial fall." This generates significant delayed forces in the fastening means of the removable packaging lid, due to the delayed movement of the radioactive contents within the containment structure. In particular, the lid fastening means, such as screws, are subjected to considerable stress by the deformed lid.
[0016] Maintaining the airtight seal of the packaging's containment structure during an axial drop may require the implementation of measures designed to limit the forces transmitted by radioactive materials to the lid. This could, for example, involve a
[0017] 15. An internal shock-absorbing system, located within the containment structure, between the lid and the radioactive contents. This system is also known as an internal shock-absorbing system. Numerous solutions for implementing this system have already been proposed in the prior art.
[0018] However, the available space between the lid and the radioactive contents may sometimes prove insufficient to accommodate an internal shock absorber. Even when such a shock absorber can be fitted, the space allocated to it may be inadequate for it to sufficiently limit the effects of the radioactive contents impacting the lid, which moves with a time delay within the containment structure, should the package fall towards the lid.
[0019] 25. Consequently, even with the presence of an internal shock absorber, the delayed impact caused by the radioactive contents on the inner surface of the lid can lead to deformation, resulting in a sort of outward bending of the packaging in the axial direction. This deformation of the lid places significant stress on the fastening screws, which may in turn be at risk of deformation due to the moment of 44501 AP-P
[0020] 3. Flexion induced by the lid, and thereby cause a risk of breach of seal between the lid and the lateral body of packaging.
[0021] Such a risk also exists if the packaging is dropped, causing significant axial forces on the outer face of the lid, for example, applied by the hood
[0022] 5. External shock absorber covering the lid. Such a situation causes the latter to deform by undergoing a kind of bending, towards the inside of the containment enclosure.
[0023] DESCRIPTION OF THE INVENTION
[0024] To address at least partially the drawbacks mentioned above, the invention first relates to packaging for the transport and / or storage of radioactive materials, comprising a packaging body formed by a side packaging body, a packaging base, and a removable lid mounted on an axial end of the side packaging body, using fastening means comprising at least one fastening device, this device having a bearing member with a load-bearing surface applying, by contact with a receiving surface of the fastening means provided on the
[0025] 15 lid, a clamping force of the lid on the lateral body of the packaging, the clamping force being oriented along a clamping direction parallel to a longitudinal central axis of the packaging passing through the lid and the bottom of the packaging body, the receiving surface being traversed by a passage hole through which the fastening device passes, the passage hole being arranged on a peripheral area of the lid.
[0026] According to the invention, the stressing surface comprises a first active zone, in contact with a second active zone of the receiving surface, and a first passive zone opposite and at a distance from a second passive zone of the receiving surface, along the direction of contact. Furthermore, in a view along the direction of contact, the second
[0027] 25. The passive zone extends at least to an outer periphery of the bearing surface of the support member, and preferably beyond this outer periphery, the first passive zone being entirely circumscribed within an angular sector of the bearing surface, centered on a longitudinal central axis of the fastening device and less than 180°. 44501 AP-P
[0028] 4
[0029] The invention advantageously allows, locally at the level of the second passive zone of the receiving surface provided on the lid, local deformation of the lid in the event of a fall, while limiting the mechanical stresses on the fastening means. The risks of permanent deformation of the lid fastening devices, as well as the risks
[0030] The five potential points of leakage between the lid and the side of the packaging are advantageously reduced. The airtightness of the containment enclosure can thus be maintained without the need to increase the number and / or size of the lid fastening devices.
[0031] The invention preferably provides for the implementation of one or more of the
[0032] The following 10 optional features, taken individually or in combination.
[0033] Preferably, the second active and passive zones are separated by a break in level on the receiving surface of the cover. Alternatively, the receiving surface of the cover can remain flat. The spacing between the first and second passive zones can then be achieved by creating the support element with an assembly consisting of a screw head and a truncated washer bearing against the receiving surface of the cover.
