15
Caution! Do not run the pump dry.
The pump may be severely damaged. The pumps use slide
bearings that are lubricated by the pumped product. No lubrication, no bearings. Even short
periods of dry running could damage the pump.
Caution! Do not Dead Head.
Although the radial loads on the bearings are not a concern, the
liquid in the pump will rapidly increase in temperature. This will continue until the boiling point is
reached. Some liquids boil at temperatures sufficient to melt pump components and destroy the
magnets. Other liquids will flash into vapor. This vapor collects at the bushing causing dry
running.
Caution! Mag Drive Mismatch.
Do not
use
inner and outer magnet assemblies with unlike
drives (AK with BK, CK with AK, etc.). Mismatch of drives will prevent coupling from occurring
and
will damage
the pump. Typically, the pump will make a loud buzzing noise with little or no
flow and head developed.
Caution! Cavitation.
Prolonged cavitation may cause pitting on the pump components. Short term
severe cavitation, such as that caused by a closed suction will damage the pump bearings.
Caution! Water Hammer.
Sudden changes in fluid velocity can cause large, rapid pressure
surges. These pressure surges can damage the pump, piping and instrumentation. Typical causes
are rapidly closing valves. Check valves on the suction can also cause water hammer if the liquid
has time to reverse direction before the valve closes.
Recommended!
Power Monitors.
We recommend installing a Sundyne power monitor on all
pumps. These devices are very effective at protecting the pumps from dry running, cavitation or
when frequent overload is expected. They are also very effective for stoppage during tank
unloading applications.
•
Dry
Running
•
Pump
Seizure
•
Closed
Valve
•
Severe
Cavitation
•
Clogged Suction Filter
•
Excess (High) Flow
6-c. SHUTDOWN
If the pump is to be shut down for any reason, use the following procedure:
1. Close the discharge valve slowly to prevent water hammer.
2. Shut off the motor.
3. Close the suction valve.
