Goulds Pumps 3796 i-FRAME - IOM - Manual (Page 32)

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.
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.
1
2
1. Enough distance to prevent cavitation
2. Eccentric reducer with a level top
Installation (Continued)
30 Model 3796 i-FRAME Installation, Operation, and Maintenance Manual