Most rail benders I have seen, and one was in Milan in use bending street railway rail, needed the third wheel/form to move so that a radius could be formed. I do not see where the foremost, separate wheel form can move in an arc, or at all, to obtain a radius for a curved rail.
Also, there is the spindle at the front for pulling material into the machine. It does not line up with any of the parts for forming, And, why the wide roller prior to the 3 form wheels? Maybe an answer can be found by contacting the University Library for any further information on the photos.