CPC Subgroup
B21D 28/08 Zig-zag sequence working
Full Title
Shaping by press-cutting; Perforating > Punching blanks or articles with or without obtaining scrap (cutting nails or pins from strips or sheet material B21G3/26); Notching > Making more than one part out of the same blank; Scrapless working > Zig-zag sequence working