Patent Number: 
Section: claims

1. A container for holding radioactive waste, the container comprising:a side wall;a floor connected to a lower end of the side wall;a cover;a set of side-wall formations at an upper end of the side wall and on an inner surface of the side wall; anda set of cover-edge formations distributed around an outer edge of the cover and fittable with the side-wall formations such that, as a result of the interfitting of cover-edge formations with the side-wall formations, the formations of one of the sets being L-shaped radially open grooves that each have two portions extending perpendicular or substantially perpendicular to one another such that the cover can be or is fixedly connected to the side wall without welds. 2. The container defined in claim 1, further comprising:a support basket inside the container for holding spent fuel elements constituting the radioactive waste. 3. The container defined in claim 1, wherein the floor and the side wall are integrally connected to one another. 4. The container defined in claim 1, wherein there are at least three of the side-wall formations distributed around the inner surface of the side wall. 5. The container defined in claim 1, wherein there are at least three cover-edge formations distributed around the outer edge of the cover. 6. The container defined in claim 1, wherein the formations of the other of the sets are radial projections fittable in the grooves. 7. The container defined in claim 1, wherein the side wall is substantially cylindrical and centered on an axis, one of the portions of each groove extending tangentially and the other of the portions of each groove extending axially. 8. The container defined in claim 7, wherein, in a locking position with the cover axially secured by the formations to the side wall, the formations of the other set each bear upward on a downwardly directed upper face of the one portion of the respective groove. 9. The container defined in claim 8, wherein an upwardly directed lower face of each of the other portions of each groove is angled downward and toward the floor, and lower downwardly directed faces of the formations of the other set are complementarily angled, whereby an upward force on the cover pulls the upper edge of the side wall radially inward. 10. The container defined in claim 1, wherein the cover and side wall form an upwardly open sealing groove, the container further comprising:an annular seal fitted in the groove. 11. The container defined in claim 10, wherein the seal is a metal or elastomeric seal. 12. The container defined in claim 10, further comprising:a compression ring releasably secured atop the cover and formed with an axially downwardly projecting ridge engaging in the groove and pressing the seal against an upper face of the sealing groove and the inner surface of the side wall. 13. The container defined in claim 12, wherein the ridge has a frustoconical lower face facing radially outward and downward and the sealing groove has a frustoconical upper face facing radially outward and upward, whereby the ridge presses the seal radially outward against the inner surface of the side wall when axially squeezing the seal between the lower and upper faces. 14. The container defined in claim 1, wherein the container is a transport or storage container, the cover is a primary cover of the transport or storage container, the container further comprising:a secondary cover fixed to the container above the primary cover seals. 15. A container assembly, comprising a container according to claim 14, wherein the container is a canister loaded with spent fuel elements and received in a transport or storage container that can be or is sealed with the secondary cover over the primary cover.