FR2902090A1 - Parallelepiped shaped container e.g. box, for storing e.g. syringe, has closing device or cover, and double skin integrated on upper part of walls, where container is made of flexible sheath type sealing plastic material e.g. polyethylene - Google Patents

Abstract

The container (1) has a closing device or cover (4), and a double skin integrated on an inner upper part of lateral walls (2), where the container is made of flexible sheath type sealing plastic material e.g. polyethylene. A fixed handle co-operates with a physical unit that is constituted by orifices on the lateral walls. The double skin is presented by a passageway constituted of bridgings, where the bridgings are made of plastic material, and vertical grooves are provided on a base (3).

Description

DEVICE CAPABLE OF CONTAINING VERY LOW ACTIVE ACTIVE NUCLEAR WASTE

  The present invention belongs to the fields of handling, storage, transportation and storage of nuclear waste. More specifically, the invention relates to a device capable of containing very weakly active waste.

  For certain industrial sectors such as defense, space and nuclear, specific containers are made. The latter provide certain mechanical, climatic, physicochemical and thermal guarantees for the storage, handling and transport of complex radioactive products, such as gloves, gowns, syringes, filters, rags, concrete, rubble, scrap metal. from the production of civil or military nuclear energy, the medical field, conventional industry or past applications of radioactive material that can not be reused or reprocessed.

  In particular, for example, the nuclear sector needs specific containers and tools for the safe handling, transport and storage of new, irradiated fuel and low-level (LF) and very low-level (LLW) waste. .

  Each type of waste requires different management. They are classified according to two criteria: the intensity of the radioactivity which conditions the dangerousness of the products and the radioactive period of the contained products which defines the duration of potential nuisance. Thus, it is estimated that it is about three hundred years for short-lived waste. These are coated in various materials (cement, bitumen or resin), and stored in surface drums in barrels, metal boxes or concrete shells, arranged in cells dug in clay.

  It is therefore essential to be able to effectively manage and maintain equipment dedicated to nuclear activities, to transport new fuels from suppliers to consumer sites and to transport waste from nuclear sites to storage sites.

  Currently, TFA waste is packaged in packagings, such as, for example, containers, drums ... essentially metallic. These types of known containers are, of course, good mechanical strength and manipulable without special radiation protection provision but have the disadvantage of being heavy and therefore difficult to manipulate. Indeed, even empty, these containers are require the use of rudder, specific slings or forklift. In addition, the storage of this type of packaging must be carried out indoors or outdoors under cover, in order to avoid any corrosion phenomenon.

  It is known from European Patent Application No. EP1557251, a method of manufacturing a double-walled container by rotational molding. There is disclosed a method of producing a double walled plastic container with external ribs. Rotational molding is a process analogous to rotational casting, in which dry, finely divided and fusible powders are distributed against the mold wall and brought to the melting state. This technique allows the production of a wide variety of hollow items. The mass of this type of known container, comprising a double wall, is certainly less important than a metal container but could be improved. In addition, this kind of device, consisting of two half-shells, can not be handled simply and does not allow stacking.

  The present invention overcomes the disadvantages of the prior art by providing a device for obtaining a lightweight and convenient container to handle.

  In addition, it contains ergonomic means for any movement thereof without encumbering the useful volume of the container. In addition, the device according to the invention makes it possible to reduce their mass while ensuring a good rigidity and a possible stacking. In addition, this device according to the invention, via the use of a lid, has improved sealing properties under external conditions. Indeed, this device is completely waterproof and weatherproof but also to the environment or environment of their use, such as physical or chemical constraints.

  In addition, the device according to the invention allows a simplification of the manufacturing process.

  Advantageously, the device according to the invention also makes stacking easy and stable.

  To this end, the device according to the invention, formed of a plastic container, consisting of walls and a bottom, is characterized in that a reinforcing means is integrated on at least a portion of its walls.

