US5130081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Operation life of on-life boiling water reactors
Assignee: General Electric Co
•
Filing: 1990-04-02
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Granted: 1992-07-14
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Expires: 2010-04-02
Abstract
Abstract A method of extending the life of components of in service nuclear reactors or components of existing reactors is taught. The method involves forming a deposit on the surface coatings of metallic elements of the nuclear containment, as well as on the surfaces of encrusted internal components which are exposed to high-temperature, high-pressure water and steam. The deposit formed is a deposit of at least one member of the platinum group of metals. The deposit is formed by electroless deposition. In operation, this deposit facilitates the combination of hydrogen and oxygen to form water and thereby aids in reducing the electrochemical corrosion potential of the system to values below a critical potential that prevents stress corrosion cracking.
Inventors
- 👤 Leonard W. Niedrach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:28
CPC Classifications
G; G21; G21C; G21C17/00; G21C17/02; G21C17/022; G21C17/0225; C; C02; C02F; C02F1/00; C02F1/20; G21C13/00; G21C13/08; G21C13/087; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
94 words
The method of reducing the stress corrosion cracking of an on-line boiling water reactor having a mixed oxide crust on the surfaces of the stainless steel components thereof which are exposed to the high temperature, high pressure water of the operating boiling water reactor which comprises, forming on the surface of said mixed oxide crust a thin coating of at least one metal of the platinum group of metals, and maintaining a concentration of dissolved hydrogen gas in the water which contacts the surface coated with the thin coating of the platinum group metal.
Claim 2
Independent Claim
94 words
The method of reducing the stress corrosion cracking of an on-line boiling water reactor having a mixed oxide crust on the surfaces of the stainless steel components thereof which are exposed to the high temperature, high pressure water of the operating boiling water reactor which comprises, forming on the surface of said mixed oxide crust a thin coating of at least one metal of the platinum group of metals, and maintaining a concentration of dissolved hydrogen gas in the water which contacts the surface coated with the thin coating of the platinum group metal.
Claim 3
Dependent Claim
28 words
The method of claim 1, in which the hydrogen concentration is at least 24 ppb where the oxygen concentration is in the range of 200 to 300 ppb.
Claim 4
Dependent Claim
17 words
The method of claim 1, in which the metal of the platinum group of metals is palladium.
Claim 5
Dependent Claim
17 words
The method of claim 1, in which the metal of the platinum group of metals is platinum.
Claim 6
Dependent Claim
59 words
The method of claim 1, in which a two-step process is used in forming the thin coating of metal of the platinum group of metals and involves a first step of sensitizing and activating the surface of the crust of mixed oxides and a second step of plating the metal of the platinum group on the mixed oxide surface.
Claim 7
Dependent Claim
16 words
The method of claim 1, in which the thin coating is at least 50 Ångstroms thick.
Claim 8
Dependent Claim
16 words
The method of claim 1, in which the thin coating is at least 300 Ångstroms thick.
Claim 9
Independent Claim
101 words
A method of reducing the stress corrosion cracking of an on-line boiling water reactor having a mixed oxide crust on the surfaces of the stainless steel components thereof which are exposed to the high temperature, high pressure water of the operating reactor which comprises, forming on the surface of said mixed oxide crust a thin coating of at least one metal of the platinum group of metals, and maintaining a concentration of dissolved hydrogen gas in the hot, pressurized reactor water, the concentration of hydrogen in said reactor water being less stoichiometrically than the concentration of oxygen in said reactor water.
Claim 10
Independent Claim
101 words
A method of reducing the stress corrosion cracking of an on-line boiling water reactor having a mixed oxide crust on the surfaces of the stainless steel components thereof which are exposed to the high temperature, high pressure water of the operating reactor which comprises, forming on the surface of said mixed oxide crust a thin coating of at least one metal of the platinum group of metals, and maintaining a concentration of dissolved hydrogen gas in the hot, pressurized reactor water, the concentration of hydrogen in said reactor water being less stoichiometrically than the concentration of oxygen in said reactor water.
Claim 11
Dependent Claim
15 words
The method of claim 8, in which the hydrogen concentration is at least 24 ppb.
Claim 12
Dependent Claim
15 words
The method of claim 8, in which the hydrogen concentration is at least 100 ppb.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-07-14 | 1996-01-13 | 1996-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-14 | 2000-01-13 | 2000-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-14 | 2004-01-13 | 2004-07-14 | $7700.00 | Window Closed / Lapsed |