Control Oil

Question 1

What is the purpose of the CO system?

Answer 1

provide pressurized hyd fluid for operation of the main steam control valves, stop valves, combined intermediate valves and electrohydraulic control system

Question 2

When is the transfer filtering pump used?

Answer 2

when fluid reservoir is being filled or drained of for bypass filtering of reservoir fluid when the hydraulic pumps are shut down

Question 3

What is the cooling water for control oil hyd coolers?

Answer 3

TC

Question 4

what system powers main hyd pumps?

Answer 4

NG

Question 5

What happens if power is lost to hydraulic pumps?

Answer 5

turbine will trip on low oil pressure

Question 6

What system powers the filter pump motor?

Answer 6

NH

Question 7

What does NN do for the CO system?

Answer 7

power to the EHC control cabinet

Question 8

How is the hyd oil cooler affected by a loss of IA? operator actions?

Answer 8

TC control valves will fail open to the hyd oil coolers

Operator will have to throttle open the bypass around the temp control vavle and then isolate the control valve. Also goes to the CO reservoir dryer/conditioner

Question 9

What is the capacity of the hydraulic fluid reservoir?

Answer 9

800 gallons of EHC fluid

Question 10

What maintains the temp of the reservoir and how is it controlled?

Answer 10

2 electric fans operated automatically

Question 11

Why is the reservoir also equipped with temp controllers?

Answer 11

they control position of the hyd fluid coolers cooling water inlet valves such that the hydraulic fluid entering the reservoir is 115F

Question 12

Reservoir heater/fan controls, what happens when the switch is taken to START?

Answer 12

Fans will start but heaters will not energize regardless of reservoir temp

Question 13

Reservoir heater/fan controls, what happens when the switch is taken to AUTO?

Answer 13

If temp is less than 85F the fans will start and the heaters will engage.

Fans and heaters run until reservoir goes above 85F and the heater will deenergize and fans will continue to run for 10 mins after

Question 14

When reservoir heater/ fan control goes to stop what happens?

Answer 14

everything stops

Question 15

What is the capacity of the main hydraulic pumps?

Answer 15

100% each

Question 16

how do the pumps respond to system demand changes?

Answer 16

The pump will vary its stroke to meet flow demand and maintain constant pressure.

The pump will stroke to 0 delivery when dead headed.

Question 17

what is the purpose of the auxiliary pump mounted into the main pump housing?

Answer 17

takes suction on the control oil reservoir and supplies cooling and lubrication to the main pump

Question 18

What is the auto start for the standby main hydraulic pump?

Answer 18

system pressure falls below 1300psi

Question 19

where are the pumps normally operated from and where are they located?

Answer 19

control room and 100’ turbine building

Question 20

how much nitrogen is in the accumulators?

Answer 20

1000psig

Question 21

What is the purpose of the accumulators?

Answer 21

provide an immediate 200% reserve of fluid for transient flow requirements

Question 22

What is the capacity of the 2 hydraulic fluid coolers and what cools them?

Answer 22

100% capacity each
cooled by TC

Question 23

What temp range does the hydraulic fluid cooler maintain the fluid at?

Answer 23

100-125F

Question 24

What temp would sound an alarm in the control room?

Answer 24

130F high and 85F low

Question 25

What is the purpose of the air dryer? How does it perform its function?

Answer 25

remove moisture from the hyd fluid reservoir IA pushes thru the alumina alumina blue good/ pink bad

Question 26

What kind of pump is the transfer filter pump?

Answer 26

rotary positive displacement pump

Question 27

How does the transfer filter pump operate to move fluid?

Answer 27

Fluid captured between vanes in low pressure in large region and forces thru higher pressure and small area

Question 28

What uses do I have for the transfer filter pump?

Answer 28

used to provide control oil flow thru the fuller earth filters for oil purification when hyd pumps are secured. Used periodically during power unit operation for bypass filtering of fluid in the reservoir or when adding fluid to the reservoir

Question 29

What is the purpose of the fullers earth filters?

Answer 29

maintain control oil in neutral pH level by neutralizing acids and absorbing water maintain chlorine content

Question 30

What is neutralization?

Answer 30

chem reaction that stops an evens an ionic charge

Question 31

How do we prevent overpressurization of the fullers earth filters?

Answer 31

relief valves set at 75psig one relief valve is located downstream of both the hyd fluid pump and FCV-27 to ensure overpressure protection is available regardless of the pumping source

Question 32

When is the fullers earth filtering system normally in service?

Answer 32

when turbine is in service.

Question 33

What 2 important tasks are accomplished by the low pressure air purge in the stealth EHC system?

Answer 33

extracts moisture and excludes other contaminants

Question 34

how much of the rated discharge air of the membrane of the EHC system is used to transport moisture?

Answer 34

5-20%

Question 35

What is the purpose of the recirc tank

Answer 35

5 gallon tank that does batch mode purification independent of the rest of the system Used during caking after replacing fuller earth filter elements, which allows the saturation of the filter media to ensure the media will fulfill its filtering function

Question 36

What are the 4 configurations associated with CO-V204?

Answer 36

closed, discharged, recirc to fluid reservoir and discharge to recirc tank

Question 37

Where can I test the auto start of the main hydraulic fluid pumps?

Answer 37

locally at the CO skid and is coordinated with the main control room during system startup before turbine is reset

Question 38

What pressure will the turbine trip at?

Answer 38

1100psig 2 out 3 logic

Question 39

how much fluid flow is thru the fuller earth filters for continuous cleanup during normal operation?

Answer 39

5% or 2.5 gallons

Question 40

how is the system affected by loss of IA?

Answer 40

reservoir temp control valves fail open due to loss of air to the controllers CO oil reservoir conditioner dryer lose air supply EHC dryer will lose air supply