CORRECT Answers
Question: 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 Answer: b. To allow hot gases to make more than one pass through a boiler
Question: Heat transfer is increased a. 1,2,3,4 b. 1,2,3 c. 2,3,4 d. 2,4 e. 1,3,4
Correct Answer: b. 1,2,3
Question: 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 Answer: a. baffles
Question: 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 Answer: b. cross
Question: 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 Answer: a. longitudinal
Question: Baffles are usually constructed of ___________ material and may be made up of individual
bricks or tiles. a. steel b. castable c. refractory d. insulation
Correct Answer: c. refractory
Question: Curved or streamlined baffles have the ________ of having no sharp turns to cause eddy
currents, increase friction, or form pockets for ash accumulation. a. disadvantage b. habit c. source d.
advantage
Correct Answer: d. advantage
Question: Metal fin bars are welded to adjacent tubes, forming a continuous surface and a pressure- tight
wall, this is referred to as a welded fin tube wall or a ________ wall. a. solid b. membrane c. screen tube d.
tangent tube
Correct Answer: b. membrane
Question: A wall suitable for severe service, here the tubes are side by side and touching each other, this is
called a ________ wall. a. solid b. membrane c. screen tube d. tangent tube
Correct Answer: d. tangent tube
Question: Flat plates or studs are welded to each side of the tubes, this is called a _______ wall. a. flat stud
tube b. screen tube c. tangent tube d. membrane
Correct Answer: a. flat stud tube
Question: In the watertube boiler, water cooling of the furnace is achieved by arranging tubes to form all or
part of the furnace walls. Which of the following refers to this type of construction? Tangent tube wall
Fin-welded tubes Tube and brick wall Flat-stud tube wall 1,2,3,4 2,3 2,3,4 1,2 1,3
, Correct Answer: a. 1,2,3,4
Question: Steam produced from water in a boiler is at saturation temperature and usually contains a certain
amount of moisture. The purpose of the superheater is
Correct Answer: To save on chemical make-up to the boiler That any moisture present in the steam will be
evaporated Is to help protect the turbine blades from erosion Is to allow more work per kg of steam 1,4 1,2
2,3 2,3,4 1,3: d. 2,3,4
Question: Which of the following are integral superheaters? High pressure types Convection types Radiant
types High temperature types 1,4 1,3 2,3 3,4 2,4
Correct Answer: c. 2,3
Question: The temperature of the boiler feed water rises a. 1,2,3 b. 2,3 c. 1,3 d. 4 e. 1,4
Correct Answer: a. 1,2,3
Question: Which of the following has a rising steam temperature characteristic? a. Radiant superheater b.
Pendent superheater c. Horizontal superheater d. Convection superheater e. separately fired superheater
Correct Answer: d. Convection superheater
Question: Which of the following has a falling steam temperature characteristic? a. Radiant superheater b.
Pendent superheater c. Horizontal superheater d. Convection superheater e. separately fired superheater
Correct Answer: a. Radiant superheater
Question: Superheated steam temperatures remain fairly constant at all boiler loads a. 1,3,4 b. 1,2,3,4 c.
1,2,3 d. 2,3 e. 2,3,4
Correct Answer: b. 1,2,3,4
Question: Which of the following correctly describes the manner in which pendent superheaters are
suspended? a. Horizontal b. Inclined at an angle of 60 degrees c. Vertical d. Inclined at an angle of 45
degrees e. inclined at an angle of 30 degrees
Correct Answer: c. Vertical
Question: A convection superheater
Correct Answer: a. Has the combustion air passing across it b. Is always located in the radiant furnace
zone c. Has the hot combustion gases passing over it d. Is located after the economizer e. is indirect contact
with the flame: c. Has the hot combustion gases passing over it
Question: A primary superheater
Correct Answer: a. Has the hottest gases passing across it b. Is always located in the radiant furnace zone
c. Is the most important superheater d. Receives the saturated steam from the steam drum e. is always
located in the convection zone: d. Receives the saturated steam from the steam drum
Question: Superheated steam
Correct Answer: a. Can be produced in the saturated steam drum of a water tube boiler b. Has a
temperature that is higher than the saturation temperature for that pressure c. Is almost dry and contains
very little moisture d. Cannot be used for soot blowers e. may cause erosion of turbine blades: b. Has a
temperature that is higher than the saturation temperature for that pressure
Question: Which of the following are types of superheaters