Patent ID: 7741628

Claim:
A method for manufacturing a long-term storage container for storage of radioactive material to inhibit radioactive radiation therefrom to the outside of the container, said container having a bottom and upright wall extending therefrom, the top of said container to be closed off by a screw-on lid, said container having an integral inner container part of a first material with a bottom and upright wall, an integral outer container part of a second material with a bottom and upright wall, and radioactive radiation inhibiting material in an inter-space between the walls and bottoms of said inner and outer container parts; the method comprising: integrally casting in a first mould through injection moulding a first container part having a bottom and a wall, removing the first container part from the first mould; integrally casting in a second and separately located mould through injection or pressure moulding an inter-space container part of said radioactive radiation inhibiting material, said inter-space container part having a bottom and a wall and forming a second container part, removing said interspace container part from the second mould, placing the first container part in a third mould, placing said inter-space container in fitting engagement with exterior face of the first container part to form a first assembly of container parts, in the third mould locating the first assembly of container parts to cause said inter-space container part to be in spaced relationship to a mould member of the third mould, so as to form a cavity between the mould member of the third mould and the outside of the inter-space container part, the inside of the first container part being fitted onto a core member of the third mould, through injection moulding into said cavity integrally casting the outer container part forming a third container part having a side wall and a bottom, said third container part engaging the exterior faces of the inter-space container part, and removing from the third mould a second assembly of container parts formed by the first, second and third container parts to provide said storage container.