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Centrifugal Pumps and its principles


Quiz Questions

1.Centrifugal pumps basically consist of a stationary pump casing and an impeller mounted on a rotating shaft.
True
False
2. Figure 3 represents a ________________ .
Centrifugal pump
Centrifugal pump diffuser
3.The purpose of the impeller is to increase the efficiency of the centrifugal pump by allowing a more gradual expansion and less turbulent area for the liquid to reduce in velocity.
True
False
4.A single-suction impeller allows liquid to enter the center of the blades from _______________.
Only one direction
Both sides simultaneously
5.Figure 5 represents _______________ .
Open, Semi-Open, and Enclosed Impellers
Single Suction and Double Suction Impellers
6.Impellers can be open, semi-open, or enclosed. The open impeller is constructed with a circular plate (the web) attached to one side of the blades. The semi-open impeller consists only of blades attached to a hub.
True
False
7.In a _____________________, the liquid enters at the center of the impeller and is directed out along the impeller blades in a direction at right angles to the pump shaft.
Radial flow pump
Axial flow pump
8.Figure 10 represents _____________.
Centrifugal Pump Components
Multi-Stage Centrifugal Pump
9.A lantern ringis a perforated hollow ring located near the center of the packing box that receives relatively cool, clean liquid from either the discharge of the pump or from an external source and distributes the liquid uniformly around the shaft to provide lubrication and cooling.
True
False
10.Mechanical seals consist of two basic parts, a rotating element attached to the pump shaft and a stationary element attached to the pump casing.
True
False
11.One of the simplest types of _____________ is the stuffing box.
Shaft seal
Mechanical seal
12.Wearing ringsare replaceable rings that are attached to the impeller and/or the pump casing to allow a small running clearance between the impeller and the pump casing without causing wear of the actual impeller or pump casing material.
True
False
13.Axial flow pumps are sometimes called propeller pumps because they operate essentially the same as the propeller of a boat.
True
False
14.An impeller increases the efficiency of a centrifugal pump by allowing a more gradual expansion and less turbulent area for the liquid to slow as the flow area expands.
True
False
15.The volute collects the liquid discharged from the impeller at high velocity and gradually causes a reduction in fluid velocity by increasing the flow area, converting the velocity head to a static head.
True
False