Improving Facility Operations and MC&A with Canberra’s OSPREY

Advanced Test Reactor (ATR) fuel elements are assayed for U-235 content upon receipt of the material from Babcock & Wilcox Technologies, Inc. (BWXT). Idaho National Laboratory Safeguards personnel perform receipt verification measurements on the ATR fuel with a Vertical Fuel Scanner (VFS). The VFS utilizes a low resolution gamma-ray detector, computer, two motors, an analog control panel and an apparatus that holds and rotates the fuel element while the detector traverses the element and collects spectroscopy data. This spectral data is then used to quantify the amount of U-235 present in the entire element. This unique measurement system produces a quantitative measurement with a precision and accuracy of ~5%, sufficient to detect substitution of one fuel plate in an element, making it one of the highest quality nondestructive assay techniques at the INL. Upgrades of the control mechanism responsible for moving the element and the detector were completed in 2013 utilizing a “smart” servo motor, custom power supply, and custom instrument control software (ICS). This critical upgrade allowed for the continued operation of a high quality measurement system. The second portion of the upgrade replaced the older NaI detector with a temperature stabilized OSPREY NaI detector from Canberra and integrated data acquisition and control with the ICS using Canberra’s Genie 2000 programming libraries. These programming libraries were integrated into the ICS using LabVIEW. This integration facilitated the embedding and automation of Genie 2000 Data Acquisition and Analysis functions including control, acquisition, display, analysis, reporting, and file manipulation algorithms. Integrating the data acquisition system into the ICS simplified the operation of the instrument, improved random uncertainty, and implementation of the OSPREY virtually eliminated the warm up time and run time drift observed before the upgrade. Prior to the upgrade, 2-3 days were required to complete a measurement evolution on a single receipt. Post upgrade measurements could be completed in a single day if not for facility operational constraints.