RCIC - 1.0

Question 1

What are the RCIC isolation signals?

Answer 1

Room Hi Δ T - 70 deg F 1 sec TD
Equip Room Hi Temp - 160 deg F 1 sec TD
Torus Rm Hi Temp - 128 deg F 30 min TD
Pipe chase Hi Temp - 160 deg F 30 min TD
MANual Manual Isolation PB*
Rupture Dia Press - 10 psig (150# Rupture)
Steam Line Hi D/P - 598” H2O 4 sec TD
- 50: H2O 4 sec TD
Lo Stm Sply Press - 64.5 psig w/ 4 sec TD

Question 2

Where does RCIC receive its operating steam?

Answer 2

Steam line A

Question 3

What are the normal and alternate sources for RCIC injecting water?

Answer 3

CST (normal) or suppression pool (alternate)

Question 4

What are the initiation signals for RCIC?

Answer 4

1. -38” Rx Level (1-out-of-2-taken-twice logic – has own 250VDC logic) [ NOT 1.68, NOT A SAFETY SYSTEM]
2. Manual PB (Armed and Depressed)

Question 5

What are the RCIC turbine trip signals?

Answer 5

Overspeed - 121% (5625 rpm)
Isolation signal - Auto or Man
Level 8 - +54”*
Manual Trip PB
Exh Press Hi - 50 psig
Suction Press - 20” hg VAC (2 sec TD, Jockey Pump Suction)

Question 6

What is the sequence of events that occurs on a RCIC initiation signal?

Answer 6

1. Initiation seals in for 25 seconds.
2. F022, test bypass to the CST, closes.
3. Vacuum pump starts.
4. F010, F013, F012, F046, & F045 open.(F045 does not open if F059 Turbine exh valve is shut)
5. F045 stops opening due to a limit switch on it’s actuator @ 22% (aprox 3 sec.) This brings the turbine to idle speed and allows buildup of oil pressure to the HV-4283.
6. At T-10: The F045 strokes to full open AND The Ramp Generator is initiated. The ramp generator increases to a full Turbine speed demand signal. When the ramp signal is greater than the Flow Controller signal the low signal selector will use the flow controller to control turbine speed. The low signal is direct input into turbine speed. I.e. if the low voltage gate has a 0 output, it will lower HPCI speed to 0 – like if the ramp generator output fails to 0, or if the HPCI flow controller is run down. If the flow sensor is failed low, since that inputs to the flow controller, the HPCI turbine will spin up to rated speed and trip on +54

Question 7

When does the RCIC Jockey Pump Trip?

Answer 7

Low suction pressure at a 20”HgVac (also causes a turbine trip)

Question 8

What is the indication seen on the RCIC TTV upon a turbine trip? Does anything need to be done prior to opening the valve?

Answer 8

Split indication of TTV position indicates a turbine trip. Indications must be matched closed prior to opening.

Question 9

Can you use flow control to set RCIC to 0?

Answer 9

RCIC Turbine cannot run down to zero using flow control. The Governor will reopen on lowering oil pressure maintaining an idle speed with zero flow demand.

Question 10

Where can RCIC be operated from?

Answer 10

MCR, RSP

Question 11

What is the risk of operating RCIC below 2150 RPM?

Answer 11

RCIC should not be operated below 2150RPM to prevent bearing damage or exhaust valve chatter.

Question 12

If it is desired to operate RCIC below 450 GPM, in what mode of operation should you be in and why?

Answer 12

Operation below 450 GPM(75%) should be done in manual due to flow instabilities.

Question 13

What is the normal position of the RCIC TTV?

Answer 13

4282 TTV is normally OPEN and needs oil pressure to close

Question 14

What can you control using the RCIC manual controller?

Answer 14

Manual controller controls turbine speed only

Question 15

Where does RCIC inject?

Answer 15

‘B’ Feed Line

Question 16

What occurs on a RCIC turbine trip?

Answer 16

The TTV and min flow valves close

Question 17

What is the difference between a normal RCIC turbine trip and a +54” Turbine trip?

Answer 17

Closes HV-F045 steam supply and HV-F046, cooling water supply
The following also close
1) SV-F019 minimum flow
The following open:
1) HV-F025 (in) steam line drain
2) HV-F026 (out) steam line drain
3) HV-F004 (in) vacuum tank condensate pump
discharge
4) LV-F005 (out) (allows LV-F005 to open/close
with vacuum tank water level changes)
HV-F045 and HV-F046 will reopen when RPV level decreases to -38 inches or the respective control switch is placed in the open position or the RCIC manual initiation switch is armed and depressed after level has decreased below +54”.

Question 18

When does the RCIC suction swap occur?

Answer 18

• CST level <70K.
• When F031 is F.O. then F010 will close.

Question 19

When does the RCIC suction swap occur?

Answer 19

• CST level <70K

Question 20

How does RCIC respond to RPV level after it has already initiated?

Answer 20

F045 and F046 shut on level 8 and reopen when level goes back down to -38”.

Question 21

What is the interlock for F045?

Answer 21

Cannot open if F059 is closed. (You need the steam out open to open the steam in)

Question 22

When does the VAC Breaker iso shut?

Answer 22

The F084 and F062 shut on a low supply pressure (64.5#) or Hi DW pressure (1.68#)

Question 23

Explain the min flow valve op.

Answer 23

F019 and SV-4405 open on low flow (<90 gpm) and discharge pressure >125#.