A bead is a long, drawn-out impression, which is impressed to increase stiffness in metal sheets or plates. Depending on the workpiece size and material thickness, the ratio of length, width and imprint depth must be adjusted to obtain the maximum strengthening effect. Beads can only withstand the forces acting on it optimally if the correct size ratio is established in relation to the sheet or plate size.
The function of beads and where are they used?
It is also important how the bead runs over the workpiece. There is a basic rule that rectangular workpieces should be equipped with annular beads and vice versa. The stiffening effect is far higher if the shape of the bead run differs from the basic shape of the sheet or plate. Beads must also never cross, as the stiffening effect is lost at the crossing point. The effect of beads has been known of for centuries.
They even stabilised the corslets of knights’ armour. No matter whether to stiffen containers, vehicle bodies or tin cans. They are now used in many areas of industry.
Production by nibbling
At Rime we carry out our production with the help of our punching machine. We have a large selection of different forming tools (dies) with which we can punch beads.
As the beads often exceed the length of our tools, they are produced by means of Punching with resinking. This process is also called nibbling. In the nibbling process the punch is pushed into the metal sheet or plate and the shape of the punch remains in the material as a negative impression. The tool is then moved a small distance forward by the computer control and the punch is pressed into the metal again. This procedure is repeated until the required bead length is reached. In this way, any length and shape of bead run can be produced.