process and apparatus for continuously and permanently shaping a plate in plastic material according to an undulated profile . the apparatus includes a guide and positioning surface of the plate ; a moulding and transferral wheel , peripherally shaped according to a plurality of seats , suitable for reproducing a continuous shaped profile ; and a positioning , advancement and maintenance assembly in the form of a plate , peripheral with respect to the moulding wheel , of the mobile type , respectively ; counter - clockwise in synchronization with the moulding and return wheel in a position independent of the moulding wheel . the assembly includes a pre - form presser , upstream of the surface involved in the shaping , set apart by at least one first stabilization and cooling presser , a moulding presser , interposed between the pre - form presser and a cooling presser ; and a possible blade for detaching the plate from the seats .