Pump Operation Precautions; Shut Down The Pump; Vibration - Bell and Gossett e-80SC Series Instruction Manual

5.4 Pump operation precautions

General considerations
CAUTION:
• Vary the capacity with the regulating valve in the discharge line. Never throttle the flow
from the suction side since this can result in decreased performance, unexpected heat
generation, and equipment damage.
• Do not overload the driver. Driver overload can result in unexpected heat generation
and equipment damage. The driver can overload in these circumstances:
• Make sure to operate the pump at or near the rated conditions. Failure to do so can
result in pump damage from cavitation or recirculation.
Operation at reduced capacity
WARNING:
Never operate any pumping system with a blocked suction and discharge. Operation,
even for a brief period under these conditions, can cause confined pumped fluid to
overheat, which results in a violent explosion. You must take all necessary measures to
avoid this condition.
CAUTION:
Avoid excessive vibration levels. Excessive vibration levels can damage the bearings,
stuffing box or seal chamber, and the mechanical seal, which can result in decreased
performance.
NOTICE:
• Avoid increased radial load. Failure to do so can cause stress on the shaft and
bearings.
• Avoid heat build-up. Failure to do so can cause rotating parts to score or seize.
• Avoid cavitation. Failure to do so can cause damage to the internal surfaces of the
pump.
Operation under freezing conditions
NOTICE:
Do not expose an idle pump to freezing conditions. Drain all liquid that is inside the pump
and the flush lines. Failure to do so can cause liquid to freeze and damage the pump.

5.5 Shut down the pump

1. Slowly close the discharge valve.
2. Shut down and lock the driver to prevent accidental rotation.

5.6 Vibration

After startup, vibration can be measured on the pump bracket at the base of the
horizontal (H), vertical (V), and axial (A) directions. The maximum expected value is 0.15
in/sec (3.8 mm/sec) RMS (ANSI/HI 9.6.4) when operating in the Preferred Operating
Range (POR) flows from 70% to 120% of the best efficiency point (BEP) (ANSI/HI 9.6.3).
Operation outside the POR, but within the Allowable Operating Range (AOR) from
minimum flow to 85% of the end of the curve increases the vibration value by 30%. If the
vibration recorded exceeds these values, shut down the pump, diagnose and fix the
problem, re-start, and re-check the vibration.
Series e-80SC INSTRUCTION MANUAL
– The specific gravity of the pumped fluid is greater than expected.
– The pumped fluid exceeds the rated flow rate.
5 Commissioning, Startup, Operation, and Shutdown
17