1|Page
OREGON BOILERS EXAM QUESTIONS AND
ANSWERS 2025
Because of the large volume of water, the boiler type
most likely to cause a boiler explosion is a ___ boiler. -
....ANSWER ....✔✔ firetube
The part of a boiler with the heat and gases of
combustion on one side and water on the other side is
known as the ___ surface. - ....ANSWER ....✔✔
heating
___ is the pressure at which the density of water and
steam are the same. - ....ANSWER ....✔✔ Critical
pressure
An electric boiler produces heat using electrodes or ___.
- ....ANSWER ....✔✔ resistance coils
Boiler horsepower (BHP) is the amount of energy equal
to the evaporation of ___ lb/hr of water from and at a
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feedwater temperature of 212°F. - ....ANSWER
....✔✔ 34.5
A high pressure steam boiler operates at a steam
pressure of more than ___ psi. - ....ANSWER ....✔✔
15
A ___ results in a higher boiling point for water in a
boiler. - ....ANSWER ....✔✔ higher steam pressure
A(n) ___ is a boiler that uses heat recovered from a hot
gas stream, such as hot exhaust gases from a kiln or
from a gas turbine. - ....ANSWER ....✔✔ heat
recovery steam generator (HRSG)
A ___ is the lowest part of the water side of a
watertube boiler. - ....ANSWER ....✔✔ mud drum
By increasing the number of passes and the number of
fire tubes, water can absorb more heat and ___
increases. - ....ANSWER ....✔✔ thermal efficiency
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The steam drum of watertube boilers is dished (concave)
to eliminate the need for ___. - ....ANSWER ....✔✔
stays
___ stress occurs when two forces of equal intensity act
from opposite directions and push toward the center of
an object. - ....ANSWER ....✔✔ Compressive
___ are used to direct the gases of combustion so that
they come in close contact with the boiler heating
surface. - ....ANSWER ....✔✔ Baffles
A ___ is a set of tubes that is placed in the furnace area
of watertube boilers and used to increase the heating
surface of boilers and the service life of refractory. -
....ANSWER ....✔✔ waterwall
A ___ boiler comes completely assembled, with its own
pressure vessel, burner, draft fans, and fuel train. -
....ANSWER ....✔✔ package
Boiler plates and stays are subjected to ___ stress. -
....ANSWER ....✔✔ tensile
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___ are used to prevent bulging in boilers. - ....ANSWER
....✔✔ Through stays
A ___ converts the energy from the expansion of high-
pressure steam into the mechanical energy of rotation. -
....ANSWER ....✔✔ turbine
A ___ is a device that converts mechanical energy into
electrical energy. - ....ANSWER ....✔✔ generator
Cogeneration is the process of ___ and then using the
waste heat for heating buildings, providing process
heat, or further electrical generation. - ....ANSWER
....✔✔ generating electricity
Food processing plants use steam for ___,
pasteurization, and sterilization. - ....ANSWER ....✔✔
cooking
___ is the production of electricity as a result of a
conductor passing through a magnetic field. -
....ANSWER ....✔✔ Electromagnetic induction
OREGON BOILERS EXAM QUESTIONS AND
ANSWERS 2025
Because of the large volume of water, the boiler type
most likely to cause a boiler explosion is a ___ boiler. -
....ANSWER ....✔✔ firetube
The part of a boiler with the heat and gases of
combustion on one side and water on the other side is
known as the ___ surface. - ....ANSWER ....✔✔
heating
___ is the pressure at which the density of water and
steam are the same. - ....ANSWER ....✔✔ Critical
pressure
An electric boiler produces heat using electrodes or ___.
- ....ANSWER ....✔✔ resistance coils
Boiler horsepower (BHP) is the amount of energy equal
to the evaporation of ___ lb/hr of water from and at a
,2|Page
feedwater temperature of 212°F. - ....ANSWER
....✔✔ 34.5
A high pressure steam boiler operates at a steam
pressure of more than ___ psi. - ....ANSWER ....✔✔
15
A ___ results in a higher boiling point for water in a
boiler. - ....ANSWER ....✔✔ higher steam pressure
A(n) ___ is a boiler that uses heat recovered from a hot
gas stream, such as hot exhaust gases from a kiln or
from a gas turbine. - ....ANSWER ....✔✔ heat
recovery steam generator (HRSG)
A ___ is the lowest part of the water side of a
watertube boiler. - ....ANSWER ....✔✔ mud drum
By increasing the number of passes and the number of
fire tubes, water can absorb more heat and ___
increases. - ....ANSWER ....✔✔ thermal efficiency
,3|Page
The steam drum of watertube boilers is dished (concave)
to eliminate the need for ___. - ....ANSWER ....✔✔
stays
___ stress occurs when two forces of equal intensity act
from opposite directions and push toward the center of
an object. - ....ANSWER ....✔✔ Compressive
___ are used to direct the gases of combustion so that
they come in close contact with the boiler heating
surface. - ....ANSWER ....✔✔ Baffles
A ___ is a set of tubes that is placed in the furnace area
of watertube boilers and used to increase the heating
surface of boilers and the service life of refractory. -
....ANSWER ....✔✔ waterwall
A ___ boiler comes completely assembled, with its own
pressure vessel, burner, draft fans, and fuel train. -
....ANSWER ....✔✔ package
Boiler plates and stays are subjected to ___ stress. -
....ANSWER ....✔✔ tensile
, 4|Page
___ are used to prevent bulging in boilers. - ....ANSWER
....✔✔ Through stays
A ___ converts the energy from the expansion of high-
pressure steam into the mechanical energy of rotation. -
....ANSWER ....✔✔ turbine
A ___ is a device that converts mechanical energy into
electrical energy. - ....ANSWER ....✔✔ generator
Cogeneration is the process of ___ and then using the
waste heat for heating buildings, providing process
heat, or further electrical generation. - ....ANSWER
....✔✔ generating electricity
Food processing plants use steam for ___,
pasteurization, and sterilization. - ....ANSWER ....✔✔
cooking
___ is the production of electricity as a result of a
conductor passing through a magnetic field. -
....ANSWER ....✔✔ Electromagnetic induction
