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A steam engine will have the steam supply to the cylinder shut off once the piston has traveled _____ of its stroke.

1/4 to 1/3

75% to 90%

15% to 20%

55% to 65%

90% to 95%
1/4 to 1/3
A steam engine piston:

Moves fastest at the end of its stroke.

Produces the most force at the end of its strke.
o
Is lubricated with crankcase oil by the splash method.

Moves fastest at the mid-point of its stroke.

Needs no lubrication.
Moves fastest at the mid-point of its stroke.
(4-068-2.08) The slide valve of a steam engine is designed to:

Allow the piston to slide more freely.

Drain the condensate from the cylinder during warm-up.

Provide lubrication for the steam engine.

Allow steam to enter and leave the cylinder.

Prevent the engine from over speeding.
Allow steam to enter and leave the cylinder.
A routine inspection of an operating steam engine should start with:

Lubricators

Drive belts

Engine speed

Steam temperature

Steam quality
Lubricators
(4-068-1.03) Despite their size and complexity, steam plants are widely used because:

Of their low emissions of pollutants.

They are easily located in an urban environment.

They can be run by untrained personnel.

They require minimal amounts of water.

They can burn solid fuels such as coal and wood.
They can burn solid fuels such as coal and wood.
One of the first ways to detect a fault in a reciprocating steam engine is by:

Monitoring changes in its sound.

Observing temperature indication.

Determining its performance efficiency.

Monitoring its oil consumption.

Monitoring changes in smell.
Monitoring changes in its sound.
(4-068-2.03) A steam engine's crosshead:


Imparts angular motion to the piston rod.

Converts linear motion of the piston rod into angular motion.

Imparts linear motion to the connecting rod.

Does not require any lubrication.

Is often called thegudgeon
Converts linear motion of the piston rod into angular motion.
Which of the following is a prime mover?

An electric generator

A gas turbine

A centrifugal pump

An air compressor

A boiler
A gas turbine
The term "prime mover" refers to:


All heat engines

A device that uses a source of energy to produce mechanical motion

Electric motors only

Steam and gas turbines only

Thermal generating stations
A device that uses a source of energy to produce mechanical motion
The reciprocating motion of a steam engine is converted to rotary motion:

At the end of the piston stroke

In the steam cylinder

By the camshaft

At the crankshaft

By the valve gear
At the crankshaft
Connecting rods on a steam engine:

Convert reciprocating motion to rotary motion.

Are used to move the slide valve.

Are only needed on vertical engines.

Are used to connect the piston to the slide valve.

Connects the inlet valve to the discharge valve.
Convert reciprocating motion to rotary motion.
A "heat engine" is an operating cycle that uses a fluid to convert:


Thermal energy to chemical energy

Chemical energy to mechanical energy

Thermal energy to electrical energy

Mechanical energy to electrical energy

Thermal energy to mechanical energy
Thermal energy to mechanical energy
Large power production plants tend to be of the thermal type because they can burn solid fuels and:

They are the least expensive to build.

The noise level is much less than internal combustion engines.

The heat cycle they use is the most efficient.

Solid fuels are the most plentiful and the cheapest.

They require the least amount of manpower.
The heat cycle they use is the most efficient.
When possible, a wise and simple method of checking the bearings of operating equipment involves:

Checking the oil quality leaving each bearing.

Checking the oil quantity leaving each bearing.

Getting accustomed to normal operating temperature and vibration by feel.

Noticing the normal operating scent of each bearing.

Observing the bearing temperature on a thermometer.
Getting accustomed to normal operating temperature and vibration by feel.
Shaft sealing carbon glands are:

Lubricated by the main oil pump

Limited to a temperature of 250°C

Replaced monthly due to erosion

Self-lubricating

Sprayed with Monel
Self-lubricating
Two of the more important methods of classifying a steam turbine are by the stationary steam passages and the:

Casing passages

Exhaust passages

Rotor passages

Inlet passages

Oil passages
Rotor passages
Impulse turbines:

Are only used with low pressure steam.

Require large thrust bearings.

Were invented by Parsons.

Have large pressure drops across the huckets.

Have blades with the same steam inlet and outlet angles.
Have blades with the same steam inlet and outlet angles.
In theory, impulse turbines:

Have a velocity drop through the nozzle.

Have no pressure drop through the moving blades.

Use only low-pressure steam.

Develop the most torque of all turbines.

Require large thrust bearings.
Have no pressure drop through the moving blades.
(4-069-5.01) Steam turbine governors:

Prevent the turbine from over speeding.

