MD STATIONARY ENGINEER TEST PAPER 2025/2026
QUESTIONS WITH ANSWERS GRADED A+
✔✔How do you protect a steam boiler? - ✔✔Safety valve
✔✔How to you protect a pressure vessel? - ✔✔Pressure relief valve
✔✔How do you protect a hot water boiler? - ✔✔Pressure relief valve
✔✔What gages are on a steam boiler? - ✔✔Water gage glass and pressure gage
✔✔Methods used to control the temperature of a superheater? - ✔✔Bypass damper -
spray-type desuperheater - attemperator - condenser - tilting burner - flue gas
recirculation
✔✔What chemical would you use to prevent hard scale from forming in the boiler
tubes? - ✔✔Disodium phosphate and trisodium phosphate
✔✔What chemical compounds in water cause permanent hardness? - ✔✔Calcium
sulfate and magnesium sulfate
✔✔What factors must be taken into consideration when choosing a control for a boiler?
- ✔✔6 factors 1. Steam pressure 2. Furnace pressure and draft 3. air pressure and flow
4. feed water pressure and flow 5. Flue gas flow & composition 6. proper ignition &
burner - flame control
✔✔How many safety controls shut down a boiler when an unsafe condition occurs? -
✔✔7 controls 1. Pressure limit or temperature 2. Low water fuel cutoffs 3. Flame failure
safeguard systems 4. Automatic ignition controls 5. oil and gas fuel shutoffs/valve
controls 6. air and fuel pressure interlock controls 7. feed water regulating controls
✔✔In a steam generating system what is blamed on chemical treatment but is in fact
part of a boiler design? - ✔✔Poor circulation
✔✔Class A Fires??? - ✔✔Wood - sawdust - paper - rags
✔✔Class B Fires?? - ✔✔Flammable liquids - oils - tars and gasses
✔✔Class C Fires?? - ✔✔Electrical equipment
✔✔What is the minimum clearance required when a boilers capacity is 5 000btus hr
over 1000sq ft heating surface or an imput over 5 000 000 btus hr? - ✔✔7 feet
,✔✔Under what code are oil fired boilers and their control systems covered? - ✔✔O.F.B
726
✔✔A data plate has what information?? - ✔✔manufacturer - model serial number -
stamp of approval
✔✔When working in a boiler work permits should be aquired when? - ✔✔For Each Shift
✔✔ASME code requires that a LWCO control be tested by evaporation how often?? -
✔✔Monthly
✔✔ASME CSD1 requires the main gas burner to have what? - ✔✔2 manual shutoff
valves. pg 81 1004.1 code book
✔✔A HYDROSTATIC test is done at what pressure? - ✔✔1.5 times the MAWP or 50%
over MAWP
✔✔How many low water cutoff are needed per code on a hot water system? - ✔✔One
LWCO is needed when the boiler input is greater than 400 000 btus
✔✔What gages are on a steam boiler? - ✔✔pressure gage - water gage glass
✔✔What gages are on a HW boiler? - ✔✔pressure - Temp
✔✔Name three types of low water cutoffs. - ✔✔1. float magnetic (rod to magnet to
mercury switch) 2. Float linkage- link to mercury switch 3. Submerged electrode- water
✔✔Boilers having more than 500square feet of heating surface should have how many
means of feed water? - ✔✔2
✔✔Types of FEEDWATER REGULATORS - ✔✔1.Thermostatic mechanical regulator 2.
