Steam Generating/SGWLC/Blowdown

Question 1

What do the J tubes help to prevent?

Answer 1

• Maintain ring full to minimize water Hammer when AFW initiates

Question 2

What is P-14 permissive?

Answer 2

• SG Hi HI Lvl at 67% on 1 SG (2/3)

Question 3

What will P-14 permissive cause?

Answer 3

• Turbine Trip
• MFP Trip
• FWI

Question 4

What enables AMSAC?

Answer 4

• > 40% Power (C-20, 2/2 Turbine first stage Impulse #)

Question 5

What causes an AMSAC signal?

Answer 5

• FW flow < 25% (3/4 Feed flow)

Question 6

What will AMSAC actuate?

Answer 6

• All 3 AFW Pumps

- Trips Main Turbine (30 Sec)

Question 7

Control air header pressure is lowering at a fast rate. At 80 psi, the reactor is manually tripped, and header pressure continues to lower. What will happen to the air reg valves in the BD system if pressure continues to lower?

Answer 7

• All air reg valves on BD system will isolate on loss of ctrl air
• DRV-350/352
• BD isolation valves
• BD Flow Ctrl Valves
• BD Sample Valves

Question 8

What does SGWLC maintain?

Answer 8

• SGWLC maintains SG Narrow Range level at 43.8% for all power levels.

Question 9

What is the dominant control for SG Level? ***

Answer 9

• Level Dominant (43.8%)

- Steam Generator Level overrides Feed flow/Steam Flow mismatch over time, level is a lag signal*

Question 10

What causes a Steam Line Isolation (SLI)? ***

Answer 10

• Cnt # High-High at 2.8# (2/4)
• SG # low < 500# (1/1 on 2/4 SG)
• High Stm flow with P-12 (1.42E6/1.6E6) (1/2) on 2 SG

Question 11

What is the definition of density compensation?

Answer 11

• converts volumetric flow rate of steam to mass flow rate for input into SGWLC circuit. (Left 2 Channels ctrl SG lvl)

Question 12

Where do we measure SG Level?

Answer 12

• SG Downcomer

Question 13

What is swell caused by? ***

Answer 13

• an increase in steam flow (which will cause an increased indication of SG lvl in the downcomer due to decreased SG #) (More intense boiling)

Question 14

What is shrink caused by?

Answer 14

• reduction in steam flow (which will cause an decreased indication of SG lvl in the downcomer due to a rise in SG#) (Less intense boiling)

Question 15

If the steam flow indication fails high to your flow controller, what will happen the FRV?

Answer 15

• The FRV will go open because Feed Flow will want to match Steam Flow

Question 16

If the steam flow indication fails low to your flow controller, what will happen the FRV?

Answer 16

• The FRV will go closed because Feed Flow will want to match Steam Flow

Question 17

If the feed flow indication fails low to your flow controller, what will happen the FRV?

Answer 17

• The FRV will go open because Feed Flow will want to match Steam Flow

Question 18

If the feed flow indication fails high to your flow controller, what will happen the FRV?

Answer 18

• The FRV will go closed because Feed Flow will want to match Steam Flow

Question 19

Unit 1 was operating at 100% power when a loss of main feedwater occurs to a single SG due to the failure of the controlling feedwater flow instrument.

A valid indication on the affected SG “Flows / Level / Pressure” recorder for this failure would be a rapidly lowering SG level and a?

Answer 19

• high feedwater flow indication on the feedwater flow pen.

Question 20

What will cause a FWI?

Answer 20

• SG High-High level (P-14) (67% NR 2/3 on 1 SG)
• SI
• Rx trip (P-4) with low Tavg (Tavg < 554°F on 2/4 loops)

Question 21

What is the reactor trip associated with SG Lvl Low

Answer 21

15% (U1) 26% (U2) 1/2 channels on 1/4 SGs w/ SF/FF Mismatch 0.71M (U1) 1.47M (U2) 1/2 channels on the same SG

Question 22

What happens on a SG Lvl Low-Low

Answer 22

5% (U1) 22% (U2) 2/3 channels on 1/4 SGs

• Rx Trip
• Auto start of MDAFP (1 SG)
• Auto start of TDAFP (2 SGs)

Question 23

What are the SG Pressure and Temperature TRM limits

Answer 23

Primary and secondary temps in a SG must be greater than 70 deg when the pressure of either primary or secondary is greater than 200# to prevent brittle fracture (restore in 30 mins)