摘要 |
A self-piercing rivet includes a substantially cylindrical shank having an outside diameter and a head. The shank has a central blind bore that defines an inside diameter and an annular piercing end spaced from said head. The ratio of the difference between the outside and inside diameters of the shank in the region around the bore to the outside diameter of the shank is in the range 0.47 to 0.52. |