CVCS Flashcards
1
Q
Describe LCV-459 & 460
A
- air open, fail close
- auto close on Lpzr < 17% (459-control chnl)(460 b/u)
- all three orifice valves must be closed to manually close 459/460
2
Q
Norm value regen hx
Letdown inlet
Letdown outlet
Charging inlet
Charging outlet
A
545 degrees
290
130
480
3
Q
Describe Orifice isolation valves CVCS-8149 A, B, & C
A
- air open, fail close with nitrogen b/u
- CS on VB2 and HSDP
- close on phase A
- close on Lpzr < 17%
- close if LCV-459 or 460 off open seat
- close loss of all charging
- close if LTDN hx room >/= 150 degrees (HELB)
4
Q
Describe CIV CVCS-8152
A
- air open, fail close with nitrogen b/u
- outside CNMT
- close on phase A
- close on LTDN hx room >/= 150 degrees (HELB)
5
Q
Describe HCV-133
A
- provide letdown flow via RHR when RCS d/p is too low to develop flow via CVCS
6
Q
Describe Letdown hx
A
- CCW cooled hx
- removes heat from letdown to protect resin and RCP seals
- TCV-130 maintains ~100 degrees outlet (controls CCW flow)
7
Q
Describe PCV-135
A
- air operated back pressure control valve
- maintains 350 psig downstream of orifices (prevent flashing)
- nominal set point is 58.3%
- controls pressure of RCS when solid (?)
8
Q
Describe TCV-149
A
- air operated, three way globe valve
- directs flow to demins or VCT
- fails to VCT(loss air)
- auto bypass to VCT if temp at 136 degrees
9
Q
Describe demineralizers MB (2) Cat bed (1) Deborating (2) Filters (2)
A
MB- maintain RCS chemistry(remove unwanted ions)
CB- reduce RCS pH by removing Li+ ions
DB- remove Boron when [B] so low it would take a lot of water to dilute (1-1 is MB used during forced O2)(1-2 is anion bed used to remove boron)
Ltdn filter- collects resin fines & other particulates
10
Q
How does temperature affect resin beds affinity for boron
A
- increased temp, saturated bed will release boron
- reduced temp, saturated bed will absorb more boron
boron sweats!
11
Q
Purpose of Zinc injection system
A
- reduces source term
- reduce general corrosion of primary system materials
(Materials made up of alloy 600)(pwscc) - injects downstream of seal water hx, upstream VCT
12
Q
Describe Argon injection
A
- increase source term to enhance ability to detect primary to secondary leak
- argon has short half life (1.8 hrs) and non-condensible => able to be monitored by SJAE rad monitor, injected into zinc injection line
13
Q
Describe LCV-112A
A
- air operated, fails to VCT (loss air) three way divert valve
- at set point (norm 40%) valve will divert flow from VCT to LHUTs ( mods using prop cntrlr)(LT-114)
- can be controlled manually
- trip signal from LT-112 (87% Lvct)
14
Q
Purposes of VCT
A
- NPSH for CCP’s
- maintain chemistry (H2 /N2 for O2 control)
- maintain chemistry (degas RCS)
- means to add boric acid and pri water to RCS
- back pressure on #1 Seals
15
Q
LT-112 outputs
A
- trip open signal @ 87% Lvct (ovrds mod sig)
- stop auto m/u @ 24%
- start auto m/u @ 14%
- 1/2 input to xfr CCP suction to RWST @ 5%
- ind on VB-2
