I'm curious how bolt FOS's are calculated in Solid Works.

My model uses 80% of proof for axial loading (pre-load) which already equates to a maximum FOS of 1.25 (1/.8). Yet when shear and bending moment are taken into consideration, putting the bolt under higher tension, I end up with a higher FOS. ???

Can anyone explain?

Thanks,

Are you interested in FOS for yield or ultimate strength?