Nuclear Service Water(RN) Flashcards
What is the purpose of the Nuclear Service Water System?
- The Nuclear Service Water System provides an assured source of cooling during normal and emergency conditions for all heat loads in the Auxiliary and Reactor Building(except for the ice condenser).
- Supplies assured makeup water to the following:
A. Containment Valve Injection System
B. Spent Fuel Pool Cooling
C. Auxiliary Feedwater
D. Component Cooling
What is the system designator for the Nuclear Service Water System?
RN
What is the mission time for the Nuclear Service Water System?
30 days
What are the two suction sources for the Nuclear Service Water System?
- Lake Wylie
2. Standby Nuclear Service Water Pond
What is the difference between the piping from each of the suction sources for the Nuclear Service Water System?
- Water from Lake Wylie is sent to both pump its via one pipe
- Water from the SNSWP is sent to each of the two pump pits via its own pipe.
Which suction source for the Nuclear Service Water System is considered the “Ultimate Heat Sink”?
The Standby Nuclear Service Water Pond is the ultimate heat sink
What is the normal position of the Lake Wylie Intake Isolation Valves and what will cause them to automatically operate?
- The Lake Wylie Intake Isolation Valves are normally open
- The intake valves will automatically close on:
A. Train ‘A’ or ‘B’ Pit Emergency Low Pit Level
B. Unit 1 Auxiliary Shutdown Panel to LOCAL(RN-1A and RN-6B if the associated pump is running, and the signal is train related)
What is the normal position of the Standby Nuclear Service Water Pond Intake Isolation Valves and what will cause them to automatically operate?
- The Standby Nuclear Service Water Pond Intake Isolation Valves are normally closed
- The intake isolations will automatically open if:
A. Train ‘A’ or ‘B’ Pit Emergency Low Pit Level
B. Unit 1 Auxiliary Shutdown Panel to LOCAL if pump is running(train related)
What keeps debris from entering the Nuclear Service Water Intake?
A Bar Screen with 4” by 4” openings keeps debris from entering the intake
What are possible indications of intake screen blockage?
- Low Pit levels
- Intake Screen high differential pressure
- Visual observation
- Rising temperatures on RN cooled components
What is the design/purpose of the Nuclear Service Water Pumps?
- Four, one hundred percent capacity pumps
- ‘A’ train pumps take a suction from the ‘A’ Pit, ‘B’ train pumps take a suction from the ‘B’ Pit
- Upper bearing and motor coolers are cooled by RN
- RN supplies the packing flush water
What are the power supplies for the Nuclear Service Water Pumps?
1A - 1ETA
1B - 1ETB
2A - 2ETA
2B - 2ETB
What will cause an automatic start of the Nuclear Service Water Pumps?
- Safety Injection (all 4 start)
- Train related Blackout(train related pumps)
- Emergency Low Pit level (all 4 start)
What is the design/purpose of the Nuclear Service Water Discharge Vacuum Breakers?
- Allows air to enter the pump discharge piping to provide an air cushion to prevent water hammer on a pump start
- Opens at 0.2psig vacuum
What is the purpose of the Nuclear Service Water Discharge Strainers, and when are they backwashed?
- The strainers remove debris and large particles
- The discharge strainers are backwashed:
A. Greater than 6psid(automatic)
B. 24 hours(automatic)
C. Manual from the Control Room
D. Manual from local panel
What is the purpose of the Chemical addition valves, and when do they automatically isolate?
- Injects chemicals into the desired RN pit
2. Automatically close on a Safety Injection
What is the normal position of the Nuclear Service Water Supply Header Isolation Valves, and what will cause them to automatically open?
- Normally open
2. Automatically open when the associated Auxiliary Shutdown Panel placed in LOCAL
When do the Diesel Engine Jacket Water Cooler Isolation Valves automatically open?
When the associated Diesel Generator starts
What are the Nuclear Service Water Essential Header Loads?
