There are many ways to crimp or flare a lip on a cylindrical part. For example, it can be done with a press or an orbital forming machine. However, the problem with those processes, particularly the former, is that they require a good deal of force. For thin-walled parts, or parts made from less ductile materials, that’s not ideal. For these applications, a third method—roller forming—is an emerging option. Like orbital and radial forming, roller forming is a nonimpact process for cold-forming metal. However, instead of forming a head on a post or a rivet, the process forms a curl or lip on the edge or rim of a hollow, cylindrical part. This can be done to secure a part, such as a bearing or a cover plate, inside another part, or it can simply be used to finish the ends of a metal tube to make it safer, improve cosmetics or facilitate insertion of the tube into another part. In orbital and radial forming, the head is formed by a peen attached to a rotating spindle that simultaneously exerts downward force on the workpiece. In roller forming, the peen is replaced with multiple rollers. With the head rotating at 300 to 600 rpm, each pass of the rollers gently pushes and smooths th...