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

The invention relates to a sealed stopper (10) for an opening in a tubing (6) for joining a chamber and a piping comprising a fastening ring (8). The stopper (10) comprises a rigid bearing plate (20) and a sealing member (30) carried by said bearing plate (20), and includes a seal having a planar and flexible central portion with a reduced thickness extending below the bearing plate (20) and a peripheral portion (32) radially deformable by a central expansion means (40) of the peripheral portion against the inner surface of the fastening ring (8).