CORE FLOOD Flashcards
Power operation with one idle RCP in each loop shall
be restricted to how long? If the reactor is not
returned to an acceptable RC pump operating
combination at the end of the time period, the reactor
shall be in what condition in the next how long?
24 hours
24 hours, then the reactor shall be in hot shutdown
condition within the next 12 hours
Each safety related snubber shall be operable.
Whenever the system protected by the snubber is
required to be OPERABLE with one or more subbers
inoperable, within 72 hours replace or restores the
inoperable snubbers to OPERABLE status and
perform engineering evaluation OR what do you have
to do ?
DECLARE THE ATTACHED SYSTEM INOPERABLE
AND FOLLOW THE APPROPRIATE ACTION
STATEMENT FOR THAT SYSTEM.
Core flood
Purpose
Floods core when RCS pressure drops below 600#
Basis for Core Flood
Need both CFT’s to completely re-flood core for hot
and cold line breaks
10CFR50.46 acceptance criteria, injects borated water
for what reasons? (5)
Limit peak cladding temp < 2200 degF
- Limit cladding oxidation < 17% of total cladding
thickness
- Limit hydrogen generated zirc-water reaction <1%
if all cladding were to react.
- Ensure a coolable core geometry
- Establish long term cooling for DHR
Minimum required for ECCS analysis for core flood
2 CF tanks
1 HPI train
1 LPI train
CF-V-1A/B
What position are the valves normally positioned?
Normally OPEN
Procedurally
During heat up position valves which way at what
pressure
During cooldown
Open valves when RCS between 650# and 700#
during heatup
Close valves when RCS between 700# and 650#
during cooldown
If valves out of position for current RCS pressure what
alarm do you get?
Alarm D-3-8
CF-V-1A/B
Power supply
Breaker normally what with EST applied
Where do you have indication as required by T.S?
1C ESV MCC
Breaker normally open
Still have indication on ES status panel as required
by T.S.
Core Flood Nozzle
Limits flow out of the reactor vessel in the event of
what?
In the event of a core flood line rupture
CF Tank sample/drain outlet isolation, CF-V-2A/B
Power supply
Closes on what ES on which train?
1A ESV MCC
CLOSE on 4# ES (A’ Train) and RTI (A’ Train)
CF Tank sample/drain CF-V-20A/B
Power supply
Interlocks (4)
1F DC (B’ train) via XCL
Interlocks (closed on ALL)
1.) Loss of DC
2.) Loss of IA
3.) 4# ES (B’ train)
4.) RTI (B’ Train)
CF tank vent to vent header, CF-V-3A/B
Power supply
Bkr normally what with EST applied?
Powered from 1A/B RW MCC
Breaker normally open, EST applied
CF tank makeup (N2 or H20) isolation CF-V-19A/B
Power supply
Interlocks
1M DC via XCR
Interlocks all closed on the following:
1.) Loss of DC
2.) Loss of IA
3.) 4# ES (A’ or B’ train)
4.) RTI (A’ or B’ train)
Operating parameters
Nitrogen Makeup:
Normal band
Psig overhead alarm D-2-7/8
Psig required by tech specs
Normal band 590-610 psig
Psig overhead alarm 585-615 psig
Psig required by tech specs 575-625
Level/Boron Makeup
Can fill tanks from MU system, but not while what?
Normal bands?
But NOT WHILE CRITICAL
Normal band: 11.35 – 11.81 ft
Boron
Normal band
Required by tech spec band
Normal band: 2350-2750 ppmB
Required by tech spec band: >2270 ppmB
Level/Boron Makeup
Temperature
Normal band
CF tank metal temperature low alarm?
Normal band >70 degF but <140 F
CF tank metal temp low alarm: 75 F
Limits and precautions
OP-TM-213-000
CF level indication will be erroneously high with the
tank depressurized. Level indication is approximately
how many inches above actual when CFT pressure is
what?
7” above actual when CFT pressure is 0
Limits and precautions
OP-TM-213-000
To avoid an invalid reading, do not allow CF-Tank level
to exceed how many ft? exceeding that limit will result
in filling the CF tank what with water?
