A.loss of second stage vacuum
B.contamination of the distillate
C.lower feed inlet temperature
D.contamination of the second stage condenser
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A.total head
B.discharge head
C.net positive suction head
D.suction head
A.slide block
B.tilting box
C.pintle
D.reaction ring
A.Liquids with different viscosities will always have the same specific gravity
B.Liquids with different viscosities will never have the same specific gravity
C.Viscosity and specific gravity are directly proportional
D.Viscosity and specific gravity are not related in that one does not define or limit the other
A.stored at temperatures below 60 degrees Fahrenheit
B.charged into a system having copper fittings
C.allowed to mix with compressor oil
D.exposed to an open flame or hot surface
A.acid formation
B.sludge formation
C.ice in the expansion valve
D.All of the above
A.superheated outside the system
B.in contact with an open flame
C.heated to the boiling point
D.All of the above
A.Variable volumes can be obtained with gear pumps only by variation of the pump drive speed
B.A radial piston pump houses sliding pistons in a stationary cylinder block through which passes a rotating pintle or ported shaft
C.The amount of fluid displaced per revolution of an axial piston rotary pump is dependent on the angle formed between the cylinder block and valve plate
D.All of the above
A.transmit the rudder angle to the bridge indicator
B.prevent the control linkage from striking the stops when hard over
C.automatically purge all entrained air from the system
D.send hydraulic signals to the receiving unit
A.horizontally mounted
B.never fitted with intake filters
C.fitted with intercoolers
D.operated in an unloaded condition at all times
A.High pressure compressors are more efficient than low pressure compressors
B.Mechanical efficiency divided by compressor efficiency will equal the overall efficiency of the compressor unit
C.Two stage compressors are generally more efficient than single stage compressors
D.The volumetric efficiency is decreased in multistage compressors
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The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will ().
If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be ().
Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by ().
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its ().
One cause of high head pressure occurring in a refrigeration system can be ().
The general purpose of a heat exchanger is to ().
A salinity indicator is used to determine the ().
If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump ().
The usual symptoms of cavitation in a centrifugal pump is ().
A grease gun is generally used to lubricate a ().