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Special Pumps

suction pipe that may bc needed in
well pumping when the water level
in the well might drop below the
normal inlet.
These pumps that utilize suction
cans in various industry processes
tend not to use the suction bell as it
would take up valuable radial space
in the can. When the process
involves a fairly clean liquid, the
suction screen will not be used.

9.2.2 Vertical pump column
The length of the column
establishes the depth of the pump
and comes in various sections that
are usually standardized to 5 feet
and 10 feet lengths. It is available in
either screwed sections or flanged
connections. The column connects
the bowl assembly to the discharge
head and encloses the line shaft that
is connected to, and drives the
pump shaft. The line shaft sections
arc connected by threaded or sleeve
type couplings.

In clean applications, the shafting is
Figure 9.10: Typical bowl assembly left exposed to the pumpage moving
(Reproduced with permission of Goulds through the column and the bearing
Pumps, ITT Industries) bushings are supported by bearing
retainers, with sleeves protecting the
shaft in the way of the guide
bushings. An enclosing tube can be fitted to isolate the shafting from
the pumpagc and provide a means by which to lubricate the bearings
from an external source with clean water, grease or oil. Stabilizers are
included to support the tube in the column and minimize the
possibility of vibration problems.
The most common materials used in lineshaft bearings on water service
are cutless rubber and bronze. While both of these are widely used in
cold water applications, the cutless rubber is better suited to water
which may include some sand. Carbon beatings are also used in more
corrosive applications and when pumping chemicals with low
lubricating properties.

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