[Quacker]

Originally Posted by gaby

The section of the original beam makes it extremely stiff and rigid, hence the crush boxes (if that is what they are).
I believe that the different section of the towbar may make it somewhat more "elastic", avoiding the
need of some other device to absorb energy, although there is another item mounted in figure 36.
The question remains why Volvo opted for a different section and didn't simply weld the tow bar
to the same structure as in the original beam. The more "elastic" property of the round section may
explain that. It is reasonable to assume that Volvo isn't throwing overboard the safety of their cars
when a towbar is fitted, but perhaps this can't be judged from seeing a drawing or a picture.
But not being an engineer, I can't speak with the same confidence as you do.

The round bar is not elastic. By its nature is must be very rigid. However there has been much engineering thought in the design. There are hollows behind where it is welded to the forward beams, approximately where the crush cans were originally, that allow for the welds to stretch and break. However this is very limited indeed compared to the original deformable channel section beam and crush cans. How much so? Again only the original design engineers would know.