Bearing arrangement for pump load

[TZellers]

I'm looking for pros or cons to arrangement of thrust and radial bearings for pump use. I do have the "Bearings in Centrifugal Pumps" by SKF (1995) which shows the various arrangements, but doesn't go into enough detail IMHO. The classic arrangement I'm used to is having a thrust bearing (double row for instance) on the outer end of the shaft (away from the impeller or load) and the radial bearing (single row for example) closer to the impeller. However, I see for medium duty process pumps they are shown reversed (combined radial/thrust near impeller and radial on the outer end). What's the logic?

 

[plasgears]

The logic is thrust capable bearing at the load and radial on the far side. You need clearance control at the pump end.

 

[brgguy22]

http://www.mrcbearingservices.com

Checkout MRC Pumpac series