MD Stationary Engineer Exam Questions
with All Correct Answers
How much clearance from the top of the boiler is needed for a HP boiler that produces
70000 lbs of steam? ...ANSWER...7 feet
On a gas fired boiler what is the proper gas to air mixture ...ANSWER...30%-70% and in
special arrangements it can be as high as 100% . ANSWER CHAPTER 11 remember%
What is the total hardness in a system that was found to have calcium hardness of
60ppm and magnesium hardness of 18ppm and carbon hardness of 12
ppm? ...ANSWER...TH=(Ca x 2.5) + (Mg x 4.1)\nTH=(60 x 2.5) + (18 x 4.1)\nTH=
150+73.8 =( 223.8 PPM)
How often should a complete external inspection of the boiler be
done? ...ANSWER...Once a Shift
With 24 hr operation how often do you check the water level? ...ANSWER...Once per
shift
How often do you check the LWCO? ...ANSWER...Once per shift
How often do you check the High Limit Switch? ...ANSWER...Annually
A 2" pipe was found to be delivering water at 100 psia at 1040ft per second. How many
gallons per hour will it deliver? ...ANSWER...GPM= V (diameter squared) divided
by .4085 ANSWER pg 469 BOG
What controls the amount of blowback on a safety valve? ...ANSWER...Blowback ring
or adjusting ring
On a open air expansion tank hot water boiler system; how high should it be
mounted? ...ANSWER...(4 Feet ) above the highest heating element.
What is the minimum top clearance of boilers with manholes? ...ANSWER...5 feet
Package boilers; steam heating boilers and hot water heating boilers shall have a
minimum clearance of? ...ANSWER...2 feet from ceiling. Code chapter 10 page76
,Most important safety device on a boiler? ...ANSWER...Safety relief valve
What does a Black Liquor Boiler do? ...ANSWER...Black Liquor is the by product of
wood pulp processing in the paper making industry.
What does Black liquor boiler known for? ...ANSWER...Steam generation and recovery
of soda ash
Maximum line voltage for control on a boiler? ...ANSWER...150 volts
Under what code are boilers designed and constructed? ...ANSWER...ASME- CSD 1
How many low water cut offs are needed per code for a hot water system when a boiler
has inputs greater than 400,000 btu per hr ...ANSWER...1 LWCO is needed.
What is the minimum and maximum size for a safety valve per code for
boilers? ...ANSWER...Minimum 3/4" and Maximum 4 1/2"
What stamp is put on a boiler after repairs? ...ANSWER..."R"
What is the equalizing system used for? ...ANSWER...The equalizing system is for
warming up the steam lead.
A blowdown valve is located at the lowest water space of a boiler for three
purposes ...ANSWER...1. to remove precipitated sludge or loose scale \n2. To permit
rapid lowering of the boiler water if it has become too high accidentally \n3. As a means
of removing water from the boiler so that fresh water may be added to keep the
concentration of solids below the point where difficulties may be experienced.
In the old power boiler which type of feed-water regulators were not
used? ...ANSWER...Electronic
After opening a boiler for repairs how much oxygen is needed? ...ANSWER...19%
What is the first thing you do when shutting down a boiler? ...ANSWER...Turn off
(extinguish fire)
What is the legal limit of acceptable asbestos particles ? ...ANSWER...0.1 fibers per
cubic centimeter
What is CREEP? ...ANSWER...Creep is defined as the slow deformation of material
with time; with the deformation taking place at elevated temperatures with no increase
in stress.
What is the BTU content of Anthracite coal? ...ANSWER...14000 btu/lb
,What substance transfers electrical current in a photocell? ...ANSWER...Electricity will
flow when the CADMIUM is exposed to sufficient light.
What device acts as a check valve in both directions and keeps pumps
primed? ...ANSWER...FOOT VALVES are used for pumps under suction pressure to
prevent backflow primed? on the suction line.
What protects boilers from explosion in the furnace? ...ANSWER...A flame guard
system is an arrangement of flame detection system; interlocks; and relays which will
sense the presence of a proper flame in a furnace and cause fuel to be shut off to the
furnace if a hazardous condition develops (improper flame or combustion).
What size pipe is used as a header in a boiler operating at 100psi? ...ANSWER...6
inches
What device is used to measure flue gasses ...ANSWER...The Orsat Analyzer
Which low water cut off does not have a mercury switch? ...ANSWER...The Submerged
electrode type
What is the btu output per lb of #4 fuel oil? ...ANSWER...18
What substance is used for the electric transmission in an RTD? ...ANSWER...Platinum
is used because of its stability at high temperatures
How much air is needed for the combustion of pulverized coal; gas;
oil? ...ANSWER...50% for coal and 10-30% for gas & oil
In old power boilers which type of feedwater regulators were not used? \n(A) hydraulic \
n(B) float \n(C) thermostatic expansion \n(D) electronic ...ANSWER...ANSWER D
electronic/electro-magnetic
What is hard forming scale? ...ANSWER...Silica
With hydroxide present and normal oxygen levels which chemical will cause
problems? ...ANSWER...Chlorine
The result from steel manufacturing and under pressure in boilers tends to cause
buldging? A buldge is caused by ? ...ANSWER...A buldge is caused by overheating of
the shell plates and it affects the entire thickness of the plate.
