Induced nuclear reactions: processes – systems – and elements – Reactor protection or damage prevention – Corrosion or damage prevention
Reexamination Certificate
2005-04-26
2005-04-26
Keith, Jack (Department: 3641)
Induced nuclear reactions: processes, systems, and elements
Reactor protection or damage prevention
Corrosion or damage prevention
C376S306000, C252S387000, C252S389400, C252S389510, C422S007000, C422S053000, C436S006000
Reexamination Certificate
active
06885721
ABSTRACT:
The present invention relates to a method for inhibiting stress corrosion cracking occurring on steam generator tubes in the secondary side of nuclear power plants and an inhibitor therefor. The method comprises supplying lanthanum boride as an inhibitor for stress corrosion cracking into the secondary feed water of the nuclear power plants. The method according to the present invention improves the resistance of stress corrosion cracking ten times or higher than no inhibitor, and five times or higher than the conventional inhibitor. In particular, the method according to the present invention shows a superior inhibiting effect in the lead-contaminated environment such that the complete inhibition of stress corrosion cracking can be achieved. As thus, the method can reduce the unexpected stop of operating nuclear power plants caused by the stress corrosion cracking on steam generator tubes, thereby reducing the cost required for maintaining and repairing the tubes.
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Hur Do Haeng
Kim Joung Soo
Bachman & LaPointe P.C.
Keith Jack
Korea Atomic Energy Research Institute
Korea Hydro & Nuclear Power Co., Ltd.
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