Goulds Pumps 3700 - IOM - Manual (Page 33)

Installation
Liquid source below the pump
Check Explanation/comment Checked
Make sure that the suction piping This helps to prevent the occur-
is free from air pockets. rence 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,
Use a foot valve with a diameter
check that a device for priming the that is at least equivalent to the
pump is installed.
diameter of the suction piping.
Liquid source above the pump
Check Explanation/comment Checked
Check that an isolation valve is This permits you to close the line
installed in the suction piping at a during pump inspection and main-
distance of at least two times the tenance.
pipe diameter from the suction Do not use the isolation valve to
inlet. 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 This helps to prevent the occur-
is free from air pockets. rence 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
This prevents air from entering the
is adequately submerged below pump through a suction vortex.
the surface of the liquid source.
Example: Elbow close to the pump suction inlet
Correct Incorrect
The correct distance between the inlet flange of the
pump and the closest elbow must be at least five
pipe diameters.
Model 3700, API Type OH2 / ISO 13709 1st and 2nd Ed. / API 610 8/9/10/11th Ed. Installation, Operation, and Maintenance 31
Manual