[0034] Preferably, the first passive zone and the second passive zone are separated by a gap in the direction of application, with a value greater than or equal to 0.2 mm. In this regard, it is noted that in all the embodiments considered, the aforementioned gap / spacing,
[0035] 20 located axially between the first and second passive zones, can remain empty or possibly be filled by an element comprising a filling material, presenting a lower crushing stress than that of the material(s) of the cover and the fixing device.
[0036] Preferably, in the view along the direction of the plate, the first passive zone of the stress surface of the support member has an area equal to at least 5% of the total area of the stress surface of the support member with respect to the receiving surface, and more preferably to at least 10% or 15% of this total area, while remaining less than 50% of this total area.
[0037] Preferably, the second passive zone of the receiving surface opens into the hole
[0038] 30 mm opening through which the fastening device passes. 44501 AP-P
[0039] 5
[0040] Preferably, the second passive zone of the lid receiving surface, its associated fixing device, and the longitudinal central axis of this packaging follow one another in a radial direction of the packaging, preferably being aligned with each other along this same direction.
[0041] 5. According to a preferred embodiment of the invention, the second passive zone of the lid's receiving surface is arranged, in a radial direction of the packaging, between its associated fastening device and the longitudinal central axis of the packaging. This addresses the problem of delayed impact caused by the radioactive content on the inner face of the lid, which could lead to deformation.
[0042] 10 undergoing a sort of outward bending of the packaging, in the axial direction. Alternatively, the radioactive content could consist solely of radioactive materials, without departing from the scope of the invention.
[0043] According to another preferred embodiment of the invention, the second passive zone of the lid receiving surface is arranged, in a radial direction of the packaging,
[0044] 15 radially outwards relative to its associated fastening device. This addresses the issue of external impact on the outer face of the lid, which could cause it to deform by undergoing a kind of inward bending towards the packaging, in the axial direction. Such stress on the lid could, for example, result from an external shock-absorbing cover, if the packaging is dropped onto this surface.
[0045] 20 hood. Preferably, the second passive zone of the cover receiving surface extends to a periphery of the cover.
[0046] It is noted that the two preferred embodiments just described can be combined within the same packaging lid, for example by providing diametrically opposed recesses on the receiving surface on either side of the fastening devices, such as screws.
[0047] These two modes could also be combined by providing packaging with two separate lids, one after the other along the axial direction, the inner lid then preferably being equipped with the principle according to the first mode described above, and the outer lid preferably being equipped with the principle according to the second mode described
[0048] 30 above. 44501 AP-P
[0049] 6
[0050] According to a preferred embodiment of the invention, the second passive zone of the lid receiving surface has the form of a material recess on the lid receiving surface.
[0051] According to another preferred embodiment of the invention, the lid comprises a body
[0052] 5 main cover, as well as a support device for the fixing device mounted on the cover body, and the second passive area of the receiving surface is provided on the cover body, and the second active area of the receiving surface is provided on the support device, which is preferably a removable wear part.
[0053] Preferably, the fastening device includes a washer, and the entire washer forms at least part of the support member, and preferably the entire support member, this washer being preferably traversed by an elongated fastening member, such as a screw.
[0054] Preferably, the fastening device is a screw, or an assembly consisting of a screw and a washer, and the bearing member is the screw head, or the washer, or an assembly consisting of the
[0055] 15. Screw head and washer. As an alternative to screws, tie rods or studs fitted with nuts, or equivalent means, preferably elongated fixing elements, can be used.
[0056] Preferably, the fastening means comprise a plurality of fastening devices spaced circumferentially from each other, at least some of them, or even all of them, each implementing the principle of the invention.
[0057] Preferably, the packaging includes an internal shock absorber, intended to protect the lid and arranged inside a containment enclosure for radioactive materials, the containment enclosure being defined by the packaging body.
[0058] Finally, the invention also relates to a package comprising such packaging, as well as
[0059] 25 of the radioactive materials arranged in the packaging.
[0060] Other advantages and features of the invention will appear in the detailed, non-limiting description below.
