A.discharges into a gradually widening channel
B.has stationary diffuser vanes
C.produces no kinetic energy
D.All of the above are true
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A.Piston pump
B.Screw pump
C.Diffuser pump
D.Water-ring pump
A.pump entry branch
B.outlet pipe
C.impeller
D.None of the above is true
A.to fill 2 tanks at the same time
B.to use pump at a higher pressure
C.to return liquid to suction side if discharge valve is closed
D.All of the above are true
A.injector
B.positive displacement
C.centrifugal
D.centripetal
A.injector pumps
B.positive displacement pumps
C.centrifugal pump
D.centripetal pumps
A.the mechanical seal
B.packed stuffing boxes
C.either A or B
D.neither A nor B
As for a hydraulic vane pump, which of the following is in contact with the vanes during working: ()
(1)the rotor
(2)the pump shaft
(3)the external surface of the housing
A.(1) only
B.(2) only
C.(1) and (2)
D.(1),(2)and(3)
A.circular
B.elliptical
C.rectangular
D.hexagon
A.suction
B.exhaust
C.pressure
D.discharge
A.draw the liquid in;force the liquid out
B.force the liquid out;draw the liquid in
C.suction;draw
D.deliver;outlet
最新试题
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