Roll hemming
Roll hemming is a forming and joining technique .
Forming technology
Roll hemming is the joining of two sheets or materials with tools similar to a hemming machine or by hand. Similar to hemming or flanging , the two materials are connected to one another using a form fit . However, the sheets are not bent too much, but rather rolled into one another using tools. The advantage here is that the surfaces are not damaged and no notch stresses are introduced into the material. The technology originally comes from the plumber, today it is used e.g. B. used to connect sheet metal with PVC film, for example for pulling windows in tin cans, this then comes with friction and clamping.
The process is also used in body construction, in which the automotive add-on parts are connected by means of robot-guided roller tools.
The outer edge of the visible sheet is formed around the corresponding inner part, which is not visible. The entire edge is bent to create a form-fitting connection. To seal the connection, a sealing adhesive is inserted before the hemming process, which later cures through heat and thus additionally supports or holds the position of the inner part to the outer part.