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Title: Gamma densitometer for measuring Pu density in fuel tubes

Abstract

A fuel-gamma-densitometer (FGD) has been developed to examine nondestructively the uniformity of plutonium in aluminum-clad fuel tubes at the Savannah River Plant (SRP). The monitoring technique is ..gamma..-ray spectroscopy with a lead-collimated Ge(Li) detector. Plutonium density is correlated with the measured intensity of the 208 keV ..gamma..-ray from /sup 237/U (7d) of the /sup 241/Pu (15y) decay chain. The FGD measures the plutonium density within 0.125- or 0.25-inch-diameter areas of the 0.133- to 0.183-inch-thick tube walls. Each measurement yields a density ratio that relates the plutonium density of the measured area to the plutonium density in normal regions of the tube. The technique was used to appraise a series of fuel tubes to be irradated in an SRP reactor. High-density plutonium areas were initially identified by x-ray methods and then examined quantitatively with the FGD. The FGD reliably tested fuel tubes and yielded density ratios over a range of 0.0 to 2.5. FGD measurements examined (1) nonuniform plutonium densities or hot spots, (2) uniform high-density patches, and (3) plutonium density distribution in thin cladding regions. Measurements for tubes with known plutonium density agreed with predictions to within 2%. Attenuation measurements of the 208-keV ..gamma..-ray passage through the tube walls agreedmore » to within 2 to 3% of calculated predictions. Collimator leakage measurements agreed with model calculations that predicted less than a 1.5% effect on plutonium density ratios. Finally, FGD measurements correlated well with x-ray transmission and fluoroscopic measurements. The data analysis for density ratios involved a small correction of about 10% for ..gamma..-shielding within the fuel tube. For hot spot examinations, limited information for this correction dictated a density ratio uncertainty of 3 to 5%.« less

Authors:
Publication Date:
Research Org.:
Du Pont de Nemours (E.I.) and Co., Aiken, SC (USA). Savannah River Lab.
OSTI Identifier:
5184141
Report Number(s):
DP-1599
ON: DE82014894; TRN: 82-013841
DOE Contract Number:  
AC09-76SR00001
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; DENSITOMETERS; GAMMA SPECTROMETERS; FUEL RODS; HOT SPOTS; NONDESTRUCTIVE TESTING; SPECIAL PRODUCTION REACTORS; ACCURACY; ATTENUATION; COLLIMATORS; FLUOROSCOPY; LEAKS; LI-DRIFTED GE DETECTORS; PERFORMANCE TESTING; PHOTON TRANSMISSION SCANNING; PLUTONIUM 241; PLUTONIUM DIOXIDE; SAVANNAH RIVER PLANT; URANIUM 237; ACTINIDE COMPOUNDS; ACTINIDE ISOTOPES; ACTINIDE NUCLEI; ALPHA DECAY RADIOISOTOPES; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BIOMEDICAL RADIOGRAPHY; CHALCOGENIDES; DAYS LIVING RADIOISOTOPES; DIAGNOSTIC TECHNIQUES; EVEN-ODD NUCLEI; FUEL ELEMENTS; GE SEMICONDUCTOR DETECTORS; HEAVY NUCLEI; ISOTOPES; LI-DRIFTED DETECTORS; MATERIALS TESTING; MEASURING INSTRUMENTS; MEDICINE; NATIONAL ORGANIZATIONS; NUCLEAR MEDICINE; NUCLEI; OXIDES; OXYGEN COMPOUNDS; PHOTOMETERS; PLUTONIUM COMPOUNDS; PLUTONIUM ISOTOPES; PLUTONIUM OXIDES; PRODUCTION REACTORS; RADIATION DETECTORS; RADIOISOTOPES; RADIOLOGY; REACTOR COMPONENTS; REACTORS; SEMICONDUCTOR DETECTORS; SPECTROMETERS; TESTING; TRANSURANIUM COMPOUNDS; URANIUM ISOTOPES; US AEC; US DOE; US ERDA; US ORGANIZATIONS; YEARS LIVING RADIOISOTOPES; 440103* - Radiation Instrumentation- Nuclear Spectroscopic Instrumentation; 220700 - Nuclear Reactor Technology- Plutonium & Isotope Production Reactors

Citation Formats

Winn, W.G. Gamma densitometer for measuring Pu density in fuel tubes. United States: N. p., 1982. Web. doi:10.2172/5184141.
Winn, W.G. Gamma densitometer for measuring Pu density in fuel tubes. United States. doi:10.2172/5184141.
Winn, W.G. Fri . "Gamma densitometer for measuring Pu density in fuel tubes". United States. doi:10.2172/5184141. https://www.osti.gov/servlets/purl/5184141.
@article{osti_5184141,
title = {Gamma densitometer for measuring Pu density in fuel tubes},
author = {Winn, W.G.},
abstractNote = {A fuel-gamma-densitometer (FGD) has been developed to examine nondestructively the uniformity of plutonium in aluminum-clad fuel tubes at the Savannah River Plant (SRP). The monitoring technique is ..gamma..-ray spectroscopy with a lead-collimated Ge(Li) detector. Plutonium density is correlated with the measured intensity of the 208 keV ..gamma..-ray from /sup 237/U (7d) of the /sup 241/Pu (15y) decay chain. The FGD measures the plutonium density within 0.125- or 0.25-inch-diameter areas of the 0.133- to 0.183-inch-thick tube walls. Each measurement yields a density ratio that relates the plutonium density of the measured area to the plutonium density in normal regions of the tube. The technique was used to appraise a series of fuel tubes to be irradated in an SRP reactor. High-density plutonium areas were initially identified by x-ray methods and then examined quantitatively with the FGD. The FGD reliably tested fuel tubes and yielded density ratios over a range of 0.0 to 2.5. FGD measurements examined (1) nonuniform plutonium densities or hot spots, (2) uniform high-density patches, and (3) plutonium density distribution in thin cladding regions. Measurements for tubes with known plutonium density agreed with predictions to within 2%. Attenuation measurements of the 208-keV ..gamma..-ray passage through the tube walls agreed to within 2 to 3% of calculated predictions. Collimator leakage measurements agreed with model calculations that predicted less than a 1.5% effect on plutonium density ratios. Finally, FGD measurements correlated well with x-ray transmission and fluoroscopic measurements. The data analysis for density ratios involved a small correction of about 10% for ..gamma..-shielding within the fuel tube. For hot spot examinations, limited information for this correction dictated a density ratio uncertainty of 3 to 5%.},
doi = {10.2172/5184141},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1982},
month = {Fri Jan 01 00:00:00 EST 1982}
}

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