A process in which material is folded back on itself or over a mating part. This is a multistage forming operation. First, a sharp-angle bend is made ; next, the bend is closed using a flat punch and a die. See teardrop hem, rope hem, and open hem.
TheFabricator.com provides metal fabrication professionals with market news, the industry's best articles, product news, and conference information from the Fabricators & Manufacturers Association, Intl.