  More specifically, said reinforcing means consists of a double skin which is an integral part of the walls and is provided by a tunnel consisting of plastic bridges. It is thus fused on the inner upper part of the walls of the container.

  Advantageously, the device according to the invention is manufactured in a single step, by rotational molding, to simultaneously obtain said integrated reinforcement means and housing means gripping.

  More specifically, the upper part of at least two walls containing the integrated reinforcement means comprises physical means able to receive said gripping means.

  Said gripping means are in the form of fixed handles capable of cooperating with said physical means constituted by is orifices on at least two of the walls.

  Alternatively, the device according to the invention comprises a closure device.

  More specifically, the gripping means and the spatial configuration of the container with or without a lid allow it to be handled and stacked.

  Preferably, the device according to the invention is able to contain and / or protect low-level radioactive products.

  The invention will be better understood in the light of the description which follows, referring to illustrative and in no way limiting examples of the present invention, with reference to the attached drawings, in which: FIG. schematically the device according to the invention; Figure 2 is a perspective view from above of the container of the device according to the invention; FIGS. 3, 4 and 5 are respectively perspective views of the sides, top and bottom of the device according to the invention; FIG. 6 is a partial sectional view of the upper part of the mold forming the device according to the invention; Figure 7 shows the lid of the device according to the invention; Figure 8 is a perspective view of the container of the device according to the invention Figures 9 and 10 illustrate schematically and partially gripping means of the device according to the invention. The principle of the invention is to be able to manufacture a container in one piece, of a desired shape; easy to handle for transport and / or storage.

  Preferably, the monoblock container is capable of containing TFA products.

  Figure 1 illustrates the entire device according to the invention.

  The device according to the invention consists of a container 1 of generally parallelepipedal shape which has four side walls 2 and a bottom 3.

  Alternatively, the container 1 may take any other form able to contain and protect a product during its handling, transportation, storage, place of manufacture, use or storage. The container 1 may be, for example, a box, a box, a container of generally parallelepipedal shape adapted to be provided with a closing device or cover 4. The container 1 is made of a light material, resistant to corrosion and impervious to external climatic conditions, such as, for example, polyethylene or any other plastic material. This material makes it possible, in fact, a considerable gain in mass but also the possibility of storing the device according to the invention on the outside without the need for a shelter.

  Gripping means 5 are directly integrated into the device according to the invention. More specifically, Figure 2 illustrates in perspective the container of the device according to the invention, without cover.

  The gripping means 5 are integrated into the container after rotational molding by screwing or by any other fastening means of known type. These gripping means 5 conform to handles that are located in the volume defined by the walls 2 of the container 1. In other words, they are not offset on the outside of the container thus allowing to be located in the extending the walls 2 of the container 1 and increase the volume of the container 1 and their mechanical strength.

  Advantageously, these handles 5 are resistant to handling the container 1 loaded, using specific slings, forklift or lifter.

  In addition, the structural design of these handles 5 avoids the need to make corresponding complementary parts on the bottoms 3 of the containers 1 in order to effect a stable stacking of the latter.

  Figures 3, 4 and 5 are respectively side views, top and bottom perspective of the device according to the invention.

  w The walls 2 and the bottom 3 of the container 1 have grooves 6. In fact, the rigidity of the container 1 is ensured by a series of vertical grooves 6 on the lower part of the four walls 2. They cover about 80% of the the height of the container 1.

  grooves 7 are provided on the bottom 3 of the container 1 to increase its rigidity and ensure the stability of the stacking of several containers 1.

  This specific shape of the container 1 and these grooves 6, 7 are obtained by means of the shape of a mold and by means of female tools, such as, for example, tools cast and machined aluminum.

  The grooves 6, 7 are obtained by rotomolding thanks to a single mold. They serve as mechanical reinforcement and their widths are calculated according to the dimensions of the desired container 1.

