RCP Flashcards
Emergency core cooling systems
Maintenance or testing
how long if system is not restored within 72
hours
If the system is not restored to meet the
requirements of spec 3.3.1 within 72 hours, the
reactor shall be placed in a HOT SHUTDOWN
condition within 6 hours.
ES actuation
Mu-v-2a/b
Take suction from BWST
Normal makeup get isolated
Muv 18, 36, 37 go closed
16 abcd go open
25 and 26 open
RCP’s
Limits and precautions
To reduce breakaway torque and magnitude
of starting current, do NOT do secure what
until RC pump is operating at what speed?
Do not secure high pressure oil lift pumps until RC
pump is operating at full speed
Limits and precautions
To avoid insulation breakdown, Limit pump
motor starts to how many from what
temperature, allowing the motor to coast to
rest between starts, or how many starts if at
operating temp. after those how many mins
running or how many mins w/ motor stopped
must elapse
Limit pump motor starts to 3 from ambient temp
allowing the motor to coast to rest between starts
OR
2 starts if at operating temp
Thereafter 20 mins running or 40 mins w/ motor
stopped must elapse.
Back stop pumps should be started prior to
what, and what pumps started immediately
following what?
Why do we verify auto start or start pump?
Backstop pumps should be started prior to RCP
S/D + lift pumps started immediately following
RCP trip/shutdown.
Verify auto start or start pump to avoid bearing
damage
Establish seal injection prior to opening
what?
CBO (maintain SI flow at all time w/ CBO for
preventing debris
Seal injection flow required to all RCP’s when
temp >what? And pressure >what? In loss of
SI mode?
SI flow required to all RCP’s when temp >190F
and pressure >100# in loss of SI mode
Tech Specs
3.1.1.1 reactor coolant pumps:
Power operating with how many idle RCP in
EACH loop shall be restricted to how many
hours? If not restored, RX shall be in what
within how many hours? (power<what
percentage?)
Power operation with 1 idle RCP in eACh leap
shall be restricted to 24 hours. If not restored, Rx
shall be in HSD within 12 hours. (power <49%)
Reactor coolant pump (RC-P-1A/B/C/D)
Power supplies
1A/1C -> A 6900 V
1B/1D -> B 6900 V
What is the prime mover for the RCP?
Impeller
RC sub component
Thermal barrier
If SI is lost, ICCW (~40 gpm) via thermal
barrier cools what?
RC leaking to area
RCP sub component
Labyrinth seal
Purpose
Limits flow of seal water into primary to 5 gpm and
restricts RCS flow to RCP if seal injection is lost
Rcp sub component
Flywheel
Purpose and how many each RCP has and
why?
Adds significant mass to RCP motor to increase
coastdown time. RC-P-1A/B/D have two , RC-P-
1C has one. Ensures adequate flow (coast down)
folowoing loss of all 4 RCPs for protection form
DNB
Does RC-P-1C have a backstop oil pump and
why?
NO, it has a different clutch assembly
High pressure Oil life system:
Purpose and why
Forces oil between thrust bearing rubbing
surfaces to reduce breakaway torque. This
prevents motor overload and damage to bearing
babbitt surfaces.
High pressure oil life system
Power supplies
A/C -> 1A ES MCC
B/D -> 1B ES MCC
High pressure oil lift system:
Operation when its started and stopped
Started before starting RCP
Stopped AFTER RCP is running
High pressure oil lift system:
Auto start:
27/86 lockout
Auto starts: starts on RCP bkr trip
27/86 lockout: RC-P-2A/C-1 -> on A ES, RC-P-
2B/D-1 on B ES
Reactor coolant pump startup requirements
Purpose and RCS temp to start 4th RCP
RCP startup req’s for normal ops are minimum
RCS pressures and temps to ensure NPSH and
verification that supporting a systems are lined up
and startup interlocks are met.
RCS must be >407F to start 4th RCP
Reactor coolant pump startup requirements
(score)
Seals -> SI >22gpm AND Thermal Barrier Cooling
>550gpm
Cooling ->NS Pumps 52 Bkr Contacts
Oil -> Upper Bearing (>-1”), Lower Bearing (>-2” or >0
for RC-P-1C), Backstop Flow (>0.4gpm), Lift Pressure
(>1000# or >610# for RC-P-1C)
Reactor ->Less than 30% Power (prevents cold
water/positive react.)
Electrical -> Motor Starting UV <6.62kV
Reactor Coolant Pump AUTO Trips:
(soups)
Short Circuit > 7478 amps
Overcurrent > 1273 amps
Undervoltage <6.15kv for 5.18 sec
Phase Differential of 5 Amps between phases
Seal Injection (<22 gpm) AND ICCW <550 gpm for
10 seconds
Conditions Requiring RCP Trip
What level loss of SI and ICCW
Total loss
Conditions Requiring RCP Trip
Loss of what cooling flow?
Loss of NS cooling flow
Conditions Requiring RCP Trip
Pump radial bearing temp >what
temp?
> 225F
Conditions Requiring RCP Trip
Time critical action one and what do
you have to do?
Loss of 25 SCM IAW EOP-010 Rule 1
-> time critical action within 1
minute. Verify SCM meter during
initial rx trip b/c temp transmitter is
slow to respond but pressure drops
INSTANTLY
Conditions Requiring RCP Trip
CBO > what temp?
> 260F
Conditions Requiring RCP Trip
Failure/serious degradation of how
many seals w/ differential pressure of
what on any seal?
