Steam Generating/SGWLC/Blowdown

Question 1

What do the J tubes help to prevent?

Answer 1

Water Hammer when AFW initiates

Question 2

What does the flow restrictor do on each MS outlet from the SG?

Answer 2

• Provide plant protection, in case of MSLB, by decreasing steam flow rate to reduce RCS cooling rate.

Question 3

What is P-14 permissive?

Answer 3

SG Hi HI Lvl at 67% on 1 SG (2/3) FWI

SG level at 64% allows feeding

Question 4

What will P-14 permissive cause?

Answer 4

• Turbine Trip
• MFP Trip
• FWI

Question 5

What enables AMSAC?

Answer 5

Greater than 40% Power (C-20, 2/2 Turbine first stage Impulse pressure)

Question 6

What generates an AMSAC signal?

Answer 6

FW flow < 25% (3/4 Feed flow)

Question 7

What will AMSAC actuate?

Answer 7

• Trips Main Turbine (30 Sec)
• Starts All 3 AFW Pumps

Question 8

What is the cooling water to the BD Hx and flash tank quenching?

Answer 8

Containment Chill Water

Question 9

What causes a Steam Line Isolation (SLI)?

Answer 9

• 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 10

What is density compensation?

Answer 10

Converts volumetric flowrate of steam to mass flowrate for input into SGWLC circuit
(Left 2 Channels)

Question 11

Where do we measure SG Level?

Answer 11

SG Downcomer

Question 12

What is swell caused by?

Answer 12

An increase in steam flow
(which will cause an increased indication of SG lvl in the downcomer due to decreased SG pressure)

Question 13

What is shrink caused by?

Answer 13

A Reduction in steam flow
(which will cause an decreased indication of SG lvl in the downcomer due to a rise in SG pressure)

Question 14

If the controlling channel STEAM flow fails high, what will happen the FRV?

Answer 14

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

Question 15

If the controlling channel STEAM flow fails low, what will happen the FRV?

Answer 15

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

Question 16

If the controlling channel FEED flow indication fails low, what will happen the FRV?

Answer 16

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

Question 17

If the controlling channel FEED flow indication fails high, what will happen the FRV?

Answer 17

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

Question 18

What will happen if either the SG Level or Flow Controllers are lost?

Answer 18

The RU will instantly go to manual to maintain the FRV at its current position

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 less than 554°F on 2/4 loops)

Question 21

What happens on a High High SG Level of 67%?

Answer 21

1. FWI
2. Turbine Trip
3. MFP Trip

Question 22

Why does a failure of the SG Pressure input affect that SGs SF channel?

Answer 22

Because the steam flow channels are density compensated