Control Oil (CO) Flashcards
What is the purpose of the CO system?
Provide pressurized hydraulic fluid for the operation of:
- Main Steam Control Valves
- Main Steam Stop Valves
- Combine Intermediate Valves
- Electrohydraulic Control System
When is the Transfer Filtering Pump used?
When fluid in the reservoir is being filled or drained or for bypass filtering of reservoir fluid when the Hydraulic Pumps are shut down
What system provides cooling for the Control Oil Hydraulic coolers?
TC
What system powers the Main Hydraulic pumps?
NG
What happens if power is lost to the Hydraulic Pumps?
Turbine will trip on low oil pressure
What system powers the filter pump motor?
NH
What does NN do for the CO system?
Provides power to the EHC control cabinet
How is the Hydraulic Oil Cooler affected by a loss of IA? Operator actions?
TC control valves will fail open to the Hydraulic Oil Coolers
Operator will have to throttle open the bypass around the temperature control valve and then isolate the control valve.
Also goes to the CO Reservoir dryer/conditioner
What is the capacity of the Hydraulic Fluid Reservoir?
800 gallons of EHC fluid
What maintains the temperature of the Reservoir and how is it controlled?
Two electric-fan units, operated automatically by a thermostatic control in the power unit
Why is the Reservoir also equipped with temperature controllers?
They control position of the Hydraulic Fluid Coolers Cooling Water Inlet Valves such that the hydraulic fluid entering the reservoir is ~115F
Concerning the Reservoir Heater/Fan controls, what happens when the switch is taken to START? Auto?
Start: Fans will start, but the heaters will
not energize regardless of Reservoir
temperature
Auto: If temperature of hydraulic fluid is
<85F, the fans will start and the heaters
will energize
- Fans and heaters will continue to
operate until the temperature of the
hydraulic fluid is above 85F, at which
time the heaters will de-energize and the
fans will continue to operate for ~10
minutes to cool the heaters
What is the capacity of the Main Hydraulic Pumps?
100% capacity each
How do the pumps respond to system demand changes?
The pump will vary its stroke to meet the flow demand and maintain constant pressure
The pump will stroke to zero delivery when dead headed
What is the purpose of the auxiliary pump mounted into the main pump housing?
Takes suction on the control oil reservoir and supplies cooling and lubrication to the main pump
What would cause the standby Main Hydraulic pump to auto start?
If system pressure falls to 1300 psi