2 seals w/ 1700 psid on any seal
Conditions Requiring RCP Trip
Pump vibes > how many mils w/ how
many pumps or how many mils w/
single pumps
Pump vibes >20 mils w/ 4 pumps OR
30 mils w/ single pumps
Motor vibes > how many mils
Motor vibes >4 mils
Conditions Requiring RCP Trip
Motor thrust bearing temps >what
temp
Motor winding temp > what temp
Motor bearing uppor lower guide
temps >what temp?
Motor bearing upper or lower guide
temps >185F (195F for C)
Motor thrust bearing temp >200F
(195F for C)
Motor winding temp >302F (150C)
Flowserve N-9000 shaft seals:
Differential pressure withstand?
Each stage can withstand full
system pressure. Even pressure
distribution is an indication of seal
health
Flowserve N-9000 shaft seals:
Monitoring parameters (3)
1.) Seal delta P: stage delta P is the critical
parameter to determine seal failure. Hi-
2 PPC deltaP alarm is 1700 psid which
requires manual pump shutdown
2.) CBO temp: if CBO temp>260F, then
place the RCP in standby
3.) CBO Flow: 1.0 gpm low flow cut out
during SD/HU when RCS<NOP
Extended loss of AC power (ELAP)
Seals limit RCS losses with loss of all
seal cooling
New seals provide margin to allow for
flex RCS inventory
Flex strategy provides for closures of
MU-V-33A-D to stop CBO flow
Extended Loss of AC POWER (ELAP)
After six hours, CBO will be isolated
and rCS temp will be reduced at 30F/hr
IN the event of an extended loss of aC
power (ELAP), RCS water temp at the
rcp will be maintained at less than
560F for less than 6 hours with CBO
un-isolated.
Cavity Venting
Purpose
To ensure adequate gas pressure
in the RCP cavity to allow
draining the cold legs without
reducing RCS water level below
the RCP spillover elevation
(siphoning effect).
What temperature does the motor
overload (amber) light come in at?
780 amps
Nuke services RCP cooling:
Names of the coolers and their gpm (5)
1.)Lower oil cooler 8 gpm
2.)#1 upper oil cooler 60gpm
3.)#2 upper oil cooler 60 gpm
4.)Motor air cooler 80 gpm
5.)RC-P-1C upper cooler (one)
152 gpm
Pressure after radial bearing in RC
pump?
~2145
Pressure after seal 1
~1430
Pressure after seal 2?
~715
No 3 leak off flow?
.05 gpm
CBO flow?
~2.4 gpm
RCP system operation:
Loss of DC
High side 7kv feeder bkrs -> E DC (A DC)
low side 7kv motor bkrs -> F DC (B DC)
If you lose E dc, must trip RC pumps w/
control switch, if you lose F DC, must trip
7kv feeder buses (panel right)
RCP system operation:
Loss of seal cooling (time associated)
No challenge to RCP seal integrity for at
least 30 mins after loss of sealing cooling
Seal function
Leakage is < what flow with all seals intact and CBO
open?
<2.5 gpm
How much is CBO flow total with how much
differential pressure evenly across the seals?
2.5 gpm with 710 psid evenly across the
seals
How much seal leakage past #3 seal to RCDT?
.05 gpm
On 2 seal failures, either 1 partial and 1 full or 2 full
failures (3)
1.) Dp on one seal will exceed 1700# HI-2
alarm
2.) Requires RCP manual S/D IAW
procedure
3.) Should actuate a high CBO flow alarm
>3.5 gpm
Abeyance seal
What steam flow equivalent will cause this seal to
actuate to the closed position to terminate leakage
flow?
Steam flow equivalent to 4 gpm of liquid water (or an
estimated low temp liquid flow of 30 gpm)
Back stop (anti rotation) device
What does RCP-1A/B/D use to prevent reverse
rotation?
Marland clutch
Back stop (anti-rotation) device
What does RC-P-1C use to prevent rotation?
Ratchet and pawl assembly
(doesn’t require oil flow to function, allowed removal
of backstop oil pumps)
High pressure lift system
Purpose
Forces oil between the thrust bearing rubbing
surfaces to reduce breakaway torque
RC-P-2A/B/C/D (AC) auto starts when?
Power supply
27/86 condition?
When RCP bkr opens/trips
A/C 1A ES MCC, B/D 1B ES MCC
27/86 LO ES with UV
RC-P-2A/B/C/D (DC)
When does it auto start? Power supply
Low oil pressure 1000# and RCP bkr opens/trips (both)
A/C powered from 1C DC, B/D from 1D DC
Back stop oil pumps (RC-P-3A/B/D) (C doesn’t have)
Power supply
3A/B/D1 powered from 1A RX plant MCC
3A/B/D2 from 1B Rx plant MCC
RCP pump/motor vibe setpoints
Alert and danger for both
Pump: 15 mils alert, 20 mils danger
Motor: 3 mils alert, 7 mils danger
RCP amps you should know
Normal amps
Locked rotor
On motor overload amber light
Normal 678 (C 693)
Locked rotor 3800 (C 4000)
On motor overload amber light 780 amps
Do NOT start RCP unless RCS pressure is what band
and cooling flow through the RCP bearings is what
gpm?
To ensure a minimum cooling flow through the RCP
bearings of 0.8 GPM, do not start the RCP unless RCS
pressure is 220-225 psig.
Interlocks will only start a lift oil pump on RCP breaker
trip/open. It is necessary to start a what and a what as
an RCP is secured.
Necessary to start a backstop (except C) and a lift oil
pump as an RCP is secured
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
Core flood Purpose
Floods core when RCS pressure drops below 600#
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
