Which of the following comes earliest in the start-up se-
quence of a steam turbine?
a. Manually test the overspeed trip.
b. Open the steam inlet valve slightly to start the turbine c. Reset the overspeed trip.
rolling.
c. Reset the overspeed trip.
d. Close the casing drain valve and ensure the casing drain
steam trap remains in service.
A routine inspection of an operating steam engine should
start with:
a. checking the load on the engine. d. making sure the lubricators are feeding properly.
b. checking the boiler pressure.
c. blowing ott the steam chest drains.
d. making sure the lubricators are feeding properly.
The turbine overspeed trip:
a. Alerts the operator of excessive turbine RPM
d. Prevents the turbine from exceeding the maximum rat-
b. Opens the sentinel valve
ed speed
c. Adjusts steam flow to keep the speed at set point
d. Prevents the turbine from exceeding the maximum
rated speed
A starting device for a gas turbine
a. is also called "barring gear"
b. keeps rotating the turbine shaft until the turbine is up d. is necessary for all gas turbines
to full load
c. must be an electric motor
d. is necessary for all gas turbines
, Power Engineering - 4B7 Practice Questions and Answers Rated A
In theory, impulse turbines:
a. Develop the most torque of all turbines
c. Have no pressure drop through the moving blades
b. Can only use only low-pressure steam
c. Have no pressure drop through the moving blades
d. Have a velocity drop through the nozzle
Which of the following is a prime mover ?
a. An electric generator
b. A gas turbine
b. A gas turbine
c. An air compressor
d. A boiler
A simple gas turbine is one without reheaters or:
a. Regenerators
a. Regenerators
b. Combustors
c. Compressors
d. Starting motors
Steam turbine governors:
a. Are not required on reaction turbines
c. regulate the speed of the turbine automatically
b. Should be checked annually by the boiler inspector
c. regulate the speed of the turbine automatically
d. prevent the turbine from over speeding
The injection pump of a diesel engine is driven by:
a. A camshaft
a. A camshaft
b. The governor
c. The gudgeon pin
d. Piston action
,Some of the characteristics that make the gas turbine a
better choice over other prime movers are:
a. Increased power output at higher elevations
c. its ability to rapidly start and carry full load
b. its low fuel consumption
c. its ability to rapidly start and carry full load
d. its high thermal eflciency
e. its low power-to-weight ratio
Diesel engine governing is accomplished by:
a. modulating the pressure of the atomizing air.
b. varying the amount of fuel injected on each power b. varying the amount of fuel injected on each power
stroke stroke
c. varying the amount of air-fuel mixture drawn into the
engine when the load changes
d. varying the load on the engine
Excessive wind velocity in a natural draft cooling tower
may cause:
a. Over-cooling of the water c. High drift losses
b. Unstable sump water level
c. High drift losses
d. Damaged louvres
The output power of a gas turbine depends upon
a. the ditterence between inlet air and turbine exhaust
d. the mass of hot gas passing through the turbine per
temperature
unit time
b. the drive gear ratio between the turbine and compres-
sor
c. the temperature at the turbine inlet in Kelvin
, d. the mass of hot gas passing through the turbine per
unit time
When leached away from cooling tower
wood, it is less able to resist decay.
a. natural extractives are a. natural extractives are
b. cellulose is
c. lignin is
d. sap is
Large internal combustion engines are cooled with:
a. Condensers
d. Water jackets
b. Air cooling fins on the cylinder jackets
c. Large fans
d. Water jackets
A major diflculty encountered with a two-stroke cycle en-
gine is:
a. The lack of torque at high speed
d. Exhausting the spent gases from the cylinder
b. The diflculty in cold weather starting
c. The high speeds compared to an equivalent four-stroke
engine
d. Exhausting the spent gases from the cylinder
Biological attack on cooling tower wood attects the
a. chemicals that cement the cellulose fibres together.
d. cellulose.
b. natural extractives.
c. lignin.
d. cellulose.
An essential auxiliary in a gas turbine installation is: