REMOTE-CONTROLLED NDA SYSTEMS FOR PROCESS AREAS IN A MOX FACILITY

Year
1989
Author(s)
R. Abedin-Zadeh - International Atomic Energy Agency
Ronald Augustson - Los Alamos National Laboratory
M.C. Miller - Los Alamos National Laboratory
T. Ohtani - Power Reactor and Nuclear Fuel Development Corporation
S. Takahashi - Power Reactor and Nuclear Fuel Development Corporation
H.O. Menlove - Los Alamos National Laboratory
M. Seya - Power Reactor and Nuclear Fuel Development Corporation
Abstract
Nondestructive assay (NDA) systems have been designed and installed in the process area of an automated mixed-oxide (MOX) fuel fabrication facility. These instruments employ neutron coincidence counting methods to measure the spontaneous-fission rate of plutonium in the powders, pellets, and fuel pins in the process area. The spontaneous fission rate and the plutonium isotopic ratios determine the mass of plutonium in the sample. Measurements can be either attended or unattended. The fuel-pin assay system (FPAS) resides above the robotic conveyor system and measures the plutonium content in fuel-pin trays containing up to 24 pins (~1 kg of plutonium). The material accountancy glove-box (MAGB) counters consist of two slab detectors mounted on the sides of the glove box to measure samples of powder or pellets as they are brought to the load cell. Samples measured by the MAGB counters may contain up to 18 kg of MOX. This paper describes the design and performance of four systems: the fuel-pin assay system and three separate MAGB systems. The paper also discusses the role of Monte Carlo transport techniques in the detector design and subsequent instrument calibration.