4.5 Operation
4.5.1 General considerations
Driver may overload if the fluid specific gravity (density) is greater than originally assumed or the rated
flow rate is exceeded.
Always operate the mixer at or near the rated conditions to prevent damage resulting from cavitation or
recirculation.
4.5.2 Operating at reduced capacity
WARNING:
Do not operate mixer below minimum rated flows or with inlet and/or outlet valve closed. These
conditions may create an explosive hazard due to vaporization of fluid and can quickly lead to
mixer failure and physical injury.
Damage occurs from:
1.
Increased Vibration Levels - Affects bearings, seal chamber, and mechanical seal.
2.
Increased Radial Thrusts - Stresses on shaft and bearings.
3.
Heat Build Up - Vaporization causing rotating parts to score or seize.
4.
Cavitation - Damage to internal surfaces of mixer.
WARNING:
If running clearances have enlarged due to wear, seizure may not take place and continued
operation under these conditions may create an explosive hazard due to confined vapor under
high pressure and temperature.
4.5.3 Operating under freezing conditions
Exposure to freezing conditions while mixer is idle could cause liquid to freeze and damage the mixer.
Liquid inside mixer should be drained. Liquid inside cooling coils, if supplied, should also be drained.
4.6 Shutdown
1.
Slowly close outlet valve.
2.
Shut down and lock driver to prevent accidental rotation.
WARNING:
When handling hazardous and/or toxic fluids, proper personal protective equipment should be
worn. If mixer is being drained, precautions must be taken to prevent physical injury. Fluid must
be handled and disposed of in conformance with applicable environmental regulations.
4.7 Final alignment
1.
Run the unit under actual operating conditions for a sufficient length of time to bring the mixer and
driver up to operating temperature.
2.
Shut down unit and lock out driver to prevent accidental rotation.
4.5 Operation
3501 Installation, Operation, and Maintenance Instructions
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