PLUG FOR AN ACCESS HOLE DISPOSED IN THE BIOLOGICAL SHIELD OF NUCLEAR REACTORS

Patent · Mon Oct 17 04:00:00 EDT 1960

OSTI ID:4792720

A plug is designed for closing a vertical access hole of a gas-cooled nuclear reactor. The plug comprises a plug body of general cylindrical shape adapted to be positioned in the access hole tube and resting with a shoulder on a corresponding shoulder provided on the access hole wall. This position of the plug is secured by locking means comprising an annular series of balls resting in openings in the wall of a cylindrical collar sliding on the upper portion of the said plug body and abutting these balls bl spring action against a further annular shoulder on the plug body, this shoulder having the shape of a truncated cone, so that the balls are pressed outwards in order to engage an annular groove of the access hole wall. Some of the balls are provided with locking means comprising an axially movable bolt withib its axial direction variable cross section, so that in the highest position of this bolt any inward movement of the associated ball is prevented. The bolt is connected with a piston actuated by the gas pressure in the reactor against the action of a weak spring, so that the bolt is held ib the said highest position by said gas pressure. The bolt further controls the contact of an electric circuit for indicating the locked state of the plug. (NPO)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-16-015853
• OSTI ID: 4792720
• Report Number(s): FR 1247092
• Country of Publication: France
• Language: English

Related Subjects

CLOSURES
CONTROL SYSTEMS
GAS COOLANT
MACHINE PARTS
MECHANICAL STRUCTURES
PATENT
REACTOR TECHNOLOGY
REACTORS
SHIELDING