Goulds Pumps 3180-86 - IOM - Manual (Page 39)

When to install a minimum-flow orifice
You can size and install a minimum-flow orifice in a bypass line in order to prevent bypassing excessive
flows. Consult your ITT representative for assistance in sizing a minimum-flow orifice.
When a minimum-flow orifice is unavailable
Consider an automatic recirculation control valve or solenoid-operated valve if a constant bypass
(minimum-flow orifice) is not possible.
Piping checklists
General piping checklist
Precautions
CAUTION:
• Never draw piping into place by using force at the flanged connections of the pump. This can impose
dangerous strains on the unit and cause misalignment between the pump and driver. Pipe strain
adversely affects the operation of the pump, which results in physical injury and damage to the
equipment.
• 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.
Piping guidelines
Guidelines for piping are given in the Hydraulic Institute Standards available from the Hydraulic Institute
at 9 Sylvan Way, Parsippany, NJ 07054-3802. You must review this document before you install the pump.
Checklist
Check Explanation/comment Checked
Check that all piping is supported
independently of, and lined up
naturally with, the pump flange.
This helps to prevent:
• Strain on the pump
• Misalignment between the pump and the drive unit
• Wear on the pump bearings and the coupling
• Wear on the pump bearings, seal, and shafting
Keep the piping as short as
possible.
This helps to minimize friction losses.
Check that only necessary fittings
are used.
This helps to minimize friction losses.
Do not connect the piping to the
pump until:
• The grout for the baseplate or
sub-base becomes hard.
• The hold-down bolts for the
pump and the driver are
tightened.
—
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.
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Installation
Models 3180, 3181, 3185, and 3186 Installation, Operation, and Maintenance Manual 37