Self-actuated rate of change of pressure scram device for nuclear reactors

Patent · Tue Sep 11 00:00:00 EDT 1979

OSTI ID:5592722

Noyes, R C; Zaman, S U; Stuteville, D W

A sensor chamber having one cavity containing coolant separated by a diaphragm from another cavity containing a fixed mass of inert gas is located within a safety assembly of a liquid metal-cooled nuclear reactor. The liquid cavity is in fluid communication with the coolant outside the chamber through a flow limiting orifice. An actuating bellows in fluid communication with the gas cavity is in contact with coolant outside the chamber and is connected to a push rod, which serves as a trigger for a poison bundle relase mechanism. During slow changes in reactor coolant pressure experienced under normal operation, the diaphragm moves to equalize the gas cavity and liquid cavity pressures with the coolant pressure outside the chamber. The actuating bellows does not move because it is biased so that a threshold pressure difference is required before it will expand. Under a more rapid drop in coolant pressure, such as is associated with a loss of forced flow, the threshold is overcome and the actuating bellows will also move, thereby triggering the release mechanism to shut down the reactor. The actuating bellows may be connected to the liquid cavity rather than to the gas cavity.

• Assignee: Combustion Engineering, Inc.
• Patent Number(s): US 4167443
• Application Number: TRN: 80-002493
• OSTI ID: 5592722
• Resource Relation: Patent File Date: Filed date 30 Aug 1977
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
LMFBR TYPE REACTORS
LOSS OF FLOW
SCRAM RODS
OPERATION
BELLOWS
DESIGN
ORIFICES
PRESSURE CONTROL
TRIGGER CIRCUITS
ACCIDENTS
BREEDER REACTORS
CONTROL
CONTROL ELEMENTS
ELECTRONIC CIRCUITS
EPITHERMAL REACTORS
FAST REACTORS
FBR TYPE REACTORS
LIQUID METAL COOLED REACTORS
MECHANICAL STRUCTURES
OPENINGS
PULSE CIRCUITS
REACTOR ACCIDENTS
REACTOR COMPONENTS
REACTORS
220900* - Nuclear Reactor Technology- Reactor Safety
210500 - Power Reactors
Breeding