Questions and Answers
1. There is no steam flow through the ______ tubes before the steam turbine has a steam
flow through it. Be careful not to increase boiler firing too rapidly and overheat the
reheat tubes, during startup.
a. superheater
b. economizer
c. reheater
d. boiler Correct Ans-c
2. When starting the boiler, it may be necessary to keep a flow of BFW through the
_________ tubes to prevent overheating and fouling.
a. superheater
b. economizer
c. reheater
d. boiler Correct Ans-b
3. The temperatures of the flue gas leaving the preheater must be kept above the _______
to avoid condensation.
a. flash point
b. melt point
c. dewpoint
d. ambient Correct Ans-c
4. When the boiler is shut down, the air preheater should be inspected for signs of ______.
a. wear
b. distortion
c. overheating
, d. corrosion Correct Ans-d
5. The water ________ of the economizer exit is always below that of the steam drum to
prevent steaming in the economizer.
a. Temperature
b. pressure
c. flow
d. quality Correct Ans-a
6. The water and water/steam mixture in the steam generation tubes is at _________
temperature.
a. superheat
b. critical
c. saturation
d. normal Correct Ans-c
7. The _________ increases the temperature of the steam from the H.P. turbine back up to
superheat temperature.
a. superheater
b. economizer
c. furnace
d. reheater Correct Ans-d
8. What is the main purpose of baffles in the setting of a boiler?
a. To supply strength to the setting
b. To allow hot gases to make more than one pass through a boiler
c. To produce eddy currents
d. To cause a restriction of gas flow
e. to mix the fuel gas and the combustion air for complete combustion Correct
Ans-b
, 9. Which of the following are disadvantages of using baffles in a boiler setting?
1. Eddy currents can be produced
2. Increased friction can result
3. Coal fired boilers can result in pockets of ash accumulation
4. Heat transfer is increased
a. 1,2,3,4
b. 1,2,3
c. 2,3,4 d. 2,4
d. 1,3,4 Correct Ans-b
10. In order to direct the flow of combustion gas over the tubes in a watertube boiler, it is
necessary to use _______.
a. baffles
b. deflectors
c. fans
d. preheaters Correct Ans-a
11. Baffles can be placed so as to cause the gases to flow at right angles to the tube length,
in which case they are called ________ baffles.
a. longitudinal
b. cross
c. back
d. straight Correct Ans-b
12. Baffles may be placed so as to cause the gases to flow parallel to the tubes, in which
case they are called _________ baffles.
a. longitudinal
b. cross
c. back
d. straight Correct Ans-a
13. Baffles are usually constructed of ___________ material and may be made up of
individual bricks or tiles.
a. steel