Regulate the speed of the turbine automatically.

Should be checked annually by the boiler inspector.

Are driven by the generator shaft.

Are not required for reaction turbines.
Regulate the speed of the turbine automatically.
Steam turbine lubrication oil:

Can be used to operate the turbine governor.

Must be water soluble.

Lubricates the dummy piston.

Contaminates the condensate of condensing turbines.

Lubricates the labyrinth gland.
Can be used to operate the turbine governor.
he shafts of high output, high temperature steam turbines are usually sealed by using:

Compressed air seals

Carbon rings

Packing rings

Oil sealed glands

Labyrinth glands
Labyrinth glands
In a reaction turbine the steam pressure _____ in passing through moving blades, as well as through stationary nozzles or blades.

Increases

Decreases

Remains constant

Accelerates

Fluctuates
Decreases
A steam turbine should trip or shut down when normal operating speed is exceeded by:

250 RPM

3 to 5%

50 RPM

10 to 15%

25 RPM
10 to 15%
(4-069-5.03) The hand wheel used to adjust the turbine speed on the governor is known as the:

Controller

Pilot

Throttle

Speeder

Tachometer
Speeder
Blades, also called _____, form the steam flow passages in impulse turbines.

Buckets

Cylinders

Ports

Pipes

Diaphragms
Buckets
The purpose of turbine glands is to prevent:

Water from entering the turbine.

Steam from entering the turbine.

Steam escaping from the turbine.

Steam from entering the lubrication system.

Oil from entering the turbine.
Steam escaping from the turbine.
A turbine overspeed trip:

Trips the turbine if it is overloaded.

Is installed on all turbines.

Can be adjusted according to the load demand.

Is regulated by exhaust pressure.

Disconnects the turbine load if the turbine overspeeds.
Is installed on all turbines.
he exhaust from a steam turbine can often supply a process with steam because:

Processes usually require lower pressure, superheated steam.

Processes do not use steam at boiler pressure.

The steam will be at a temperature above the initial temperature.

Turbine exhaust steam is free of oil.

Turbine exhaust steam is dry and saturated.
Turbine exhaust steam is free of oil.
(4-069-2.06) Turbines often have segmental carbon ring sealing glands that are held in place by:

Set screws

Woodruff keys

Drive screws

Springs

Thrust runners
Springs
Natural draft cooling towers are divided into:

Dry and wet types

Closed and semi closed types

Atmospheric towers and chimney towers

Filled and unfilled types

Open and filled types
Atmospheric towers and chimney towers
Air flow in a natural draft cooling tower is dependent upon the:

Speed of the cooling fan.

Volume of water flowing through.

Partial pressure exerted above the surface of the sump.

Differences in the temperature of the air leaving and entering the cooling tower.

Wind direction.
Differences in the temperature of the air leaving and entering the cooling tower.
With all other factors being equal, a counter-flow cooling tower _____________ as a cross-flow cooling tower.

Is not as tall

Has much less cooling capacity

Requires less floor space

Requires less fan power

Has a lower pressure drop
Requires less floor space
Natural draft cooling towers operate most effectively in large open spaces and:

Where wind is relatively constant.

Where relative humidity is high.

Where a large body of water is nearby.

Require a windbreak.

Must not be in direct sunlight.
Where wind is relatively constant.
(4-070-4.02) To prevent cooling tower basin water from freezing during cold weather, many units:

Are equipped with ethylene glycol antifreeze systems.

Are equipped with electric basin heaters.

Are equipped with propane burners.

Are equipped with ice defrosters.

Have salt added to the water.
Are equipped with electric basin heaters.
The principal cause of steel corrosion in cooling towers is:

Dissolved carbon dioxide

High pH

Dissolved oxygen

Low pH

Dissolved hydrogen
Dissolved oxygen
High discharge water temperature from the cooling tower could be caused by:

Low wet bulb air temperature

High wet bulb air temperature

Low dry bulb air temperature

Fine water spray in the tower

Low concentration of solids in the water
High wet bulb air temperature
Biological fouling in recirculating cooling water towers is caused by algae, _____ and bacteria growth.

Flora

Fauna

Micro-organisms

Biological

Fungi
Fungi
Organic growths also called _____ can reduce the flow rates in heat exchanger tubes and channels.

Algae

Slime

Fungi

Spores

Silt
Slime
Water contained in the air stream at the discharge of a cooling tower is removed:

With centrifugal separators

With a desiccant

Using mechanical refrigeration

By a series of baffles

With drift eliminators
With drift eliminators