This blog is translated from German with DeepL.
In the “punching” production process, flat workpieces (mainly sheets up to 8mm thick) are cut to size using a cutting tool (punch). This process is characterized by low lead time at high volumes.
Here are the three main punching processes:
1.1 CNC punching
The workpiece is guided under a computer-controlled tool head, which punches out the contours fully automatically. The tool head can accommodate different punches, which significantly reduces changeover times and makes this process very flexible.
1.2 Total cutting
In total blanking, the workpiece is completely punched out in one tool with one stroke. This allows extremely short machining times and high accuracy of the workpiece. The disadvantage is the high investment costs for the part-specific tools.
1.3 Progressive cutting
As the name suggests, in progressive cutting several tools process the workpiece step by step in sequence. Sheet metal strip, which is drawn from a roll through the tools, is often used as the raw material. The advantages and disadvantages are similar to those of progressive cutting.
1.4 Advantages and disadvantages of punching
1.5 Alternative manufacturing processes
– Laser cutting
– Water jet cutting
– Plasma cutting
1.6 Design tips
When punching, make sure that cutouts within the workpiece are sufficiently far away from other cutouts and from the edge. This distance depends on the sheet thickness. If the distance is less than this, the workpiece may deform unintentionally. It is also important that each punch has a sufficiently large cross-section. This cross-section also depends on the sheet thickness.
Forming is an umbrella term for non-cutting manufacturing processes. The most important of these include forging, deep drawing, sheet bending and tube bending. In this article, only sheet bending will be discussed.
2.1 Bending of sheet metal (press brake)
Sheet metal workpieces are bent with the help of press brakes. The workpiece is pressed into the die by a punch and thus bent. It is possible to bend sheet thicknesses up to 20mm.
2.2 Advantages and disadvantages of bending
2.3 Design tips
Combine as many functions as possible in one sheet metal part.
Bending radius = sheet thickness
A minimum distance to the bending edge must be maintained for holes and cutouts, otherwise they can be “pulled into” the bend.