DESIGN AND OPERATION OF FORCED-CIRCULATION CORROSION TESTING LOOPS WITH MOLTEN SALT

Standardized test facilities were developed and operate for investigating the compatibility of structural materials and flowing molten fluoride salts. The standard loop accommodates various combinations of materials, fluid, flow, rates, and temperature differentials and permits fabrication of components in sufficient quantity for cost reduction. The test loop consists of a pump, two heated sections, a cooled section, a drain tank, and a frozen-plug-type valve. Automatic controls and equipment were developed to prevent solidification of the salt mixtures (mp, 800 to 1100 un. Concent 85% F) in the event of a loss of power. Most test loops were fabricated of 0.5-in.-OD, 0.045-in.-wall tubing, and operate with a temperature differential of up to 200 un. Concent 85% F, a maximum wall temperature in the range 1200 to 1500 un. Concent 85% F, and a salt flow rate of up to 3 gpm. Twenty-five test loops were operated for an accumulated operating time of 290,00 hr. Individual loops were operated continuously for more than one year. (auth