3rd Stationary Engineer Test Questions and Correct Answers
Question 1
AB 6. 3 types of heat transfer
Correct Answer
Radiant heat - Transmitted from hot body to a cold body by means of direct radiation
Co
Question 2
A 7. What is a combustion chamber?
Correct Answer
The area of the boiler where the complete burning of fuel occurs.
Question 3
B 8. What is an internally fired boiler and 4 types
Correct Answer
Internally fired boilers have the grates and combustion chamber enclosed within the boiler shell.
Scotch Marine
Vertical Fire Tube
Locomotive
Cast Iron Package
Page 1 of 50
,Question 4
B 13. Name 2 ways to support and take care of expansion in a HRT boiler. Which way is best?
Correct Answer
It can be set on saddles equipped with rollers to permit movement of the boiler as it expands and contracts. It may also
be suspended from hangers and supported by overhead beams.
Hanging by beams is best, puts no hardship on furnace walls.
Question 5
B 14. What is a longitudinal Joint?
What is a circumfermential joint?
Correct Answer
A longitudinal joint is a seam running the length of the shell and it is butt strapped or fusion welded. It is above the fire
line to avoid overheating.
Lap joint running the circumference of the drum.
Question 6
B 17.Describe a scotch marine boiler and how its fired
Correct Answer
It is an internally fired self contained horizontal return fire boiler. It is a cylindrical shell containing the combustion
chamber and tubes that are surrounded by water.
Page 2 of 50
,Question 7
B 19. Describe the circulation of water within a Stirling boiler.
Correct Answer
feed water enters the top rear drum, passes down the rear tubes to the mud drum. steam and boiler water go up the
front and center tubes to the front and center drums. CIRCULATING TUBES allow boiler water to pass between the drums.
what does not go out as steam, goes back down the rear tubes.
Question 8
B 23. What type of stays are used in a wet back scotch marine boiler.
Correct Answer
Stay bolts and through stays. These sometimes will have a telltale drilled in them.
Question 9
B 25. What is a super heater? What are the advantages?
Correct Answer
A bank of tubes through which only steam passes through without raising pressure.
Advantages: increased efficiency of boilers, delivering drier steam. Drier steam can be transmitted long distances with
minimal heat loss. With drier steam condensation and corrosion are reduced.
Page 3 of 50
, Question 10
B 27. What is an economize? What is an air preheater?
Correct Answer
Economizer: heat exchanger located in the breaching between the boiler and stack designed to recover waste heat from
the products of combustion by preheating the feedwater
Air preheater: consists of a series of tubes or plates that have hot gases on one side and incoming air on the other. heat
in the hot gasses leaving the boiler is recovered by the incoming air.
both reduce stack temperatures and increase boiler efficiency
Question 11
B 30. Cross section of a 1" bolt
Correct Answer
D x D x .7854
1 x 1 x .7854 = .7854sq"
Question 12
B 33. What is meant by "factor of safety"
Correct Answer
The comparison of the tensile strength to the actual working stress or the bursting pressure divided by the working
pressure.
Page 4 of 50
Question 1
AB 6. 3 types of heat transfer
Correct Answer
Radiant heat - Transmitted from hot body to a cold body by means of direct radiation
Co
Question 2
A 7. What is a combustion chamber?
Correct Answer
The area of the boiler where the complete burning of fuel occurs.
Question 3
B 8. What is an internally fired boiler and 4 types
Correct Answer
Internally fired boilers have the grates and combustion chamber enclosed within the boiler shell.
Scotch Marine
Vertical Fire Tube
Locomotive
Cast Iron Package
Page 1 of 50
,Question 4
B 13. Name 2 ways to support and take care of expansion in a HRT boiler. Which way is best?
Correct Answer
It can be set on saddles equipped with rollers to permit movement of the boiler as it expands and contracts. It may also
be suspended from hangers and supported by overhead beams.
Hanging by beams is best, puts no hardship on furnace walls.
Question 5
B 14. What is a longitudinal Joint?
What is a circumfermential joint?
Correct Answer
A longitudinal joint is a seam running the length of the shell and it is butt strapped or fusion welded. It is above the fire
line to avoid overheating.
Lap joint running the circumference of the drum.
Question 6
B 17.Describe a scotch marine boiler and how its fired
Correct Answer
It is an internally fired self contained horizontal return fire boiler. It is a cylindrical shell containing the combustion
chamber and tubes that are surrounded by water.
Page 2 of 50
,Question 7
B 19. Describe the circulation of water within a Stirling boiler.
Correct Answer
feed water enters the top rear drum, passes down the rear tubes to the mud drum. steam and boiler water go up the
front and center tubes to the front and center drums. CIRCULATING TUBES allow boiler water to pass between the drums.
what does not go out as steam, goes back down the rear tubes.
Question 8
B 23. What type of stays are used in a wet back scotch marine boiler.
Correct Answer
Stay bolts and through stays. These sometimes will have a telltale drilled in them.
Question 9
B 25. What is a super heater? What are the advantages?
Correct Answer
A bank of tubes through which only steam passes through without raising pressure.
Advantages: increased efficiency of boilers, delivering drier steam. Drier steam can be transmitted long distances with
minimal heat loss. With drier steam condensation and corrosion are reduced.
Page 3 of 50
, Question 10
B 27. What is an economize? What is an air preheater?
Correct Answer
Economizer: heat exchanger located in the breaching between the boiler and stack designed to recover waste heat from
the products of combustion by preheating the feedwater
Air preheater: consists of a series of tubes or plates that have hot gases on one side and incoming air on the other. heat
in the hot gasses leaving the boiler is recovered by the incoming air.
both reduce stack temperatures and increase boiler efficiency
Question 11
B 30. Cross section of a 1" bolt
Correct Answer
D x D x .7854
1 x 1 x .7854 = .7854sq"
Question 12
B 33. What is meant by "factor of safety"
Correct Answer
The comparison of the tensile strength to the actual working stress or the bursting pressure divided by the working
pressure.
Page 4 of 50
