All new boilers, and boilers which have been repaired on their pressure parts, require a ___________ to be performed upon them.
a. acidizing
b. de-scaling
c. hydrostatic test
d. refractory dry out
e. soot blowing
hydrostatic test
On small boilers, a hydrostatic test is done with:
a. compressed nitrogen
b. water pressure
c. steam pressure
d. compressed air
e. acetic acid
water pressure
All traces of oil or grease must be removed from a boiler by boiling out with:
a. a suitable acid
b. hot water
c. a suitable alkali
d. a suitable solvent
e. sodium sulphite and hydrazine
a suitable alkali
After construction of the boiler setting, the refractories will contain a considerable amount of moisture. Referring to this situation, which of the following statements are correct?
1. The refractories should be dried out as fast as possible
2. The refractories should be dried slowly
3. If the refractories are dried too slowly, large cracks will appear
4. If the refractories are dried too quickly, the refractories will crack
a. 1, 3
b. 2, 4
c. 1
d. 2
e. 3
2, 4
An alkaline boil out is used on a boiler:
a. When the boiler has had oil contamination
b. Before overhauls
c. After an acid clean
d. Before returning the boiler to service after an overhaul
e. after an acid clean
When the boiler has had oil contamination
_____ storage is preferable for boilers that are out of service for an extended
period of time or in locations where freezing temperatures.
a. Dry
b. Short
c. Wet
d. Long
Dry
Moisture absorbing material should be placed on trays inside the drums to absorb moisture from the _____.
a. metal
b. tubes
c. air
d. fuel
air
Inert gas, such as nitrogen, is connected to the drum vent to maintain approximately ___ kPa. positive pressure.
a. 100
b. 35
c. 325
d. 500
35
Wet storage is used if the stand by boiler may be required for service at ______ notice.
a. Dry
b. Short
c. Wet
d. Long
Short
The ________ valve on the shutdown boiler will close when the boiler pressure drops below the header pressure
a. fuel
b. feedwater
c. header
d. nonreturn
nonreturn
When the pressure in the boiler steam drum drops to ____ kPa, the drum vents are to be opened to avoid the formation of a vacuum within the boiler.
a. 170
b. 500
c. 5
d. 1000
170
The fireside of the boiler is cleaned of all dust and soot by washing with a hot __________ solution of water.
a. acidic
b. alkaline
c. caustic
d. soapy
alkaline
The waterside of the boiler is not washed until the ________ has examined and determined the amount of sludge and scale present.
a. manager
b. worker
c. inspector
d. owner
inspector
During the high-pressure flush, the blowdown valves should be disconnected, if possible, to prevent them from getting plugged with _____.
a. water
b. rust
c. dirt
d. scale
scale
When examining the waterside surfaces, the inspector looks for signs of corrosion, pitting, and _______ of the metal.
a. bulging
b. blisters
c. cracking
d. wearing
cracking
________ is the result of dissolved air or oxygen in the feedwater.
a. Scale
b. Pitting
c. Cracking
d. Bulging
Pitting
When inspecting the fire side of the boiler, the tube and drum surfaces are examined for bulges or blisters, which indicate _____________.
a. drying
b. drafting
c. overheating
d. underheating
overheating
Refractory and brickwork of the burners, baffles, and furnace walls are checked for__________.
a. cracks
b. discoloring
c. melting
d. deterioration
deterioration
The dampers and air registers are checked for ________ and to ensure they move freely.
a. holes
b. dust
c. warpage
d. design
warpage
When performing an internal inspection of a boiler, examine the waterside through all the handhole doors for:
a. tube pitting
b. carbon deposits
c. moisture
d. process contamination
e. small salt traces
tube pitting
After an acid clean on a boiler the boiler is flushed with an alkaline solution such as:
a. Lime
b. Citrus
c. Molybdenum
d. Soda ash
e. caustic soda
Soda ash
The frequency of internal boiler cleaning depends on:
1. Feedwater quality
2. Operating schedule
3. Operating condition
4. Water treatment control
a. 1, 2, 3
b. 1, 3, 4
c. 2, 3, 4
d. 1, 2, 3, 4
e. 1, 2, 4
1, 2, 3, 4
When mechanically cleaning a boiler, the boiler must be:
a. At full load
b. At half load
c. At minimum load
d. Off the line
e. at 60% load
Off the line
____________ is carried out to remove scale that has been allowed to build up on the waterside of boilers.
a. soot blowing
b. swaging
c. pressure rolling
d. acidizing
e. expanding
acidizing
The main concern of the ________ ________ is to operate the boiler safely and efficiently.
a. power engineer
b. maintenance manager
c. boiler inspector
d. plant manager
power engineer
Heating surfaces must be _____ to ensure maximum heat transfer to the water and steam in the boiler.
a. large
b. clean
c. contacted
d. free
clean
In order for the gauge glass to show the correct level, all connections to the gauge glass and the water column, must be _________ to ensure they are clear and free from obstructions.
