Patent Number: 
Section: description

As seen in the drawing a transport and/or storage container for spent fuel elements has a cover 1, a floor 2, a cylindrical side wall 3 and an interior 4 centered on a normally upright axis 18. The side wall 3 comprises an inner side wall 5 bounding the container interior 4 and an outer side wall 6 offset outward from the inner side wall 3. A space 7 between the inner side wall 5 and the outer side wall 6 is filled with heavy concrete shown partially at 20 in FIG. 3. According to the invention the inner side wall 5 is connected to the outer side wall 6 by heat-dissipating sheetmetal elements 8. One edge of each metal sheet 8 is firmly connected to the inner side wall 5 by welding. As shown particularly in FIG. 3, reinforcing elements in the form of U-profiles 9, 10 are fastened to the outer surface of the inner side wall 5 and to the inner surface of the outer side wall 6. The edges of the metal sheets 8 are connected to the U-profile 9 fastened to the inner side wall 5 by welding to an arm 11 of the U-profile 9. The other edge of each of the metal sheet 8, on the other hand, abuts a respective arm 12 of the outer side wall 6 under prestress, thus forming a heat-conducting contact. In this manner heat is conducted between the inner side wall 5 and outer side wall 6. The metal sheets 8 are uniformly distributed over the entire periphery of the container between the inner side wall 5 and the outer side wall 6. The U-profiles 9, 10 extend over the entire height of the container, i.e. from the cover 1 to the floor 2 and they are angularly uniformly spaced, with the outer profiles 10 being of course spaced somewhat more widely than the inner profiles 9 so that they strengthen and reinforce the walls 5 and 6. As shown in FIG. 3, the metal sheets 8 connected to the U-profiles 9, 10 form trapezoidal spaces seen in plan view for receiving the filler, usually concrete. If, advantageously and as in the exemplified embodiment, two adjoining metal sheets 8 are welded to the same U-profile 9 on the inner side wall 5, the metal sheets 8 abut different neighboring U-profiles 10 on the outer side wall 6. The surface of a metal sheet 8 is aligned at a right angle to the container floor 2 and to the container cover 1. According to the invention the metal sheets 8 are provided throughout from the cover 1 to the floor 2 in the annular space 7. Consequently the height of the preferred metal sheets 8 is substantially equal to the height of the container, particularly the height of the inner side wall 5. Rectangular portions or tabs 13 are bent at an angle from the metal sheets, bent out like awnings or windows. FIG. 3 shows how a plurality of pairs of bent metal-sheet portions 13 are disposed one above the other in a metal sheet 8. Each pair of bent metal-sheet portions 13 is disposed at the same height on the metal sheet 8. In the embodiment the two metal-sheet portions 13 of each pair are bent in opposite directions from the plane of the respective sheet 8, through an angle xcex1 of 22xc2x0 to 24xc2x0 away from the metal sheet 8. The height h of a bent metal-sheet portion or window 13 is 50 mm, whereas the overall width w of one of the sheets 8 is 125 mm. The height hxe2x80x2 of webs 19 between superposed bent metal-sheet portions 13 is 40 mm. The metal sheets 8 and the bent portions 13 have a thickness of 2 mm. The container floor 2 comprises an inner floor wall 14 and an outer floor wall 15 and heat-dissipating metal sheets 17 are likewise provided in a space 16 between the inner floor wall 14 and outer floor wall 15 (see FIG. 5). The inner floor wall 14 is connected to the inner side wall 5 and the outer floor wall 15 is connected to the outer side wall 6. The metal sheets 17 are firmly connected to the inner floor wall 14, preferably by welding, and they abut the outer floor wall, forming a heat-conducting contact. As shown in FIG. 5, two rows of metal sheets 17 are disposed concentrically around the central axis 18. Both the space 16 between the inner floor wall 14 and the outer floor wall 15 and the space 7 between the inner side wall 5 and the outer side wall 6 are filled with heavy concrete.