摘要 |
A closing device (10) is operative to compress a closure assembly (82) and an O-ring (80) within a tubular housing (64) of a control rod drive mechanism for a nuclear reactor in order to seal the housing (64). The device (10) applies a predetermined compressive force to the closure assembly (82) and O-ring (80) and has incorporated therein an angularly movable sleeve (18) which engages a lock nut (98) and threadably advances the lock nut within the tubular housing (64) of the control rod drive mechanism so as to engage the closure assembly (82) and apply the predetermined compressive force to the closure assembly (82) and O-ring (80). After depressurization, the lock nut (98) retains the closure assembly (82) and O-ring (80) within the tubular housing (64) of the control rod drive mechanism by a predetermined residual compressive force. |