[0061] BRIEF DESCRIPTION OF THE DRAWINGS
[0062] This description will be made with reference to the attached drawings, among which are: 44501 AP-P
[0063] 7
[0064] [Fig. 1] represents a schematic axial cross-sectional view of a package according to the invention;
[0065] [Fig. 2] represents a partial axial cross-sectional view of the packaging belonging to the parcel shown in the previous figure, and showing one of the devices for fixing the packaging lid to the packaging body, the packaging being in the form of a mode
[0066] 5 of preferred embodiment of the invention, this view also corresponding to a section taken along the line ll-ll of figure 3;
[0067] [Fig. 3] represents a view along the direction of the lid's contact with the side body of the packaging, showing the cooperation between different areas of a stress surface provided on a support member of the fastening device shown in the previous figure, and a receiving surface provided on the lid;
[0068] [Fig. 4] is a view similar to that of figure 3, showing another preferred embodiment of the invention;
[0069] [Fig. 5] is a view similar to that of figure 3, showing another preferred embodiment of the invention;
[0070] 15 [Fig. 6] is a view similar to that of figure 2, showing another preferred embodiment of the invention;
[0071] [Fig. 7] is a view similar to that of figure 2, showing another preferred embodiment of the invention;
[0072] [Fig. 8] is a view similar to that of figure 2, showing another preferred embodiment of the invention;
[0073] [Fig. 9] represents a partial perspective view of the packaging belonging to the parcel shown in the previous figure, the packaging being in the form of another preferred embodiment of the invention;
[0074] [Fig. 10] represents a view similar to that of figure 9, showing another mode of
[0075] 25 preferred realization of the invention;
[0076] [Fig. 11] is a view similar to that of figure 2, showing another preferred embodiment of the invention;
[0077] [Fig. 12] is a view similar to that of Figure 2, showing yet another preferred embodiment of the invention. 44501 AP-P
[0078] 8
[0079] DETAILED DESCRIPTION OF SPECIFIC METHODS OF IMPLEMENTATION
[0080] With reference first to Figure 1, a package 100 for the storage and / or transport of radioactive materials 12 is shown. It comprises, firstly, a package 1, having a packaging body formed by a side body 2, a base 4 and a removable lid 6
[0081] 5 closing an opening in the packaging opposite the base 4. The packaging has a central longitudinal axis 8 around which the side panel 2 extends, this axis 8 passing through the lid 6 and the base 4 respectively arranged at the axial ends of the side panel 2 of the packaging. As schematically illustrated in Figure 1, the base 4 can be made as a single piece with the side panel 2. The lid 6, for its part,
[0082] 10 is attached to the opposite axial end of the lateral body 2, corresponding to the upper axial end in the vertical storage position of the package, as shown in Figure 1. This lid 6 is secured by means of fastening means comprising a plurality of fastening devices 14 spaced circumferentially from one another around the periphery of the lid, so as to form an annular row of devices 14. In the cross-sectional view of Figure 1, only two fastening devices 14 are shown schematically. Their design and arrangement are specific to the invention, and various preferred embodiments will be described with reference to the following figures. Preferably, several of these fastening devices 14 have the design specific to the invention, and even more
[0083] 20 preferably all of them.
[0084] As will be detailed below, each fastening device 14 is preferably a screw, or an assembly consisting of a screw and a washer, this fastening device being arranged on a peripheral area of the cover. Furthermore, such a fastening device 14 includes a bearing member on the cover 6, this bearing member being the washer, the screw head, or an assembly consisting of the screw head and the washer, when the latter is truncated.
[0085] The side body 2, the cover 6, and the base 4 define a containment enclosure 10, used to house the radioactive materials 12. The cover 6 and the base 4 thus form the two opposing axial sealing elements of the containment enclosure 10, which is
[0086] 30 watertight thanks to the implementation of one or more sealing joints 11, clamped 44501 AP-P
[0087] 9 axially between the lid 6 and the corresponding axial end of the side body of the packaging 2. Preferably, the sealing gasket 11 is located radially inwards relative to the annular ring of fastening devices 14. In this regard, in Figure 1, a radial direction 15 of the packaging is shown, relative to its axis
[0088] 5 central longitudinal 8, as well as the axial / longitudinal direction 17 of this packaging, parallel to the axis 8. It is noted that the axial direction 17 of the packaging also corresponds to a plating direction of the lid 6 on the lateral body of packaging 2, this plating being carried out by the fastening devices 14. When such a basket is implemented, the assembly consisting of the basket and the radioactive materials is called radioactive content.
