Bending is a stamping process that uses pressure to force the material to produce deformation, forming a certain angle and curved shape. Commonly used bending includes V-shaped bending, Z-shaped bending, and backpressure bending. Bending technology is widely used in metal-producing lines and metal processes for bending sheet metal. There are bending machines, and panel bending machines, roll forming lines, and so on. Sometimes we will also perform the bending process in the die mold.


During the bending process, the force between the upper and lower molds is applied to the material, causing the material to deform. Punch tonnage refers to the bending pressure during bending. The influencing factors for determining the working capacity include bending radius, bending method, mold ratio, elbow length, thickness and strength of bending material, etc.
General bending sequence while designing the pressing mold:
- The short side first, then the long side: Generally speaking, folding the short side first when all four sides are bent. And then, the long side is beneficial to the workpiece’s processing and the bending mold’s assembly.
- Peripheral first and then middle: Normally, it is usually bent from the periphery of the workpiece to the center of the workpiece.
- Partial first, then the whole: If there are structures inside or outside the workpiece that are different from other bending structures. It is generally to bend these structures first and then bend other parts.
- Consider the interference situation and arrange the bending sequence reasonably: the bending sequence is not static. We should adjust the processing sequence appropriately according to the bending shape or obstacles on the workpiece.

The regular production line has a decoiler, straightener, feeder, and then press machine. However, to improve production efficiency and save labor costs, we usually try to shape the metal workpiece in one mold.
According to the production requirements of the end products, we need to design the steps of these processes rationally and choose the appropriate press machine according to the design of the mold. For example, the APA press machine is now widely used in stamping factories. Compared to the bending machine and roll forming line, bending molds will be a more cost-effective solution. Especially when you already have a punch press machine.