a. tight
b. purged
c. blowndown
d. unblocked
blowndown
If the water column is fitted with high and low water alarms, then their operation is checked at regular intervals.
a. True
b. False
true
The boiler operators must be familiar with the __________ for starting up the standby feed pump and stopping the in service pump.
a. procedure
b. schedule
c. boiler
d. deaerator
procedure
In order to avoid scale formation and corrosion in the _____, the make-up water for the feedwater supply must be properly treated.
a. deaerator
b. boiler
c. furnace
d. tank
boiler
The operator must be familiar with manual operation of the _______ system, in case of a system failure.
a. generator
b. water
c. control
d. air
control
All boilers should be bottom blown, at least once a day. This is done to remove ________ that has accumulated in the bottom drum.
a. scale
b. water
c. alkanlinity
d. sludge
sludge
The operator should make a general inspection of the entire plant every _____ hours.
a. two
b. three
c. four
d. six
two
Furnace explosions, occur when an accumulation of combustible gases ignite and explode within the furnace, or gas passes of the boiler
a. True
b. False
true
_________ explosions, occur when a pressure part of the boiler, such as the steam drum, fails due to steam pressure, or a structural weakening of the metal.
a. Furnace
b. Pressure
c. Gas
d. Water
Pressure
List five of the most common causes of furnace explosions:
1. Failure to purge the furnace adequately before start-up
2. Admission of fuel to main burner before pilot flame or other ignition source is established.
3. Loss of ID fan
4. The main flame in the furnace may get blown out.
5. Loss of FD fan
6. Attempting to light one burner off other burners, in operation.
7. Incorrect amount of air supplied to the burner can resulting in incomplete combustion.
a. 3, 4, 5, 6, 7
b. 1, 2, 3, 6, 7
c. 1, 2, 3, 4, 5
d. 1, 2, 4, 6, 7
e. 1, 3, 4, 6, 7
1, 2, 4, 6, 7
List the two major causes of pressure explosions:
1. Pressure in excess of that for which the boiler was designed
2. Poor quality feedwater
3. Weakening of the material to an extent that the pressure part fails
4. Poor fuel quality
5. Non specification boiler materials
a. 1, 5
b. 1, 3
c. 1, 2
d. 1, 4
e. 3 , 5
1,3
Furnace explosions are caused by:
1. Failing to supply sufficient air to the furnace when boiler is lit
2. Failing to purge furnace properly
3. Relighting burners off hot refractory
4. Maintaining efficient ignitors and pilots
5. Installing flame sensing devices
a. 1, 2, 3
b. 2, 3, 4
c. 3, 4, 5
d. 1, 2, 5
e. 1, 4, 5
1, 2, 3
Which of the following boilers would most likely have soot blowers?
1. Gas fired boilers
2. Electric boilers
3. Coal fired boilers
4. Oil fired boilers
a. 1, 2
b. 3, 4
c. 1, 3, 4
d. 1, 2, 3, 4
e. 1, 2, 4
3, 4
During the operation of a boiler, the heating surfaces exposed to the combustion gases tend to become coated with soot and ash, which:
1. Lowers the steam pressure in the boiler
2. acts as an insulation and reduces heat transfer
3. Lowers the efficiency and capacity of the boiler
4. Increases the draft power required
a. 1, 2, 3, 4
b. 1, 2, 3
c. 1, 3, 4
d. 1, 2, 4
e. 2, 3, 4
2,3,4
The method most commonly used to remove soot and ash from boiler heating surfaces, is to blast away these deposits by means of:
1. A natural gas jet
2. A steam jet
3. A water jet
4. An air jet
a. 1, 3
b. 1, 2
c. 2, 3
d. 2, 4
e. 3, 4
2,3
Stationary type soot blowers are located in the:
1. Secondary super heater section
2. Air heater section
3. Economizer section
4. Furnace walls
a. 2, 3
b. 1, 2
c. 2, 4
d. 1, 3
e. 3, 4
2,3
The reason for having retractable soot blowers is because they:
1. Are cheaper than stationary soot blowers
2. Are used in the high temperature zones of a boiler
3. Use different cleaning mediums than stationary types
4. They are protected from high temperatures when withdrawn from the boiler
a. 1, 2, 3, 4
b. 1, 2
c. 3, 4
d. 2, 4
e. 1, 2, 3
2,4
It is important that soot blowers be adjusted, so that they do not impinge directly upon tubes or baffles because:
a. They cause too much smoke coming out of the smoke stack
b. Erosion of these parts will take place
c. It is hard on the soot blower due to too much back pressure
d. They would not clean the surface very well in this position
e. The soot blower nozzles will plug up
Erosion of these parts will take place
Which of the following conditions would indicate that the soot blowers should be operated?
1. The steam pressure is low in the boiler drum
2. High draft loss through the boiler
3. Uneconomical steam temperature
4. Uneconomical gas temperature
a. 1, 2, 3, 4
b. 1, 2, 3
c. 1, 3, 4
d. 2, 3, 4
e. 1, 2, 4