  There is therefore provided a single mold for the container 1 comprising the necessary tools to obtain the grooves 6 and 7 and the housing of the handles 5. The rigidity and mechanical strength of the upper part of the walls 2 are provided by a means reinforcement 8 or more precisely by a double skin type structure (shown in Figures 6 and 8). This double skin 8 is located on at least a portion of the walls 2 of the s containing 1.

  Preferably, the double skin is fused to the inner upper part of the walls 2 of the container 1 and represents approximately 18% of the height of the latter. This double skin 8 is provided by a tunnel consisting of plastic bridges thus allowing rigidity necessary for lifting the container 1 by the handles 5 by lifting forks, for example.

  FIG. 6 is a view in partial section of the upper part of the mold forming the device according to the invention and of the upper part of the walls consisting of the double skin

  The double skin 8 is formed by the deposition of the molten powder on the inner part of the mold consisting of an upper closure tool 9 and a lower tool 10 (air gap cover), during rotational molding.

  More precisely, by "double skin" 8 we mean the phenomenon generated by two layers of material which have been bonded with or without interstices 11. It is obtained by the use of a second tool which allows the circulation of the polyethylene powder. for example, inside and at the same time bridging two skins, one inside with the other outer skin. This bridging is obtained by progressive approximation, until contact with the outer skin and the inner skin as the deposition of the material in the liquid phase and is not comparable to a double wall.

  The double skin 8 is formed by the unfilled space and can be filled with material if the space between the two mold parts is very close to each other or if the amount of material is calculated accordingly. Depending on the desired density and the mold surface, the amount of powder is calculated to obtain the desired thickness. The double skin is thus also obtained in a single step. Alternatively, it may be provided to add retractable legs or pads 12 for handling the container 1 with a pallet truck or forklift, for example. These pads 12 are fixed by means of fasteners of a type known per se. Without pad, the container 1 pt.Jt 15 be placed directly on the ground.

  Advantageously, provision is made for the inserts for fixing the pads 12 during the rotational molding steps.

  Figure 7 shows the lid of the device according to the invention.

  The lid 4 is made of a waterproof material of flexible type of parallelepipedal general shape adapted to the container 1. It is equipped with bungee cord 13, eyelets 14 and hooks 15 to maintain and 25 to give it flexibility necessary in stacking configuration.

  The device according to the invention consists of inserts, of a type known per se, embedded in the material and set back with respect to the external profile. These allow without any drilling operation to fix the holding means 13, 14 and 15 of the cover 4, for example by lo riveting, to contant 1 ensuring, thus, a perfect seal of the device.

  Figure 8 is a perspective view of the container of the device according to the invention.

  This figure illustrates the container 1 comprising its grooves 6, 7, its pads 12 and its locations or housing handles 5. In order to place the handle 5, there is provided a small notch 16 and a large io notch 17 on the upper part d At least two walls 2. The large notch 17 allows the positioning of the handle 5 and gripping it. For a notch 17, there are two notches 16 for fixing a handle 5 at its ends.

  Figures 9 and 10 schematically and partially illustrate the gripping means of the device according to the invention.

  The handles 5 are fixed and consist of a longitudinal rod 18 inserted at a notch 17 for the passage of a hand or a lifting tool. The notches 16 and 17 of the integrated handles 5 are obtained by a suitable form of male tools during rotomolding, thus leading to a higher resistance to the mechanical strength of the handles 5.

  The gripping means 5 are able to cooperate with physical means 19.

  The physical means 19 consist of orifices conforming to a longitudinal opening. They are provided on at least two of the walls 2 of the container 1 and are able to cooperate with the rod 18. They are obtained by the application of metal inserts during rotational molding, for example, of high conductivity beryllium copper inserts. thermal. The rod 18 is, for example, made of steel.

  Alternatively, it can also be made of any other material having a high lifting performance.

  Its implementation is carried out manually in the location 17 provided for this purpose. It is then mounted and fixed at its two ends in the location 16 to the mounting means 20 of the type known per se.

