Fastening element

A process for forming a fastening element, comprising the steps of:

• providing a cylindrical steel stock;
• cutting a cylindrical piece of steel having a predetermined length from said steel stock;
• bending said cylindrical piece of steel to form a U-shaped body having a first bar-shaped member extending longitudinally along an axial direction, and second and third bar-shaped members extending in parallel to each other along a direction normal to the axial direction of said first bar-shaped member;
• positioning said U-shaped body in a main die such that said second and third bar-shaped members are oriented vertically downward of said first bar-shaped member, wherein said second and third bar shaped members extend through respective holes defined in said main die and respective ends of said second and third bar-shaped members contact an auxiliary die disposed below said main die, such that said first bar-shaped member is disposed a predetermined distance above an upper surface of said main die thereby leaving a gap between said first bar-shaped member and said upper surface of said main die;
• pressing said first bar-shaped member forcibly downward with an upper pressing die, thereby flattening said first bar-shaped member while folding and forcing respective sides thereof outwardly along the axial direction of said first bar-shaped member to form first and second ribs extending outwardly beyond respective connecting positions between said first bar-shaped member and said second and third bar-shaped members;
• and,
• after pressing commences but before said upper pressing die has completed pressing said first bar-shaped member, lowering said auxiliary die thereby allowing said second and third bar-shaped members to yield while the first bar-shaped member is being pressed.