4.6.1.1 Fastening
WARNING:
Risk of serious personal injury or property damage. Fasteners such as bolts and nuts are criti-
cal to the safe and reliable operation of the product. Ensure appropriate use of fasteners during
installation or reassembly of the unit.
•
Use fasteners of the proper size and material only.
•
Replace all corroded fasteners.
•
Ensure that all fasteners are properly tightened and that there are no missing fasteners.
4.6.2 Suction-piping checklist
Performance curve reference
Net positive suction head available (NPSH
A
) must always exceed NPSH required (NPSH
R
) as shown on
the published performance curve of the pump.
Suction-piping checks
Check
Explanation/comment
Checked
Check that the distance between the inlet
flange of the pump and the closest elbow
is at least five pipe diameters.
This minimizes the risk of cavitation in the suction in-
let of the pump due to turbulence.
Check that elbows in general do not have
sharp bends.
—
Check that the suction piping is one or two
sizes larger than the suction inlet of the
pump.
Install an eccentric reducer between the
pump inlet and the suction piping.
The suction piping must never have a smaller diame-
ter than the suction inlet of the pump.
Check that the eccentric reducer at the
suction flange of the pump has the follow-
ing properties:
•
Sloping side down
•
Horizontal side at the top
4.6 Piping checklists
3640 i-FRAME API Type BB2 2-Stage / ISO 13709 2nd Ed. API 11th Ed. Installation, Operation, and Maintenance Man-
ual
33
Summary of Contents for Goulds Pumps i-FRAME 3640
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