The thirteenth meeting of the Graphite Expansion Committee was held on January 10, 1947. A summary of meeting topics follow. The horizontal bowing of Tube 4494-D in the top corner of the pile is considerably greater than the bowing which can be attributed to graphite expansion at this elevation in the pile, indicating that the top layers of graphite are being dragged outward by expansion of the underlying layers. Such a phenomenon could shear the vertical thimbles at a point just below the thermal blocks. Equipment is to be developed for measuring any eccentricity between the rod guide and a section of the thimble located just below the end of the guide. Jacking tests using forces up to 4000 lbs. on gun-barrels which show binding have demonstrated that binding is still present at these high forces. It was recommended that no further jacking tests be performed on gun-barrels which are known to exhibit binding. Rupture tests on Tube 4082-B caused failure of the rear Van Stone joint after the tube had been stretched {1/2} inch. The amount of tube stretch before failure of the flames will probably be affected primarily by corrosion of the flange and, for the same reason, …

At this time it is desirable that preliminary estimates be made of the manpower, equipment, space, layout and facility requirements of the analytical section for the 234-5 Project. To arrive at these requirements a rough estimate of the required analyses, their scope and their frequency has been compiled. This is expected to serve as a basis for the Laboratories Division to outline their space and equipment requirements as soon as possible and to assemble the required personnel for operation later. Crucial elements encountered in the process are classed as light impurities or as metallurgical impurities. The light elements are undesirable due to the {alpha}, n reaction with plutonium. The metallurgical impurities are undesirable since they change the physical properties of plutonium. The light elements undesirable in the finished product and the approximate tolerances (in ppM of plutonium) acceptable for each are listed assuming all other elements listed are absent. A list of the undesirable metallurgical impurities with the tolerances (again expressed in ppM of plutonium) for each element, assuming the other elements are absent are given.

This document presents details of the specifications for the chemical development laboratory, in accordance with project 234-5.