CSR behavior and aging model for the Viton?? Fluorelastomer O-rings in the 9975 shipping package

Mcwilliams, A. J.¹  Daugherty, W. L.¹  Skidmore, T. E.¹ 

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

关键词: TEMPERATURE RANGE 0273-0400 K;    GASKETS;    VITON;    SERVICE LIFE;    AGING;    FORECASTING;    STORAGE;    STRESS RELAXATION;    FISSIONABLE MATERIALS;    COMPRESSION;    PACKAGING;    TEMPERATURE RANGE 0400-1000 K;   

DOI  :  10.2172/1238595
RP-ID  :  SRNL-STI--2015-00683
PID  :  OSTI ID: 1238595
Others  :  TRN: US1600539

美国|英语

来源: SciTech Connect

【 摘 要 】

The 9975 Type B shipping package is used within the DOE complex for shipping special nuclear materials. This package is re-certified annually in accordance with Safety Analysis Report for Packaging (SARP) requirements. The package is also used at the Savannah River Site as part of the long-term storage configuration of special nuclear materials. As such, the packages do not undergo annual recertification during storage, with uncertainty as to how long some of the package components will meet their functional requirements in the storage environment. The packages are currently approved for up to 15 years storage, and work continues to provide a technical basis to extend that period. This report describes efforts by the Savannah River National Laboratory (SRNL) to extend the service life estimate of Viton?? GLT and GLT-S fluoroelastomer O-rings used in the 9975 shipping package. O-rings of both GLT and GLT-S compositions are undergoing accelerated aging at elevated temperature, and are periodically tested for compression stress relaxation (CSR) behavior. The CSR behavior of O-rings was evaluated at temperatures from 175 to 400 ?��F. These collective data were used to develop predictive models for extrapolation of CSR behavior to relevant service temperatures (< 156 ?��F). The predictive model developed from the CSR data conservatively indicates a service life of approximately 37 years for Viton GLT O-rings at the maximum effective service temperature of 156 ?��F. The estimated service life for Viton GLT-S O-rings is significantly longer.