With the increasing demand for highly flexible automatic processing, there is a growing need for an easy and time-saving bending process.
The CNC sheet bending machine features a unique two-way bending mechanism that keeps the sheet material horizontal during the bending process, avoiding space flip. It includes functional components like a positioning device, automatic die change, and operator, making it possible to achieve fast, highly flexible, and automatic processing.
Compared to the press brake processing method, the CNC panel bender (as shown in Figure 1) doesn’t require a die change, has a short working stroke, a fast feed rate, higher overall efficiency, and facilitates flexible production.
Figure 1 CNC panel bending machine
The successful development and promotion of products has brought to light the challenge of meeting the diverse process needs of various workpieces. This challenge is now a key issue in the development of bending machine technology.
Thanks to its free bending characteristics, the bending machine offers a lot of flexibility in the development of the process. It does not require mold changes or adjustments. By combining the upper and lower bending die with the compression die, a variety of bending processes can be achieved, resulting in superior process performance.
In this article, we will explore the features of panel bender process realization using typical workpieces from various industries.
Flattening process
The flattening process, also referred to as edge hemming, is a common technique used in sheet metal bending. It enhances the strength of the sheet metal edge while simultaneously making it smooth without the need for polishing.
To achieve the flattening of a press brake machine, two bending processes are required. Firstly, a 30° acute punch with an inserted deep V-slot is utilized to bend 30° to 45°. Then, the flattening die is employed to press the material.
On the other hand, when the panel bender machine executes the flattening process, there is no need to alter the mold. The bending beam and the pressing beam collaborate to produce a variety of flattening effects, including the bottom flattening process of hemming.
For both forward and reverse flattening on the panel bender machine, there is no need to flip the sheet. Instead, it is laid flat on the table surface and bent at an angle of 30° to 45° using the conventional bending process. The formed bending corner is then transferred to the lower die table and flattened using the pressing die. The entire process takes only a few seconds, as shown in Figure 2.
If bending is required after flattening (Fig. 3), the panel bending machine can handle the task directly.
Fig. 2 Bottoming and flattening process
Figure 3 Bending process after flattening
The switchgear and elevator industries sometimes require a specific type of flattening called “opening flattening” (as shown in Figure 4) to improve the strength and feel of the door edge.
To achieve this, panel benders can work in combination with a bending beam and a compression beam to easily create a variety of bending sizes and angles in the first pass, and then quickly achieve the desired final flattening effect.
Figure 4 Flattening process with openings
Rounding process
The rounding process (as shown in Figure 5) is now a necessary step for most manufacturers when producing their workpieces. To achieve this process, specific molds are required. However, different angles and radii of the arc need different molds, which can be expensive and time-consuming to produce.
In contrast, a bending machine only requires an additional bending process to achieve the rounding effect. With its efficient and continuous automatic bending capability, the arc can be formed by combining multiple small-angle bends. This method not only produces perfect results, but also doesn’t interrupt the continuous processing of the workpiece.
Figure 5 Panel bender for arc bending
Using the conventional bending method, even if more segments are used, there will eventually be creases on the outside of the arc formed by continuous bending. This is due to the processing mechanism of the panel bender, which cannot meet the process requirements of some industry workpieces.
As a senior sheet metal equipment supplier with many years of research and development experience, we have continuously tested and finally developed a new set of arc process realization scheme. Through the mutual cooperation of the folding die and ram processing and forming, the crease now appears on the inner side of the arc, ensuring that it does not affect the surface smoothness.
This has improved the forming efficiency, and we can provide a suitable arc process scheme according to different sizes of arc and accuracy requirements, saving time and improving efficiency while meeting process requirements.
The advantage of the panel bender processing technique is not only to save time and money, but also to process workpieces that conventional bending machines cannot handle. For example, the side mounting plate shown in Figure 6 requires only two processes on one side – a 90 ° forming and a 1/4 arc forming.
If processed with a bending machine, first folding the 90 ° forming would prevent the arc from being processed, and folding the 1/4 arc forming first and then processing the 90 ° straight edge would certainly affect the already processed arc surface. However, this can be easily achieved with a panel bending machine, efficiently and with high precision.
Figure 6 Side mounting plate
Shaped bending process
Shaped bending is a broad term that refers to the process of achieving various smaller size shapes by utilizing a panel bending machine’s free bending path and die combination.
For instance, U-shaped bending with an opening of less than 6mm, small Z-shaped bending with a 1mm step difference, N-shaped bending of various small sizes, and so on. Refer to Figure 7 for examples.
Figure 7 Common shaped bending parts
Although these formed shapes can eventually be processed by the press brake machine, they can be processed in one go using the panel bender.
The entire process does not require changing the mold or turning the surface, especially for larger workpieces. This results in low labor requirements and higher and more consistent machining accuracy.
Conclusion
Panel benders have garnered considerable attention owing to their high processing efficiency, robust mold function, and flexibility in production. With the increasing promotion of panel benders, they are expected to come in contact with more industries, customers, and varied process requirements.
As a leader in the sheet metal forming industry, we are committed to investing more effort in the development of the process to cater to our customers’ needs.
