_____ storage is preferable for boilers that are out of service for
an extended period of time or in locations where freezing
temperatures during the standby are expected. Correct Answers
Dry
______ is particularly harmful as it forms a very hard deposit on
turbine blades. Correct Answers Silica
________ happens when the pressure at any point inside a
centrifugal pump drops below the vapour pressure of the liquid
forming vapour bubbles and creates cavities in the liquid flow.
Correct Answers Cavitation
________ is the result of dissolved air or oxygen in the
feedwater. Correct Answers Pitting
_________ explosions occur when a pressure part of the boiler,
such as the steam drum, fails due to steam pressure or a
structural weakening of the metal. Correct Answers Pressure
_________ is any solid, liquid, or vaporous contaminants that
leave the boiler with the steam. Correct Answers Carryover
_________ testing involves the pressurization of a vessel with a
compressible gas, such as air or nitrogen, to determine if any
leaks are present. Correct Answers Pneumatic
,__________ _______ are leak-proof containers that have an
internal or external operating pressure. Correct Answers
Pressure vessels
__________ is the protrusion of weld metal beyond the weld toe
that covers the parent metal surface but has not fused to it.
Correct Answers Overlap
__________ is the term for spherical or tube like defects,
cavities, or voids caused by gases trapped inside the weld or
gases that have evolved to the surface. Correct Answers
Porosity
__________ takes precedence over the ASME BPVC, if a
conflict exists. Correct Answers CSA-B51
__________ uses area replacement as the basis for
reinforcement calculations. Correct Answers ASME BPVC
____________ is insufficient weld deposit, which results in a
depression or reduction in the thickness of a groove weld.
Correct Answers Underfill
_______________ is the only arc welding process capable of
welding all commercial ferrous and non-ferrous alloys. Correct
Answers Gas metal arc welding process (GMAW)
_________________ are solid non-metallic inclusions entrapped
below the surface in the weld metal, or more often, between
deposited weld metal and the base metal. Correct Answers Slag
inclusions
,A _________ feed system involves feeding the chemicals to the
boiler system at the most efficient injection points and at a
steady and continuous rate. Correct Answers Continuous
A 152.4 mm diameter piping system is 50 m long and contains
three elbows, two gate valves, one globe valve, and two tees. If
flow in the system is 75 L/s, calculate the friction head. Correct
Answers 8.364 m
A 203.2 mm diameter piping system is 75 m long and contains
three elbows, two gate valves, one globe valve, and five tees. If
flow in the system is 75 L/s, calculate the friction head. Correct
Answers 3.58 m
A centrifugal pump may be defined as a pump that uses
centrifugal force to impart energy to a fluid by giving the fluid
high _________ and then converting this into pressure. Correct
Answers Velocity
A centrifugal pump may be defined as a pump that uses
centrifugal force to impart energy to a fluid by giving the fluid
high _________ and then converting this into pressure. Correct
Answers Velocity
A chemical in a storage tank has a relative density of 7.60. What
is the equivalent head at the outlet of the tank where a pressure
gauge reads 250 kPa? Correct Answers : 3.35 m
, A hydrogen zeolite softener is used to remove the scale-forming
_____ without the formation of sodium bicarbonate. Correct
Answers Salts
A low gas pressure cut-off switch _______ the burner from
operating when the gas pressure in the supply line drops below
the pressure necessary to maintain a stable flame at the burner.
Correct Answers Prevents
A manufacturer specifies a required NPSH of 5 m for a certain
pump. To satisfy this requirement, what must the minimum
pressure be at the suction of the pump if the liquid being moved
is water at 120°C? (note Vf = 1.0603) Correct Answers 244.8
kPa
A pressure controller maintains a constant furnace pressure in a
boiler (at all loads) by adjusting the position of the ______
dampers. Correct Answers Induced draft
A pump is sitting at rest with its discharge valve open and the
pressure gauge showing 210 kPa. The total static head of the
pump in this situation is 11 m. If the pump takes suction from a
transfer tank located 4 m above it, what is the current level in the
transfer tank? The liquid is water at 42°C. Correct Answers :
6.59 m
A rapid increase in boiler load causes an immediate increase in
steam flow from the boiler, which creates a sudden _____ in the
boiler steam drum pressure. Correct Answers Drop