RHR Flashcards
How the Residual Heat Removal
System is affected by the loss of the
Component Cooling Water System?
~Loss of CCW to RHR pump mechanical seal cooler
results in elevated seal temperatures (inability for
RHRS to remove heat from RCS).
~Loss of CCW to RHR heat exchangers results in
loss of RHR cooling capability.
What are the RHR Pump trips?
~Low-Low RWST level if individual pump suction valve (IMO-310/320) from RWST is open. ~Overload/Overcurrent. ~Loadshed.
What are the AEO actions for responding to a gas bound RHR pump?
~Vent RHR Pump Mechanical Seal Heat Exchanger
at RH-107E(W).
~Vent RHR Pump Suction at RH-138, RHR Pump
suction after loop seal.
~Vent RHR Pump Casings.
How long do you have to vent an RHR pump casings?
30min.
What is the flow paths through an RHR heat exchanger?
~RCS through the tubes.
~CCW through the shell.
What is the discharge pressure of an RHR pump?
~ 150psi.
List emergency phases for RHR.
Safety injection. Cold leg recirculating. Hot leg recirculating. RHR supplemental spray. Supply suction water to charging, safety injection, and containment spray.
List normal operations for RHR.
Outage residual heat removal.
Low temperature over pressure protection (LTOP).
Transferring water to refueling cavity.
What is suction sources for RHR?
Normal RWST.
ALT. Loop 2 Hot leg.
Recirculating phase containment recirculating sump.
What is the RHR flow path for normal cool down?
From loop 2 hot leg through pumps, heat exchangers, and crosstie, through ICM-111 to Loops 2 & 3 cold leg.
What is the RHR flow path for Alternate cool down?
From loop 2 hot leg through pumps, heat exchangers, and crosstie, through IMO-316/326 to loops 1,2,3, and 4 cold legs.
What are the RHR pump auto starts?
Safety injection.
Blackout sequence.
What is the RHR flow when refilling the reactor cavity.
From loop 2 hot leg and the RWST, through pumps, heat exchangers, and crosstie, through ICM-111 to Loops 2 & 3 cold leg.
What is the RHR flow path for reactor cavity drain down?
From loop 2 hot leg through pumps, heat exchangers, and crosstie, through RH-130 return to RWST, and through ICM-111 to Loops 2 & 3 cold leg.
What is the purpose of the RHR system?
~Remove heat energy from the core and reactor coolant during plant cool down, cold shutdown and refueling operations. ~Transfer water between the Refueling Water Storage Tank and the Refueling Cavity at the beginning and end of refueling operations. ~Provide Low Temperature Over Pressure (LTOP) protection for the RCS. ~Inject borated water into the RCS when pressure decreases below the shutoff head of the RHR pumps. ~Provide water to the SI pumps and CCP's during the recirculation phase of safety injection. ~Provide supplemental containment spray.