[0089] The radioactive materials 12, represented schematically only, are preferentially held laterally in the containment enclosure 10 by a storage basket.
[0090] Radioactive materials can consist of fuel assemblies
[0091] 15 nuclear, fresh or irradiated. Instead of nuclear fuel assemblies, radioactive materials, within the meaning of the invention, could alternatively be vitrified waste containers / casings, shell and end containers / casings, or cases for transporting powder.
[0092] As shown in dotted lines in Figure 1, at opposite ends of the package considered along axis 8, the package 1 can be equipped with external shock-absorbing covers 20, protecting respectively the removable cover 6 and the base 4 of the package.
[0093] The package 1 is also equipped with an internal shock absorber 22, shown schematically only in Figure 1, and which can be made in any form known in the prior art. This internal shock absorber 22 is housed within the enclosure of
[0094] 25 Containment 12, axially between an inner face 24 of the lid 6, and an axial end surface 26 of the radioactive content. Preferably, the internal damper 22 is fixed to the inner face 24 of the lid 6, for example by means of screws or by welding. It could alternatively be fixed to the axial end surface 26 of the radioactive content, or be freely arranged between this radioactive content and the lid. 44501 AP-P
[0095] 10
[0096] Thus, the internal damping system 22 can be arranged in several ways between the radioactive content 12 and its associated axial sealing element, formed by the removable cover 6.
[0097] In a preferred embodiment shown in Figures 2 and 3, one is shown
[0098] 5 of the fastening devices comprising the screw 14 and a support washer 63, with a surface area greater than or equal to that of the screw head 30, and covering the latter entirely, according to the facing direction 17. In a similar embodiment, but not shown, this support member could be directly the screw head 30.
[0099] The surface under the thrust washer, forming the aforementioned support member, is a load-bearing surface 32, here annular in shape and centered on an axis 34 of the screw. When the screw 14 is tightened into a threaded hole 36 in the side packaging body, the load-bearing surface 32 of the thrust washer applies, by contact with a receiving surface 42 for the fastening means provided on the cover 6, a clamping force of the cover 6 against the upper axial end of the side packaging body 2. Consequently, the receiving surface 42
[0100] 15 provided on the cover is located axially opposite the stress surface 32 provided on the support washer 63, while preferably extending locally beyond this surface 32 in the radial direction 15, as will be described below.
[0101] The receiving surface 42 is traversed by a through hole 44 through the cover 6. This hole 44 is traversed by a shaft of the screw 14, and is therefore also arranged on a peripheral area 46 of the cover 6, always with reference to the axis 8.
[0102] One of the distinctive features of the invention lies in the fact that the stress surface 32 comprises a first active zone ZA1, in contact with a second active zone ZA2 of the receiving surface 42. It is these two active zones of surfaces 32 and 42 that enable the application of the clamping force on the cover. Furthermore, the stress surface 32
[0103] 25 comprises a first passive zone ZP1 opposite and at a distance from a second passive zone ZP2 of the receiving surface 42, according to the tackling direction 17.
[0104] In Figure 3, the first active zone ZA1 is represented by dots ".", while the first passive zone ZP1 is represented by double dots ":". The boundary between these two adjacent zones ZA1 and ZP1 is also represented by double dots. From 44501 AP-P
[0105] 11 Similarly, the second active zone ZA2 is represented by dashes “-”, while the second passive zone ZP2 is represented by double dashes “=”.
