Patent Number: 052873919
Section: summary

BACKGROUND OF THE INVENTION This invention relates to a metering system, and more particularly, for a metering system for controlling the feed of portions of nuclear fuel assemblies. After reprocessing in a chemical plant where the nuclear material (e.g. UO.sub.2) in the nuclear fuel assemblies is dissolved in a solvent stream, residues of the assemblies need to be encapsulated in a cementitious matrix in standard storage containers or drums. These residues chiefly comprise appendages of the nuclear fuel assemblies and hulls which are small sheared tubular portions of cladding tubes which contained the nuclear material. In order to provide a high utilisation of the space within the drum, it is advisable to regulate the ratio of appendages to hulls fed to the drum. SUMMARY OF THE INVENTION According to the present invention there is provided a system for metering the feed of portions of nuclear fuel assemblies, the system comprising a declivitous screen for receiving the portions and for separating the portions into larger and smaller components thereof, a first receptacle for collecting the larger components falling from the screen and for discharging the larger components into a collecting receptacle, the collecting receptacle being controllable so as to discharge the larger components therein on to means for directing the larger components into a container, means for sensing the level of the portions in the container, a buffer chamber for receiving the smaller components passing through the screen, a discharge port of the buffer chamber for discharging the smaller components from the buffer chamber into an oscillatable trough adapted to oscillate around the longitudinal axis thereof to discharge a metered quantity of the smaller components therefrom, and means for receiving the smaller components discharged from the trough and for feeding said smaller components to the container. The invention will now be further described by way of example only with reference to the accompanying drawings, in which: