Approximately 15,000 "P" Process Aluminum caps clad with aluminum-silicon on the face and sides have been successfully canned. These caps were fabricated by the Aluminum Company of America from clad plate stock. An increase in canned slug yield of about two percent was realized from using these caps and no significant process problems indicated that the additional cost of clad plate might be off-set by the elimination of the centerless grinding now required on the side of the cap base. Therefore, processing of at least 100,000 additional aluminum-silicon clad caps is recommended, and consideration should be given at this time to completely converting from the present cap design to the aluminum-silicon clad cap.

On May 2, 1955, a request for comments on the construction and design of proposed continuous calciners was submitted to this unit by W. M. Harty. This request was complied with and a letter containing comments and suggestions on the design and construction of these calciners was written to him on May 6, 1955. The major suggestions were: 1) that the shell of the calciner be made as thin as possible, using external ribbing for structural strength, and 2) that the material of construction be type 304-L stainless steel welded with type 308-L rod. The recommendation regarding design was based on work performed by Collins, Krivobok, and this unit, which indicated that thick sections, on the order of one inch, tend to crack when subjected to thermal cycling. Type 304-L stainless steel was recommended as the material of construction because of its resistance to weld and base metal cracking, and because recent investigations indicate that a neucleation of precipitated carbides occurs after extended service in the sensitizing temperature range. On May 25, 1955, this unit received a letter from W. M. Harty stating that, on the basis of design considerations, the calciners would be fabricated from one inch thick type …