Tube for storage in pool of irradiated nuclear fuels - incorporates base adjustable in height allowing for differences in height of fuel elements

摘要

A storage tube with a base adjustable in height partic. for storage in a pool of irradiated nuclear fuels comprises walls each having a vertical alignment of support elements each able to accept a support on the wall from inside the tube, a base adjustable in height in the tube and a central control component. The base has retractable lateral projections which are disposed each opposite one of the support elements and which can take two positions, an outward position in which the retractable extensions interfere with the support elements to allow the supporting of the base on these elements and an inward position which allows the base to be displaced in height without interference with the support elements. The rotation of the control component brings about the movement into the two positions. The base comprises an upper body and a lower body, means of mutual guiding to prevent the relative rotation of the two bodies while allowing their relative displacement parallel to the axis, a screw parallel to the axis and connecting the two bodies so that its rotation controls the relative displacement, this screw constituting the central control component, and upper and lower connecting rods. The connecting rods are fitted with articulation axes perpendicular to the axis of the tube and connect respectively the upper and lower bodies to the retractable projections. The angles made by the upper connecting rods with the axis of the tube are in opposite senses to those made by the lower connecting rods so that the relative displacement of the two bodies parallel to the axis brings about a radial displacement of the retractable projections. The mechanism of putting the base in support utilises rotation without friction or gearing. It is impossible for powders to accumulate on the mechanisms. Control is by a manoeuvring rod. The mechanism is simple and the cost of construction is low.