Answer Posted / bala10286
in case of positive displacement pumps (ex:reciprocating
pump) the piston or mechanical member directly creates the
vacuum or lower pressure such that the water or liquid is
sucked in..
in case of centrifugal pumps...the impeller just
displaces the water due to the centrifugal force..as the
water at center of impeller is displaced to the
casing..partial vacuum gets created at the eye of impeller
and hence suction of new water takes place..
if there is no water around impeller..only air is
present and it cant be displaced by the pump impeller as air
is compressible..the pump impeller is designed to handle
water or liquid.. therefore to remove the air and fill the
casing with water the priming is carried out..
there is no need of priming if there is an foot
valve and its working well...
| Is This Answer Correct ? | 17 Yes | 2 No |
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