Technical report outlining the investigation of corrosion on MTR type fuel elements for the Shielding Reactor in filtered water. Report includes two basic types of protection: element pretreatment by either anodizing or alodizing, and solution control using nitric acid to maintain a pH of 5.5 to 6.5 or the addition of 60 ppm sodium chromate as an inhibitor. [From Abstract]

Abstract: This technical report consists of series of drawings of the instrument with the following explanation. The modification of the Simpson Methane flow proportional counter consists of a means for inserting and replacing samples into the chamber through an air-lock device which avoids the introduction of even a small quantity of air into the active volume of the chamber. This is accompanied by sweeping out the small volume of the air-lock containing the sample with methane gas before the sample is introduced into the chamber -- this sweeping out requiring only a few seconds. The mechanical construction is somewhat simplified over that employed in the Simpson counter design, although the electrical and counting characteristics are essentially duplicates of those employed in the Simpson version. Voltage plateaus about 400 volts long, flat within 1% per 100 volts are obtained with the counter, with the operating point at about 2500 volts for methane at one atmosphere pressure. A plateau extending over a range of about 40% variation in amplification factor is obtained. Standard samples have been checked to standard deviation of +/-0.3% over a period of one year. The counter is rather gas-tight and is ready for use within about ten minutes …

A preliminary report has shown the potential importance of organic reactor coolants to Hanford technology. The salient points are complete avoidance of corrosion problems and accomplishment of DPR performance with low pressure technique. The recommendation of the report that loop tests be made at Hanford is to be acted upon by Recirculation Technology Unit as soon as organic coolant material is received. To insure starting this experimental work fully abreast of the information available, a trip to sites working with organic coolants was made. Specifically, data were sought on practical details of design for handling organic coolants, heat transfer and fouling characteristics, corrosion of materials, and hazards of handling organics.