A centrifugal pump is a
rotodynamic pump that uses a rotating impeller to create
flow by the addition of energy to a fluid. Centrifugal pumps
are commonly used to move liquids through piping. The fluid
enters the pump impeller along or near to the rotating axis
and is accelerated by the impeller, flowing radially outward
into a diffuser or volute chamber (casing), from where it
exits into the downstream piping. Centrifugal pumps are used
for large discharge through smaller heads.
Like most pumps, a centrifugal pump
converts mechanical energy from a motor to energy of a
moving fluid; some of the energy goes into kinetic energy of
fluid motion, and some into potential energy, represented by
a fluid pressure or by lifting the fluid against gravity to
a higher level.
Vertical centrifugal pumps :
Vertical centrifugal pumps are also
referred to as cantilever pumps. They utilize a unique shaft
and bearing support configuration that allows the volute to
hang in the sump while the bearings are outside of the sump.
This style of pump uses no stuffing box to seal the shaft
but instead utilizes a "throttle Bushing". A common
application for this style of pump is in a parts washer.
Multistage centrifugal pumps :
A centrifugal pump containing two or more
impellers is called a multistage centrifugal pump. The
impellers may be mounted on the same shaft or on different
shafts.
If we need higher pressure at the outlet we can connect
impellers in series.
If we need a higher flow output we can connect impellers in
parallel.
All energy added to the fluid comes from the power of the
electric or other motor force driving the impeller.
