DE2019446A1 - Packaging for radioactive substances or the like. - Google Patents

Description

2019Λ46

DiPL-PHYS. WILLY LORENZ, 8035 GAUTING, HUBERTUSSTRASSE 83 '/ »· TEL. MUNICH (0811) 862524

2 April 2, 19 70

My files: r 7 6-j

ROBATEL SLPI
Lyon, Rhone (France)

Packaging for radioactive substances or the like.

The invention relates to a package or a Containers for the transport and / or the wrapping of radioactive materials or the like. , at or between the inner Container and the outer jacket a lead cladding against gamma radiation and a screen made of a neutron protective material is provided.

In the case of substances that can emit neutrons, it is known to be necessary to use the packaging in addition to the usual, for prevention Lead cladding, which is used for Gami radiation, also has a screen made of a suitable neutrophage material equip. In general, the packaging has an inner container that contains the radioactive material or the like. records and is inserted into an outer metal shell, leaving an annular space for the lead cladding, the is in turn surrounded by a layer of neutrophage material.

Such a container is perfectly suitable for the

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ti «

Transport or the wrapping of radioactive substances with low residual energy, on the other hand, containers of this type are practically unusable due to the low thermal conductivity of the neutrophagous materials commonly used ₉ when it comes to radioactive substances, which release a large amount of heat! Because of the presence of the neutrophage screen, the heat given off cannot be dissipated sufficiently through the outer jacket, so that the lead cladding can unintentionally melt »

The invention is based on the object of addressing this disadvantage eliminate and create a packaging of the type mentioned, which can also be used when radioactive substances with large residual energy are to be transported.

This object is achieved according to the invention in that the neutron protection material is in tubular elements, which consist of a metal with high thermal conductivity and are embedded in the mass of the lead cladding are"

Of course, the tubular elements mentioned must be designed in such a way that they provide a continuous shield against the passage of neutrons »For this purpose, these elements can have a suitable, corresponding cross-section have directed profile ι according to a preferred Embodiment of the invention they can be in concentric, be arranged opposite angularly displaced rows.

Preferred embodiments of the invention are described in more detail below with reference to the drawing, for example!

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show it:

Fig. 1 is a schematic longitudinal section of an according to the invention trained packaging;

Fig. 2 is a partial cross section along the line II-II of Fig. 1 on an enlarged scale;

Fig. 3 and U are partial cross-sections according to two modified ones Embodiments of the invention.

The packaging or the container according to FIGS. 1 and 2 has a cylindrical inner container 1 made of metal, which with a considerable annular space in a likewise cylindrical outer metal jacket 2 is used. The latter is closed at the bottom by a bottom 2a, while its upper edge carries a fixed cover ring 2b which is designed to be connected to the corresponding Edge of the container 1 fits together and results in a shoulder that acts as a mounting seat for a removable closure or Lid 3 for closing the container 1 is used.

A lead mass is poured into the annular space between the container 1 and the outer shell 2, which forms the lead clothing 4 against gamma rays. Inside this lead cladding there are a number of tubular elements 5 embedded, which consist of a metal with good thermal conductivity, e.g. copper; as can be seen from Fig. 2, these are Elements 5 separated from each other and arranged in a single row concentric to the axis of the container 1, you However, the profile is designed so that the entirety of these elements provides a shield against the radial passage of the

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forms neutrons coming from the radioactive material contained in the container. Each element 5 is associated with a neutrophage Material filled with its ends closed after filling will. The height of the elements 5 corresponds at least to that of the container 1; they run between two layers 7 and 8 made of a neutrophage material which is identical to or identical to the mass 6 located in the same is similar to her. It should be noted that the lead cladding 4 den between the container 1 and the outer shell 2 does not completely fill the annular space provided; while pouring this Rather, the cladding leaves an annular recess which, after the lead has cooled, is covered with a plaster of paris 9 is filled, which according to French Patent No. 1 43 8 241 of October 21, 19 64 serves as fire protection.

When the lead cladding 4 cools down, the lead pulls, whose coefficient of expansion is greater than that of copper, and thereby clamps the elements 5, creating an excellent contact between these elements and the cladding 4 is guaranteed. Under these conditions, the contained in the container becomes radioactive Substance released heat absorbed by the cladding 4 and over the elements S and the plaster layer 9 on the outer jacket 2 transferred, which releases it to the outside air. -In this way-will-excessive heating of the Lead cladding 4 is considerably restricted despite the mediocre heat transfer coefficient of the material 6. In addition still comes that the elements 5 distribute the heat over the entire height of the outer shell 2 and so the delivery of the same favor.

In the embodiment under consideration, the cover 3 has a

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Metal plate 3a, on both sides of which a lead mass 3b and a mass 3c of neutrophagous material is provided. Of course, however, the cover 3 can also be designed in the same way as described above with regard to the actual container, i.e. * the Neutron protection material can be housed in tubes, which are embedded in the lead mass and suitably arranged with respect to one another.

Of course, the tubular elements 5 can be any have any cross-section, provided that they form an effective shield. In Fig. 3, these have Elements 5 have a substantially V-shaped profile, while according to FIG. 4 two concentric, opposite to each other angled shifted rows of tubes 5 are provided with a rectangular profile.

The neutron protection materials must of course depend on the Temperatures can be selected that can occur in a packaging of a certain type for a given content. In practice, it can either be a mixture of plaster of paris and polyethylene in granular form or a neutrophage Concrete, metal hydrides or metal borohydrides, or hydrant! Sated hydroxides, etc. act.

Patent claims

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Claims (6)

Patent claims Iy packaging or container for the transport and / or the wrapping of radioactive substances or the like, in which a lead covering against the guarantee radiation and a screen made of a neutron protective material is provided between the inner container and the outer jacket marked that this material is in tubular elements (5), which consist of a metal with high thermal conductivity and are embedded in the Maas © of the lead cladding (Ό » 2. Packaging according to claim I _9, characterized in that the tubular elements (5) dm cross-section are shaped in such a way ₉ that they form a continuous shield against the radial passage of neutrons from the inner container « 3. Packaging according to claim I _9, characterized in that the tubular elements (5) are arranged in at least two concentric rows that are angularly displaced from one another » 4. Packaging according to one or more of the preceding Claims, characterized in that the tubular elements (5) extend at a height that is at least that of the inner container (1) corresponds. 5. Packaging according to one or more of the preceding Claims, characterized in that between the lead lining (Ό and the outer jacket (2) an annular 209808/0141 A space is provided which receives an insulating compound (9) for fire protection purposes. 6. Packaging according to one or more of the preceding claims, characterized in that both sides of the transverse ends of the lead compound (MO two layers (7, 8) of neutrophagous material are provided. 209808 / 0U1 Lee r side