Power Engineering 4B Exam Question Bank, Complete With 2000 Questions And Correct Answers, Latest
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Power Engineering 4B Exam Question Bank, Complete With 2000 Questions And Correct Answers, Latest
The steam engine will have the steam supply to the cylinder shut off once the piston has travelled:
25 to 35% of its stroke.
A prime mover is:
Steam turbine.
Best Small
A single device which c...
Power Engineering 4B Exam Question
Bank, Complete With 2000 Questions
And Correct Answers, Latest
The steam engine will have the steam supply to the cylinder shut off once the piston has
travelled:
25 to 35% of its stroke.
A prime mover is:
Steam turbine.
Best Small
A single device which converts enough will source of energy into mechanical motion is
a/an:
A prime mover.
Advantages of a steam engine include:
It is possible to change the direction of rotation without the use of gearing.
They are simple and rugged.
They have a slow rotational speed without the need for reduction gearing.
A routine daily maintenance operating steam engine should cover first and foremost.
The lubricators.
One of the first ways to detect the fault in a reciprocating engine is:
By sound.
Thinking of the steam engine and it's construction, what does eccentric mean?
Out of center.
A steam engine piston:
Has greater driving force on it at the beginning of it stroke.
Large power production plants tend to be of the thermal type because they can burn
solid fuel and:
The heat cycle they use is the most efficient.
On a steam engine, what is the purpose of a flywheel?
It dampens speed fluctuations.
It carries the engine over dead center.
What is the main advantage of using the expensive properties of steam?
Economy.
A gasoline engine is a heat engine. What is its working fluid?
Combustion gases and air mixture.
What is the purpose of a turbine thrust bearing?
To transfer turbine thrust to the load.
Shaft sealing carbon glands are:
Self lubricating
,In a turbine with a pressure lubrication system, The high-pressure oil generally goes to
the governor system. Where is the low-pressure oil led?
To the bearings.
What holds a turbines carbon packing rings axially?
Spring pressure.
Steam pressure.
For what purpose is lubricating oil required on a turbine, beside lubrication?
To carry heat away from the bearings.
In an impulse turbine:
The steam pressure is reduced in the nozzles.
Reaction turbines:
Have a pressure dropped through the moving and stationary blades.
Blades or
Buckets form the rotor flow passages in the impulse turbines.
A steam turbine should trip or shut down when normal operating speed is exceeded by:
10 to 15%.
The handwheel used to adjust the turbine speed on the governor is known as the.
Speeder.
How many basic types of turbines are there?
Two.
A large reaction turbine will have:
Steam pressure dropping through moving and stationary sections
Impulse turbines:
Have no pressure drop through the moving blades.
What do the stationary nozzles of an impulse turbine convert the thermal energy of the
steam into?
Kinetic energy.
The steam turbines exhaust can often supply the process with steam because:
It is free of oil.
When the steam pressure drop occurs in only the stationary members or components of
a turbine, the turbine is known as:
An impulse unit.
Most turbine overspeed trips operate by:
Centrifugal force.
A large reaction turbine will have:
Steam pressure dropping through moving and stationary section
Starting from the boiler and simple power generation cycle, numbering the following
components in the order in which the steam/water flows through the cycle.
One - boiler feed pump
Two - condenser
Three- turbine
Four - condensate pump
,Five- feed water heater
The great majority of turbine governors are of the
Mechanical centrifugal type
Turbine overspeed trip:
Will close the steam stop valve to the turbine
Turbine lubricating oil :
Can be used to operate the turbine governor
The turbine overspeed trip:
Prevents the turbine exceeding the maximum rated speed.
Will close the steam stop valve.
What is the purpose of the nozzles in the turbine?
To increase steam velocities
In the turbine with the pressure lubrication system, the high-pressure oil generally goes
to the governor system. Where is the low pressure oil led?
To the bearings.
The overspeed trip of a steam turbine:
Is installed on all turbines.
The purpose of the turbine glands is to prevent:
Steam escaping from the turbine.
What is the purpose of a turbine thrust bearing?
To transfer turbine thrust to the load.
When warming up a turbine:
Warm-up is done slowly.
The turbine is slowly rotated.
The warm-up must be done so that warping is prevented.
What are some advantages of the pressure system on the turbine?
Minimal maintenance required.
Reliable service.
Long bearing life.
The shrouding installed on the blading of the steam turbine serves to:
Confine the steam to the blades.
When preparing a turbine for starts, why is it warmed up slowley?
To prevent warping.
What gives wood its strength?
Cellulose.
Natural draft cooling towers operate most effectively in large open spaces and:
Where wind is relatively constant.
Water contained in the airstream at the discharge of the cooling tower is removed:
With drift eliminators.
Induced draft crossflow cooling tower.
, In cooling towers, protective films and sacrificial metals are two methods of protecting
against what?
Corrosion.
What is the purpose of the cooling tower?
To reduce the temperature of cooling water
For water temperatures up to 70°, increase of temperatures of 15 to 30° cause
corrosion rates and cooling towers:
To double.
Micro organisms require carbon to develop. Where would they get this carbon from in
the cooling tower?
From the cellulose in the wood.
Which of the following methods could be used to circulate air in a cooling tower?
Induced draft fans.
Natural draft.
Convection currents.
What could happen if the initial treatment of film forming chemicals, in the cooling tower,
is to weak?
Severe corrosion in unprotected areas is possible.
The average amount of water volume, which evaporates from a cooling tower is:
5%.
What is steel corrosion in cooling towers mainly due to?
Dissolved oxygen.
Delignification in a cooling towers wood is the result of:
Chemicals such as chlorine.
What are advantages of Venturi towers?
No fan is required.
It is quiet.
No fill is required.
Reduced maintenance requirements.
At about this water temperature, corrosion rates in cooling towers are relatively
unaffected.
70°C.
What are the two classifications of mechanical draft cooling towers?
Forced draft.
Induced draft.
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