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U.S. Department of Energy
Office of Scientific and Technical Information

Control rod drive hydraulic system

Patent ·
OSTI ID:7104270

This patent describes a hydraulic system for a control rod drive (CRD). It comprises a variable output-pressure CRD pump; a charging line disposed in flow communication between the CRD pump and the CRD; a purge line disposed in flow communication between the CRD pump and the CRD, and in parallel flow with the charging line; a hydraulic control unit (HCU) disposed in flow communication in the charging line between the isolation valve and the CRD and including in series flow in the charging line an HCU check valve and a normally closed scram valve, and a scram accumulator disposed therebetween for accumulating the scram fluid at the charging pressure during the charging mode; pressurizing means disposed in flow communication with the charging line downstream of the isolation valve and upstream of the scram valve; a pressure sensor operatively connected to the charging line and responsive to the scram pressure; control means operatively connected to the CRD pump, the isolation valve, and the pressure sensor, and being effective for: opening the isolation valve while the scram valve is closed when the scram pressure drops to the minimum scram pressure; and closing the isolation valve while the scram valve is closed when the scram fluid in the charging line and in the scram accumulator reaches the charging pressure.

Assignee:
General Electric Co., San Jose, CA (United States)
Patent Number(s):
A; US 5128093
Application Number:
PPN: US 7-678567
OSTI ID:
7104270
Country of Publication:
United States
Language:
English