[0106] Furthermore, for greater clarity, the second passive zone ZP2 is shown hatched, with a different hatching pattern than the second active zone ZA2. These last two
[0107] 5 zones ZA2, ZP2 are also adjacent, with their boundary marked by double dashes.
[0108] In this preferred embodiment, the stress surface 32, which is thus formed by the first two zones ZA1, ZP1, has a ring shape centered on the screw axis 34. The boundary between these two zones ZA1, ZP1 can take the form of a straight line
[0109] 10 passing through the ring, without going through its central hollow zone. In this regard, it is noted that, still in the view of Figure 3, taken along the plating direction 17, the first passive zone ZP1 of the stress surface 32 has an area equal to at least 5% of the total area of this stress surface. It is specified that this total area of the stress surface 32, preferably planar, corresponds to the sum of the area of the first passive zone ZP1 and the area of the first active zone ZA1. More preferably, the area of the first passive zone ZP1 corresponds to at least 10% or 15% of this total area, while remaining less than 50% of this total area, and even more preferably less than or equal to 40%.
[0110] More generally, the first passive zone ZP1 is entirely circumscribed within
[0111] 20 an angular sector Sa of the stress surface 32, centered on the axis 34 and less than 180°. In other words, the passive zone ZP1 extends only to a limited extent around the axis 34.
[0112] The receiving surface 42, which is thus made up of the two second zones ZA2 and ZP2, has a more complex shape than the stress surface 32 of the support washer 63. Indeed, while the second active zone ZA2 has the same shape as the first active zone ZA1, that is, a truncated ring shape at its outer periphery, the second passive zone ZP2, hatched in Figure 3, differs from the first passive zone ZP1. This passive zone ZP2 corresponds to the portion removed from the truncated ring, equivalent to the surface area of the passive zone ZP1, plus an additional
[0113] 30 second part which preferably extends radially beyond the outer periphery of 44501 AP-P
[0114] 12 the stress surface 32 of the support washer 63, in the direction of the axis 8. Indeed, in this preferred embodiment, the second passive zone ZP2 is arranged, in the radial direction 15, between the shank of the screw 14 and the axis 8. As shown schematically in Figure 3, the shape of the second passive zone ZP2 can thus correspond to that of a disk
[0115] 5 truncated at its periphery, with the truncation line being identical to the line defining the boundary between the first active zone ZA1 and the first passive zone ZP1.
[0116] Still within the framework of this preferred embodiment of the invention, the second passive zone ZP2 is in the form of a base of a material recess 50, made on the receiving surface 42 of the lid, forming an integral part of its external face.
[0117] In other words, the support washer 63 is partially aligned axially with the recess 50 on the cover, so that only a portion of the support washer 63 is used to transmit the clamping force to the cover 6. At this recess 50, an axial gap 52 is therefore observed in the clamping direction 17 between the first passive zone ZP1 and the second passive zone ZP2. This gap 52, with a value greater than or equal to 0.2 mm, thus corresponds to the depth of the recess 50. Moreover, it is noted that the presence of the latter marks a level break 54 between the second active and passive zones ZA2, ZP2, which are therefore separated from each other at one side of the recess forming this level break, on the receiving surface 42 of the cover 6.
[0118] 20 In the event of a drop in the packaging, the two passive zones ZP1 and ZP2 of surfaces 32 and 42 allow the lid 6 to deform outwards following an impact from the radioactive contents, drastically limiting the bending moment induced in the barrels of the fixing screws 14. Indeed, during such a deformation of the lid, the support washer 63 and, consequently, the end of the screw head 30, which are located radially inwards towards the axis 8, are not, or only minimally, subjected to stress by the deformed part of the lid, since the recess 50 avoids / limits contact with this end of the head of the support washer. The associated risks of leakage at the seal 11, between the lid 6 and the side body of the packaging 2, in the event of a drop in the packaging and outward deformation of the lid, are thereby mitigated.
[0119] 30 advantageously reduced. 44501 AP-P
[0120] 13
[0121] Figures 4 and 5 represent other preferred embodiments, similar to the previous one.
