LATEST DEVELOPMENT AND IMPLEMENTATIONS OF INSTRUMENTS FOR URANIUM ASSAY BY DELAYED NEUTRON TECHNIQUES
Two devices: SIGMA and DUCA have been studied and developed in the last years at JRC Ispra. These instruments contain an irradiation zone and a counting zone; for SIGMA some improvements were made: All operations at floor level; automatic measurement repetition; solid state devices for increased reliability; computing of corrected mean values. A very fast neutron counting chain reduces counting loss at start of measurement; dead time is about 1 us. The control and data handling system consists of: microcomputer (SIGMA: u MAC 5000 Analog Device - DUCA: Intel 8030) plus dedicated software and linked, intelligent terminal (IRIS); neutron counting chair; synoptic panel; and low voltage power supplier unit. Laboratory tests, field tests and implementation exercises have been made in all, the system can be said to: give minimum verification time, require minimum inspector effort; provide automatic self diagnosis: contain new designs for maximum reproducibility, and improved measurement accuracy. The devices have two fields of application: SIGMA, stationary at HOBEG, has been dedicated to inspections on pebbles of AVR and THTR reactors (verification of powder and pellets using dummy pebbles as sample holders); DUCA, transportable, will be used for inspections on powder or pellets of Light Water Reactor with a sampling on bulk quantity.
Bibliographic Reference: INTERNATIONAL SYMPOSIUM OF NUCLEAR MATERIAL SAFEGURADS, WIEN (AUSTRIA), NOV. 10-14, 1986 WRITE TO CEC LUXEMBOURG, DG XIII/A2, POB 1907 MENTIONING PAPER E 32688 ORA
Availability: Can be ordered online
Record Number: 1989125020000 / Last updated on: 1987-02-01
Available languages: en