Goulds Pumps CV 3171 - IOM - Manual (Page 24)

24
CV 3171 IOM 05/11
Operating At Reduced Capacity
WARNING
DO NOT operate pump below
minimum rated flows or with
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.
A centrifugal pump should never be operated
continuously near shut-off or zero capacity, or with
the discharge valve closed. To do so may shorten
the life of the pump and greatly increase down time
and maintenance.
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 buildup - Vaporization causing
rotating parts to score or seize.
4. Cavitation - Damage to internal surfaces of
pump.
CAUTION
Serious damage may result if
the pump is run in the wrong
direction.
CAUTION
Operation of the unit without
proper lubrication will cause
bearing failure, and pump
seizure.
Operating At Reduced Head
On motor driven pumps, when discharge head is
dropped below the rated point, the motor should be
watched for overloading. If this condition is likely
to persist, arrangements should be made to either
manually or automatically throttle the discharge
valve to build up head to prevent overloading.
Operating With Surge Conditions
If pump is installed with a quick closing valve in the
discharge line that closes when the 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
Exposure to freezing conditions while pump is idle
could cause liquid to freeze and damage the pump.
Liquid inside pump should be drained.
Final Alignment/Clearance Check
1. Run the unit under actual operating conditions
for a sufficient length of time to bring the pump
and driver up to operating temperature.
2. Check alignment while unit is still hot per
alignment procedure.
3. Reinstall coupling guard.
The coupling guard used in an
ATEX classified environment
must be constructed from a
non-sparking material.