DC BOILER EXAM 2024-2025 ACTUAL EXAM COMPLETE 240 QUESTIONS AND CORRECT DETAILED
ANSWERS
Area of a rectangle - (answer) Length x Width
Area of a Circle - (answer) .7854 x Diameter²
Volume of a Box - (answer) Length x Width x Height
Volume of a Cylinder - (answer) .7854 x Diameter² x Length
Circumference of a Circle - (answer) π x Diameter
Unit of Force - (answer) Pound (lb)
Formula for Force - (answer) Pressure ÷ Area
Unit of Work - (answer) in-lb or ft-lb
Formula for Work - (answer) Force x Distance
Unit of Power - (answer) ft-lb/min
Formula for Power - (answer) = Work ÷ Time
or (Force x Distance) ÷ Time
Formula for Mechanical Horsepower - (answer) = Power ÷ 33,000 ft-lb/min
Fahrenheit to Celsius - (answer) °C = (°F - 32) ÷ 1.8
Celsius to Fahrenheit - (answer) °F = (1.8 x °C) - 32
,DC BOILER EXAM 2024-2025 ACTUAL EXAM COMPLETE 240 QUESTIONS AND CORRECT DETAILED
ANSWERS
Fahrenheit to Rankine - (answer) °R = °F + 460
Celsius to Kelvin - (answer) K = °C +273.15
Charles' First Law - (answer) Volume1 / Pressure1 = Volume2 / Pressure2
Charles' Second Law - (answer) Pressure1 / Temperature1 = Pressure2 / Temperature2
Boyle's Law - (answer) Pressure1 x Volume1 = Pressure2 x Volume2
General Gas Law - (answer) (Pres1 x Vol1)/ Temp1 = (Pres2 x Vol2)/Temp2
Formula for Levers - (answer) Resistance x DistanceR = Effort x DistanceE
Formula for Inclined Planes - (answer) Force x Length = Resistance x Height
Formula for Wheel & Axel - (answer) Force x DistanceF = Resistance x DistanceR
Torque - (answer) Force x Radius
Safe Working Pressure of a Riveted Boiler (SWP) - (answer) (Area of Staybolt x Stress Constant of
Staybolt) ÷ Area Covered by Staybolt or = (a x C) ÷ A
Area Covered by Staybolt - (answer) = Pitch x Pitch
Longitudinal Stress - (answer) (P x D x L) / 2t
P = Pressure
, DC BOILER EXAM 2024-2025 ACTUAL EXAM COMPLETE 240 QUESTIONS AND CORRECT DETAILED
ANSWERS
D = Diameter
L = Length
t = thickness of steel
Boiler Heating Surface (tubes) = - (answer) = C x L x #
C = Circumference of tubes
L = Length of tubes
# = Number of tubes
HS = π x Diameter x Length x Number of Tubes
Watts per Boiler Horsepower - (answer) 746 Watts
Horsepower formula - (answer) = ft-lb/min ÷ 33000 ft-lb/min
ft-lb formula for a pump - (answer) = gpm x 8.33 x head (ft)
Factor of Evaporation (FE) = - (answer) = [Hs - (tfw-32)] ÷ 970.3
Hs = Enthalpy of steam
tfw = temperature of feed water
Latent Heat of Vaporization for Water - (answer) 970.3 Btu/lb
Latent Heat of Fusion for Water - (answer) 144 Btu/lb
1 Boiler Horsepower = x lbs of steam generator per hour - (answer) 34.5 lbs/hr
1 Boiler Horsepower = x Btu/hr - (answer) 33,475 Btu/hr
ANSWERS
Area of a rectangle - (answer) Length x Width
Area of a Circle - (answer) .7854 x Diameter²
Volume of a Box - (answer) Length x Width x Height
Volume of a Cylinder - (answer) .7854 x Diameter² x Length
Circumference of a Circle - (answer) π x Diameter
Unit of Force - (answer) Pound (lb)
Formula for Force - (answer) Pressure ÷ Area
Unit of Work - (answer) in-lb or ft-lb
Formula for Work - (answer) Force x Distance
Unit of Power - (answer) ft-lb/min
Formula for Power - (answer) = Work ÷ Time
or (Force x Distance) ÷ Time
Formula for Mechanical Horsepower - (answer) = Power ÷ 33,000 ft-lb/min
Fahrenheit to Celsius - (answer) °C = (°F - 32) ÷ 1.8
Celsius to Fahrenheit - (answer) °F = (1.8 x °C) - 32
,DC BOILER EXAM 2024-2025 ACTUAL EXAM COMPLETE 240 QUESTIONS AND CORRECT DETAILED
ANSWERS
Fahrenheit to Rankine - (answer) °R = °F + 460
Celsius to Kelvin - (answer) K = °C +273.15
Charles' First Law - (answer) Volume1 / Pressure1 = Volume2 / Pressure2
Charles' Second Law - (answer) Pressure1 / Temperature1 = Pressure2 / Temperature2
Boyle's Law - (answer) Pressure1 x Volume1 = Pressure2 x Volume2
General Gas Law - (answer) (Pres1 x Vol1)/ Temp1 = (Pres2 x Vol2)/Temp2
Formula for Levers - (answer) Resistance x DistanceR = Effort x DistanceE
Formula for Inclined Planes - (answer) Force x Length = Resistance x Height
Formula for Wheel & Axel - (answer) Force x DistanceF = Resistance x DistanceR
Torque - (answer) Force x Radius
Safe Working Pressure of a Riveted Boiler (SWP) - (answer) (Area of Staybolt x Stress Constant of
Staybolt) ÷ Area Covered by Staybolt or = (a x C) ÷ A
Area Covered by Staybolt - (answer) = Pitch x Pitch
Longitudinal Stress - (answer) (P x D x L) / 2t
P = Pressure
, DC BOILER EXAM 2024-2025 ACTUAL EXAM COMPLETE 240 QUESTIONS AND CORRECT DETAILED
ANSWERS
D = Diameter
L = Length
t = thickness of steel
Boiler Heating Surface (tubes) = - (answer) = C x L x #
C = Circumference of tubes
L = Length of tubes
# = Number of tubes
HS = π x Diameter x Length x Number of Tubes
Watts per Boiler Horsepower - (answer) 746 Watts
Horsepower formula - (answer) = ft-lb/min ÷ 33000 ft-lb/min
ft-lb formula for a pump - (answer) = gpm x 8.33 x head (ft)
Factor of Evaporation (FE) = - (answer) = [Hs - (tfw-32)] ÷ 970.3
Hs = Enthalpy of steam
tfw = temperature of feed water
Latent Heat of Vaporization for Water - (answer) 970.3 Btu/lb
Latent Heat of Fusion for Water - (answer) 144 Btu/lb
1 Boiler Horsepower = x lbs of steam generator per hour - (answer) 34.5 lbs/hr
1 Boiler Horsepower = x Btu/hr - (answer) 33,475 Btu/hr
