KOH Circulation Pump

[jamesframes]

I am evaluating mag drive centrifugal pumps for circulating hot KOH (typically 20-45% at ambient to 195F). Flow is thru a filter/strainer and then an in-line heater. Flow rate to be around 4-6 gpm. Submerged suction.
I have to eliminate PP pump bodies becuase of the high temperature and can't use PVDF becuase of the high Ph. That leaves me with 316SS (or ECTFE which is uncommon).
I believe carbon bushings will be OK - as well as silicon-carbide.
I would appreciate any thoughts or suggestions? Also, is there a good way in this case to provide dry running protection?

 

[TenPenny]

You could consider tefzel lined, which should be good up to 100 deg C (212F) on KOH. Silicon carbide bushings would be the better choice.

For dry running proctection, you might want to monitor motor load.

 

[ash9144]

ECTFE is pretty common for mag drive pumps and would work well in this service. Si carbide bearing/bushing is the better choice.
You will absolutely need to monitor the motor load and shut down the pump before running dry. Dry running a mag drive will destroy the pump.

 

[Artisi]

Check with ITT Gould, when they took over the Allis Chalmers pump company, AC Pumps Cincinnatti had a newly released mag-drive pump which was available in some pretty exotic materials as well as having a dry running version, it might stil be available.