Evaluation of the leakage behavior of pressure-unseating equipment hatches and drywell heads

This paper presents the results of a recent research program to investigate the leakage behavior of pressure unseating equipment hatches. A total of thirteen tests have been conducted under various conditions to determine the pressure and temperature at which leakage through unseating equipment hatches would occur. A simple analytical model is presented that provides a good estimate of the leakage onset pressure for these tests. Because of the similarity in the sealing mechanism between unseating equipment hatches and drywell heads, the results of this program also provide insight into the leakage behavior of drywell heads. The research activities described herein are a part of the Containment Integrity Programs, which are managed by Sandia National Laboratories for the US Nuclear Regulatory Commission