City of Omaha 3rd Grade N.A.P.E. Stationary Engineers Test
2023 (Correctly answered questions)
1. How can you lose your license?: Drinking on the job / sleeping on the job / negligence / unsafe
work / failing to renew your license annually / signing a falsified licensing application for someone
2. What must you do if you change jobs?: You must notify city hall if you change jobs, change your
address or if you retire
3. Why should you do rounds?: You do rounds so that you can find and correct problems to
prevent break downs. Keeping permanent records will make it easier to forecast most breakdowns
because you will get to know your equipment.
4. What is a steam Boiler?: A steam boiler is a closed vessel PARTIALLY FILLED with water, under
pressure, that transforms water into steam with the application of heat.
5. What are requirements of a good boiler?: 1. simple
2. designed to accommodate expansion and contraction
3. adequate steam and water space
4. efficient
5. responsive to demands
6. accessible for cleaning and repair
7. safe
6. Name and describe three types of heat transfer used in boiler operation.-
: RADIANT HEAT-is heat radiated from a hot to cold body and depends on the temperature
difference and the color of the body that receives the heat. The heat from the sun reaches us by
means of radiation.
CONDUCTION HEAT-is heat that passes from the gas to the tube by physical contact. The heat
passes from molecule of metal to molecule of metal with no displacement of the molecules.
CONVECTION HEAT-is heat transmitted from a hot to cold body by movement of the conveying
substance.
7. What is a combustion chamber?: The area of a boiler where the burning of fuel occurs
8. What is an internally fired boiler and name 4 types.: Internally fired boilers are those in which
the grate and combustion chamber are enclosed within the boiler shell.
Scotch Marine Cast
iron package
1/
, City of Omaha 3rd Grade N.A.P.E. Stationary Engineers Test
2023 (Correctly answered questions)
Steam locomotive
Vertical fire tube
9. What is an externally fired boiler and name 4 types.: Externally fired boiler is a boiler in which
the setting, including furnace and grates are separate and distinct from the boiler shell.
Horizontal return tube set on brick Heine
Cast iron set on brick
Sterling water tube
10.What is a crown sheet and what is its purpose? What is a tube sheet and what is its purpose?:
The crown sheet in a vertical fire tube boiler holds the tubes and is thicker because it is exposed to
fire.
The tube sheet holds the tubes and does not see the fire.
11.What is a water leg on a boiler?: A water leg is the space between the outer shell and the
furnace shell containing boiler water. It absorbs heat that would be wasted and increases the
capacity of the boiler. The surfaces are flat and must be stayed.
12.Is an H.R.T. boiler set level or inclined and why?: H.R.T. boilers are inclined 1-3 inches front to
rear, for drainage and removal of impurities.
Boiler tubes are just inclined with the boiler shell.
13.Name 2 ways to support and take care of expansion of an H.R.T. boiler. Which way is the
best?: H.R.T. boiler can be set on saddles on the furnace wall, 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 from beams works no hardship on furnace walls.
14.What is a longitudinal joint? What is a circumferential joint?: A longitudinal joint is a seam
running the length of the shell and is butt strap construction or fusion welded. It is above the fire line
to avoid overheating.
A circumferential joint is a lap joint running the circumference of the joint.
15.What is the difference between a flue and a tube?: A tube is 4 inches or less in diameter
measured externally.
2/
2023 (Correctly answered questions)
1. How can you lose your license?: Drinking on the job / sleeping on the job / negligence / unsafe
work / failing to renew your license annually / signing a falsified licensing application for someone
2. What must you do if you change jobs?: You must notify city hall if you change jobs, change your
address or if you retire
3. Why should you do rounds?: You do rounds so that you can find and correct problems to
prevent break downs. Keeping permanent records will make it easier to forecast most breakdowns
because you will get to know your equipment.
4. What is a steam Boiler?: A steam boiler is a closed vessel PARTIALLY FILLED with water, under
pressure, that transforms water into steam with the application of heat.
5. What are requirements of a good boiler?: 1. simple
2. designed to accommodate expansion and contraction
3. adequate steam and water space
4. efficient
5. responsive to demands
6. accessible for cleaning and repair
7. safe
6. Name and describe three types of heat transfer used in boiler operation.-
: RADIANT HEAT-is heat radiated from a hot to cold body and depends on the temperature
difference and the color of the body that receives the heat. The heat from the sun reaches us by
means of radiation.
CONDUCTION HEAT-is heat that passes from the gas to the tube by physical contact. The heat
passes from molecule of metal to molecule of metal with no displacement of the molecules.
CONVECTION HEAT-is heat transmitted from a hot to cold body by movement of the conveying
substance.
7. What is a combustion chamber?: The area of a boiler where the burning of fuel occurs
8. What is an internally fired boiler and name 4 types.: Internally fired boilers are those in which
the grate and combustion chamber are enclosed within the boiler shell.
Scotch Marine Cast
iron package
1/
, City of Omaha 3rd Grade N.A.P.E. Stationary Engineers Test
2023 (Correctly answered questions)
Steam locomotive
Vertical fire tube
9. What is an externally fired boiler and name 4 types.: Externally fired boiler is a boiler in which
the setting, including furnace and grates are separate and distinct from the boiler shell.
Horizontal return tube set on brick Heine
Cast iron set on brick
Sterling water tube
10.What is a crown sheet and what is its purpose? What is a tube sheet and what is its purpose?:
The crown sheet in a vertical fire tube boiler holds the tubes and is thicker because it is exposed to
fire.
The tube sheet holds the tubes and does not see the fire.
11.What is a water leg on a boiler?: A water leg is the space between the outer shell and the
furnace shell containing boiler water. It absorbs heat that would be wasted and increases the
capacity of the boiler. The surfaces are flat and must be stayed.
12.Is an H.R.T. boiler set level or inclined and why?: H.R.T. boilers are inclined 1-3 inches front to
rear, for drainage and removal of impurities.
Boiler tubes are just inclined with the boiler shell.
13.Name 2 ways to support and take care of expansion of an H.R.T. boiler. Which way is the
best?: H.R.T. boiler can be set on saddles on the furnace wall, 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 from beams works no hardship on furnace walls.
14.What is a longitudinal joint? What is a circumferential joint?: A longitudinal joint is a seam
running the length of the shell and is butt strap construction or fusion welded. It is above the fire line
to avoid overheating.
A circumferential joint is a lap joint running the circumference of the joint.
15.What is the difference between a flue and a tube?: A tube is 4 inches or less in diameter
measured externally.
2/
