Sealed stopper for an opening in a tubing for joining a chamber and a piping, particularly in the steam generator of a nuclear pressurised water reactor

摘要

A sealed stopper for an opening in a tubing for joining a chamber and a piping including a fastening ring is provided. The stopper includes a rigid bearing plate and a sealing member carried by the bearing plate, and includes a seal having a planar and flexible central portion with a reduced thickness extending below the bearing plate and a peripheral portion radially deformable by a central expander of the peripheral portion against the inner surface of the fastening ring.