Some pumps use packing as sealing gland. The gland should be( )
A. slack enough to allow slight leakage of fluid
B. slightly blocked
C. brought up tight so as not to allow any leakage
D. fitted with a relief valve
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A mono-pump is a single-screw pump. That means it consists of( )rotor(s).
A. one
B. two
C. three
D. four
Gear pumps are of positive displacement type pumps because they discharge a near constanamount of liquid( )pressure.
A. depending on
B. in relative to
C. regardless of
D. because of
A reciprocating pump belongs to( )according to its working principle.
A. injector pumps
B. positive displacement pumps
C. centrifugal pumps
D. centripetal pumps
A/An( )pump is that where the volume of the pump chamber is alternately increased to draw the liquid in and then decreased to force the liquid out.
A. injector
B. positive displacement
C. centrifugal
D. centripetal