Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Power 8 Gas Turbine > Section Review > Flashcards

Section Review Flashcards

1
Q

State the service flows in the gas turbine area

A

Fuel gas, instrument air, potable water, river water, hydrogen, nitrogen, CO2, service air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

State why a turbine has an over speed trip

A

To prevent damage to the turbine and generator in case of failure of the other safeguards.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

For the following problems state the causes and any corrective action required. Also state the results if corrective action is not taken.

A. Lube oil temp is slowly trending down.

B. Lube oil temp is slowly trending up.

A

A. Corrective action- Too many fans are on or control valve is open also you should see excessive bearing vibration, check other bearings, check lube oil temp in field, ccw flow/temp, and ccw valve position.

B. Corrective action- turn on fin fans and close control valve. Causes- hi bearing vibration, bearing to burn up, check other bearings, line oil temp, ccw flow/temp, and similar equipment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

State the function of the following equipment in the closed cooling water system.
A. Fin fans
B. Ccw circulation pumps

A

A. Fin fans pull air across finned tubes to cool the water
B. Circulate the cooling water through the cooling water header

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

State the equipment that is cooled by the CCW system.

A

Lube oil coolers, sample coolers, air coolers, flame detectors, turbine support legs, and hydrogen coolers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do we use for make up on the CCW system?

A

Polished water glycol mix, can use river water as back up.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe how the nitrogen pad is controlled.

A

By a regulator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

State the normal level of the CCW surge tank

A

75-80%
we run 10-15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

State the normal CCW pressure

A

60-70psi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the purpose of the auto/smart on the CCW pumps.

A

Low pressure will start the pumps in auto

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The CCW pumps are cavitating discuss cause and effects of this problem.

A

Cause- loss of suction or water is vaporizing inside pump casing.
Effect- This damages the impeller.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe actions you would take if a fin fan breaks its belt.

A

Red tag the switchgear, enter work order, locate correct belt, sign on master, and change the belt. Test before walking away to ensure it isn’t vibrating or an alignment issue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe your actions if you get a hi temp alarm on the inboard bearing on the HP boiler feed pump and the control valve is at 100%

A

Check for proper oil flow, check the CCW system isn’t leaking and working properly, turn on more fin fans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the function of each of the following gas turbine lube oil system equipment

A. Lube oil accumulator
B. Surge tank
C. Auxiliary surge tank

A

Lube oil accumulator- absorbs the shock or surge of oil durning start up/ shutdown of pumps.

Surge tank- 500 gallon tank used to reduce surge and receive oil from #2 bearing.

Aux surge tank- 250 gallon tank interconnected to the surge tank, reduces surge and receives oil from #3 bearing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

State why the following items on the lube oil system should be checked on a routine round.
Reservoir level and temp
Oil spills and leaks
Filter differential
Oil presser and temp
Pump switch positions
Cooling water and valve positions

A

Reservoir level and temp- check for proper level and temp
Oil spills or leaks- nothing is leaking or draining oil.
Filter differential- make sure filters aren’t plugged
Oil pressure and temp- it’s at normal operating temp and pressure
Pump switch positions- make sure they’ll start in emergencies.
Cooling water valve position- make sure the ccw operating properly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

State what action you would take on a low lube oil level alarm.

A

Add more oil from 8001 and check for leaks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

State what effect a high oil temp would have and what you would need to do to correct the oil temp.

A

Bearings will burn up. Make sure ccw valve is open, turn on fin fans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

State what effect a high filter differential will have and what you would need to do to correct the problem.

A

Low oil pressure due to plugged filters. Switch over to other filters and replace the plugged ones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

State the source of the 90# steam for fire protection and how it is activated.

A

LP superheater suction of HRU
Snuffing steam located on wall outside load compartment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Name the two primary hazards associated with the gas turbine fire protection system.

A

CO2- suffocation
90# steam- thermal burn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Who must be notified any time a portion of the fire protection system is taken out of service

A

Fire and security

22
Q

State the function of the fallowing valves associated with the GT fuel gas system.
A. Auto gas vent valves
B. Manual vent valve
C. Control valve
D. Fuel gas block valve

A

A. Vents durning start up shutdown
B. Depressurize the header when shutting down
C. Controls gas to burners
D. Blocks FG header

23
Q

State why the fuel gas valve to the GT should always be closed when the turbine is not running.

A

To prevent FG from entering the system and causing a fire or explosion.

24
Q

State the consequences of low fuel gas header pressure

A

Can’t start the turbine and you’ll loose load on turbines running.

