The increasing incidence of leaking process tubes, and the approaching end of the useful life of process tubes in the C and K Reactors, have focused attention upon the various sources of aluminum process tube leaks. Further, the replacement of large numbers of process tubes with new ones, also of aluminum, will require continued attention to these sources to make efficient use of the new tubes. One of the sources of process tube leaks is the corrosion that attacks the interior surface of the process tube. The factors influencing the extent of this corrosion attack are varied and complex, and in recent years, the corrosion service conditions have become increasingly more severe. Each of the factors involved in determining the rate of corrosion attack has thus become individually more important, and the need to understand the inter-relationships among them has increased. It is the purpose of this report to discuss the technical factors contributing to the internal corrosion of the process tubes, to review the way some of these factors have varied in the past, to examine the means available for evaluating the extent to which corrosion has damaged the tube walls, to comment upon the ways in which knowledge …

Tests of Cambridge absolute filters, Model Sl-071, specified for use in the GCR-ORR Loop No. 2 as full-flow, primary coolant fiiters were completed. kD.O.P/ (dioctylphthalate) efficiency tests were performed on three filters in the as-received condition, on two filters following canning and thermal cycling, and on one of the canned fiIters following bsking out. None of the three units met the design criteria of 99.97% efficiency for removal of 0.3 micron particles in the as-received condition. The postthermal cycle efficiencies of the canned fiIters were slightly higher than their respective as-received efficiencies. At the corapletion of testing, the two fiiters canned for installation in the reactor facility had measured efficiencies of 99.855% and 99.93%. These values were judged acceptable for the intended application/su The thermal cycling of the two canned filters and the subsequent baking out of one of these units demonstrated that a limited amount of off-gas products would be given off/su Pressure drop tests were performed on the canned fiiters with instrument air (ambient temperature, atmospheric pressure) over a flow rate range of 150 to 530 lb/hr. Curves of pressure drop across each fiIter versus Reynolds number were plotted for air and He. (auth)

The maximum stress calculated for the SMl-1 reactor vessel closure studs occurs during operation at full power. This value is 27,180 psi of which 19,800 psi is tension and 7380 psi bending. This stress does not include a stress concentration factor for effect of threads. It was eonservatively assumed the studs were initially tightened to a code allowable stress of 20,000 psi as specified in the ASME Code rather than the lesser stress obtained by the normal operating procedure. The maximum calculated stress occurs at the outside surface of the cover where the stress ranges from 318 psi in tension to 90,660 psi in compression. The alternating stress is 50,000 psi. According to the Navy Code for a stress range of 50,000 psi, the eover material ean safely undergo a maximum of 1600 cycles. It was estimated that the SM-1 will go through approximately 000 startup and shutdown cycles during a 20-yr life period, so the calculated stress is regarded as safe. For a transient eondition of 30 deg F/hr during heat-up, approximate temperature differences between the inside and outside surfaces of the cover were obtained. Temperature differentials between the inside and outside surfaces of the cover are increased by …

The report comprises seven sections. A separate abstract was prepared for each section. (J.R.D.)