250+ TOP MCQs on Fire Tube Boilers – I and Answers

Power Plant Engineering Multiple Choice Questions on “Fire Tube Boilers – I”.

1. Fire-tube boilers are used in?
a) industrial steam generators
b) utility steam generators
c) marine steam generators
d) none of the mentioned
Answer: a
Clarification: Industrial steam generators use fire-tube boilers as they suit the most for the quantity of steam in the industrial steam generators.

2. Which of the following is not an advantage of a fire-tube boiler?
a) low first cost
b) reliability in operation
c) more draught required
d) quick response to load changes
Answer: c
Clarification: The advantages of using a fire tube boiler are low first cost, reliability in operation, less draught required, quick response to load changes, etc.

3. Which of these is a type of fire-tube boiler?
a) Externally fired
b) Internally fired
c) Internally & Externally fired
d) None of the mentioned
Answer: c
Clarification: There are two types of a fire-tube boiler which are Internally & Externally fired boilers.

4. Which of these is an externally fired boiler?
a) Package boiler
b) Scotch-marine boiler
c) Lancashire boiler
d) None of the mentioned
Answer: c
Clarification: The various types of externally fired boiler include Lancashire boilers, Locomotive type boilers, HRT boiler, etc.

5. Which of the following is a type of internally fired boiler?
a) Package boiler
b) HRT boiler
c) Lancashire boiler
d) Locomotive type boiler
Answer: a
Clarification: The various types of an internally fired boiler include Scotch-marine boiler, Package boiler, etc.

6. What is the function of the fusible plug installed in a furnace?
a) to detect excess current
b) to detect excess heat
c) to detect water level in the tube
d) to detect water level in the shell
Answer: d
Clarification: Water level in the shell is detected by the fusible plug installed in the crown of the furnace.

7. Which of the following gaseous fuels has the lowest calorific value?
a) Refinery Gas
b) Gobar Gas
c) Converter Gas
d) Blast Furnace Gas
Answer: d
Clarification: The lowest calorific value fuel means a fuel which burns most readily. Among all the given options, the most combustible gas is the blast furnace gas.

8. Fuel gases containing hydrocarbons (e.g. coke oven gas) are not preheated before burning, mainly because ____________
a) there are chances of explosion during preheating
b) it reduces its calorific value tremendously
c) the hydrocarbons crack thereby choking and fouling the heat transfer surface by carbon soot
d) it reduces its flame temperature tremendously
Answer: c
Clarification: Fuel gases containing hydrocarbons (i.e. coke oven gas) are not preheated before burning, mainly because the hydrocarbons crack thereby choking and fouling the heat transfer surface by carbon soot.

9. Flue gas discharge velocity through chimney of a big thermal power plant may be around __________ m/sec.
a) 500
b) 0.5
c) 10
d) 50
Answer: c
Clarification: The velocity of discharge of flue gases through the chimney of a big thermal power plant is around 10 m/sec.

10. In water tube boilers ___________
a) forced circulation takes place
b) water passes through the tubes which are surrounded by flames and hot gases
c) the flames and hot gases pass through the tubes which are surrounded by water
d) none of the mentioned
Answer: c
Clarification: In water tube boilers the flames and hot gases pass through the tubes which are surrounded by water.