Hydro-ball in-core instrumentation system and method of operation

Patent · Mon Jan 01 00:00:00 EST 1990

OSTI ID:867577

Tower, Stephen N ^[1]; Veronesi, Luciano ^[2]; Braun, Howard E ^[3]

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1. Washington Township, Westmoreland County, PA
2. O'Hara Township, Allegheny County, PA
3. Pittsburgh, PA

A hydro-ball in-core instrumentation system employs detector strings each comprising a wire having radiation sensitive balls affixed diametrically at spaced positions therealong and opposite tip ends of which are transportable by fluid drag through interior passageways. In the passageways primary coolant is caused to flow selectively in first and second opposite directions for transporting the detector strings from stored positions in an exterior chamber to inserted positions within the instrumentation thimbles of the fuel rod assemblies of a pressure vessel, and for return. The coolant pressure within the detector passageways is the same as that within the vessel; face contact, disconnectable joints between sections of the interior passageways within the vessel facilitate assembly and disassembly of the vessel for refueling and routine maintenance operations. The detector strings may pass through a very short bend radius thereby minimizing space requirements for the connections of the instrumentation system to the vessel and concomitantly the vessel containment structure. Improved radiation mapping and a significant reduction in potential exposure of personnel to radiation are provided. Both top head and bottom head penetration embodiments are disclosed.

• Research Organization: Westinghouse Electric Corp., Pittsburgh, PA (United States)
• DOE Contract Number: AC03-86SF16038
• Assignee: Westinghouse Electric Corp. (Pittsburgh, PA)
• Patent Number(s): US 4966747
• OSTI ID: 867577
• Country of Publication: United States
• Language: English

Related Subjects

hydro-ball
in-core
instrumentation
method
operation
employs
detector
strings
comprising
wire
radiation
sensitive
balls
affixed
diametrically
spaced
positions
therealong
opposite
tip
transportable
fluid
drag
interior
passageways
primary
coolant
caused
flow
selectively
directions
transporting
stored
exterior
chamber
inserted
thimbles
fuel
rod
assemblies
pressure
vessel
return
contact
disconnectable
joints
sections
facilitate
assembly
disassembly
refueling
routine
maintenance
operations
pass
bend
radius
minimizing
space
requirements
connections
concomitantly
containment
structure
improved
mapping
significant
reduction
potential
exposure
personnel
provided
top
head
bottom
penetration
embodiments
disclosed
opposite direction
significant reduction
bottom head
opposite directions
containment structure
pressure vessel
fuel rod
primary coolant
rod assemblies
radiation sensitive
spaced positions
improved radiation
facilitate assembly
in-core instrumentation
hydro-ball in-core
positions therealong
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