[0122] In the embodiment shown in Figure 4, the loading surfaces 32 and receiving surfaces 42 have the same general shapes as in the previous embodiment. Only the following changes
[0123] 5 the boundary between the two zones ZA1, ZP1, and the boundary between the two zones ZA2, ZP2. Indeed, these two boundaries, which are always superimposed in the view according to the plating direction 17, are closer to the screw axis 34 since the second passive zone ZP2 opens into the passage hole 44.
[0124] In the preferred embodiment of Figure 5, the second passive zone ZP2 opens
[0125] 10 also in the passage hole 44. But its shape differs in that it no longer corresponds to a truncated disc eccentric to the screw axis 34, but to an angular sector of a ring centered or substantially centered on this same screw axis 34.
[0126] In the preferred embodiment of Figure 6, the cover 6 comprises a main cover body 6a and a screw support device 6b mounted on the main cover body 6a. This mounting is achieved, for example, by storing the support device 6b between the screw head 30 and the main cover body 6a in a recess 60 on the outer face of the periphery of this body. The support device 6b may be a ring or a spacer, centered on the screw axis 34, and through which the screw shank passes. It is preferably a wear part, easily replaceable. The device
[0127] Support element 6b is therefore partially embedded in the main body of the cover 6a, while projecting upwards from the outer face of the main body 6a. The axial projection distance of the support element 6b, which also corresponds to the gap 52, is thus established between the second passive zone ZP2 provided on the main body 6a, and the second active zone ZA2 provided at the upper end of the support element 6b. Furthermore, the level break 54 between the second active and passive zones ZA2, ZP2 corresponds to the outer lateral surface of the support element 6b.
[0128] In the preferred embodiment of Figure 7, the fastening device comprises the screw 14 and a truncated thrust washer 62, such that the bearing member is constituted by the assembly formed by the screw head 30 and the truncated washer 62. In this embodiment, the
[0129] 30 washer 62 does not cover the entire screw head 30 according to the plating direction 44501 AP-P
[0130] 14
[0131] 17, but part of this screw head 30 is thus located opposite and at a distance from the receiving surface 42, which can be made flat on the cover 6. It is this part of the screw head 30 that forms the first passive zone ZP1 of the loading surface 32, while the rest of this surface 32, namely the first active zone ZA1, is formed by
[0132] 5. The surface of the truncated washer 62 rests against the cover. As previously stated, the receiving surface 42, which includes the two zones ZA2, ZP2, can be flat and lie in the plane of the outer face of the cover 6. The clearance 52 is then dictated by the thickness of the truncated washer 62.
[0133] For illustrative purposes, it is noted that in a similar embodiment, but not shown,
[0134] 10 The truncated washer 62 can be replaced by a conventional washer, with an outside diameter strictly smaller than that of the screw head 30.
[0135] The preferred embodiment of Figure 8 is similar to that of Figures 2 and 3. The only difference lies in filling the recess 50 with an element 64 comprising a filling material that exhibits a lower crushing strength than the material(s) of the cover 6 and the screw 14. For example, this could be a watertight element comprising polyurethane foam, or any other material known to perform the filling function while limiting the transmission of forces towards the bearing member of the fastening device. In this respect, this filling principle is applicable to all embodiments of the invention, in particular to
[0136] 20 those implementing a support member formed by any support washer 63 interposed between the screw head 30 and the cover 6, as shown in Figure 9. As an alternative to filling, a thin sheet welded around its entire perimeter can be used to cover the recess 50, and facilitate its decontamination.
[0137] The preferred embodiment shown in Figure 9 differs from the previous ones in that the second passive zone ZP2 of the receiving surface 42 is arranged, in the radial direction 15, outwards relative to the fixing screw 14. Here, the screw head 30 is received in a counterbore 66 in the outer face of the cover 6, and the bottom of the counterbore 66 forms the two second zones ZA2, ZP2, which are preferably coplanar. This embodiment has been shown with a bearing element formed by the combination of the screw head 30 and a truncated washer.
