|
Exterior view of ZPR-3 |
Zero Power Critical Reactor No. 3 (ZPR-3) was operated for the Atomic Energy Commission (AEC) by ANL-W. The facility provided a remote method for using mock-ups to determine the accuracy of geometries of a critical mass assembly. It was used to determine critical measurements in connection with various loading for make-up of fast reactor core designs. Experimental critical assembly results in this field were almost completely lacking before the advent of the ZPR-3 facility in October 1955.
The critical assembly machine is basically a platform on which two tables or carriages are mounted, one of which is movable. Half of the assembly is built up on each carriage by means of a matrix structure. The movable carriage allows the assembly to be split in half, both as a safety measure and for convenience in loading. Criticality is achieved when the two halves are brought together and the control rods suitably positioned.
Two halves of the ZPR-3 cricical assembly |
Each half of the assembly contains five safety control rods of the fuel removal type. Four rods in each half function as safety rods, the fifth is used as a control rod. Trays are filled with fissionable material and other metals to permit the simulation of various reactor types and configurations.
ZPR-3's mission was taken over by ZPPR after it's construction was finished. ZPPR was a more modern, more flexible facility. The ZPR-3 core is currently avaliable for public view at the EBR-I site.