N21 - Feedwater

Question 1

When is manual control used?

Answer 1

< 100 rpm

Question 2

When will the controller auto swap from speed auto to manual? (going down)

Answer 2

< 300 rpm

Speed sensor fail hydraulic servo slave failure

both stop valves not full open

turbine trip

Question 3

When is it preferred to swap from speed auto to feed auto?

Answer 3

2100 rpm

Question 4

When will it auto swap from feed auto back to speed auto?

Answer 4

Speed signal exceeds the HSS limit (High speed stop)

speed below LSS limit

Signal “bad quality”

signal processing circuit fail (slave module)

Question 5

When is emergency manual activated?

Answer 5

when digital control senses Hydraulic servo slave module is not in communication with the multi-functional processor

Question 6

What is a risk of emergency manual mode?

Answer 6

OVERSPEED because there is no feedback to INFI-90

Question 7

What’s the power supply for the RFPT speed control?

Answer 7

1Y99

Question 8

Where does the RFPT turbine exhaust to?

Answer 8

HP condenser

Question 9

What power levels is Start-up level control used for?

Answer 9

0-20%

Question 10

What Rx power can you go to with the loss of HP feedwater heater string?

Answer 10

95%

Question 11

What should vacuum be maintained at when the turbine is in operation? (vacuum in the RFPT lube oil tank)

Answer 11

> .5” wc or write a CR

Question 12

How many low pressure steam poppets are there?

Answer 12

7

Question 13

How many high pressure steam poppets are there?

Answer 13

1

Question 14

Which poppets are used during start up? (low or high pressure poppets)

Answer 14

High pressure

Question 15

At what reactor pressure, should you put in a feed pump?

Answer 15

400 psig

Question 16

what’s the purpose of the feedwater system? (3)

Answer 16

1. provides high pressure makeup water to make up for steam produced in the reactor during all modes of operation.
2. preheats the water to 420 deg F
3. Provides recirc flow path from common header back to hotwell. Also for heater drain clean-up

Question 17

What does the HPU control?

Answer 17

Governor

Question 18

What percent are the reactor feed pumps brought online?

Answer 18

< 8% they windmill off condensate booster pump

8% one pump

Approx 50-65% (no higher than 65), 2 pumps

Question 19

What must min/flow valve be in, to start be in to start feed pumps?

Answer 19

cascade

Question 20

What’s the purpose of the vacuum trip?

Answer 20

Protect the RFPT casing (backpressure)

Question 21

How does the min/flow valve operate? (for feed pumps)

Answer 21

Works off percentage of pump speed

Question 22

What must be running to “windmill” RFP using condensate booster pumps?

Answer 22

Oil pump

Question 23

What does nitrogen accumulator do for RFP HPU?

Answer 23

Smooth out pressure pulsations from pump piston, and provide a surge volume to maintain pressure constant

Question 24

What’s the function of the kidney loop?

Answer 24

takes suction from reservoir and recircs it through filter and heat exchanger

Question 25

What's the purpose of long cycle cleanup? (flow path)

Answer 25

Goes through condensate pumps, through CFFF, condensate booster pumps, LP heaters, Rx feed pumps, HP heaters, back to the condenser to remove stagnant, low purity water

Question 26

What's the purpose of short cycle clean up? (flow path)

Answer 26

Flow through condensate pumps, through CFFF, back to condenser through min-flow valve.

Question 27

Where does the back-up (EOP) pump get its power from?

Answer 27

"F" bus

Question 28

How does the pump suction valve (F029A/B) react to low lube oil pressure?

Answer 28

Auto closes @ <4 psig, resets @ 7 psig

Question 29

Will an HPU trip directly trip a RFPT?

Answer 29

NO

Question 30

When will Emergency DC oil pump auto start?

Answer 30

50 psig

Question 31

Where do the RFPs receive sealing water from?

Answer 31

Condensate booster pumps

Question 32

Where are the reactor feed pump suction valves operated from?

Answer 32

P175

Question 33

Where are the 2 places the RFPT can get its steam from, and when is each place used?

Answer 33

Equalizing header @ start-up 2nd stage MSR (outlet) at power

Question 34

What are the RFPT trips?

Answer 34

* SSCCORED How Many Bearings (3) S - suction love pressure <= 157 psig (15sec A, 45sec B) S- suction low flow 90% 5 min (admin manual trip) <80% 30 sec TD Auto trip C- HP control oil press low <=75 psig C- HPU header <= 1400# AND BOTH pump discharge <= 1500# (5 sec TD) O- Overspeed mechanical or electrical >= 6100 rpm R- RPV Level 9, 58" (1 sec TD) E- Exhaust vacuum low <= 16" Hg vacuum D- Deviation in Governor position/demand 20% How - High discharge pressure >= 1580 psig Many - Manual Bearings - Thrust bearing wear detector high >= 40# Turbine oil <= 4# Pump oil <= 4#

Question 35

What are the HPU trips?

Answer 35

Standby pump starts at 1500 psig > 11" from top of tank LO-LO in reservoir < 65 deg F temp in reservior

Question 36

What is the power supply to the lube oil pumps?

Answer 36

A - 13BD1 B - 12BE6

Question 37

When does the standby lube oil pump auto start?

Answer 37

< 222 psig

Question 38

What is power limited to with one feed pump? How long? How many times per year? then what must be done?

Answer 38

80%????? 3 hours 4 times per year Reduce to 78.5% power