Temperature environment for 9975 packages stored in KAC

Daugherty, W. L.¹ 

[1] Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

关键词: K-area;    viton;    service life;   

DOI  :  10.2172/1215491
RP-ID  :  SRNL-STI--2015-00441
PID  :  OSTI ID: 1215491

美国|英语

来源: SciTech Connect

【 摘 要 】

Plutonium materials are stored in the K Area Complex (KAC) in shipping packages, typically the 9975 shipping package. In order to estimate realistic degradation rates for components within the shipping package (i.e. the fiberboard overpack and O-ring seals), it is necessary to understand actual facility temperatures, which can vary daily and seasonally. Relevant facility temperature data available from several periods throughout its operating history have been reviewed. The annual average temperature within the Crane Maintenance Area has ranged from approximately 70 to 74 ?��F, although there is significant seasonal variation and lesser variation among different locations within the facility. The long-term average degradation rate for 9975 package components is very close to that expected if the component were to remain continually at the annual average temperature. This result remains valid for a wide range of activation energies (which describes the variation in degradation rate as the temperature changes), if the activation energy remains constant over the seasonal range of component temperatures. It is recommended that component degradation analyses and service life estimates incorporate these results. Specifically, it is proposed that future analyses assume an average facility ambient air temperature of 94 ?��F. This value is bounding for all packages, and includes margin for several factors such as increased temperatures within the storage arrays, the addition of more packages in the future, and future operational changes.