2. 2.1 Introduction
• Pump is a mechanical device used to move
fluid from one point to another or is a
mechanical device used to convert mechanical
energy to hydraulic energy.
• Further it is used to:
• elevate fluid
• pressurize fluid
• impart kinetic energy to fluid
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10. Components of a centrifugal pump
1.Impeller (or rotor)
• Main part
• Used to rotate and finally cause to the liquid to leave the
impeller by centrifugal force
• Classification:
a) Closed the shrouded impeller
b) Semi closed impeller
c) opened impeller
• Open semi closed closed impeller
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11. Components of a centrifugal pump (continued)
• a) Closed/shrouded impeller
Shrouds are on both sides between of which plain
(radial) or curved (mixed flow with second curve at
impeller eye) )vanes are inserted. These impellers
have passage for water entry called impeller eye.
Used to pump pure liquid like water, oil, acid. alkali,
etc. The material should be resistant against the
reactions of the material handled.
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12. Components of a centrifugal pump (continued)
• b) Semi closed/opened impeller
Vanes are fixed on one shroud only, has less
number of vanes with more length to avoid
clogging. Used to pump liquids containing muck
or debris up to some extent only such as sewage
water, paper pulp, etc.
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13. Components of a centrifugal pump (continued)
• c) opened impeller
Vanes are directly fixed on web. Used to pump
slurry or liquids having large solid particles like
sand, pebbles. Perform very rough job therefore
should be resistant against wear and impact.
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18. Components of a centrifugal pump (continued)
• 3-Suction pipe
It is a pipe, whose upper end is connected with the pump on
suction side, and lower end is submerged in the liquid in a
sump. The lower end is fitted with foot valve and strainer.
Due to small suction pipe length, friction loss is insignificant.
However it is important in that how far liquid is uniformly
entering the impeller eye.
• 4-Delivery pipe
The delivery pipe starts from the outlet flange of the pump
and end at the supply end or reservoir as the case may be.
Just after the outlet flange a sluice valve and a non-return
valve is fitted.
• 5-Prime mover
Generally an electric motor directly coupled with pump. A
diesel engine with belting system is also used.
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19. 2.4 Centrifugal pump arrangements
• Can be arranged with either horizontal or a vertical shaft depending upon type of
application, type of drive arrangement and other requirements. But vertical turbine
pump is the one which has been specifically developed for vertical operation.
Considering space limitation and better efficiency, vertical pumps are now widely
used .Horizontal pumps are replaced by vertical pumps
• Horizontal centrifugal pump
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