Thermostatic fluid style 3. Float operated style
✔✔Name two types of commonly used feedwater pumps - ✔✔Injector and Inspirator
✔✔What piping arrangment is used to return condensate from steam lines and steam
seperators? - ✔✔HOLLYLOOP
✔✔What would happen if high temp liquid passes through a centrifugal pump? -
✔✔WIRE DRAWING
✔✔A multi stage pump can be either __________ or_______ ? - ✔✔Volute or Diffuser
,✔✔To prevent cavitation most pumps are stamped with the ____ _______ _______
____ ? - ✔✔NET POSITIVE SUCTION HEAD
✔✔What are two types of condensate return systems?? - ✔✔a.) Mechanical Return ;
uses steam traps and pumps to aid return b.) Gravity Return System : uses gravity
✔✔TO PREVENT THE SUPERHEATER FROM OVERHEATING ON START UP
WHAT SHOULD YOU DO - ✔✔EITHER FLOOD THE TUBES WITH WATER OR THE
SUPERHEATER SHOULD BE VENTED TO THE ATMOSPHERE BY A FREE BLOW
VALVE UNTIL THE BOILER GOES ON LINE.
✔✔What device acts as a check valve in both directions and keeps the pump primmed?
- ✔✔FOOT VALVES ARE USED ON PUMPS UNDER SUCTION PRESSURE AND
PREVENT FLOW ON SUCTION LINE
✔✔WHAT PUMP HAS A WATER PISTON DIRECTLY CONNECTED TO A STEAM
DRIVEN PISTON VIA A ROD? - ✔✔RECIPRICATING
✔✔What causes a piston type trap to open? - ✔✔cold condensate (on test the steam
psi drop and temp drop was used)
✔✔Quickly opening a steam valve will cause _______ ________ . - ✔✔water hammer
✔✔What mechanical device removes scale from a watertube boiler? - ✔✔a tube turbine
✔✔What causes blistering? - ✔✔A slag inclusion forming a lamination at the time the
plate was rolled in the steel mill and it's actually a seperation of metal from the shell
plate caused by impurities rolled into the shellplate when it was formed.
✔✔To internally remove oxygen from the boiler use______ ________ . - ✔✔Sodium
Sulfite
✔✔A positioning control system is used on a ______ ________ - ✔✔a process boiler
✔✔A saybolt universal is a - ✔✔measurement of viscosity
✔✔Creep gets worse with _______________ __________ - ✔✔elevated temps
✔✔What type of valve WOULD NOT be a good choice if sediment were present -
✔✔GLOBE
✔✔How many btus does it take to take 10 lbs of steam from 40 to 41 degrees - ✔✔10
btus 1btu=1lb
, ✔✔What is it called when you let a peice of equipment fail before you repair/replace it? -
✔✔Breakdown maintenance
✔✔What percent of blistering or buldging is ok? - ✔✔2%
✔✔What kind of boiler are staybolts found on? - ✔✔Fire tube boilers
✔✔A 8 foot length of tube or shell can take up to ___% sag or bend and still be used
without replacing? - ✔✔2%
✔✔What does a low water cutoff do in a low water condition? - ✔✔Shuts off fuel supply
✔✔What is the first indication of a low water condition - ✔✔A red hot crown sheet
✔✔If a boiler exceeds 100psi it must have how many blowdowns? - ✔✔2
✔✔What is the appropriate test for checking porosity of the metal? - ✔✔PULSE ECHO (
A TYPE OF ULTRASONIC)
✔✔What chemicals are used to combat corrosion? - ✔✔Sodium Sulfite; hydrazine;
catalied hydrazine
✔✔If your boiler water has a PH of .5 what compound type do you add to neutralize it? -
✔✔BASES - THEY REACT WITH ACIDS TO FORM A SALT
✔✔What level of deionized water alkalinityis permitted for a 600 psi boiler? - ✔✔250
PPM
✔✔What can oxygen cause in a system - ✔✔PITTING CORROSION
✔✔In a vertical boiler where is the first place to check for thinning tubes? - ✔✔WATER
LEGS especially at the bottom or on the combustion side at the upper ends of the
tubes.
