Since the implementation of the "Made in China 2025" intelligent manufacturing policy, more and more industries and manufacturing sectors have inevitably moved towards automated robotic production. In the sheet metal bending industry, with the continuous maturation of robotic bending technology, the shortage of skilled bending technicians, and rising labor costs, more and more companies are beginning to utilize automated and robotic bending. This has driven companies to "replace humans with robots, allowing humans to perform more advanced technical tasks," not only improving the stability and timeliness of production but also indirectly promoting the transformation of technical personnel, encouraging them to move towards higher-level technical fields. This has a significant positive impact on enterprises, individuals, and society.
Comparison of robot bending and manual bending
1. Bending stability
Robotic bending, once the technicians have set the appropriate program and ensured the stability of the incoming workpiece dimensions, will allow the robot to continuously produce workpieces with consistent angles and dimensions. Previously, technicians in robotic bending factories will be reassigned to roles involving robot debugging, bending program writing, and calibration. Robotic bending production can achieve a workpiece qualification rate of approximately 96%-100%.
The bending production process can vary depending on the experience and emotional state of the production workers. When workers are in a good mood, have more experience, and are more attentive, the yield rate of the products will be higher and the production speed will be faster. However, if workers are affected by their emotions, lack experience, or are careless, the defect rate of the bent parts will be higher, and they may also have to deal with resignations, delays, and management problems caused by their emotions.
2. Bending timeliness
Robotic bending includes tasks such as destacking, bending following, and stacking after bending. In jobs involving large workpieces, heavy workloads, or requiring 2-3 people to work together, its implementation can save 1-2 people. The benefits are significant. Although robotic bending takes longer than manual production, the overall output per unit time is similar, resulting in substantial cost savings. For small workpiece production, due to the diversity of workpieces, small order quantities, and short changeover times, manual production is faster than robotic bending. However, robotic bending has its unique advantages in small workpiece production: the robotic bending system integrates bending, destacking, and stacking functions, saving manual placement time; the robotic bending system operates continuously and can operate in the dark; from a cost perspective, the timeliness of robotic bending should be consistent with manual bending.
Bottlenecks and countermeasures in robot bending
The main challenges encountered in the production of small parts using robotic bending are switching between bending products and the retraction process after bending larger dimensions. Based on our experience gained through repeated on-site testing, the following values address these two issues:
Bottleneck solutions for switching to bending products:
Standardize tool management by associating product A with tool A and product B with tool B, categorizing them, ensuring a one-to-one correspondence between products and tools, and creating a document database and WGI (Working Geographic Information).
Standardize mold installation. For example, install the bottom mold of product A at the 300mm mark and the bottom mold of product B at the 500mm mark, thus creating standardized documentation.
The hand is specialized, and one hand can correspond to several sets of bending workpieces. All bending workpieces are classified, and corresponding hands are made and documented. Then, when the operator produces the corresponding bending workpiece, the hand can be installed.
Countermeasures for retracting the tool after bending large dimensions:
Sometimes during the production process, some workpieces are bent into larger dimensions than the distance between the cutting tool and the bottom die. For a human, moving the workpiece towards the cutting tool or twisting it can remove it. However, for robotic bending, it is not as flexible as a human hand, and the handling strategy is much more complicated. But we also have corresponding solutions.
The teach-out method involves teaching the robot to gradually avoid the die after bending the workpiece step by step, allowing it to safely exit along a path without interference or collision.
"Adding guide rails is a method used when some products are difficult to remove manually after bending. In such cases, we add guide rails to allow the bent workpiece to exit into a non-interference area, thus ensuring safe tool retraction."
