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Samples of M1 single-base propellant were exposed to 10{sup 5}, 10{sup 6}, and 10{sup 7}r of Co{sup 60} gamma rays. Burning rates were determined over a pressure range of 600 to 2600 psi at -40{degrees}, 21{degrees}, and 71{degrees}C. A statistical study indicated no significant change in the burning rate and a small but statistically significant increase (6%) in the exponential factor n after the 10{sup 7}r dose. Visible deterioration resulted, as the color changed from yellow to dark brown and the surface became uneven. In view of these marked visible effects, the slight change in burning rate is surprising. One sample exposed to 5 {times} 10{sup 8}r showed severe blistering, swelling, and contraction, and embrittlement causing fracture. Nitrogen Taliani tests conducted at 110{degrees}C indicated that the decomposition rate is decreased by exposure to 10{sup 5}r, is decreased less by 10{sup 6}r, and remains unchanged after 10{sup 7}r exposure. Chemical analysis showed that the percentage of 2-nitrodiphenylamine increases with dose by a factor of 7 at 10{sup 7}r, while, at the same time, the nitrogen content of the nitrocellulose decreases with increasing dose. This indicates that a substantial part of the nitrocellulose decomposition product had reacted with the diphenylamine stabilizer. It …

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Report documenting the progress of the Army Gas-Cooled Reactor Systems Program to develop a mobile nuclear power plant for military field operation.

The horizontal control rods presently installed in the older Hanford Reactors have inadequate heat transfer characteristics for present and predicted future operation of the reactors. Continued graphite stack distortion, coupled with higher graphite temperatures, has resulted in ECR failure during reactor operation, such as swelling of the outer aluminum sheaths to the extent that rod movement in the graphite channel is severely restricted. Continued graphite stack distortion will tend to further aggravate the problem of rod operation. A new HCR design concept,was developed by P. H. Hutton of Reactor Design, IPD, to alleviate some of the pressing operational problems. Prior to the acceptance of such a design, the important rod operating parameters should be known to some degree of accuracy. This study was conducted to detexmine, by calculational methods, the temperature distributions that could be expected to occur in such an HCR when used at the present operating power levels and at 120% of the present power levels.

Recent (HCR) Horizonal Control Rod operating problems at the K Reactors, caused primarily by graphite stack distortion, have stimulated several designs of HCR`s capable of operating under adverse conditions. One such design is an aluminum HCR, not completely dissimilar to the present HCR`s, conceived by the Research and Engineering Operation of I.P.D. The successful use of aluminum as a structural material is strongly dependent upon the operating temperature of the aluminum. This study was conducted to determine anticipated operating temperatures of the HCR during reactor operation at the present K Reactor conditions.

The steadily increasing graphite stack distortion in the K Reactors has caused serious operating problems with the existing horizontal control rods. To compound the seriousness of the problems, the high level of reactor operation today and the anticipated higher level of operation in the future demands a reliable control rod system. A flexible control rod has been designed by Reactor Design, IPD, to facilitate reliable operation of the HCR system in spite of channel bowing arising from graphite stack distortion. This flexible control rod design is radically different from the existing K Reactor control rods and in fact, is more closely aligned to the control rods now in use at the older Hanford Reactors. The major difference of the new rod is the elimination of intimate contact between the poison-containing section of the rod and the cooling water. Such a change in design as described above could result in significant changes in the operating temperatures of the rod proper. This study was undertaken to provide a calculated indication of the temperature changes and the relative magnitude of such changes relative to reactor power levels, graphite temperatures, coolant temperatures, etc. In addition to this basic information, the scope of the study …

A modification program is now in progress at the C and K Reactors consisting of an extensive renovation of the graphite channels in the vertical safety rod ststems. The present VSR channels are being enlarged by a graphite coring operation and channel sleeves will be installed in the larger channels. One problem associated with the coring operation is the danger of damaging top thermal shield cooling tubes located close to the VSR channels to such an extent that these tubes will have to be removed from service. If such a condition should exist at one or a number of locations in the top shield of the reactors after reactor startup, the question remains -- what would the resulting temperatures be of the various components of the top shields? This study was initiated to determine temperature distributions in the top shield complex at the C and K Reactors for various top thermal shield coolant system conditions. Since the top thermal shield cooling system at C Reactor is different than those at the K Reactors, the study was conducted separately for the two different systems.

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This report discusses a comparative irradiation test of fuel elements of N-fuel uranium composition at Hanford.

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Irradiation-induced moderator distortion has plagued the Hanford reactors from their earliest days until the present. The first-manifestation of graphite distortion was in the form of expansion of the B, D and F stacks. It was found that expansion was very temperature-dependent and could be reversed by raising the graphite operating temperature. The DR, H, C and K Reactors were designed with provisions to minimize, or accommodate expansion. It was not until after the K Reactors had been designed that graphite contraction was recognized as a threat to stack life. Under the present operating conditions, contraction is largely dependent upon neutron flux levels. To date, this study has been largely concerned with the K Reactors, since the vast bulk of the distortion data available is from the Ks. This study not only attempts to explain the mechanisms by which the K Reactors arrived at their present state of distortion but also provides a basis for forecasting future distortion. An understanding of the nature and magnitude of the forces at work within the stacks will enhance the possibility of devising means of conteracting the present trends.

A series of tests was conducted on a thrust bearing and two roller bearings to determine the effects of zero radial load and reversing thrust load on bearing performance. The results, for an accumulated test time of 5 hours, showed that a ball bearing could operate successfully under the stated conditions both at constant speed and during acceleration and deceleration. The test test continued until failure of one roller bearing. The failure was caused by loss of clearance because of buildup of cage debris on the races. Test speeds included one hour r operation above 27,500 rpm.

This test was conducted to determine the adequancy of the Core Band to withstand the forces imposed upon it during Reactor Operation.

At present there seem to be some uncertainties concerning the needs of rupture detection for the co-producer programs Also in question is the method by which ruptures of the target elements should be detected and located. The purpose of this report is to discuss the waste and hazard control of tritium (H{sup 3}) (the product of the co-producer program), which will determine rupture detection needs, and to discuss methods by which rupture detection and location may be accomplished. The scope of the report considers first, adaptation of the present rupture monitoring system, and second, monitoring systems using H{sup 3} analyzers, together with the costs and time required to develop and use each method of rupture detection.

The tissue dose calculations of Kinney were used to calculate several importance functions associated with the dose from primary and secondary particles in the tissue due to penetration of an aluminum shield by a solar-flare proton spectrum. Secondary particles produced in the shield were not considered. (auth)

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Using the straight-ahead approximation, nucleon-meson cascade calculations were carried out for several solarflare proton spectra incident on a shield. The shield material has approximately the properties of aluminum. Both spherical-shell and slab geometries are considered. (auth)

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The recently completed 25-inch hydrogen bubble chamber combines excellent picture quality with a fast operating cycle. The chamber has a unique optical system and is designed to take several pictures each Bevatron pulse, in conjunction with the Bevatron rapid beam ejection system.