✔✔What produces soft scale? - ✔✔Calcium and magnesium carbonate and magnesium
clorine
✔✔Hideout in a boiler causes what to precipitate? - ✔✔Sodium phosphate
✔✔What is main cause of a generating tube failure? - ✔✔overheating at the lower tubes
due to scale sludge and poor circulation
QUESTIONS WITH ANSWERS GRADED A+
✔✔How do you protect a steam boiler? - ✔✔Safety valve
✔✔How to you protect a pressure vessel? - ✔✔Pressure relief valve
✔✔How do you protect a hot water boiler? - ✔✔Pressure relief valve
✔✔What gages are on a steam boiler? - ✔✔Water gage glass and pressure gage
✔✔Methods used to control the temperature of a superheater? - ✔✔Bypass damper -
spray-type desuperheater - attemperator - condenser - tilting burner - flue gas
recirculation
✔✔What chemical would you use to prevent hard scale from forming in the boiler
tubes? - ✔✔Disodium phosphate and trisodium phosphate
✔✔What chemical compounds in water cause permanent hardness? - ✔✔Calcium
sulfate and magnesium sulfate
✔✔What factors must be taken into consideration when choosing a control for a boiler?
- ✔✔6 factors 1. Steam pressure 2. Furnace pressure and draft 3. air pressure and flow
4. feed water pressure and flow 5. Flue gas flow & composition 6. proper ignition &
burner - flame control
✔✔How many safety controls shut down a boiler when an unsafe condition occurs? -
✔✔7 controls 1. Pressure limit or temperature 2. Low water fuel cutoffs 3. Flame failure
safeguard systems 4. Automatic ignition controls 5. oil and gas fuel shutoffs/valve
controls 6. air and fuel pressure interlock controls 7. feed water regulating controls
✔✔In a steam generating system what is blamed on chemical treatment but is in fact
part of a boiler design? - ✔✔Poor circulation
✔✔Class A Fires??? - ✔✔Wood - sawdust - paper - rags
✔✔Class B Fires?? - ✔✔Flammable liquids - oils - tars and gasses
✔✔Class C Fires?? - ✔✔Electrical equipment
✔✔What is the minimum clearance required when a boilers capacity is 5 000btus hr
over 1000sq ft heating surface or an imput over 5 000 000 btus hr? - ✔✔7 feet
,✔✔Under what code are oil fired boilers and their control systems covered? - ✔✔O.F.B
726
✔✔A data plate has what information?? - ✔✔manufacturer - model serial number -
stamp of approval
✔✔When working in a boiler work permits should be aquired when? - ✔✔For Each Shift
✔✔ASME code requires that a LWCO control be tested by evaporation how often?? -
✔✔Monthly
✔✔ASME CSD1 requires the main gas burner to have what? - ✔✔2 manual shutoff
valves. pg 81 1004.1 code book
✔✔A HYDROSTATIC test is done at what pressure? - ✔✔1.5 times the MAWP or 50%
over MAWP
✔✔How many low water cutoff are needed per code on a hot water system? - ✔✔One
LWCO is needed when the boiler input is greater than 400 000 btus
✔✔What gages are on a steam boiler? - ✔✔pressure gage - water gage glass
✔✔What gages are on a HW boiler? - ✔✔pressure - Temp
✔✔Name three types of low water cutoffs. - ✔✔1. float magnetic (rod to magnet to
mercury switch) 2. Float linkage- link to mercury switch 3. Submerged electrode- water
✔✔Boilers having more than 500square feet of heating surface should have how many
means of feed water? - ✔✔2
✔✔Types of FEEDWATER REGULATORS - ✔✔1.Thermostatic mechanical regulator 2.
