Abstract: A machine for forming corrugated plate from a flat sheet defined by a plurality of serially arranged corrugating stands. At least one stand has cooperating corrugating rolls defined by a plurality of disc shaped dies which, during corrugating, are rotated at differing rates so that the peripheral speed at a selected diameter, of each such disc substantially equals the linear speed of the plate being corrugated. The discs can be constructed of disc shaped die halves, the axial position of which can be varied so as to vary the corrugation pitch or the profile while maintaining the pitch constant. Drives for the corrugating rolls and, in particular, for the disc dies can power rotate all dies or only some of them while others are free wheeling.