Quality and productivity

Reviewing the developments in the thin sheet materials market and the consequences these will unavoidably have on new generations of press brake machines and their tools, focus is placed to an important degree on the themes of productivity (and therefore the price per bend) and quality (the Tx/Ty concept).

Achieving improved quality and higher productivity during bending is dependent on the combination of machines and tools. Machine builders have made vital contributions by developing the multiple-axis computer-controlled back gauges and mechanical and optical sensors as explained before. By expanding the angle measurement system to multiple points over the entire length of the bend, in principle the crowning system can also be adjusted during the bend cycle by means of computer controls (adaptive bend process). This would appear to be a logical next step towards continued optimization of the press brake process, albeit that both quality and costs will still have to be weighed. In particular in situations involving relatively light bend forces, it appears that electrical press brakes will gain in popularity. The upper beam on these press brakes, for example, is moved by means of a recirculating ball screw or a system of belts. Theoretically, constant (and maximum) pressing force is thereby achieved over the entire length of the machine. Pneumatic power has proven less suitable in actual practice, certainly considering the increasingly-stringent precision requirements. Machine builders are also devoting more and more attention to automation of the press brake process. This could improve the reproducibility of the process and conserve expensive and often scarce manpower.

Automatic tool changing and robot handling of sheet parts combined with automatic storage systems: these are all on their way. This is sure to please sheet metal fabricators whose orders change frequently. Many of the lager machine manufacturers including Amada, Finn-Power, LVD and Trumpf to name a few, have already made significant strides in these areas. Regarding tooling and clamping systems, the future appears to be very bright for Wila’s New Standard. Together with Wila’s Universal Press Brake Concept, the flexibility of the press brake process is enhanced considerably and, in addition, optimum control of Tx and Ty is made possible.

Moreover, the New Standard tools are already fully prepared for the arrival of Automated Tool Changing (ATC). Because the standardization point is further downstream, the engineer’s flexibility also increases greatly. At the same time, it would appear (from the vantage point of flexibility and manufacturing costs) that modular systems will have the future, with reference not only to tools but also to clamping systems. This also offers considerable advantages in terms of repairs and maintenance. In addition, it contributes to significantly extending the economic lifetime of the press brake. Aside from mechanical clamping systems, hydraulic versions are also seen with which all tools can be clamped at once, thus promoting a further decrease in changeover time.

Thanks to the efforts and innovativeness of both machine builders and toolmakers, the press brake process is starting to become a highly developed and high-tech activity within metal processing, as is clearly evident from the above summary.