Thermostatic fluid style 3. Float operated style
✔✔Name two types of commonly used feedwater pumps - ✔✔Injector and Inspirator
✔✔What piping arrangment is used to return condensate from steam lines and steam
seperators? - ✔✔HOLLYLOOP
✔✔What would happen if high temp liquid passes through a centrifugal pump? -
✔✔WIRE DRAWING
✔✔A multi stage pump can be either __________ or_______ ? - ✔✔Volute or Diffuser
,✔✔To prevent cavitation most pumps are stamped with the ____ _______ _______
____ ? - ✔✔NET POSITIVE SUCTION HEAD
✔✔What are two types of condensate return systems?? - ✔✔a.) Mechanical Return ;
uses steam traps and pumps to aid return b.) Gravity Return System : uses gravity
✔✔TO PREVENT THE SUPERHEATER FROM OVERHEATING ON START UP
WHAT SHOULD YOU DO - ✔✔EITHER FLOOD THE TUBES WITH WATER OR THE
SUPERHEATER SHOULD BE VENTED TO THE ATMOSPHERE BY A FREE BLOW
VALVE UNTIL THE BOILER GOES ON LINE.
✔✔What device acts as a check valve in both directions and keeps the pump primmed?
- ✔✔FOOT VALVES ARE USED ON PUMPS UNDER SUCTION PRESSURE AND
PREVENT FLOW ON SUCTION LINE
✔✔WHAT PUMP HAS A WATER PISTON DIRECTLY CONNECTED TO A STEAM
DRIVEN PISTON VIA A ROD? - ✔✔RECIPRICATING
✔✔What causes a piston type trap to open? - ✔✔cold condensate (on test the steam
psi drop and temp drop was used)
✔✔Quickly opening a steam valve will cause _______ ________ . - ✔✔water hammer
✔✔What mechanical device removes scale from a watertube boiler? - ✔✔a tube turbine
✔✔What causes blistering? - ✔✔A slag inclusion forming a lamination at the time the
plate was rolled in the steel mill and it's actually a seperation of metal from the shell
plate caused by impurities rolled into the shellplate when it was formed.
✔✔To internally remove oxygen from the boiler use______ ________ . - ✔✔Sodium
Sulfite
✔✔A positioning control system is used on a ______ ________ - ✔✔a process boiler
✔✔A saybolt universal is a - ✔✔measurement of viscosity
✔✔Creep gets worse with _______________ __________ - ✔✔elevated temps
✔✔What type of valve WOULD NOT be a good choice if sediment were present -
✔✔GLOBE
✔✔How many btus does it take to take 10 lbs of steam from 40 to 41 degrees - ✔✔10
btus 1btu=1lb
, ✔✔What is it called when you let a peice of equipment fail before you repair/replace it? -
✔✔Breakdown maintenance
✔✔What percent of blistering or buldging is ok? - ✔✔2%
✔✔What kind of boiler are staybolts found on? - ✔✔Fire tube boilers
✔✔A 8 foot length of tube or shell can take up to ___% sag or bend and still be used
without replacing? - ✔✔2%
✔✔What does a low water cutoff do in a low water condition? - ✔✔Shuts off fuel supply
✔✔What is the first indication of a low water condition - ✔✔A red hot crown sheet
✔✔If a boiler exceeds 100psi it must have how many blowdowns? - ✔✔2
✔✔What is the appropriate test for checking porosity of the metal? - ✔✔PULSE ECHO (
A TYPE OF ULTRASONIC)
✔✔What chemicals are used to combat corrosion? - ✔✔Sodium Sulfite; hydrazine;
catalied hydrazine
✔✔If your boiler water has a PH of .5 what compound type do you add to neutralize it? -
✔✔BASES - THEY REACT WITH ACIDS TO FORM A SALT
✔✔What level of deionized water alkalinityis permitted for a 600 psi boiler? - ✔✔250
PPM
✔✔What can oxygen cause in a system - ✔✔PITTING CORROSION
✔✔In a vertical boiler where is the first place to check for thinning tubes? - ✔✔WATER
LEGS especially at the bottom or on the combustion side at the upper ends of the
tubes.
✔✔What produces soft scale? - ✔✔Calcium and magnesium carbonate and magnesium
clorine
✔✔Hideout in a boiler causes what to precipitate? - ✔✔Sodium phosphate
✔✔What is main cause of a generating tube failure? - ✔✔overheating at the lower tubes
due to scale sludge and poor circulation
