NF E 27620 Standard Dimensions for
Spring washers, waved and curved
Dimensions for d1 and d2 apply to plane (not domed or undulated) spring washers. Surfaces to be smooth and free of rolling defects and bur. Spring washers are supplied raw. Spring characteristics shall not be reduced by surface protections applied. The material for spring washers shall be spring steel, having a C-content of 0,3-0,45%
Dimensional Drawing and Technical Diagrams