B-03: Boiler Safety Devices Flashcards
(20 cards)
During the start-up of a fully automatic boiler, the main burner safety shut-off valve (SSOV):
A. Must be opened before the ignition transformer energizes
B. Can be opened any time during the start-up sequence
C. Should be opened as soon as the pilot valve opens
D. Must be closed before pilot ignition
D. Must be closed before pilot ignition
The safety valves on a boiler are set to open at 1380 kPa. The boiler MAWP is 1380 kPa. How much higher can the boiler pressure rise above 1380 kPa, if it is fired at full capacity with the steam outlet valve closed?
A. 37.5 kPa
B. 41.4 kPa
C. 0 kPa
D. 82.8 kPa
D. 82.8 kPa
The prime importance of boiler fittings is:
A. Economics
B. To satisfy regulations
C. Saftey & Efficiency
D. Convenience
C. Safety & Efficiency
What is the advantage of an electric probe switch?
A. Scale or sediment do not form on the probe
B. It’s complex construction
C. It has no moving parts
D. Mechanical failure is not eliminated
C. It has now moving parts
According to ASME IV, the scale of a pressure gauge for a steam boiler shall be graduated to not less than:
A. 100 to 300 kPa
B. 200 to 414 kPa
C. 2500 to 3000 kPa
D. 125 to 325 kPa
B. 200 to 414 kPa
What is one of the purposes of the drum vent valve on steam power boilers?
A. Allows water to escape before the steam stop valve is opened during the warm-up period
B. Allows water into the boiler when the boiler is being drained or cooled to prevent a vaccumm from forming
C. Allows air into the boiler when the boiler is being filled with water
D. Allows air into the boiler when the boiler is being drained or cooled.
D. Allows air into the boiler when the boiler is being drained or cooled
When installing a gauge siphon, it is important to:
A. Keep the siphon dry
B. Install it downstream of an inspectors test connection
C. First fill it with water
D. Install it as close to the boiler as possible
C. First fill it with water
A flame rod:
A. Is used in combination with a photocell
B. Is used only for oil fired burners
C. Forms an electric circuit with the rod, flame and burner
D. Develops a high resistance in the presence of a flame
C. Forms an electric circuit with the rod, flame and burner
ASME-BPVC.I, Part PG-72.4 permits set pressure adjustments outside of approximately what percentage range?
A. 1%
B. 7%
C. 3%
D. 5%
D. 5%
If a high pressure boiler is on high fire with the main steam stop valve closed, the safety valves must ensure that the:
A. Boiler pressure does not exceed the maximum allowable working pressure of the boiler by more than 6%.
B. Boiler pressure does not exceed the set point of the safety valve
C. Steam pressure does not exceed the maximum allowable working pressure of the boiler
D. Boiler pressure does not exceed the hydrostatic test pressure
A. Boiler pressure does not exceed the maximum allowable working pressure of the boiler by more than 6%.
A gauge glass shows the level of a clear, colourless liquid as very dark, is the ______ gauge glass.
A. Bi-colour
B. Tubular
C. Reflex
D. Flat
C. Reflex
A high pressure boiler with a heating surface not exceeding ______ in area can have only a single safety valve.
A. 47 m2
B. 36 m2
C. 28 m2
D. 19 m2
A. 47 m2
A flame failure device is unresponsive to:
A. Ultraviolet light
B. Infra-red light
C. Visible light
D. Fuel flow
D. Fuel flow
A low water fuel cutoff on an unattended steam boiler shall be installed so that:
A. It cannot be be rendered inoperative
B. It starts the feed water pump
C. It can be isolated if it is not required
D. It shuts down the burner when the water level falls below the lowest visible part of the gauge glass
A. It cannot be rendered inoperative
A thermocouple:
A. Consists of two similar wires
B. Produces an electric signal
C. Senses infrared light from the flame
D. Is made of several thermopiles connected in series
B. Produces an electric signal
Like oh-off control, what does a multi-position control do?
A. Allows the burner to be either On or Off
B. Increases heat losses caused by repeated purging
C. Permits finer control of the boiler steam pressure of temperature
D. Requires three pressure controls
C. Permits finer control of the boiler steam pressure or temperature
Where must the drain valves or cocks be installed in a boiler ?
A. On the middle gauge glass fitting
B. In the lower gauge glass fitting
C. On all gauge glass fittings
D. On the upper gauge glass fitting
B. On the lower gauge glass fitting
The purpose of the pipe siphon installed between the boiler and the pressure gauge is to prevent:
A. Air from entering the gauge
B. Water from entering the gauge
C. Hot steam from entering the gauge
D. Air from entering the boiler
C. Hot steam from entering the gauge
Which of the following is NOT a category into which ASME-BPVC.I and ASME-B31.1 divide high pressure plant piping?
A. Boiler non-proper internal piping
B. Non-boiler external piping
C. Boiler proper piping
D. Boiler external piping
A. Boiler non-proper internal piping
A steam boiler is regularly blown off in order to:
A. Clean the soot and carbon out of the firebox and tubes
B. Lower the operating water level in the boiler
C. Discharge sediment from the boiler
D. Test the rated relieving capacity of the safety valves fitted to the boiler
C. Discharge sediment from the boiler
