DC BOILER 1ST FINAL EXAM QUESTIONS AND ANSWERS
GRADED A+
✔✔Conversion factor for grains per gallon to parts per million - ✔✔17.1
✔✔Weight of column of mercury in psi = - ✔✔= 13.57 x .433 x Height
✔✔Formula for the horsepower requirement for a pump = - ✔✔(Q x 8.33 x H x sp.gr. ) /
33,000 x n
Q = flow rate in gpm
H = total head
sp.gr. = specific gravity of fluid being pumped
n = Pump efficiency
✔✔1 lb of chemical to 1000 gallons of water = x ppm - ✔✔120 ppm
✔✔Target pH for boiler water - ✔✔10.5 - 11.0
✔✔Target pH for condensate = - ✔✔8.3
✔✔Target for Total Dissolved Solids (TDS) in steam boiler water - ✔✔2000 - 2500
micromhos
✔✔Target for Total Dissolved Solids (TDS) in a hot water boiler - ✔✔3500 micromhos
✔✔Water Horsepower = - ✔✔= (Q x H) / 3960
Q = flow rate in gpm
H = Head
✔✔Flow rate of a pump (Q) = - ✔✔= (3960 x WHP) / H
Q = flow rate
WHP = water horsepower
H = Head
✔✔Solve for total head for a pump = - ✔✔= (3960 x WHP) / Q
WHP = water horsepower
Q = flow rate
✔✔Solve for pump efficiency (n) = - ✔✔= WHP / BHP
WHP = water horsepower
BHP = brake horsepower
✔✔Pump brake horsepower (BHP) - ✔✔= 100QH) / 3960n
Q = flow rate
, H = Head
n = pump efficiency
✔✔Critical pressure and temperature of steam - ✔✔3206 psia @ 705°F
✔✔Above ____°F & ______ psi a hot water boiler is considered "high pressure" -
✔✔250°F & 160 psi
✔✔Max pressure for a fire tube boiler - ✔✔250-350 psi
✔✔Max horsepower of a fire tube boiler - ✔✔750-1000 HP
✔✔If a stay bolt is longer than 8", then it is considered a ____ - ✔✔Through stay
✔✔A 10°F rise in feed water temperature results in a ____ increase in efficiency -
✔✔1%
✔✔There are ___ gallons in a cubic foot of water - ✔✔7.5 galons
✔✔Pop type safety valves work up to ___ psi - ✔✔600 psi
✔✔During an accumulation test the pressure in the boiler cannot exceed the MAWP by
more than ___% - ✔✔6 %
✔✔The target residual value for sodium sulfite is _____ - ✔✔30-40 ppm
✔✔A dearator stores how much feedwater? - ✔✔20-30 minutes supply
✔✔A single element feedwater heater responds to ____ - ✔✔water level
✔✔A two element feedwater heater responds to ____ - ✔✔water level & steam flow
✔✔A three element feedwater heater responds to ____ - ✔✔water level, steam flow, &
feedwater flow
✔✔#2 fuel oil contains approximately ______ Btu/gal - ✔✔141,000
✔✔#6 fuel oil contains approximately _____ Btu/gal - ✔✔155,000
✔✔Fuel oil weighs approximately ___ lbs/gal - ✔✔8 lbs
✔✔Air is approximately ___% oxygen and ___ % nitrogen - ✔✔21, 79
GRADED A+
✔✔Conversion factor for grains per gallon to parts per million - ✔✔17.1
✔✔Weight of column of mercury in psi = - ✔✔= 13.57 x .433 x Height
✔✔Formula for the horsepower requirement for a pump = - ✔✔(Q x 8.33 x H x sp.gr. ) /
33,000 x n
Q = flow rate in gpm
H = total head
sp.gr. = specific gravity of fluid being pumped
n = Pump efficiency
✔✔1 lb of chemical to 1000 gallons of water = x ppm - ✔✔120 ppm
✔✔Target pH for boiler water - ✔✔10.5 - 11.0
✔✔Target pH for condensate = - ✔✔8.3
✔✔Target for Total Dissolved Solids (TDS) in steam boiler water - ✔✔2000 - 2500
micromhos
✔✔Target for Total Dissolved Solids (TDS) in a hot water boiler - ✔✔3500 micromhos
✔✔Water Horsepower = - ✔✔= (Q x H) / 3960
Q = flow rate in gpm
H = Head
✔✔Flow rate of a pump (Q) = - ✔✔= (3960 x WHP) / H
Q = flow rate
WHP = water horsepower
H = Head
✔✔Solve for total head for a pump = - ✔✔= (3960 x WHP) / Q
WHP = water horsepower
Q = flow rate
✔✔Solve for pump efficiency (n) = - ✔✔= WHP / BHP
WHP = water horsepower
BHP = brake horsepower
✔✔Pump brake horsepower (BHP) - ✔✔= 100QH) / 3960n
Q = flow rate
, H = Head
n = pump efficiency
✔✔Critical pressure and temperature of steam - ✔✔3206 psia @ 705°F
✔✔Above ____°F & ______ psi a hot water boiler is considered "high pressure" -
✔✔250°F & 160 psi
✔✔Max pressure for a fire tube boiler - ✔✔250-350 psi
✔✔Max horsepower of a fire tube boiler - ✔✔750-1000 HP
✔✔If a stay bolt is longer than 8", then it is considered a ____ - ✔✔Through stay
✔✔A 10°F rise in feed water temperature results in a ____ increase in efficiency -
✔✔1%
✔✔There are ___ gallons in a cubic foot of water - ✔✔7.5 galons
✔✔Pop type safety valves work up to ___ psi - ✔✔600 psi
✔✔During an accumulation test the pressure in the boiler cannot exceed the MAWP by
more than ___% - ✔✔6 %
✔✔The target residual value for sodium sulfite is _____ - ✔✔30-40 ppm
✔✔A dearator stores how much feedwater? - ✔✔20-30 minutes supply
✔✔A single element feedwater heater responds to ____ - ✔✔water level
✔✔A two element feedwater heater responds to ____ - ✔✔water level & steam flow
✔✔A three element feedwater heater responds to ____ - ✔✔water level, steam flow, &
feedwater flow
✔✔#2 fuel oil contains approximately ______ Btu/gal - ✔✔141,000
✔✔#6 fuel oil contains approximately _____ Btu/gal - ✔✔155,000
✔✔Fuel oil weighs approximately ___ lbs/gal - ✔✔8 lbs
✔✔Air is approximately ___% oxygen and ___ % nitrogen - ✔✔21, 79
