User guide

Check Explanation/comment Checked
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
expansion of the piping.
Make sure that all piping
components, valves and fittings,
and pump branches are clean
prior to assembly.
—
Make sure that the isolation and
check valves are installed in the
discharge line.
Locate the check valve between the isolation valve and
the pump. This will permit inspection of the check valve.
The isolation valve is required for regulation of flow, and
for inspection and maintenance of the pump. The check
valve prevents pump or seal damage due to reverse flow
through the pump when the driver is turned off.
Use cushioning devices. This protects the pump from surges and water hammer
if quick-closing valves are installed in the system.
Alignment criteria for pump flanges
Type Criteria
Axial The flange gasket thickness is ±0.03 in. (0.8 mm).
Parallel Align the flange to be within 0.001 in./in. to 0.03 in./in. (0.025 mm/mm to 0.8 mm/mm) of
the flange diameter.
Concentric You can easily install the flange bolts by hand.
Suction piping for optional dry pit, outside tank mount, and tailpipe
applications
Checklist
Check Explanation/comment Checked
Install an elbow at the pump. Whenever possible, perform these actions:
• Use long radius elbows.
• Move the elbow further from the suction.
• Eliminate unneeded elbows.
Make sure the suction piping is a larger
diameter than the pump suction.
—
Install separate suction lines when more
than one pump is operating from the same
source of supply.
—
Make sure that the suction piping contains
no air pockets.
—
Make sure that the suction piping slopes
upwards toward the pump.
—
Make sure that all joints are air tight. —
Provide a method to prime the pump. For outside tank mount and dry pit applications,
allow the fluid level inside the tank or pit to rise
above the casing level.
In tailpipe applications, submerge the casing
before you start the pump.
Installation (Continued)
20 Model 3171 Installation, Operation, and Maintenance Manual