Nuclear reactor removable radial shielding assembly having a self-bowing feature

Patent · 31 December 1977

OSTI ID:862998

Pennell, William E ^[1]; Kalinowski, Joseph E ^[2]; Waldby, Robert N ^[3]; Rylatt, John A ^[4]; Swenson, Daniel V ^[1]

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1. Greensburg, PA
2. Smithton, PA
3. New Stanton, PA
4. Monroeville, PA

A removable radial shielding assembly for use in the periphery of the core of a liquid-metal-cooled fast-breeder reactor, for closing interassembly gaps in the reactor core assembly load plane prior to reactor criticality and power operation to prevent positive reactivity insertion. The assembly has a lower nozzle portion for inserting into the core support and a flexible heat-sensitive bimetallic central spine surrounded by blocks of shielding material. At refueling temperature and below the spine is relaxed and in a vertical position so that the tolerances permitted by the interassembly gaps allow removal and replacement of the various reactor core assemblies. During an increase in reactor temperature from refueling to hot standby, the bimetallic spine expands, bowing the assembly toward the core center line, exerting a radially inward gap-closing-force on the above core load plane of the reactor core assembly, closing load plane interassembly gaps throughout the core prior to startup and preventing positive reactivity insertion.

• DOE Contract Number: E(11-1)-2395
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4070241
• OSTI ID: 862998
• Country of Publication: United States
• Language: English

Related Subjects

/376/976/
allow
allow removal
assemblies
assembly
below
bimetallic
blocks
bowing
breeder reactor
center
center line
central
closing
cooled fast
core
core assemblies
core assembly
core support
criticality
exerting
expands
fast-breeder
fast-breeder reactor
feature
flexible
gap-closing-force
gaps
heat-sensitive
hot
increase
inserting
insertion
interassembly
inward
line
liquid-metal-cooled
liquid-metal-cooled fast
liquid-metal-cooled fast-breeder
load
material
metal-cooled fast
metallic spin
nozzle
nuclear
nuclear reactor
operation
periphery
permitted
plane
portion
position
positive
power
power operation
prevent
preventing
prior
radial
radial shielding
radially
radially inward
reactivity
reactor
reactor core
refueling
refueling temperature
relaxed
removable
removable radial
removal
replacement
self-bowing
shielding
shielding assembly
shielding material
spine
standby
startup
support
surrounded
temperature
throughout
tolerances
various
vertical
vertical position