SWAGING OF URANIUM DIOXIDE. Annaul Report No. 1, May 1960-June 1961

Technical Report · Mon Jul 31 04:00:00 EDT 1961

OSTI ID:4143499

Frigerio, G; Ferrari, H M

Over 70 bars of many different diameters and thicknesses and 30 cm long were swaged to determine the importance of the cladding diameter-to-thickness ratio. It was found that for bars having D/sub O/T ratios under 18, the density increases with increasing reductions in area of fuel. For intermediate D/sub O/T ratios from 18 to 26 the density reaches a maximum after about 30% reduction in area and levels off with further reduction. However, with values of D/sub O/T of 29 and over, the density reaches a maximum and then decreases with further reductions in area. Several reactor length bars were swaged using a semiautomatic feeding device and compared with those obtained by hand feeding. It was found that bars swaged with the feeding device had better surface finish and were straighter. Using the feeding device, stainless steel tubes with wall thicknesses as low as 15 mils were swaged. Stainless steel bars of reactor length loaded with fused UO/sub 2/ pneumatically vibrated to 80--82% T. D. were swaged to densities of 92% T.D. or over with 2 passes and a reduction of fuel area of approximately 20%. The variation in density along the bars was an acceptable plus or minus 1% T.D. maximum; in some cases the deviations were only plus or minus 0.5%. Measurements of the thermal conductivity of fused UO/sub 2/ were obtained for 3 samples swaged to different densities. Values were obtained at 150 to 500 deg C. The thermal conductivity values for swaged UO/sub 2/ pellets are lower by 30% at 150 deg than those obtained by other workers. As the temperature is increased the thermal conductivity for swaged UO/sub 2/ is only 20 to 25% below those for pellets at 500 deg C. It must be noted that a similar test performed on a plain stainless steel rod gave a result 8% lower than the normal figare. Preliminary tests showed that very little UO/sub 2/ loss by erosion occurs in swaged UO/sub 2/ bars in a static pressurized water environment. (auth)

• Research Organization: FIAT. Sezione Energia Nucleare, Turin
• NSA Number: NSA-18-002198
• OSTI ID: 4143499
• Report Number(s): EURAEC-118; FN-E-10
• Country of Publication: United States
• Language: English

Related Subjects

COMPACTING
CONFIGURATION
DEFORMATION
DENSITY
DISTRIBUTION
EROSION
FABRICATION
FUEL CANS
FUEL ELEMENTS
LOSSES
MEASURED VALUES
METALS, CERAMICS, AND OTHER MATERIALS
PRESSURE
RODS
SERVOMECHANISMS
STAINLESS STEELS
SURFACES
THERMAL CONDUCTIVITY
THICKNESS
TUBES
URANIUM DIOXIDE
VIBRATIONS
WATER