Development of a fabrication process and the manufacture of 95 PRTR process tubes demonstrates that the commercial fabrication of high quality Zircaloy-2 pressure tubing is feasible.

Since the calculation of the PRTR energy distribution was first carried out by J. R. Triplett, the design has become sufficiently fixed to allow a refinement of his values. The present analysis, also, includes a calculation of the fraction of energy which is released in the shroud and process tubers that flows to the primary coolant to the top and bottom shield coolant is taken into consideration. Nuclear data used in the original calculations still appears satisfactory and is, therefore, utilized in the present analysis.

The relative neutron capture gamma production in several prospective iron thermal shielding materials for the New Production Reactor was measured to determine the merit of adding boron to the metal. It was found that for the beam geometry the used addition of 1 1/2 percent boron to the iron before casting reduced the soft gamma production by a factor of 6.5 and the hard gamma production by a factor of 10. No attempt was made to measure gamma or neutron transmissions.