B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
B21D13/00—Corrugating sheet metal, rods or profiles; Bending sheet metal, rods or profiles into wave form
B21D13/04—Corrugating sheet metal, rods or profiles; Bending sheet metal, rods or profiles into wave form by rolling
B21D13/045—Corrugating sheet metal, rods or profiles; Bending sheet metal, rods or profiles into wave form by rolling the corrugations being parallel to the feeding movement