Page 191 - Know and Understand Centrifugal Pumps

Know and Understand Centrifugal Pumps

and space of the complicated camshaft mechanisms and gears were
eliminated. On land, the electric motor opened the door to the first
practical centrifugal pump.
The practical centrifugal pump was a significant invention. The rotary
motor (whether steam turbine, internal combustion or electric)
resolved the issue of velocity. The rotary motor permitted the pumping
of tremendous quantities of fluid with relatively small pump housing,
compared to its reciprocating sister. The pumping action begins again
with each revolution of the spinning impeller, instead of each slow cycle
of the piston and rod.

There is ar iother important difference between the centrifugal pump and its
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reciprocating sister aitnougn it is not consiaerea a weakness. try aesign, the TIOW or
r.
the reciprocatini g pump has to pulse, similar to the beati ng of the human heart. The
centrifugal pum p with the rotary motor and impeller hi 3s a constant flow without
pulsing. With advallcc, LcLllllu luyy, iuiaiy ~u~illvc Ul+lacement pumps have been
developed, and when mated to electric motors can give a constant flow without
pulsing.

Synthetic fibers

Since the beginning of time, water, either fresh or saltwater, was the
only liquid to be pumped, and sealed with stopa or packing in large
quantities. Other liquids like milk, beer, paints, oil, gasoline, solvents,
tanning acid and medications were made in bottles, jars and barrels and
carried from one place to another. With the capacity to move large
quantities of fluid with motors and small centrifugal pumps, our
forefathers recognized the advantages of expanding production of other
liquids that were not water. And as pumped liquids expanded, the
components of packing materials also expanded to effectively seal these
liquids.
Throughout recorded time and history, the basic design for the stuffing
box and the gland press has not changed, because it has to work to
accommodate, seat, and squeeze the packing. The stuffing box existed
in biblical times, the era of the Vikings, and the centuries of the Spanish
and English explorers, sealing seawater and permitting the progress of
man and history.
Stopa made the transition from sealing the rudder shaft in the bottom
of a sailing vessel, to become braided packing that could resist the
temperatures and pressures or steam and the high velocity shafts.

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