Pumps
A
mechanical device or machine that lift liquids against the force of
gravity or remove exhaust gases from closed vessels. It is used to
lift liquid from a source below the pump to a higher
elevation, to move liquid from one location to another, to move
liquid from a low pressure area to a higher pressure area. The
machine used to withdraw air or any gases from a closed vessel is
also classified as a pump.
Pumps
are classified with respect to their construction or the service for
which they are designed. The three groups of pumps are
centrifugal, reciprocating and rotary.
Centrifugal
Pumps
This
pump derived its name from the type of force that this design
of pump utilizes. Centrifugal force acts on a body moving in a
circular path, tending to force it farther from the center of the
circle. Inside the body of a centrifugal pump, the liquid is
force to revolve and so generates the force that enable this style of
pump to develop pressure and move liquids. It compose of
blades or vanes called the impeller and the surrounding case called
housing or volute.
Centrifugal
pumps are made in a great variety of types, styles and sizes
to suit application requirements and operating conditions. A basic
design difference between pumps is the number of stages. Pumps
with one impeller are classified as single-stage pumps and
those with two or more are called multistage pumps.