1. Heat Exchangers: A. D/G engine jacket water cooler(KD) B. Component cooling(KC) C. Auxiliary Shutdown Panel AHU(Backup) D. Control Room Area Chiller(YC) E. Containment Spray(NS) 2. Assured Supply A. Auxiliary Feedwater(CA) B. Fuel Pool Makeup(KF, manual) C. Component Cooling(manual) D. Containment Isolation Seal Injection Water(NW) 3. Flush connection to Solid Waste System(WS)
What is the interlock between the Nuclear Service Water Pumps and the Motor Cooler Inlet Isolation Valves?
The motor cooler valves open when the pump starts, and close when the pump stops
What is the normal position of the Nuclear Service Water inlet valve to the Component Cooling heat exchanger?
Normally open
What are the two modes of operation for Nuclear Service Water outlet valve from the Component Cooling Heat Exchanger?
- KC Temp: Modulates RN flow to maintain KC outlet temperature of 87F
- Miniflow: Modulate RN flow to provide each RN pump with greater than 19,000gpm
What will cause the Nuclear Service Water Outlet Valve from the Component Cooling Heat Exchanger to fail open?
- Loss of instrument air
- Safety Injection(Unit related)
- Auxiliary Shutdown Panel to LOCAL(unit and train related)
What are the normal positions of the Containment Spray Heat Exchanger Nuclear Service Water Inlet and Outlet Valves?
They are both normally closed, and must be manually aligned
What is the normal position of the Nuclear Service Water Non-Essential Header Supply and Return Valves, and what will they automatically close on?
- Normally open
- Automatically close on:
A. Phase ‘B’ Containment Isolation Signal
B. RN Pit Emergency Low Pit Level
What is normal source of water to the Non-Essential Header?
YV, the backup(assured source) is RN
What are the loads on the Non-Essential Header?
- Auxiliary Building Supply Vent Units
- Upper Containment Vent Units
- Lower Containment Vent Units
- Incore Instrument Room Vent Units
- Reactor Coolant Pump Motor Coolers
What is the Nuclear Service Water Return from the Diesel Generators normally aligned to, and when will it swap?
- Normally aligned to the Low Pressure Service Water Discharge
- Auto swaps to the SNSWP:
A. Emergency Low Pit Level(either pit)
B. Auxiliary Shutdown Panel to LOCAL(unit and train related)
C. D/G return to the lake closes(unit and train related)This is a valve interlock, if the D/G return to SNSWP valve were to closed the return to lake valve that aligns to low pressure service water would open*
What is the Nuclear Service Water Return from the Essential and Non-Essential Headers normally aligned to, and when will it swap?
- The headers are normally aligned to Lake Wylie via the RL system
- Automatically swaps to the SNSWP on:
A. Emergency Low Pit Level(either pit)
B. Unit 1 train related Auxiliary Shutdown Panel to LOCAL(1RN-57A only closes if A train RN pump is running) - SNSWP Isolation Valves also open on a Phase ‘B’ Isolation Signal from either unit
What is the normal position of the Nuclear Service Water Return Header Crossover Isolation Valves, and when do they automatically close?
- They are normally open
- They will automatically close on:
A. Emergency Low Pit Level(either pit)
B. Unit 1 train related Auxiliary Shutdown Panel to LOCAL(1RN-53B only closes if B train pump is running)
What are the power supplies to the Nuclear Service Water Pumps?
1A - 1ETA
1B - 1ETB
2A - 2ETA
2B - 2ETB
What are the power supplies the Nuclear Service Water motor operated valves?
600V Essential Motor Control Centers
What is the power supply to the Component Cooling(KC) Heat Exchanger Outlet Throttle Valves?
EPA/EPD
What are the power supplies to the Nuclear Service Water Pit Level Instruments?
1A(B) - 1ERPA(D)
2A(B) - 2ERPA(D)
0A(B) - 1ERPA(D)
What is the power supply to the Nuclear Service Water Strainer Backwash Motor?
A - EMXQ
B - EMXR
