RCS

Question 1

What are the nominal Temperature and Pressures of the RCS?

Answer 1

2235 psig, 585F @ U1, 589F @ U2

Question 2

What are the primary components of the Reactor Vessel?

Answer 2

The Vessel, Closure Head, and 2 O-ring gaskets

Question 3

What models of SGs exist at Comanche Peak?

Answer 3

U1 has feedring SGs, U2 has pre-heater SGs

Question 4

What is the function of the RCP Oil Lift system?

Answer 4

Supplies an initial oil film during startup of the RCP; this lifts the thrust shoes away from the thrust runner

Question 5

What is the function of the RCP flywheel?

Answer 5

The flywheel increases the coastdown time of the RCP if power is lost. This allows for the continuation of coolant flow to remove decay heat in the initial stages of an accident

Question 6

What is the function of the RCP thermal barrier?

Answer 6

To limit heat transfer from the hot RCS coolant to the pump bearings/shaft via a heat exchanger cooled by CCW

Question 7

Describe the RCP seal injection flows.

Answer 7

8 gpm in from the charging pumps; 5 gpm goes past the seals into the RCS, 3 gpm goes back to the CVCS

Question 8

Describe the RCP seal leakoff rates and destination of each leakoff path.

Answer 8

Seal #1: 3 gpm, suction of CCPs
Seal #2: 3 gpd, RCDT
Seal #3: 800 cc/hr, 400 to Seal #2 leakoff, 400 to CTMT sump

Question 9

What is the purpose of the RCP Shutdown Seals?

Answer 9

To limit RCP seal leakage in the event of a loss of all seal cooling due to a Loss of AC power accident

Question 10

How many PZR heater groups are there?

Answer 10

4; 3 backup and 1 control

Question 11

How many PZR spray valves are there?

Answer 11

2

Question 12

How many PZR safety valves are there? What is their lift pressure?

Answer 12

3, 2485 psig

Question 13

Where do the PZR Safeties and ARVs discharge to?

Answer 13

Pressurizer relief tank

Question 14

What is the rupture pressure of the PRT?

Answer 14

91 psig

Question 15

What is the purpose of RVLIS?

Answer 15

To directly monitor Reactor Vessel coolant inventory

Question 16

What is the purpose of the CETs?

Answer 16

To directly monitor reactor coolant temperature at the upper core plate

Question 17

How is RCS flow measured?

Answer 17

Each loop has 3 differential pressure measurement points used to continuously monitor flow

Question 18

How is RCS cold leg flow measured?

Answer 18

2 RTDs on each loop’s cold leg

Question 19

How is RCS hot leg temperature measured?

Answer 19

2 of 4 N-16 detectors installed on each loop provide hot leg temperature indication

Question 20

What conditions are needed for natural ciculation?

Answer 20

A heat source (the core) lower than a heat sink (the SGs)