A blister is caused by what ? ...ANSWER...Slag inclusion forming a lamination at the
time the plate was rolled at the steel mill. A blister is a separation of the metal from the
shell plate caused by impurities rolled into the shell plate when formed.
, With normal oxygen and low alkalinity. what is added to the boiler
water? ...ANSWER...Neutralizing Amines
Which chemical is used to combat scale? ...ANSWER...Combined phosphate treatment-
sodium phosphate
Other than sulfite what chemical is used to combat corrosion in
boilers? ...ANSWER...Hydrazine
What will neutralize acid? ...ANSWER...Alkali and Lime Soda
What mechanical device is used to remove scale from firetubes? ...ANSWER...A tube
rattler or vibrator
What percentage of the pressure should a boiler have before you test the lever of a
safety valve? ...ANSWER...75%
Where is internal corrosion most likely to occur on a vertical tube
boiler? ...ANSWER...Water leg-Mud leg
What are the minimum and maximum sizes permitted for blow down valves or
connections? ...ANSWER...3/4"minimum 2 ½ " maximum
A boiler operating at a pressure of 65lbs. What is the smallest size feed and blow off
connections if the safety valve is set at 90 psi? ...ANSWER...½ " feed ¾ " blow off
How often should water columns and water glass levels be checked on a high pressure
boiler? ...ANSWER...(Once A Shift)\nAt the beginning of each shift - beginning of the
work effort
What takes no actual action chemical part in combustion? ...ANSWER...Nitrogen
How many ppm of EDTA are needed to tie up 1ppm of hardness? ...ANSWER...EDTA
requires 10ppm of EDTA and 5 NTA to tie up each 1ppm hardness.
On a package boiler; how many ways could cause fire puffs when it is started
up? ...ANSWER...6 ways 1-poor starting draft 2-incorrect firebox 3-wrong burner nozzle
4-lean fire 5- insufficient gas pilot or excessive gas pilot 6-water in the oil
What is the grade of light domestic fuel oil ? ...ANSWER...Grade 1 ( Number 1 )
How often should you test the operating control? ...ANSWER...Annually
How often should the testing and inspecting of the burner
component? ...ANSWER...Annually
with All Correct Answers
How much clearance from the top of the boiler is needed for a HP boiler that produces
70000 lbs of steam? ...ANSWER...7 feet
On a gas fired boiler what is the proper gas to air mixture ...ANSWER...30%-70% and in
special arrangements it can be as high as 100% . ANSWER CHAPTER 11 remember%
What is the total hardness in a system that was found to have calcium hardness of
60ppm and magnesium hardness of 18ppm and carbon hardness of 12
ppm? ...ANSWER...TH=(Ca x 2.5) + (Mg x 4.1)\nTH=(60 x 2.5) + (18 x 4.1)\nTH=
150+73.8 =( 223.8 PPM)
How often should a complete external inspection of the boiler be
done? ...ANSWER...Once a Shift
With 24 hr operation how often do you check the water level? ...ANSWER...Once per
shift
How often do you check the LWCO? ...ANSWER...Once per shift
How often do you check the High Limit Switch? ...ANSWER...Annually
A 2" pipe was found to be delivering water at 100 psia at 1040ft per second. How many
gallons per hour will it deliver? ...ANSWER...GPM= V (diameter squared) divided
by .4085 ANSWER pg 469 BOG
What controls the amount of blowback on a safety valve? ...ANSWER...Blowback ring
or adjusting ring
On a open air expansion tank hot water boiler system; how high should it be
mounted? ...ANSWER...(4 Feet ) above the highest heating element.
What is the minimum top clearance of boilers with manholes? ...ANSWER...5 feet
Package boilers; steam heating boilers and hot water heating boilers shall have a
minimum clearance of? ...ANSWER...2 feet from ceiling. Code chapter 10 page76
,Most important safety device on a boiler? ...ANSWER...Safety relief valve
What does a Black Liquor Boiler do? ...ANSWER...Black Liquor is the by product of
wood pulp processing in the paper making industry.
What does Black liquor boiler known for? ...ANSWER...Steam generation and recovery
of soda ash
Maximum line voltage for control on a boiler? ...ANSWER...150 volts
Under what code are boilers designed and constructed? ...ANSWER...ASME- CSD 1
How many low water cut offs are needed per code for a hot water system when a boiler
has inputs greater than 400,000 btu per hr ...ANSWER...1 LWCO is needed.
What is the minimum and maximum size for a safety valve per code for
boilers? ...ANSWER...Minimum 3/4" and Maximum 4 1/2"
What stamp is put on a boiler after repairs? ...ANSWER..."R"
What is the equalizing system used for? ...ANSWER...The equalizing system is for
warming up the steam lead.