25
Q

State the type of water used for the inlet air wash.

A

Polished water

26
Q

State when hearing protection is required when inside or around starting packing and why?

A

Earplugs for less then 85 decibels
Double for above 105 decibels

27
Q

State the reasons for using the compressor wash while the turbine is online

A

It cleans the first couple row of blades from debris that goes into the GT inlet filter. It also adds a few extra megawatts making the turbine more efficient.

28
Q

State the purpose of the block limit valves on the fuel gas header

A

Shut off fuel gas in the event of a fire, explosion, or leak.

29
Q

State the hazards associated with the fuel gas and distillate

A

Fuel gas is very flammable and distillate contains benzene

30
Q

Describe how the LP and HP steam evaporator levels are controlled.

A

Level is controlled by level control valves. Steam flashes out the top of the drums. Keep the tubes filled with water

31
Q

State the normal control range for the fallowing LP and HP steam evaporator perimeters.
A. Pressure
B. Level
C. Conductivity

A

Pressure- 90# and 1550#
Level- LP/HP 0 or -1 inches of water
Conductivity- LP 20-40 HP 40-50

32
Q

Describe your reaction if you heard a loud hissing noise but couldn’t see any leaks.

A

Leave the area the same way you entered it. Get a broom stick or inferred camera to locate HP leak.

33
Q

The gas turbine is at full load and all operations are normal, the LP drum level starts dropping and the level control valve is wide open. State your action to find the problem.

A

Check the pump suction strainer DP, verify control valve position, check blowdown flow, intermittent blowdown valve stuck open, level transmitter is lying, kick on second pump.

34
Q

State the function of the following pieces of equipment associated with the HRU duct burners.
Ignition transformer
Flame scanner
Color camera/monitors

A

Ignition transformers- ignition source
Flame scanners- detects flame
Color cameras/monitors- shows flame status

35
Q

State the following operating parameters:
High pressure drum PH and phosphate
Low pressure drum conductivity
Boiler feed water PH and dissolved O2

A

High pressure drum
PH 9.2-9.8
Phosphate 4-6

Low pressure drum
Conductivity- less than 100

Boiler feed water
PH 9.2-9.6
Dissolved O2 less than 10

36
Q

State the hazard of hydrogen

A

Explosion

37
Q

State the hazard of CO2

A

Suffocation

38
Q

State why the hydrogen purity in the generator is so important

A

95-98% purity to ensure a non explosive atmosphere and for more cooling capacity

39
Q

State the hazards of cross tying any flows in the generator gas supply headed

A

It’s extremely important that oxygen does not mix with hydrogen. It could cause an explosion

40
Q

Explain why the seal Oil pressure runs higher than the hydrogen pressure.

A

It keeps the hydrogen from escaping through the seals at the need of the generator motor

41
Q

State the reason why it is a good idea to check the hydrogen bank pressure each time you make a round.

A

To catch a loss of hydrogen pressure early! Swap trailers if necessary

42
Q

List the three bus identification numbers, generator, and transformer numbers.

A

Bus 81,82,83
GT 81,82,83
T 81,82,83

43
Q

State the purpose of the O breaker on each 15kv bus

A

Tie line breaker that connects the 15kv bus to the transformer

44
Q

List three hazards involved with the operation of the 15kv switchgear.

A

Arch flash, shock, electrical explosion

45
Q

List the ppe required for operating any 15kv switchgear.

A

Flash suit, hood with shield, safety glasses, flash gloves, boots, hearing protection, leg wraps

46
Q

How many techs are required when operating any 15kv switchgear?

A

2

47
Q

Why is it necessary to call power dispatch before operating any 15kv switchgear?

A

So he can adjust load and distribute power to each unit

48
Q

What is the phone number of the power dispatcher

A

2575

49
Q

Describe the purpose and operation of each of the fallowing pumps as they pertain to the seal oil system.

Main line oil pump
Aux seal oil pump
Emergency seal oil pump

A

Main line oil pump- supplies seal oil through the seal oil regulator durning normal operation.

Aux seal oil pump- AC back up pump for seal oil when the turbine is down.

Emergency seal oil pump- DC back up for seal oil when AC pump isn’t working.

50
Q

Describe the hazards associated with the loss of generator seal oil.

A

Hydrogen can leak out through the generator seals causing a fire/explosion

51
Q

State the normal control range for the seal oil differential pressure.

A

Set diff is 5-10 psi

Power 8 Gas Turbine (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions