Archive for July 2017

Which one is NOT a cause for a relief valve in a heating boiler that is opening or spilling?

Which one is NOT a cause for a relief valve in a heating boiler that is opening or spilling?




A. Scale will form if the temperature of the heater is below 65C
B. Pressure in the supply line varies and at times exceeds the setting of the valve.
C. Relief valve is defective
D. Hot water system has become water logged


Answer: A

Who can repair a safety valve?

Who can repair a safety valve?




A. Boiler operator only if fully qualified to do so and authorization from the chief inspector
B. Manufacture
C. Authorized repair representative
D. All of the above




Answer: D

When should the pop test be performed?

When should the pop test be performed?




a. Weekly
b. Monthly
c. Semi-annually
d. Annual
e. Bi-weekly




Answer: D

The main advantage of the torsion bar safety valve is

The main advantage of the torsion bar safety valve is




A. Used on high pressure boilers
B. Machined to much finer specifications
C. More durable than safety valves
D. None of the above





Answer: B

Superheater safety valves has a exposed spring because?

Superheater safety valves has a exposed spring because?



A. Prevent high temperature from destroying the spring
B. Prevent high pressure from destroying the spring
C. Prevent the spring from corrosion
D. None of the above





Answer: A

A wire seal on a safety valve is installed by

A wire seal on a safety valve is installed by




a. a power engineer
b. boiler inspector
c. an engineer
d. an ASME-certified valve repair agency
e. an industrial insurance adjuster




Answer: B

Another name for the pop chamber is?

Another name for the pop chamber is?



A. Skirt chamber
B. Escape chamber
C. Huddling chamber
D. Spindle chamber
E. Spring chamber





Answer: C

Do not open the safety valve with the test lever:

Do not open the safety valve with the test lever:




a. If the valve is less than 2.5 cm inlet diameter
b. If the pressure is less than 75% working pressure
c. If there are more than two safety valves on the boiler
d. If the valve is not vented to the roof
e. After 9 PM in populated areas





Answer: B

To increase the opening pressure of a safety valve,:

To increase the opening pressure of a safety valve,:





a. Raise the blowdown ring
b. Increase spring compression
c. Reduce spring compression
d. Lower the blowdown ring
e. Add weights to the try lever




Answer: B

If a safety valve leaks after a try lever test, the operator should:

If a safety valve leaks after a try lever test, the operator should:




a. Plug the safety valve outlet
b. Reduce the boiler pressure
c. Operate the try lever several times to blow away foreign material
d. Fit a gag to the safety valve
e. Reduce boiler pressure and call the chief engineer





Answer: C

An operator should check that a boiler safety valve will open at its set pressure by:

An operator should check that a boiler safety valve will open at its set pressure by:




a. Asking the inspector to bring a master pressure gauge
b. Increasing the boiler pressure and noting the pressure at which the valve opens
c. Putting a piece of pipe over the lifting lever and lifting the valve off its seat when the set pressure is reached
d. Using air pressure during a shutdown to raise the pressure in the boiler until the set pressure is reached
e. Performing a hydrostatic test on the boiler





Answer: B

A safety relief valve is similar to a safety valve except that it:

A safety relief valve is similar to a safety valve except that it:




a. Does not have a blowdown ring or bottom guides
b. Must have greater blowdown
c. May have an isolation valve placed between it and the pressure vessel
d. Must discharge directly to the atmosphere
e. Opens at a set temperature, rather than a set pressure





Answer: A

The discharge pipe from a boiler safety valve is supported independently of the safety valve:

The discharge pipe from a boiler safety valve is supported independently of the safety valve:



a. Because the steam drum cannot support the extra mass of the discharge pipe
b. So the discharge pipe can drain more easily
c. So the discharge pipe can expand without putting force on the safety valve
d. So the valve can be quickly and easily removed
e. To prevent leakage at the pipe joint




Answer: C

When performing a safety valve pop test, one of the first things to do is:

When performing a safety valve pop test, one of the first things to do is:




a. Notify the boiler inspector
b. Verify the accuracy of the boiler steam pressure gauge
c. Notify the chief engineer
d. Check the blowdown of the safety valve
e. Check the popping pressure




Answer: B

The set pressure of a safety valve may only be adjusted by:

The set pressure of a safety valve may only be adjusted by:





a. a power engineer
b. a plumber
c. an engineer
d. an ASME-certified valve repair agency
e. an industrial insurance adjuster





Answer: D

The test lever on a safety valve must not be used unless the boiler:

The test lever on a safety valve must not be used unless the boiler:





a. Is at maximum operating pressure
b. Has no load on it
c. Inspector approves it
d. Pressure is at least 75% of the valve popping pressure
e. Is at the popping pressure of the safety valve





Answer: D

The purpose of the spring in a safety valve is to:

The purpose of the spring in a safety valve is to:





a. Help open the testing lever
b. Pull open the valve at blowing pressure
c. Adjust the pressure setting of the valve
d. Adjust the blow down of the valve
e. Hold down the disc on the seat




Answer: E

Testing a safety valve on a boiler by pulling the try-lever

Testing a safety valve on a boiler by pulling the try-lever



a. Ensures the popping pressure is correct
b. Indicates that valve capacity is adequate
c. Ensures the closing pressure is correct
d. Takes approximately two seconds
e. Ensures the valve is free to operate





Answer: E

If a boiler was fired with the main steam stop valve closed, the safety valves should ensure that the:

If a boiler was fired with the main steam stop valve closed, the safety valves should ensure that the:





a. Pressure cannot exceed the maximum working pressure by more than 6%.
b. Water glass will not burst with the pressure.
c. Fuel cut-off will operate.
d. Pressure cannot exceed the maximum working pressure by more than 3%.
e. Pressure is never more than the hydrostatic test pressure.




Answer: A

Safety valves "pop" open because the pressure of the steam:

Safety valves "pop" open because the pressure of the steam:




a. Acts upon a blow down ring
b. Acts upon a huddling chamber
c. Acts upon a larger area as soon as the valve opens
d. Increases due to the discharge ports
e. Decreases the force created by the spring




Answer: C

If the safety valves on a boiler are undersized, the boiler pressure may:

If the safety valves on a boiler are undersized, the boiler pressure may:



a. Rise 5% above the maximum allowable working pressure MAWP
b. Not rise more than 15% above the MAWP
c. Remain at the MAWP
d. Rise to 6% above the MAWP
e. Rise more than 6% above the MAWP





Answer: E

Which one is NOT a disadvantage of the FBC system?

Which one is NOT a disadvantage of the FBC system?





A. Carryover
B. High power requirements for combustion air
C. Large space required for installation
D. Poor combustion control at low operating rates



Answer: C

Less maintenance is required on the FBC because?

Less maintenance is required on the FBC because?



A. Slag is eliminated
B. Clinkers is eliminated
C. Soot-blowers are not required
D. Dry combustion is easier to dispose of
E. All of the above





Answer: E

What is an advantage of the FBC?

What is an advantage of the FBC?




A. Flexibility of fuel choices
B. Less maintenance
C. Smaller plant size
D. Less fuel feed
E. All of the above





Answer: E

AFBC has two sub classes which are?

AFBC has two sub classes which are?




A. Pressurized bed, circulating bed
B. Bubbling bed, fluidized bed
C. Fluidized bed, pressurized bed
D. Bubbling bed, circulating bed
E. None of the above




Answer: D

A design disadvantage of a pressurized fluidized bed furnace is:

A design disadvantage of a pressurized fluidized bed furnace is:




a. Erosion and/or corrosion/fouling of turbine blades may occur
b. A wide range of fuels cannot be used
c. A great deal of maintenance is required
d. Fuel preparation is very complex
e. The boiler is too compact for ease of cleaning



Answer: A

Large "clinkers" are not produced in fluidized bed furnaces because of:

Large "clinkers" are not produced in fluidized bed furnaces because of:



a. Lower furnace temperatures
b. Fast fluidization air movement
c. The kind of fuel being burned
d. FBC boilers can only burn fuel with low ash fusion temperatures
e. The very high furnace temperatures




Answer: A

In order to get maximum heat transfer in a bubbling bed furnace, it is necessary to:

In order to get maximum heat transfer in a bubbling bed furnace, it is necessary to:




a. Increase the fuel consumption per hour
b. Ensure that the boiler tubes are covered by the expanded bed
c. Line the floor and ceiling of the furnace with steel plates
d. Add fuel gas to the regular fuel being burned
e. Operate the sootblowers more frequently






Answer: B

In an atmospheric fluidized bed boiler, the combustion air pressure is typically 25 cm of water at the FD fan, 16 cm of water at the base of the active bed and _____ at the top of the combustion mass:

In an atmospheric fluidized bed boiler, the combustion air pressure is typically 25 cm of water at the FD fan, 16 cm of water at the base of the active bed and _____ at the top of the combustion mass:



a. Boiler pressure
b. Negative 16 cm of water
c. Negative pressure
d. Atmospheric pressure
e. Absolute pressure





Answer: D

Limestone, when added to a fluidized bed boiler

Limestone, when added to a fluidized bed boiler



a. Lowers the combustion bed temperature
b. Acts as a de-sulphuring agent
c. Absorbs NOx
d. Reduces greenhouse gas emissions
e. Reduces emissions of ozone depleting substances





Answer: B
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