Goulds Pumps 3410 - IOM - Manual (Page 35)

STARTING THE PUMP
1. Make sure suction valve and any recirculation or
cooling lines are open.
2. Fully close or partially open discharge valve as
dictated by system conditions.
3. Start Driver.
$
! CAUTION
Immediately observe pressure gauges. If discharge
pressure is not quickly attained - stop driver, reprime
and attempt to restart.
4. Slowly open discharge valve until the desired flow
is obtained.
$
! CAUTION
Observe pump for vibration levels, bearing temperature
and excessive noise. If normal levels are exceeded,
shut down and resolve.
OPERATION
GENERAL CONSIDERATIONS
$
! CAUTION
Always vary capacity with regulating valve in the
discharge line. NEVER throttle flow from the suction
side.
$
! CAUTION
Driver may overload if the pumpage specific gravity
(density) is greater than originally assumed, or the
rated flow rate is exceeded.
$
! CAUTION
Always operate the pump at or near the rated
conditions to prevent damage resulting from cavitation
or recirculation.
OPERATING AT REDUCED
CAPACITY
s
! WARNING
DO NOT operate pump below minimum rated flows or
with suction and/or discharge valve closed. These
conditions may create an explosive hazard due to
vaporization of pumpage and can quickly lead to pump
failure and physical injury.
$
! CAUTION
Damage occurs from:
1. Increased vibration levels - Affects bearings,
stuffing box or seal chamber, and mechanical seal.
2. Increased radial loads - Stresses on shaft and bearings.
3. Heat build up - Vaporization causing rotating parts to
score or seize.
4. Cavitation - Damage to internal surfaces of pump
OPERATING AT REDUCED HEAD
On motor driven pumps, when discharge head or pressure
is allowed to drop considerably below the rated point for
any length of time, the motor should be watched for
heating because the pump capacity increases with reduced
head, as does horsepower consumption. If this condition is
likely to persist, arrangements should be made either to
manually or automatically throttle the discharge valve to
build up head to a safe point.
OPERATING WITH SURGE
CONDITIONS IN LINE
If a pump is installed with a quick closing valve in
discharge line that closes when pump is running, dangerous
pressure surges may be built up that can cause damage to
the pump or line. In services of this kind, some cushioning
arrangement must be provided to protect the pumping
equipment.
OPERATING UNDER FREEZING
CONDITIONS
When exposed to freezing conditions and pump is standing
idle, liquid inside the pump should be drained by removing
drain plugs in bottom of casing and opening vents at top.
3410 IOM 1/2010
33
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