Installation
Model 710 TruBlue Installation, Operation, and Maintenance Manual
29
Check
Explanation/comment
Checked
Make sure that all the piping joints
and fittings are airtight.
This prevents air from entering the piping system or
leaks that occur during operation.
If the pump handles corrosive
fluids, make sure that the piping
allows you to flush out the liquid
before you remove the pump.
—
If the pump handles liquids at
elevated temperatures, make
sure that the expansion loops and
joints are properly installed.
This helps to prevent misalignment due to linear expan-
sion of the piping.
Example: Installation for expansion
Correct
Incorrect
This illustration shows a correct installation for
expansion:
1.
Expansion loop/joint
This illustration shows an incorrect installation for
expansion:
Suction-piping checklist
Performance curve reference
CAUTION:
Vary the capacity with the regulating valve in the discharge line. Never throttle the flow from
the suction side. This action can result in decreased performance, unexpected heat
generation, and equipment damage.
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 inlet of the pump due to turbulence.
See the Example sections for illustrations.
Check that elbows in general do not
have sharp bends.
See the Example sections for illustrations.
—
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
diameter than the suction inlet of the pump.
See the Example sections for illustrations.
