This test authorizes installation of up to ten non-overbore size zirconium smooth-bore process tubes into KW Reactor and continued charging of these tubes with KVNS fuel elements until authorized by other means (Process Standards or PITA) or until this test is terminated. While the test authorizes up to 10 tubes, only two process tubes are immediately available and are all that will be planned for in the initial installation and charging. Goal exposure will be set at 800 MWD/T.

Reduced process water treatment costs and incidental benefits of smaller hexavalent chromium discharge to the Columbia River provided incentives to conduct a half-reactor production test. The sodium dichromate (Na{sub 2} Cr{sub 2} O{sub 7}2H{sub 2}O) concentration in process water supplied to the far side of 105-C was lowered from a nominal value of 1.8 to 1.0 parts per million (ppM). This test was started September 26, 1960 and is still in progress. However, a sufficient amount of data is available now to permit an interim evaluation of the corrosion effects noted as a result of the change inhibitor concentration.

The impregnation process of the graphite used for investigations of spalling is described. Polished graphite specimens were examined at room temperature using bright field metallographic techniques. The gas evolution characteristics of impregnated graphite were also determined. Results indicated that the amount of impregnant introduced during the fourth impregnation cycle could be a critical factor in causing spalls in the manufacturing process. The permeability of the impregnated graphite was found to increase with the temperature to which the impregnated graphite was heated. Studies showed that the most significant changes in the impregnant and in the gas evolution occurred in the temperature range of 100 to 600 deg C. These results suggested that a slower heating rate during carbonization is likely to reduce spalling. A tentative mechanism for spalling is offered. (M.C.G.)

: : 9 7 7 8 6 9 : = 7 9 9used during the fluorination of fused-salt fuels and subsequent associated operations in the Oak Ridge National Laboratory (ORNL) Fluoride Volatility Process was evaluated. Corrosive attack is reported as mils per month based on molten salt residence time or mils per hour based on fluorine exposure time. Two fluorinators were used in the VPP to carry out the fluorination reactions. These vessels, Mark I and Mark II, were fabricated into right cylinders, approx 4 1/2 ft in height, from the same heat of L (low carbon nickel. The first vessel contained equimolar NaF- ZrF/sub 4/ or NaF-ZrF/sub 4/-UF/sub 4/ (48-48-4 mole%) for approx 1250 hr at 600 to 725 deg C. Over a period of 61 hr, 57,500 standard liters of F/sub 2/ were sparged into the slats. This constituted a F/sub 2/:U mole ratio of 3:1 beyond theoretical requirements. The Mark II fluorinator contained fluoride salts of approxi-mately the same compositions plus small additions of PuF/sub 4/ during three runs. The salts were kept molten at 540 to 730 deg C for approx 1950 hr and about sixty 500 standard liters of F/sub 2/ were sparged into the …

In support of the High Flux Isotope Reactor program, experimental determinations were made of friction factors, burnout heat fluxes, and average and local nonboiling heattransfer coefficients for forced-convection flow of water through this aluminum and nickel rectangular channels under the following conditions: heat flux = 0.1 x 10/sup 6/ to 7.4 x 10/sup 6/ Btu/hr - ft/sup 2/, velocity = 10 to 85 fps, Reynolds number = 9,000 to 270,000, pressure = 1 to 39 atmospheres absolute, flow gap = 0.043 to 0.057 in., and heated length = 12 and 18 in. A few tests were made to ascertain the effect of an axially oriented cylindrical spacer strip on surface temperature distribution and burnout heat flux. The results of these studies, are in reasonably good agreement with accepted ccrrelations. The friction factors are in satisfactory agreement with the Moody chart for the relative roughness of the test sections used, the burnout heat fluxes are well reproduced by the Soviet Zenkevich-Subbotin correlation, and the local and average heat-transfer coefficients are slightly larger than values predicted by the Hausen and Sieder-Tate equations. Miscellaneous experimental and analytical HFIR heat-transfer studies are included. (auth)