[0138] 30 62, but any other implementation remains possible. Counterbore 66 is preferably 44501 AP-P
[0139] 15 also open radially outwards, so that the second passive zone ZP2 of the receiving surface 42 extends to a periphery of the cover 6.
[0140] The radially outward arrangement of the second passive zone ZP2 addresses the issue of external impact on the outer face of the cover.
[0141] 5, which can cause the latter to deform by undergoing a kind of inward bending of the packaging, in the axial direction. Such stress on the lid 6 can, for example, originate from the external shock-absorbing cover (not shown), when the packaging is dropped onto this cover.
[0142] The preferred embodiment of Figure 10 is based on the same principle, with a
[0143] 10 second passive zone ZP2 opening radially to the outside. Here, the receiving surface 42 is provided on a hollowed annular part 70 on the periphery of the cover 6.
[0144] The preferred embodiment shown in Figure 11 is very similar to that of Figure 2, except that the screw head 30 is arranged in a counterbore 66 in the cover. Other arrangements among those described previously can be considered for the screw 14, the distinctive feature of this embodiment being the design of the cover 6. This cover includes, firstly, a sealing plug 6c, which delimits the containment chamber 10. The cover 6 also includes a fixing flange 6d, which partially overlaps the plug 6c axially. The screw 14 cooperates with a peripheral portion of this flange 6d in order to fix the flange 6d to the lateral packaging body 2.
[0145] 20 Tightening the flange with the screws 14 causes the cap 6c of the lid to be pressed against the side body of the packaging 2, and the seal 11 arranged between the cap 6c and the side body of the packaging to be crushed.
[0146] Finally, the preferred embodiment of Figure 12 provides for packaging with two lids 6. The two lids are arranged in succession along the plating direction 17, so as to conventionally form an inner or primary lid on the side of the containment enclosure 10, and an outer or secondary lid on the opposite side. The two lids 6 are fixed by means of fastening devices 14 of any design described above. However, preferably, the primary lid is more susceptible to outward deformation of the
[0147] 30. Due to the forces caused by radioactive content in the event of a fall, the arrangements 44501 AP-P
[0148] 16 of the selected are preferentially those described with reference to figures 2 to 8. In these modes, the second passive zone ZP2 of the receiving surface of the cover is effectively arranged between the screw 14 and the axis 8, which allows the aforementioned deformation of the cover, without risking a break in the seal at the joint 11.
[0149] 5 Conversely, since the secondary cover is more subject to the risk of inward deformation due to the forces caused by the external shock-absorbing cover in the event of a fall, the arrangements retained are preferentially those described with reference to figures 9 and 10. In these modes, the second passive zone ZP2 of the receiving surface of the cover is indeed arranged radially outwards with respect to the screw 14, which 10 allows the aforementioned deformation of the cover, without risking a break in the seal at the joint 11.
[0150] Of course, various modifications can be made by a person skilled in the art to the invention just described, solely by way of non-limiting examples, the scope of which is defined by the appended claims. In particular, the characteristics of the 15 different embodiments presented above are interchangeable and combinable.
Claims
44501 AP-P 17 DEMANDS 1. Packaging (1) for the transport and / or storage of radioactive materials (12), 5 comprising a packaging body formed by a side packaging body (2), a packaging base (4), and a removable lid (6) mounted on an axial end of the side packaging body, by means of fastening means comprising at least one fastening device (14), the latter having a support member (30, 62) having a load-bearing surface (32) applying, by contact on a receiving surface (42) of the means of 10. Fixing provided on the lid, a clamping force of the lid (6) on the lateral body of the packaging (2), the clamping force being oriented along a clamping direction (17) parallel to a longitudinal central axis (8) of the packaging passing through the lid (6) and the bottom (4) of the packaging body, the receiving surface (42) being traversed by a passage hole (44) through which passes the fixing device (14), the passage hole being arranged on a peripheral area (46) of the lid, characterized in that the stressing surface (32) comprises a first active zone (ZA1), in contact with a second active zone (ZA2) of the receiving surface (42), as well as a first passive zone (ZP1) opposite and at a distance from a second passive zone (ZP2) of the receiving surface (42), along the clamping direction (17), 20 and in that, in a view along the plating direction (17), the second passive zone (ZP2) extends at least to an outer periphery of the stress surface (32) of the support member (30, 62), and preferably beyond this outer periphery, the first passive zone (ZP1) being entirely circumscribed within an angular sector (Sa) of the stress surface (32), centered on a central longitudinal axis (34) of the device 25 fixing (14) and less than 180°.