Exceeding 14ft
Filling the CF tank reference leg with water
During startup, the core flood tank isolation valves
must be in what position? When the reactor coolant
system pressure rises to what pressure? But is less
than what pressure?
Core flood tank isolation valves must be OPENED
when reactor coolant system pressure rises to 650
psig, but is less than 700 psig.
During normal reactor plant cooldown, what position
do core flood tank isolation valves go to when reactor
coolant pressure drops to less than what pressure but
greater than what pressure?
Core flood tank isolation valves CLOSED
Normal vent path
Waste gas header, normal vent **
Normal fill path
Fill from 4% boric acid tank**
To avoid CF tank NDTT concerns, do not all CF thank
pressure to exceed what pressure when tank metal
temp is <what temp?
140 PSIG
<70 F
If RC-RV-2 is not operable, to avoid Low Temperature
over pressure conditions (LTOP), do not allow CF tank
pressure to exceed what pressure when RCS temp is <
what temp?
590 psig
<313 F
Tech spec limit
Tank level
11.13-12.01 ft (940 +/- 30ft^3)
Tech spec limit tank pressure
N2 (470 ft^3)
600 +/- 25#
Tech spec limit
Boron
> 2270 ppm
Tech spec temp
> 70F
To avoid LOCA heat removal concerns contained
within system design basis, do not allow CF tank
temperature to exceed what temperature?
140 F
When the reactor is critical both core flood tanks
should be what at all times? And both the flood tank
discharge vales (which are which valves?) shall be in
what position at all times?
Both core flood tanks shall be operable at all time
Both core flood tank discharge valves (CF-V-1A
and 1B) shall be Open at all times
Maintain measured core flood tank boron
concentration between what concentration band?
2350 and 2750 ppm
PPC indication of core flood tank pressure should be
maintained between what pressures?
590 and 610 psig
Core flood tank level should be maintained between
what levels whenever the reactor is critical?
11.35-11.81 FT
The electrically operated discharge valves from the
CFT will assured open by what?
By administrative control and position indication
lamps on the engineered safeguards status panel
Electrically operated discharge valves from the CFT,
respective breakers for these valves shall be open and
conspicuously marked. A how much time clock is
provided to open the valve and remove power to the
valve?
A one hour time clock is provided to open the
valve and remove power to the valve
CFT vent valves CF-V-3A and CF-V-3B shall be what
position and the breakers to the CFT vent valve
motoro operators shall be tagged in what position?,
except when adjusting core flood tank level and/or
pressure?
CFT vent valves shall be closed and the breakers
to the CFT vent valve motor operators shall be
tagged open.
IF the CFT boron concentration is outside of limits, of
it the TSP baskets contain amounts of TSP outside the
limits specified by 3.3.1.3.b, or NaOH tank is outside
the limits of 3.3.1.3.b or any manual valve in the NaOH
thank discharge lines are not locked open, do what?
Restore the system to operable status within 72
hours.
If the system is not restored to meet the requirements
of specification 3.3.1 within 72 hours, the reactor shall
be placed in what condition and within how much
time?
Placed in HOT SHUTDOWN condition within six
hours
3.3.3 exceptions to 3.3.2 shall be as follows:
How many CFT’s shall be what at all times?
How many of the motor operated valves associated
with the CFT’s shall be fully open at all times?
Both CFT’s shall be OPERABLE at all times
Both the motor operated valves associated with
the CFTS shall be fully open at all times
BASES
The req’s of spec 3.3.1 assure that before the reactor can be
made critical, adequate engineered safety features are
operable.
1.) How many of which components are specified?
2.) However, only how many of each is necessary to
supply emergency coolant to the reactor in the
event of a loss-of-coolant accident. How many
CFT’s are required because a single CFT has
insufficient inventory to re-flood the core for hot
and cold line breaks?
1.) 2 makeup pumps, 2 decay heat removal pumps,
2 decay heat removal coolers
2.) However, only 1 of each is necessary to supply
emergency coolant to the reactor in the event
of a loss of coolant accident. But Both CFTS
are required
