Sorry for the cryptic message.
As you write, BB means between bearing.
With double shaft deflection I mean a fisical double bending due to the weight and the radial forces acting on the shaft.
Shaft deflection shall be limited in each pump type to not have eccesive vibrations and/or internal wear due to contacts.
But in more than one occasion I have found the reccomendation that double shaft deflection can not be acceptable in any case. I can understand this suggestion is reasonable...
I'm searching some article, book or simple suggestion helping me for a good selection between a reciprocating and a screw compressor when operating conditions are in the application range of both of them.