A blowdown valve is located at the lowest water space of a boiler for three
purposes ...ANSWER...1. to remove precipitated sludge or loose scale \n2. To permit
rapid lowering of the boiler water if it has become too high accidentally \n3. As a means
of removing water from the boiler so that fresh water may be added to keep the
concentration of solids below the point where difficulties may be experienced.
In the old power boiler which type of feed-water regulators were not
used? ...ANSWER...Electronic
After opening a boiler for repairs how much oxygen is needed? ...ANSWER...19%
What is the first thing you do when shutting down a boiler? ...ANSWER...Turn off
(extinguish fire)
What is the legal limit of acceptable asbestos particles ? ...ANSWER...0.1 fibers per
cubic centimeter
What is CREEP? ...ANSWER...Creep is defined as the slow deformation of material
with time; with the deformation taking place at elevated temperatures with no increase
in stress.
What is the BTU content of Anthracite coal? ...ANSWER...14000 btu/lb
,What substance transfers electrical current in a photocell? ...ANSWER...Electricity will
flow when the CADMIUM is exposed to sufficient light.
What device acts as a check valve in both directions and keeps pumps
primed? ...ANSWER...FOOT VALVES are used for pumps under suction pressure to
prevent backflow primed? on the suction line.
What protects boilers from explosion in the furnace? ...ANSWER...A flame guard
system is an arrangement of flame detection system; interlocks; and relays which will
sense the presence of a proper flame in a furnace and cause fuel to be shut off to the
furnace if a hazardous condition develops (improper flame or combustion).
What size pipe is used as a header in a boiler operating at 100psi? ...ANSWER...6
inches
What device is used to measure flue gasses ...ANSWER...The Orsat Analyzer
Which low water cut off does not have a mercury switch? ...ANSWER...The Submerged
electrode type
What is the btu output per lb of #4 fuel oil? ...ANSWER...18
What substance is used for the electric transmission in an RTD? ...ANSWER...Platinum
is used because of its stability at high temperatures
How much air is needed for the combustion of pulverized coal; gas;
oil? ...ANSWER...50% for coal and 10-30% for gas & oil
In old power boilers which type of feedwater regulators were not used? \n(A) hydraulic \
n(B) float \n(C) thermostatic expansion \n(D) electronic ...ANSWER...ANSWER D
electronic/electro-magnetic
What is hard forming scale? ...ANSWER...Silica
With hydroxide present and normal oxygen levels which chemical will cause
problems? ...ANSWER...Chlorine
The result from steel manufacturing and under pressure in boilers tends to cause
buldging? A buldge is caused by ? ...ANSWER...A buldge is caused by overheating of
the shell plates and it affects the entire thickness of the plate.
A blister is caused by what ? ...ANSWER...Slag inclusion forming a lamination at the
time the plate was rolled at the steel mill. A blister is a separation of the metal from the
shell plate caused by impurities rolled into the shell plate when formed.
, With normal oxygen and low alkalinity. what is added to the boiler
water? ...ANSWER...Neutralizing Amines
Which chemical is used to combat scale? ...ANSWER...Combined phosphate treatment-
sodium phosphate
Other than sulfite what chemical is used to combat corrosion in
boilers? ...ANSWER...Hydrazine
What will neutralize acid? ...ANSWER...Alkali and Lime Soda
What mechanical device is used to remove scale from firetubes? ...ANSWER...A tube
rattler or vibrator
What percentage of the pressure should a boiler have before you test the lever of a
safety valve? ...ANSWER...75%
Where is internal corrosion most likely to occur on a vertical tube
boiler? ...ANSWER...Water leg-Mud leg
What are the minimum and maximum sizes permitted for blow down valves or
connections? ...ANSWER...3/4"minimum 2 ½ " maximum
A boiler operating at a pressure of 65lbs. What is the smallest size feed and blow off
connections if the safety valve is set at 90 psi? ...ANSWER...½ " feed ¾ " blow off
How often should water columns and water glass levels be checked on a high pressure
boiler? ...ANSWER...(Once A Shift)\nAt the beginning of each shift - beginning of the
work effort
What takes no actual action chemical part in combustion? ...ANSWER...Nitrogen
How many ppm of EDTA are needed to tie up 1ppm of hardness? ...ANSWER...EDTA
requires 10ppm of EDTA and 5 NTA to tie up each 1ppm hardness.
On a package boiler; how many ways could cause fire puffs when it is started
up? ...ANSWER...6 ways 1-poor starting draft 2-incorrect firebox 3-wrong burner nozzle
4-lean fire 5- insufficient gas pilot or excessive gas pilot 6-water in the oil
What is the grade of light domestic fuel oil ? ...ANSWER...Grade 1 ( Number 1 )
How often should you test the operating control? ...ANSWER...Annually
How often should the testing and inspecting of the burner
component? ...ANSWER...Annually
