Advantages

Very stable operation with little to no shaft deflection.

 

Almost no axial thrust & a reduced NPSHr with impeller inlets on both sides.

 

Increased efficiencies as thrust loads are considerably reduced.

 

Capable of extremely large sizes & flows.

 

Limitations

Generally double suction pumps are considerably more expensive as they are physically larger & heavier in construction.

 

More expensive to overhaul as they require two mechanical seals, glands, wear rings & are complicated to correctly seal the casing joint..

 

They are very sensitive to poor intake designs as uneven inlet flows will unbalance the axial thrust & normal hydraulic stability.