4B Power Engineering - Final - Nait Knowledge Checks
A light fuel oil flame should B
A impinge on the refractory, to
stabilize ignition.
B be bright yellow, with orange at the
tips of the flame.
C be predominantly blue, with
orange at the tips of the flame.
D be bright yellow, with smoke at the
tips of the flame.
The purpose of the pipe siphon C
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
Boilers should be warmed up C
A with maximum combustion air, to
prevent smoking
B rapidly, so the metal heats up faster
C slowly, to minimize differential
expansion and thermal shock
D using only the pilot burner.
, 4B Power Engineering - Final - Nait Knowledge Checks
The discharge pipe from a boiler C
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 To prevent leakage at the pipe joint
A modulating control steam heating C
boiler:
A Is always fully automatic
B Will have a narrow operating
pressure range
C Maintains a steadier boiler pressure
than multi-position control
D Will have a constant combustion air
flow rate
Which of the following is a desiccant C
used for dry layup?
A Silicone Gel
B Lime soda
C Quick lime
D Soda ash
The prime importance of boiler C
fittings is:
A Economics
B To satisfy regulations
C Safety & efficiency
D Convenience
, 4B Power Engineering - Final - Nait Knowledge Checks
If a new boiler is not boiled out D
correctly, the result may be:
A Refractory damage
B Excessive waterside corrosion
C Excessively high water circulation
rates
D Foaming
Because natural gas is colourless and D
odourless, ___________ is added to the
gas so that it is easier to detect a leak.
A fluorescent dye
B propane
C an irritant
D mercaptan
One purpose of the small valve on C
top of the shell of most boilers, which
is not required by code, is to:
A allow water into the boiler when
the boiler is being drained or cooled
preventing the formation of a
vacuum.
B allow water to escape before the
steam stop valve is opened during
the warm-up period.
C allow air to escape from the boiler
when the boiler is being filled with
water.
D allow air into the boiler when the
boiler is being filled with water.
, 4B Power Engineering - Final - Nait Knowledge Checks
Mechanical chart recorders C
A require regular replacement of
paper and ink.
B need their charts replaced each
month.
C require constant winding of their
clock mechanisms.
D are used so regular readings do
not need to be taken.
Tubular gauge glasses: A
A Are suitable for pressures up to
about 3000 kPa
B Are made of glass, in order to
resistant boiler alkalinity
C Indicate the level more accurately
than other forms of water level
indication
D Can only be installed on low-
pressure boilers
A light fuel oil flame should B
A impinge on the refractory, to
stabilize ignition.
B be bright yellow, with orange at the
tips of the flame.
C be predominantly blue, with
orange at the tips of the flame.
D be bright yellow, with smoke at the
tips of the flame.
The purpose of the pipe siphon C
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
Boilers should be warmed up C
A with maximum combustion air, to
prevent smoking
B rapidly, so the metal heats up faster
C slowly, to minimize differential
expansion and thermal shock
D using only the pilot burner.
, 4B Power Engineering - Final - Nait Knowledge Checks
The discharge pipe from a boiler C
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 To prevent leakage at the pipe joint
A modulating control steam heating C
boiler:
A Is always fully automatic
B Will have a narrow operating
pressure range
C Maintains a steadier boiler pressure
than multi-position control
D Will have a constant combustion air
flow rate
Which of the following is a desiccant C
used for dry layup?
A Silicone Gel
B Lime soda
C Quick lime
D Soda ash
The prime importance of boiler C
fittings is:
A Economics
B To satisfy regulations
C Safety & efficiency
D Convenience
, 4B Power Engineering - Final - Nait Knowledge Checks
If a new boiler is not boiled out D
correctly, the result may be:
A Refractory damage
B Excessive waterside corrosion
C Excessively high water circulation
rates
D Foaming
Because natural gas is colourless and D
odourless, ___________ is added to the
gas so that it is easier to detect a leak.
A fluorescent dye
B propane
C an irritant
D mercaptan
One purpose of the small valve on C
top of the shell of most boilers, which
is not required by code, is to:
A allow water into the boiler when
the boiler is being drained or cooled
preventing the formation of a
vacuum.
B allow water to escape before the
steam stop valve is opened during
the warm-up period.
C allow air to escape from the boiler
when the boiler is being filled with
water.
D allow air into the boiler when the
boiler is being filled with water.
, 4B Power Engineering - Final - Nait Knowledge Checks
Mechanical chart recorders C
A require regular replacement of
paper and ink.
B need their charts replaced each
month.
C require constant winding of their
clock mechanisms.
D are used so regular readings do
not need to be taken.
Tubular gauge glasses: A
A Are suitable for pressures up to
about 3000 kPa
B Are made of glass, in order to
resistant boiler alkalinity
C Indicate the level more accurately
than other forms of water level
indication
D Can only be installed on low-
pressure boilers
