Pump recommendation for a custom transformer oil cooling system

[Rokkit43]

I need a pump recommendation for a custom transformer oil cooling system that is relatively smaller than a typical industrial transformer or locomotive tk. It is a 900 gallon rectangular tank requiring only 40 GPM at 75 FT, SG = 0.95, Viscosity = 34 @ 40˚C (mm2/s), Fluid = Synthetic Ester dielectric oil. The pump should mount on top of the tank lid. Current pump is a Polypro Vertical Mag Drive Centrifugal. We experience electrical arcing inside the pump due to high fluid velocity. I would prefer to switch to a PD pump (gear or vane) but I am having problems finding one that is not too large and heavy for this application, (current Renner pump is 1.5” flanged and weighs only 65#). The Viking Model AK493 meets the required flow but is a big heavy 3” pump, for example. See attached for more information.

 

[TugboatEng]

Is your pump available with a conductive plastic construction? If conductive plastic components are available for your current pump that would provide a bolt in solution.

Edit: I see your pump is available in stainless steel. That would also solve the problems.

 

[Rokkit43]

Unfortunately I am told that this pump is not available in either stainless or a conductive plastic. Per Renner Engineering "Renner does not prefer to change the materials of construction to conductive non-metallic or a metallic material as it will affect the efficacy of the magnetic coupling through the separating can and likely require a larger motor. It is also an area of which they have no experience and much design and testing would be required". I agree this would be the ideal solution. Thank you for responding.

 

[EdStainless]

Do you want to stay seal-less?

http://www.chempump.com/Curves/series/nc-series/nc_60cycle_1750/html/nc1750-a05.html

There are hundreds of options out there. the problem is narrowing it down.


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P.E. Metallurgy, consulting work welcomed

 

[TugboatEng]

I'm curious about the original specification of a plastic pump for a non-conductive fluid. This is highly unorthodox. If your requirements were clear and this is the pump that was specified I would have some serious questions for the manufacturer.