RCS Flashcards
State the steam generator pressure/temperature limitation of TS 3.7.2 and the actions required if it is exceeded
• Temperature in both the RCS and secondary coolant must be >70F when pressure of either coolant in the steam generator is >200#.
o Action: Reduce steam generator pressure to <200# within 30 minutes
State the normal lineup of the reactor vessel flange leakoff system and what indications the operator has of a leak past the flange
• Normally aligned to detect leakage past the inner seal.
o Normal - Inner valve and common valve open, outer valve closed
• High temperature alarm at 200F
o Surface mounted RTD used to sound a VAS alarm
State the function of the reactor vessel head vent
- Allows for the removal of air from the vessel head region during a RCS fill and vent
- Allows for the venting of gases, such as hydrogen, during an accident
- In FR-H.1 it is used as a RCS heat removal path, i.e., bleed and feed.
State the Function of the loose parts monitoring system
- Detects impact inside the RCS and warns the operators
- Provides auto and manual recording
- Technical Requirement 3 requires it to be operable in Modes 1 & 2
State actions required by TS 3.4.1.1 if less than four reactor coolant loops are operating in modes 1 & 2
• Be in at least hot standby within 6 hours
State Basis for TS 3.4.1.1 that requires all loops to be in operation in modes 1 & 2
- Plant is designed to operate with four loops in operation
* Maintain DNBR >1.3 (SL is 1.14) during all normal operations and anticipated transients
State Actions required by mode 3 TS 3.4.1.2 if only one reactor coolant loop is in operation with the reactor trip breakers closed
• Requires 2 Loops (SG and RCP) operable with:
o 2 loops in operation when CRD system is capable of rod withdrawal
If 1 loop, Then within 1 hour – return the loop to operation or open the reactor trip breakers
o 1 loop in operation when not capable of rod withdrawal
If No loops, open the rector trip breakers and suspend operations involving a reduction in boron of the RCS, and immediately initiate actions to return the loop to operation
State Basis for the mode 3 TS 3.4.1.2 that requires two-reactor coolant loops to be operable and operating with the reactor trip breakers closed, but only one loop operating if the reactor trip breakers are open
• Two reactor coolant loops provide sufficient heat removal capability for removing core decay heat in the event of a bank withdrawal accident
State The TS basis for placing restrictions on RCP starts in modes 4 & 5 TS 3.4.1.3 & 3.4.1.4.1
• To prevent RCS over pressure transients
o Could cause cold water over pressurization event
• RCP can’t start unless the secondary water temperature is <50F above each of the RCS cold leg temperatures
Actions required in mode 4 if less than the required 2 loops are operable TS 3.4.1.3
- With less than the required loops operable immediately initiate corrective action to return loops to operable status
- With no loop in operation suspend boron reductions
State Pressure boundary leakage limit and basis
No leakage allowed
Pressure boundary leakages tend to get worse (gross failure)
State Unidentified leakage limit and basis
1 GPM
Limit amount that that can be detected from the CTMT air monitoring system and Sump
State SG leakage limit and basis
150GPD
Minimizes frequency of SG tube rupture
State Controlled leakage limit and basis
40GPM
Ensures SI flow will not be less than assumed during LOCA conditions
State Valve leakage limit and basis
0.5GPM per nominal inch of valve size up to a max of 5GPM at 2235#
State HUR and CDR limits and action for RCS
100F/HR HUR/CDR
or
A max of <= 10F in a 1 HR period during Hydrostatic testing
If any limit is violated, restore Press/Temp within 30 minutes and perform engineering evaluation
State the purpose of the Flow restrictor in the SG
minimizes pipe whip on MS line rupture,
minimizes mass flow rate during a MS line rupture
Minimizes RCS CDR
State the SG Press/temp limits of T.S. 3.7.2 and the actions required if its is exceeded
Temperature in both the RCS and Secondary coolant must be >70F when pressure of either coolant in the SG is >200#
ACTION: reduce SG pressure to <200# within 30min
Explain why VCT pressure is maintained >15#
This ensures that enough back pressure is maintained to force flow from #1 seal leak off to #2 seal
List RCP starting interlocks
1 seal DP >220# (pressure lifts seal face off of the runner)
Lift Oil Pump running
Lift oil pressure >600#
List RCP auto trips
Phase Overcurrent
Phase Differential Current
Ground Fault
Locked Rotor
Low Voltage (9600V for 1/3 sec) - trips both pumps on bus
Low Frequency (<55.5 Hz for 0.6 sec) - trips all 4 RCPs if 1 RCP on each bus experiences under frequency
State Consequences of tripping and RCP above or below P-8
Above: Rx Trip
Below: No trip but flow may reverse
State SL 2.1.1 from T.S.
In MODES 1 and 2, the combination of THERMAL POWER, Reactor Coolant System (RCS) highest loop average temperature, and pressurizer pressure shall not exceed the limits specified in the COLR; and the
following SLs shall not be exceeded:
2.1.1.1 The departure from nucleate boiling ratio (DNBR) shall be maintained greater than or equal to 1.14 for the WRB-2M DNB correlation.
2.1.1.2 The peak fuel centerline temperature shall be maintained less than 5080ºF, decreasing by 58ºF per 10,000 MWD/MTU of burnup
State SL 2.1.2 from T.S.
In MODES 1, 2, 3, 4, and 5, the RCS pressure shall be maintained less than or equal to 2735#
