Pump Piping - General; Alignment; Starting Pump - Armstrong Design Envelope 4302 Installation & Operating Instructions Manual

installed in such a manner that the pump is not used as a
pipe support.
• Do not rigidly connect the pump to a permanent base (see
fi g. 2.7 on page 10) Note: if the pump must be connected
to a permanent base, the pump must be isolated from the
piping by fl exible connectors and the base isolated from the
building structure on an inertia base.
• Do not install the unit with the shaft horizontal.
• Do not support the installed unit by the motor eye bolts or
by supports to any other part of the pump other than
stated above.
important
All Series 4302 ivs pumps contain a tapped hole in the motor
bracket above the discharge fl ange for draining the well. Pipe
this drain hole to a fl oor drain to avoid overfl ow of the cavity
caused by collecting chilled water condensate or from
seal failure.
2.1. 4 pump piping – gener al
Never connect a pump to piping, always start piping
from pump.
Use as few bends as possible and preferably long
radius elbows.
Do not use fl exible connectors on the suction or discharge.
Make sure piping exerts no strain on pump as this would
distort the casing and cause pump misalignment.
Suction and discharge pipes may be increased at pump
nozzle to suit pump capacity and particular conditions of
installation. Use eccentric reducers on suction connection.
Lay out the suction line with a continual rise towards the
pump without high points, thus eliminating possibility of air
pockets that may prevent the pump from operating.
A strainer of three or four times the area of the suction pipe,
installed in the suction line, will prevent the entrance of
foreign materials into the pump. V" (3mm) diameter perfora-
tions in the strainer are typical.
Test suction line for air leaks before starting; this becomes
essential with long suction line or static lift.
Install, at pump suction, a straight pipe of a length equivalent
to 4 or 6 times its diameter; this becomes essential when
handling liquids above 120°f (49°c). Armstrong suction
guides may be used in place of the straight pipe run and in
line strainer.
Install isolation valve in both suction and discharge lines
on fl ooded suction application; this valve is used mainly to
isolate the pump for inspection or repair.
Design Envelope 4302 ivs and 4382 ivs vertical
in-line pumping unit with integrated controls
Install a non-slam check valve in discharge line between
pump and isolation valve to protect pump from excessive
back pressure and to prevent water running back through the
pump in case of driver failure. Armstrong Flo-Trex valve
may be used in place of check valve and isolation valve on
pump discharge.
caution
important
Do not run the pump for any length of time under very low
fl ow conditions or with the discharge valve closed. To do so
could cause the water in the casing to reach super heated
steam conditions and will cause premature failure and could
cause serious and dramatic damage to the pump and
surrounding area.

2.1.5 alignment

The pumping unit is accurately aligned at the factory prior
to being shipped.
Alignment on the 4302 dualArm may be verifi ed by
assuring an equal gap between coupling halves on both
sides of the coupling.
oper ation

2.1.6 starting pump

The pump must be fully primed on start up. Fill the pump
casing with liquid and rotate the shaft by hand to remove any
air trapped in the impeller. Air trapped in the casing must be
removed by the manual air vent in the seal fl ush line.
Ensure entrained air is removed from series 4302 ivs and
4382 ivs pumps, prior to starting, through the air vent on
the seal fl ush line. Open vent until clear of air.
o per ati n g i n struct i o n s
Discharge valve only must be used to reduce the
pump fl ow, not the suction valve.
Care must be taken in the suction line layout and
installation, as it is usually the major source of
concern in centrifugal pump applications.
in stal l a t io n &
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