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US3774010A Expired / Lapsed US ⏱️ 0.0 years remaining

Pressurization of fuel rods by laser drilling and sealing

Assignee: Babcock and Wilcox Co
•
Filing: 1971-01-08
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Granted: 1973-11-20
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Expires: 1991-01-08
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Abstract

Abstract A method of pressurizing a presealed fuel rod containing nuclear fuel with an inert gas under pressure. A loaded fuel rod is inserted into a pressure chamber, the latter is sealed and a vacuum is applied. While maintaining the vacuum in the chamber, the fuel rod is punctured with a fine hole by means of a laser beam. The air inside the vessel is drawn out into the chamber until it reaches equilibrium therein. The chamber is then filled with an inert gas under pressure and this gas is forced inside the fuel rod through the aforesaid hole. When the pressure inside the fuel rod reaches equilibrium with the chamber, the hole is sealed by means of a laser beam and the fuel rod is removed from the chamber.

Inventors

  • 👤 W Heer
  • 👤 E Decarli

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 14:01
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/02; G21C3/04; G21C3/06; G21C3/10; Y; Y02; Y02E; Y02E30/00; Y02E30/30

Claims Analysis

Total Claims: 26
Claim 1
Independent Claim 19 words
A sequential method of pressurizing a sealed fuel rod of the loaded nuclear variety in step wise order, Comprising:
Claim 2
Dependent Claim 19 words
A sequential method of pressurizing a sealed fuel rod of the loaded nuclear variety in step wise order, Comprising:
Claim 3
Dependent Claim 18 words
Positioning a sealed fuel rod having a nuclear fuel therein in a predetermined location in a closed chamber.
Claim 4
Dependent Claim 18 words
Positioning a sealed fuel rod having a nuclear fuel therein in a predetermined location in a closed chamber.
Claim 5
Dependent Claim 7 words
Evacuating said chamber to provide a vacuum,
Claim 6
Dependent Claim 7 words
Evacuating said chamber to provide a vacuum,
Claim 7
Dependent Claim 7 words
Evacuating said chamber to provide a vacuum,
Claim 8
Dependent Claim 7 words
Evacuating said chamber to provide a vacuum,
Claim 9
Dependent Claim 22 words
The method of claim 1, wherein in step 3 said light energy is between about 13,000 and 110,000 joules per square centimeter.
Claim 10
Dependent Claim 24 words
The method of claim 1, wherein in step 3 about 52,360 joules per square centimeter is applied to said rod of the Zircaloy variety.
Claim 11
Dependent Claim 46 words
Applying between about 160 and 740,000 joules of light energy of the laser variety per square centimeter to a desired location on the surface of said rod to produce a puncture which communicates with the interior of the same, purging said fuel rod through said puncture,
Claim 12
Dependent Claim 46 words
Applying between about 160 and 740,000 joules of light energy of the laser variety per square centimeter to a desired location on the surface of said rod to produce a puncture which communicates with the interior of the same, purging said fuel rod through said puncture,
Claim 13
Dependent Claim 46 words
Applying between about 160 and 740,000 joules of light energy of the laser variety per square centimeter to a desired location on the surface of said rod to produce a puncture which communicates with the interior of the same, purging said fuel rod through said puncture,
Claim 14
Dependent Claim 46 words
Applying between about 160 and 740,000 joules of light energy of the laser variety per square centimeter to a desired location on the surface of said rod to produce a puncture which communicates with the interior of the same, purging said fuel rod through said puncture,
Claim 15
Dependent Claim 10 words
Pressurizing said chamber to a pressure above atmospheric pressure, and
Claim 16
Dependent Claim 10 words
Pressurizing said chamber to a pressure above atmospheric pressure, and
Claim 17
Dependent Claim 10 words
Pressurizing said chamber to a pressure above atmospheric pressure, and
Claim 18
Dependent Claim 10 words
Pressurizing said chamber to a pressure above atmospheric pressure, and
Claim 19
Dependent Claim 29 words
The method of claim 1, wherein between steps 3 and 4 said chamber is evacuated to 20 u and allowed to reach equilibrium prior to pressurization of said chamber.
Claim 20
Dependent Claim 40 words
The method of claim 1, wherein communication of said puncture with the interior of said rod as a result of step 3 further comprises the step of observing a reduction of the vacuum produced in said chamber by step 2.
Claim 21
Dependent Claim 18 words
Reapplying said light energy to an enlarged area around the periphery of said puncture to seal the same.
Claim 22
Dependent Claim 18 words
Reapplying said light energy to an enlarged area around the periphery of said puncture to seal the same.
Claim 23
Dependent Claim 18 words
Reapplying said light energy to an enlarged area around the periphery of said puncture to seal the same.
Claim 24
Dependent Claim 18 words
Reapplying said light energy to an enlarged area around the periphery of said puncture to seal the same.
Claim 25
Dependent Claim 24 words
The method of claim 1, wherein in step 4 said chamber is pressurized to 400 pounds per square inch prior to sealing said puncture.
Claim 26
Dependent Claim 24 words
The method of claim 1, wherein in a final step, said chamber is again evacuated after the sealing of said puncture in step 5.

References Cited (Backward Citations)

US3033972A Cited
US3151231A Cited
US3210171A Cited
US3045108A Cited
US3188446A Cited
DE2015784A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-11-19 1977-05-21 1977-11-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-11-19 1981-05-21 1981-11-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-11-19 1985-05-21 1985-11-20 $7700.00 Window Closed / Lapsed

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