2. Packaging according to claim 1, characterized in that the second active and passive zones (ZA2, ZP2) are separated from each other by a level break (54) provided on the receiving surface (42) of the lid (6). 44501 AP-P 18 3. Packaging according to claim 1 or 2, characterized in that the first passive zone (ZP1) and the second passive zone (ZP2) are separated by a gap (52) along the plating direction (17), of a value greater than or equal to 0.2 mm.
4. Packaging according to any one of the preceding claims, characterized in that 5 in the view along the direction of the plating (17), the first passive zone (ZP1) of the stress surface (32) of the support member (30, 62) has an area equal to at least 5% of the total area of the stress surface (32) of the support member with respect to the receiving surface (42), and more preferably to at least 10% or 15% of this total area, while remaining less than 50% of this total area. 10 5. Packaging according to any one of the preceding claims, characterized in that the second passive zone (ZP2) of the receiving surface (42) opens into the passage hole (44) through which the fastening device (14) passes.
6. Packaging according to any one of the preceding claims, characterized in that the second passive zone (ZP2) of the receiving surface (42) of the lid (6), its device 15 associated fixing (14), and the longitudinal central axis (8) of this packaging follow one another in a radial direction (15) of the packaging.
7. Packaging according to claim 6, characterized in that the second passive zone (ZP2) of the receiving surface (42) of the lid (6) is arranged, in the radial direction (15) of the packaging, between its associated fastening device (14), and the longitudinal central axis (8) of this packaging.
8. Packaging according to claim 6, characterized in that the second passive zone (ZP2) of the receiving surface (42) of the lid (6) is arranged, in the radial direction (15) of the packaging, radially outwards relative to its associated fastening device (14). 25 9. Packaging according to claim 8, characterized in that the second passive zone (ZP2) of the receiving surface (42) of the lid (6) extends to a periphery of the lid. 44501 AP-P 19 10. Packaging according to any one of the preceding claims, characterized in that the second passive zone (ZP2) of the receiving surface (42) of the lid (6) has the form of a material recess (50) on the receiving surface (42) of the lid.
11. Packaging according to any one of claims 1 to 9, characterized in that the 5 cover (6) comprises a main cover body (6a), as well as a support device (6b) for a fastening device mounted on the cover body (6a), and in that the second passive zone (ZP2) of the receiving surface (42) is provided on the cover body (6a), and the second active zone (ZA2) of the receiving surface (42) is provided on the support device (6b), which is preferably a removable wear part. 10 12. Packaging according to any one of the preceding claims, characterized in that the fastening device (14) comprises a washer (62, 63), and in that the entire washer (62, 63) forms at least a part of the support member, and preferably the entire support member.
13. Packaging according to any one of claims 1 to 11, characterized in that the 15 fastening device (14) is a screw, or an assembly formed by a screw (14) and a washer (62, 63), and in that the bearing member is the screw head (30), or the washer (63), or an assembly formed by the screw head (30) and the washer (62).
14. Packaging according to any one of the preceding claims, characterized in that the fastening means comprise a plurality of fastening devices (14) spaced circumferentially from each other.
15. Packaging according to any one of the preceding claims, characterized in that it comprises an internal shock absorber (22), intended to protect the lid (6) and arranged inside a containment enclosure (10) for radioactive materials (12), the containment enclosure (10) being defined by the packaging body. 25 16. Package (100) comprising a package (1) according to any one of the preceding claims, and radioactive material (12) arranged in the package.