Power Engineering 3B1 Chapter 1 Questions
and Answers
Feed-water entering the boiler section first passes through the __________ section where it is
heated by the combustion gases leaving the boiler.
a. furnace
b. economizer
c. boiler drum
d. superheater Correct Ans-b
Combustion air for the burners is preheated to ______ in the air heater section by combustion
gases leaving the economizer section.
a. 150 °C
b. 100 °C
c. 350 °C
d. 500 °C Correct Ans-c
Generally two types of draft fans are used. A _____ ____ fan supplies air to the air preheater.
The preheated air (350°C) for combustion goes to the coal pulverizers and to the burners. An
______ ____ fan exhausts the combustion gases (170°C) from the air heater to the stack.
a. center mounted, external mounted
b. forced draft, induced draft
c. induced draft, forced draft
d. turbine draft, ejection draft Correct Ans-b
Natural circulation in a boiler depends upon the ___________ in the density of a column of
water and the density of a column containing a steam/water mixture.
a. amount
, b. similar
c. difference d. mass Correct Ans-c
The difference in density between water and saturated steam becomes progressively less with
increased pressure and disappears altogether at the critical pressure _______.
a. 22106 kPa
b. 15000 kPa
c. 10000 kPa
d. 25000 kPa Correct Ans-a
Steam generators operating above critical pressure are said to be ______-critical and steam
generators operating below critical pressure are classed as ____-critical.
a. sub , super
b. super, sub
c. normal, pre
d. high, low Correct Ans-b
The advantage of forced circulation in a boiler is a _________ flow in all tubes.
a. negative
b. greater
c. positive
d. mass Correct Ans-c
The disadvantages of forced circulation in a boiler are the ______ _____ of equipment, pumps,
piping, etc.
a. greater use
b. increased costs
c. higher maintenance
and Answers
Feed-water entering the boiler section first passes through the __________ section where it is
heated by the combustion gases leaving the boiler.
a. furnace
b. economizer
c. boiler drum
d. superheater Correct Ans-b
Combustion air for the burners is preheated to ______ in the air heater section by combustion
gases leaving the economizer section.
a. 150 °C
b. 100 °C
c. 350 °C
d. 500 °C Correct Ans-c
Generally two types of draft fans are used. A _____ ____ fan supplies air to the air preheater.
The preheated air (350°C) for combustion goes to the coal pulverizers and to the burners. An
______ ____ fan exhausts the combustion gases (170°C) from the air heater to the stack.
a. center mounted, external mounted
b. forced draft, induced draft
c. induced draft, forced draft
d. turbine draft, ejection draft Correct Ans-b
Natural circulation in a boiler depends upon the ___________ in the density of a column of
water and the density of a column containing a steam/water mixture.
a. amount
, b. similar
c. difference d. mass Correct Ans-c
The difference in density between water and saturated steam becomes progressively less with
increased pressure and disappears altogether at the critical pressure _______.
a. 22106 kPa
b. 15000 kPa
c. 10000 kPa
d. 25000 kPa Correct Ans-a
Steam generators operating above critical pressure are said to be ______-critical and steam
generators operating below critical pressure are classed as ____-critical.
a. sub , super
b. super, sub
c. normal, pre
d. high, low Correct Ans-b
The advantage of forced circulation in a boiler is a _________ flow in all tubes.
a. negative
b. greater
c. positive
d. mass Correct Ans-c
The disadvantages of forced circulation in a boiler are the ______ _____ of equipment, pumps,
piping, etc.
a. greater use
b. increased costs
c. higher maintenance
