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Performance of Metal and Polymeric O Ring Seals during Beyond-Design-Basis Thermal Conditions



Jiann C. Yang, Edward J. Hnetkovsky, Doris L. Rinehart, Marco G. Fernandez, Felix Gonzalez, Joseph Borowsky


This paper summarizes the small scale thermal exposure test results of the performance of metallic and polymeric O- ring seals typically used in radioactive material transportation packages. Five different O-ring materials were evaluated: Inconel/silver, ethylene-propylene diene monomer (EPDM), polytetrafluoroethylene (PTFE), silicone, butyl, and Viton. The overall objective of this study is to provide test data and insights to the performance of these O-ring seals when exposed to beyond-design-basis temperature conditions due to a severe fire. Tests were conducted using a small-scale stainless steel pressure vessel pressurized with helium to 2 bar or 5 bar at room temperature. The vessel was then heated in an electric furnace to temperatures up to 900 C for a pre-determined period (typically 8 h to 9 h). The pressure drop technique was used to determine if leakage occurred during thermal exposure. Out of a total of 46 tests performed, leakage (loss of vessel pressure) was detected in 13 tests.
Polymer Testing


Keywords: Cask, shipping package, fires, beyond-design-basis conditions, seals, spent fuels


Yang, J. , Hnetkovsky, E. , Rinehart, D. , Fernandez, M. , Gonzalez, F. and Borowsky, J. (2016), Performance of Metal and Polymeric O Ring Seals during Beyond-Design-Basis Thermal Conditions, Polymer Testing, [online], (Accessed July 16, 2024)


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Created December 28, 2016, Updated November 10, 2018