Steam Generator Flashcards
Level setpoints
U1 and U2
U1 U2
95% WR Hi alarm 95% WR
88% NR Rx trip 80.8% NR
60% NR NOL 63.7% NR
23% NR Low alrm 41.3% NR
18% NR Rx trip 36.3% NR
15% NR AMS 14% NR
Outlet nozzle purposes (4)
- Limit rapid rise in containment pressure.
- Reduce the rate of heat removal from RCS.
- Reduces the thrust forces on main steam lines.
- Limits the stress on S/G internals (Tubes/sheet)
SG tube DP limits
primary to secondary 1600 psid @650F
secondary to primary 670 psid @600F
High quality steam can be assured under following conditions:
Steady state up to 100%
5%/min ramp
10% step change
Design temp and pressure of pri and sec components.
Primary 2485# @ 650F
Secondary 1185# @ 600F
Cyclone separators for U1 use a _____ and ______ component to remove moisture.
Primary separator and
Secondary separator
Main steam flow is measure using DP across _____ and ______ with density compensation coming from _____.
SG NR tap
Main steam line
Steam pressure
Upper and lower Blowdown isolation valves auto close when _______ or _______ or _____. SD sampling valves isolate when _____ or _____. The only difference between units is that the upper blowdown isolations do not get a _____ signal.
Phase A or Lo-2 SGWL 18/36.3% U1/2 or HELB
Phase A or HELB
U2 upper does not get a HELB
Purpose of shroud
Shroud – forms the inner wall of the annular downcomer region where the Recirc Flow mixes with the incoming Feedwater Flow.
HELB actuates at _____.
134F
Unit 1 uses a _____ SG tube support system and Unit 2 uses ___.
Lattice
Quatrefoil
Unit 1 quality steam is _____ and unit 2 ____.
99.9%
99.75%
Chemicals added for chemistry control of steam generator and reasons for each:
MPA pH control
ETA Helps MPA maintain pH, MPA can foul SJAE,
What are the conditions under which Chloride Stress Corrosion will occur?
Chlorides, oxygen, susceptible metal, high temperature, existing stress
Unit ___ primary is larger by 9-10k gallons. Unit ___ secondary is larger by 20-22k gallons.
1; 2
