Reactor Coolant System

Question 1

RCS

What is the purpose of the Reactor Coolant System?

Answer 1

1. Transfer Heat from the reactor to the S/Gs to make steam for the turbine
2. Acts a neutron moderator
3. Carries soluble boron for chemical shim and reactivity control.

shim-soluable posion that produce a spacialy uniform neutron absorbtion.

Question 2

RCS

What are the functions of the RCS?

Answer 2

1. Maintain steady state operating pressure (2235psig)
2. Prevent challenges to the RCS design pressure (2425psig) by accommodating volume changes caused by load changes.
3. Maintain hot standby conditions assuming offsite power is available.
4. Achieve the first phase of cooldown (RHR initiation)
5. Provides 1 of 3 fission product barriers

Question 3

RCS

Cool Down Limits?

Answer 3

100°F/hr

Admin limits is 95°F/hr

Question 4

RCS

Heatup rate limits?

Answer 4

60°F/hr

Admin limit is 50°F/hr

Question 5

RCS

RCS-PZR max ΔT

Answer 5

320°F (to protect the spray nozzles)

Question 6

RCS

Desgin pressure?

Answer 6

2485psig

Tech Spec limit is 2735psig

Question 7

RCS

Operating Pressure?

Answer 7

2235psig

Question 8

RCS

PRZ safteys open at what RCS pressure?

Answer 8

~2485psig

Question 9

RCS

Pressurizer PORVs open at what pressure?

Answer 9

~2335psig

Question 10

RCS

PZR spray valves start to open at what pressure?
Full open/start to close?

Answer 10

1. 2260psig going up
2. 2310psig full open (High pressure alarm)
3. 2285psig start to close when on the way down.

Question 11

RCS

High Pressure trip (2/3)

Answer 11

2376psig

Question 12

RCS

Low Pressure trip (2/3)

Answer 12

1844psig

Question 13

RCS

Low pressure alarm

Answer 13

2185psig

Question 14

RCS

T(cold) when at 100% power

Answer 14

547.6°F

Question 15

RCS

T (hot) when at 100% power

Answer 15

604.1°F

Question 16

RCS

Normal 100% ΔT? (between legs)

Answer 16

56.5°F

Question 17

RCS

Normal 100% T(avg)

Answer 17

575.9°F

Question 18

RCS

Loop 1 penetrations

Answer 18

1. Alt Charging (hot leg)
2. Normal Letdown (Cold leg)

Question 19

RCS

Loop 2 penetrations

Answer 19

1. Primary Sampling, High Head SI, RHR suction, RVLIS
2. Excess Letdown, RCS standpipe
3. Pressurizer Spray, Normal Charging

Question 20

RCS

Loop 3 penetrations

Answer 20

1. Primary Sampling, 3 PTs, Pressurizer Surge line, High Head SI, RVLIS
2. RCS Standpipe
3. Pressurizer Spray

Question 21

RCS

Common to all loops

Answer 21

1. NR RTDs (3), Wide range temp
2. Flow Indicators, RCDT connection
3. Wide Range Temp, Narrow range RTD, Si/RHR injection

Question 22

RCS

RCPs, power supplies? Oil cooled by? Flow?

Answer 22

4Kv 1,4,2 (A/B/C)
CCW
88500gpm

Question 23

RCS

RCP flywheel does what? Protects against what?

Answer 23

Adds inertia to lengthen RCP coastdown time.
(Lessens the effects of a loss of flow accident to preotect against DNB)

Question 24

RCS

RCP anti-rotation device’s purpose?

Answer 24

Prevents the large currents caused by trying to start a motor that is rotating backwards

Question 25

# RCS RCP Bearing Oil lift System Power supply? interlocks with pump?

Answer 25

* Powered from MCC-2/1/2 (A/B/C) * Must run lift pump for 2 mins before start of RCP, interlock is must have 600psig oil pressure, (white light on RTGB goes on at 650psig), must run for at least 50 seconds after pump start.

Question 26

# RCS RCP Space heaters power supply? where do you control from?

Answer 26

* MCC-8 * Control switch in Rod Drive Control room

Question 27

# RCS RCP breaker trips?

Answer 27

* 2/3 UF on 4Kv 1,2,4 will trip all RCP breakers * UV on RCP bus will trip all breakers on that bus * RCP switch to stop

Question 28

# RCS RCP seal get how many gpm from Charging

Answer 28

8 gpm

Question 29

# RCS How much gpm goes through the thermal barrier?

Answer 29

5gpm into the RCS

Question 30

# RCS What flow goes to the 1st seal?

Answer 30

3gpm

Question 31

# RCS What flow goes to the 2nd seal?

Answer 31

3gph

Question 32

# RCS How do we ensure that flow goes to the 2nd seal?

Answer 32

VCT keeps 15psig backpressure on the seal to keep flow moving to the 2nd flow

Question 33

# RCS 2nd seal discharges to?

Answer 33

Discharges into RCP standpipe (which overflows to the RCDT)

Question 34

# RCS 3rd seal gets how much flow and how?

Answer 34

10-100cc/hr, standpipe from second seal provideds backpressure. (7ft head)

Question 35

# RCS RCP shut down seal located where?

Answer 35

Between first and second seal

Question 36

# RCS When does the shut down seal actuate?

Answer 36

~280°F Allows 19gpm at total failure

Question 37

# RCS Seal injection ITS flow? Normal band? Expanded band?

Answer 37

6gpm 8-13gpm 6-20gpm

Question 38

# RCS Flow Trips (DNB) setpoints?

Answer 38

* ITS 94.68 * Above P-7 2/3 loops * Above P-8 1/3 loops * Below P-7 no trips

Question 39

# RCS Why do we have 1 HP and 3 LP taps for flow?

Answer 39

1. Minimize Loop penetrations 2. Provide conservative indication. HP tap fails you get a low flow trip, LP tap fails you have 2 others to give trip.

Question 40

# RCS RHR-750/751 interlock?

Answer 40

1. RCS pressure <445psig 2. SI-862A/B and 863A/B shut with power availiable and normal/defeat key switches in normal.