CVCS: Chemical & Volume Control System

Question 1

From where does Letdown tap off of the RCS?

Answer 1

Between the #2 SG and the 2B RCP.

Question 2

What is the purpose in the Delay Coils? How do they work?

Answer 2

They allow for the decay of N-16 gammas. They are 2 12 foot long 16” diameter pipes that dramatically slow the letdown flow.

Question 3

How does CHB-UV-515 fail on a loss of air or power?

Answer 3

Closed

Question 4

How does CHA-UV-516 fail on a loss of air or power?

Answer 4

Closed

Question 5

How does CHB-UV-523 fail on a loss of air or power?

Answer 5

Closed

Question 6

What signals will automatically close CHB-UV-515?

Answer 6

SIAS

Regen Heat Exchanger Outlet temp > 413F

Question 7

What signals will automatically close CHA-UV-516?

Answer 7

CIAS

SIAS

Question 8

What signals will automatically close CHB-UV-523?

Answer 8

CIAS

LDHX outlet temp > 135F

Question 9

On what component specifically does the RHX minimize thermal shock?

Answer 9

The Reactor Vessel inlet nozzles

Question 10

Under what temperature does the RHX maintain letdown outlet temperature under normal operating conditions?

Answer 10

450F

Question 11

How do the Letdown Control Valves (CHE-LV-110P/Q) fail on a loss of air?

Answer 11

Closed

Question 12

How does a loss of NNN-D11 affect the Letdown Control Valves (CHE-LV-110P/Q)?

Answer 12

PLCS will lose power which will cause these valves to fail closed.

Question 13

How does a loss of NKN-D42 affect the Letdown Control Valves (CHE-LV-110P/Q)?

Answer 13

They will lose indication only.

Question 14

During normal operation, how many Letdown Control Valves are in service? Why?

Answer 14

One.

Sufficient differential pressure exists between the RCS and CVCS to drive the required flowrate.