MN BOILER EXAM QUESTIONS AND ANSWERS FULLY SOLVED #6
Cast Iron Sectional Boiler - correct answer Like Bread, sections in between are
intermediate.
Held together with push nipples and stay bolts.
No special foundation required
Expandable (can add more centers to increase heating capacity)
Boiler trim mounted on end sections
Disadvantage: Always low pressure
Advantage: corrosion resistant
Firetube boiler - correct answer used for heating and process
Gas/heat of combustion on one side and water on outside.
Horizontal Return Tubular - correct answer Type of firetube
Drum supported by Lugs and Slings
Old construction, not efficient because of *External furnace*
2 pass construction
Bridgewall - correct answer Baffle inside HRT boiler furnace to direct flow of combusting
gases for greatest efficiency
Scotch Marine - correct answer Most common, most efficient Firetube boiler.
Comes in 2, 3, or 4 pass construction
Round tube furnace usually corrugated like culvert under road.
*Completely internal furnace*
Dry Back Scotch Marine - correct answer easy to clean and maintain, less costly, less
efficient
Wet Back Scotch Marine - correct answer hard to clean and service due to limited
access, more efficient, more costly
Fire Box - correct answer almost like Scotch Marine but fire box instead of corrugated.
Can burn oil, gas, or solid materials
Locomotive - correct answer Type of firetube used in trains. Variation of HRT, partially
enclosed furnace
Vertical Fire Tube - correct answer Burner on bottom, could be on top in case of Fultons
Types of Water Tube Boilers - correct answer Straight Tube, Bent Tube, Flex tube, and
Membrane tube
Water Tube Boiler - correct answer package boilers made in factory, add water/electric
and ready to go. Process and power generation.
, Advantage of Water Tubes over Fire Tubes - correct answer WTB contains less water
for same horsepower output of FTB. Most of energy is contained in water not steam.
Recovery rate is greater than fire tube because of less water. (Less energy to heat
smaller mass)
3 Types of Industrial Water Tubes - correct answer A, O, and D (most efficient, most
common)
Electric Boiler - correct answer Electrode (spark plug) electrical arc or fusion,
Resistance coil
1 boiler Horsepower - correct answer =746 watts = 33,478.8 Btu output / hr
=10 square feet of heating surface for conventional boiler
=5 square ft of heating surface for steam coil generator
=10 KW electric
Boiler trim - correct answer Valves and components directly attached to boiler
necessary for it to run. (ex. Water column, gauge glass vent, bottom blowdown, relief
valve, steam safety valve)
Boiler Accessories - correct answer components necessary for boiler to run but NOT
attached to boiler (Feed pump, fuel pump, condensate tank and pump, surge tank,
Deaerator)
Stays - correct answer Support boiler in areas not supported by tubes. Can be vertical,
horizontal, and diagonal
Boiler Pass - correct answer where heat of combustion travels length of furnace or
boiler tubes
Baffle - correct answer used in all boilers (fireside and waterside) to direct flow for
greatest efficiency
How is piping measured vs. Boiler tubes - correct answer piping is measured based on
inside diameter, while boiler tubes are measured by outside diameter
Dry Pipe - correct answer Pipe running along the top of steam space in which slots are
cut in top or side for purpose of admitting only dry steam to line. One has blank ending,
other is connected to steam outlet. Drain holes drilled on bottom.
What is the point of a dry pipe - correct answer to aid in removal of moisture from steam
as it leaves the steam drum
What kind of stamp must a company posses to to weld on boilers - correct answer R
stamp
Cast Iron Sectional Boiler - correct answer Like Bread, sections in between are
intermediate.
Held together with push nipples and stay bolts.
No special foundation required
Expandable (can add more centers to increase heating capacity)
Boiler trim mounted on end sections
Disadvantage: Always low pressure
Advantage: corrosion resistant
Firetube boiler - correct answer used for heating and process
Gas/heat of combustion on one side and water on outside.
Horizontal Return Tubular - correct answer Type of firetube
Drum supported by Lugs and Slings
Old construction, not efficient because of *External furnace*
2 pass construction
Bridgewall - correct answer Baffle inside HRT boiler furnace to direct flow of combusting
gases for greatest efficiency
Scotch Marine - correct answer Most common, most efficient Firetube boiler.
Comes in 2, 3, or 4 pass construction
Round tube furnace usually corrugated like culvert under road.
*Completely internal furnace*
Dry Back Scotch Marine - correct answer easy to clean and maintain, less costly, less
efficient
Wet Back Scotch Marine - correct answer hard to clean and service due to limited
access, more efficient, more costly
Fire Box - correct answer almost like Scotch Marine but fire box instead of corrugated.
Can burn oil, gas, or solid materials
Locomotive - correct answer Type of firetube used in trains. Variation of HRT, partially
enclosed furnace
Vertical Fire Tube - correct answer Burner on bottom, could be on top in case of Fultons
Types of Water Tube Boilers - correct answer Straight Tube, Bent Tube, Flex tube, and
Membrane tube
Water Tube Boiler - correct answer package boilers made in factory, add water/electric
and ready to go. Process and power generation.
, Advantage of Water Tubes over Fire Tubes - correct answer WTB contains less water
for same horsepower output of FTB. Most of energy is contained in water not steam.
Recovery rate is greater than fire tube because of less water. (Less energy to heat
smaller mass)
3 Types of Industrial Water Tubes - correct answer A, O, and D (most efficient, most
common)
Electric Boiler - correct answer Electrode (spark plug) electrical arc or fusion,
Resistance coil
1 boiler Horsepower - correct answer =746 watts = 33,478.8 Btu output / hr
=10 square feet of heating surface for conventional boiler
=5 square ft of heating surface for steam coil generator
=10 KW electric
Boiler trim - correct answer Valves and components directly attached to boiler
necessary for it to run. (ex. Water column, gauge glass vent, bottom blowdown, relief
valve, steam safety valve)
Boiler Accessories - correct answer components necessary for boiler to run but NOT
attached to boiler (Feed pump, fuel pump, condensate tank and pump, surge tank,
Deaerator)
Stays - correct answer Support boiler in areas not supported by tubes. Can be vertical,
horizontal, and diagonal
Boiler Pass - correct answer where heat of combustion travels length of furnace or
boiler tubes
Baffle - correct answer used in all boilers (fireside and waterside) to direct flow for
greatest efficiency
How is piping measured vs. Boiler tubes - correct answer piping is measured based on
inside diameter, while boiler tubes are measured by outside diameter
Dry Pipe - correct answer Pipe running along the top of steam space in which slots are
cut in top or side for purpose of admitting only dry steam to line. One has blank ending,
other is connected to steam outlet. Drain holes drilled on bottom.
What is the point of a dry pipe - correct answer to aid in removal of moisture from steam
as it leaves the steam drum
What kind of stamp must a company posses to to weld on boilers - correct answer R
stamp
