METHOD OF COLD FORMING A SELF-ATTACHING FEMALE FASTENER ELEMENT

摘要

A method of cold forming a self-attaching female fastener (20) which include s deforming a fastener blank (120) having an annular pilot, (122) an annular flange (128) surrounding the pilot and a groove (132) in the flange having cylindrical walls and annular protrusions (152, 154) on the flange and pilot , then deforming the protrusions toward each other to form an annular re-entra nt groove (32) having relatively inclined arcuate walls.