Goulds Pumps 3180-86 - IOM - Manual (Page 41)

Check Explanation/comment Checked
Check that the eccentric reducer at the suction flange
of the pump has the following properties:
• Sloping side down
• Horizontal side at the top
See the example illustrations.
If suction strainers or suction bells are used, check that
they are at least three times the area of the suction
piping.
Suction strainers help to prevent
clogging.
Mesh holes with a minimum diameter
of 1/16 in. (1.6 mm) are
recommended.
If more than one pump operates from the same liquid
source, check that separate suction-piping lines are used
for each pump.
This recommendation helps you to
achieve a higher pump performance.
If necessary, make sure that the suction piping includes
a drain valve and that it is correctly installed.
—
Liquid source below the pump
Check Explanation/comment Checked
Make sure that the suction piping is free from
air pockets.
This helps to prevent the occurrence of air
and cavitation in the pump inlet.
Check that the suction piping slopes upwards
from the liquid source to the pump inlet.
—
If the pump is not self-priming, check that a
device for priming the pump is installed.
Use a foot valve with a diameter that is at least
equivalent to the diameter of the suction
piping.
Liquid source above the pump
Check Explanation/comment Checked
Check that an isolation valve is installed in the
suction piping at a distance of at least two times
the pipe diameter from the suction inlet.
This permits you to close the line during
pump inspection and maintenance.
Do not use the isolation valve to throttle the
pump. Throttling can cause these problems:
• Loss of priming
• Excessive temperatures
• Damage to the pump
• Voiding the warranty
Make sure that the suction piping is free from
air pockets.
This helps to prevent the occurrence of air
and cavitation in the pump inlet.
Check that the piping is level or slopes
downward from the liquid source.
—
Make sure that no part of the suction piping
extends below the suction flange of the pump.
—
Make sure that the suction piping is adequately
submerged below the surface of the liquid
source.
This prevents air from entering the pump
through a suction vortex.
Installation
Models 3180, 3181, 3185, and 3186 Installation, Operation, and Maintenance Manual 39