In a turbine circuit, feed heaters and dearators serve to:
use up excess steam
Increase efficiency
Provide load during low demand periods
Increase turbine output
The high-pressure oil system of a typical turbine supplies oil to
Bearings
Gears
Emergency stop valves
The oil purifier
The auxillary oil pump
When starting a condensing or extraction turbine, the extraction (condensate)pump is started ______ the _____ 1. before 2. after 3. air ejector 4. jacking oil pump 5. condenser circulating water pump
1,3
2,3
1,4
1,5
2,5
When starting an extraction turbine, sealing steam to the turbine glands is admitted _____ is put in operation
Before the extraction pump
Before the condenser circulating water pump
After the air ejector
After the extraction pump
After the throttle valve is open
The jacking oil pump is shut down when the turbine reaches a speed of approximately _____ rpm
5-10
20-30
40-50
50-60
0-80
The overspeed trip a turbine is usually set to trip the mechanism when it reaches ____ of operating speed
100%
105%
110%
115%
120%
Lubricating oil for a turbine may: 1. Lubricate bearings 2. Lubricate gears. 3. Operate throttle valves. 4. Be supplied to a governor.
1,2
3,4
1,2,3
2,3,4
1,2,3,4
When a hydraulic overspeed trip operates 1. High pressure oil forces the main steam valve shut. 2. High pressure oil supply is shut off 3. The stop valve oil cylinder drain is closed. 4. The stop valve oil cylinder drain is opened 5. A spring closes the main steam valve 6. The pilot drain is closed
1,3,6
2,4,5
3,4,6
2,4,6
3,4,5
The warm up time required of a turbine is dependant on
How quickly the turbine is required
The manufacturers instructions
The size of the turbine
The type of turbine
Whether the steam is dry or wet
Overload governing is used on ______ turbines
Small
Impulse
Low pressure
Reaction
Impulse and Reaction
