EW- Essential Cooling Water Flashcards
What must be done prior to opening the EW to NC cross tie valves? Why?
close NC non-priority heat load isolation valve so EW water doesn’t get transferred to NC system
What is the EW surge tanks low level control point?
25”
What is the purpose of the Essential Cooling Water system?
Removes heat from all essential components required for normal and emergency shutdown of the plant and rejects the heat to the Spray Pond
Upon a loss of NC, can be lined up to provide cooling water for the Fuel Pool Cooling Heat exchangers, Reactor Coolant Pumps, CEDM normal ACUs, and nuclear sample coolers and normal chillers
Intermediate barrier between RC and Essential Spray Pond to reduce possibility of radioactive leakage to the environment
What is the rated flow for a typical EW pump?
16,650 gpm at 138 ft TDH
When does the EW pump room ACU start?
when the pump starts
At what level in the EW Surge tank would the normal makeup valve automatically close to prevent feeding a leak?
14”
How does the EW system interface with the EC system?
EW removes heat from EC chillers
EC sends chilled water through the EW pump room ACU
What else starts when the EW pump starts?
EW pump room ACU (cooled by Essential Chilled Water)
What is the tech spec related to the EW system?
two EW trains must be OPERABLE
What is the normal source of makeup water to the EW? Backup sources?
Normal: Demineralized Water System (DW)
Backup: Chemical Waste System (CM) cooling water hold up tank
Safety related backup: Condensate Transfer and Storage System (CT)
If we were to drain the EWHXs, what system would I drain them to?
Oily Water System (OW)
What signals would automatically start the EW pumps?
LOP (20 seconds after EDG output breaker closes)
CSAS
SIAS
CREFAS
CRVIAS
AFAS 1 and 2
When aligning the EW system to cool the SFP HXs, what must be done prior to opening the EW valves?
closing the NC supply and return isolation valves for the HX
What electrical protection is available to the EW pump motors?
Overcurrent and ground fault protection trips that actuate an 86 lockout relay
Why do we pressurize the EW Surge tanks with nitrogen?
To prevent oxygen from getting into the system that could lead to corrosion