  Preferably the fastening means 20 are nuts and washers. The manufacturing method of implementation can be achieved, for example, by rotational molding. This makes it possible to obtain in a single step the container comprising a double skin 8 and grooves 6, 7 as well as the integration of the slots or notches 16, 17 of the handles 5. The rotomolding technique makes it possible to obtain hollow body with a constant thickness of polyethylene, for example.

  Alternatively, any other equivalent material, such as polyamide, PVC, etc. may be used.

  The rotomolding steps carried out for the production of the container according to the invention consist of the steps: preparation of a mold with the pre-positioning of retractable metal inserts after rotational molding (for the handles, for example) and metal inserts of fastening (eg hooks and pads); filling the mold with a filler, for example, polyethylene powder; s closing of the upper part of the mold; rotation of the mold along two orthogonal axes; entering the mold into the furnace (at a temperature higher than that of melting the polymer used); temperature rotation in the oven; Transfer, in rotation, of the mold to the cooling station so that the polymer solidifies before demolding the part.

  The part then undergoes the finishing steps, such as deburring, installation of accessories, etc. During the rotation, the plastic material which has previously been presented in the rotary mold is distributed evenly over the inner surface of the rotary mold. . The rotational mold is also heated during this operation, such that the plastics material is uniformly distributed. The formed plastic is then cooled before opening the mold.

  The double skin 8 is formed when the polyethylene melts and lodges in the space left between the lid and the lower mold. The initial amount of polyethylene powder is such that ultimately the desired thickness is obtained and also the bridging between the two skins face to face.

  The ergonomics of the handles 5 and the relatively small mass due to its constitution allow the empty container 1 to be handled by two persons.

  The invention lies mainly in the choice of the material and its manufacturing process resulting in a simplification of its production and a lightweight package containing reinforcing means 8 and integrated handles 5 thus facilitating its handling. The device according to the invention can have several types of application such as conventional industrial transport, the burial of radioactive waste TFA and the collection of special waste.

  Advantageously, this container 1 having a double skin, grooves 6, 7 and a certain spatial configuration (with or without lid) is thus adapted to the large format for very weakly active waste containers, facilitating handling and / or storage by gripping means included in the useful volume while keeping a good mechanical strength.

  Thus it is possible to effectively manage and maintain equipment dedicated to nuclear activities, transporting waste from nuclear sites to storage or storage sites. 20 20 25

Claims (10)

  1. Device, forming a container (1) made of plastic, consisting of walls (2) and a bottom (3), characterized in that a reinforcing means (8) is integrated on at least a part of its walls (2)   2. Device according to claim 1, characterized in that the reinforcing means (8) consists of a double skin integral with the walls (2).   3. Device according to one of claims 1 or 2, characterized in that the double skin (8) is presented by a tunnel consisting of 15 plastic bridges.   4. Device according to one of claims 2 or 3, characterized in that the double skin (8) is fused to the inner upper part of the walls (2) of the container (1).   5. Device according to one of the preceding claims, characterized in that it is manufactured in a single step by rotational molding to obtain simultaneously the integrated reinforcement means (8) and housing (16, 17) of the gripping means (5).   6. Device according to one of the preceding claims, characterized in that the upper part of at least two walls (2) containing the integrated reinforcing means (8) comprises physical means (19) adapted to receive the gripping means (5). 30   7. Device according to claim 6, characterized in that the gripping means (5) are in the form of fixed handles adapted to cooperate with said physical means (19) constituted by orifices on at least two of the walls (2). . s   8. Device according to one of the preceding claims, characterized in that it comprises a closure device (4).   9. Device according to one of the preceding claims, characterized in that its gripping means (5) and the spatial configuration of the container (1) with or without cover (4) allow its handling and stacking.   10. Device according to one of the preceding claims, characterized in that it is able to contain and / or protect low-level radioactive products.