The issue of bending and improving efficiency downstream from the cutting process is high on Salvagnini's agenda. By presenting the B3 ATA press brake the company has sent the market a strong message: Salvagnini is the benchmark for efficient sheet metal bending.

Presented in 2012, the B3 press brake is rewarding all the effort that went into it. In one year, Salvagnini doubled the production to keep up with orders and reorders from increasing customers appreciating the machine for its speed and efficiency as well as its productivity, accuracy and ease of use. Moreover the B3 is the only solution of its kind on the market and is the product of proprietary expertise in panel bending and press brake bending, combining the best of both worlds.

Employing an original solution that teams design innovations with the latest technologies available on the market, this press brake combines the power of a hydraulic press brake with the responsiveness and accuracy of an electric press brake, at the same time maintaining the consumption levels associated with a hybrid system. Part of the credit for this result lies in the operating principle of P4 panel benders: the B3 has harnessed the P4's ability to handle heavy loads highly efficiently, extremely accurately and with impressively high dynamics by drawing on this principle, adjusted and optimised to suit its own purposes.

Two years on, Salvagnini presents the B3 press brake in its ATA version, which employs automatic bending tool set-up to make the bending process even more efficient. ATA (Automatic Tool Adjustment) allows you to change and adjust upper tool length automatically, saving time and, consequently, improving production efficiency when bending both "batch one" and parametric parts. While the operator turns to pick up a new sheet for bending, the ATA system - practically in masked time - automatically sets the tool length and the width of the variable V-shaped groove. ATA uses standard, widely commercially available tools. It can also be disabled so that the press brake can be operated in traditional mode.

ATA (Automatic Tool Adjustment): a different technical solution for kit production on a press brake

When you look at a manual press brake and the effectivity of such a machine, you will realise that no more than 30% of the running time are used for adding value to the part. The remaining time is spent on the tool set-up and management of parts before and after bending. This is a fact.

But there are two ways to improve the press brake efficiency:

Process Automation, that is adding a robot, which handles the process. This has been a "hot" issue for the last 10 years. Nowadays batch sizes are getting smaller or unitary, so it makes more sense to optimise "out of process" rather than "inside the process". The robotic press brake represents an alternative, but typically for larger batches, and heavy, complex parts. Although there has in fact been an evolution over the years in the automation of robotic systems (automatic tool set-up, automatic gripper set-up) the solutions proposed so far are objectively inefficient for kit production with small batches. The other solution is Changeover Automation, which means robotizing the tool set-up.

All tool set-up solutions on the market are mainly focused on the reduction of set-up times. They use robots to remove the set-up and put up a new one, enabling the operator to retrieve new parts and deposit finished parts in stock in the meantime.

Salvagnini offers a different, unique technical solution for efficient and sequential production on press brakes: ATA, "Automatic Tool Adjustment", comes essentially from ALA/ABA (Automatic Length Adjustment or Automatic Blankholder Adjustment), the proprietary tool set-up principle of the Salvagnini P4 Panel Benders: it does not switch the tools but sets the bending length properly. This means it automatically resets the length and always returns the correct length relative to the actual need. This solution makes KIT production, i.e. sequential production possible.

The machine thus performs an automatic changeover thanks to this proprietary device, at a speed that makes it possible to run one item at a time, without loss of efficiency: the changeover of the tool length is fast (between 2 and 10 seconds).

Thanks to the proprietary CNC, which automatically defines and suggests the tool compositions according with required lengths, the operating work is easier; the risk of mistakes is thus eliminated, because there is only one set length.

The MWM option moreover allows the automatic die opening according with the material to be bent, making it possible to sequentially bend parts with different materials, thicknesses or different bending radiuses within the same part.

Salvagnini has recently proven that for example a B3 press brake equipped with ATA and a 3 m die, variable from V6 to V51, can run the same onboard tooling for 10 different parts, ranging from 1 mm stainless steel to 8 mm mild steel. This kind of operation is not possible on a traditional press brake, nor can it be done as efficiently on a press brake with an automatic tool changer kit: while the robot is changing the tools the operator cannot add any value to the part.

A new approach to press brake bending

"Rather than think of ATA as a tool change system, we like to think of it as an actual system in its own right that changes our approach to press brake bending, reinterpreting its use, its potential and its fields of application," explains Nicola Vanzo, Project Management Director at Salvagnini Italia SpA. "Without going into detail, these past 30 years have shown us that panel bending is the best system for bending sheet metal. Whenever press brakes have found themselves competing directly with panel benders, they've inevitably come off second best. Backed by our ongoing development of panel bending technology - which enables us to offer the widest product range in the world and present new solutions like the P2lean - we've advanced the press brake bending field with the B3 ATA by introducing a number of advantages typically associated with panel bending, such as production flexibility, while still retaining the technology's underlying strengths, namely size of investment and versatility. As a result, by adopting the same philosophy as the panel bender, the B3 ATA gives the option of setting up bending tool compositions to suit the part to be made.

The bending tool is configured in real time according to the length of the bend to be made. Normally, the operator would have to be careful to determine and install the various different tooling sets required. Apart from being time-consuming (and unproductive), this also entails using press brakes that are longer than the bend to be made in order to accommodate a number of tooling sets. In point of fact, it's not unusual, faced with the task of producing a part with a number of bends that might be 1.5 m long, for example, to end up having to use a 4m-long press. To make matters worse, the operator has to keep moving from one tooling set to another depending on the bend to be made. And if the parts to be produced happen to be parametric or produced in kits, then you're faced with continually having to reconfigure the machine for each kit and, even if this is done automatically, such technology hardly makes an advantageous option.

With ATA, though, both the role of the operator and the way the press brake is used change and are more akin to the panel bending approach. All the operator is required to do is place the sheet of metal against the back gauge and, where necessary, support it during bending, without worrying about tooling or which tool station to use since the system presents the required tooling set each time. This is the first time that a press brake is being shown as a viable solution for producing a kit made up of parts that require different tooling sets, with a cycle time that is the product of the sum of the cycle times for the individual parts, without having to take into account the time and risk associated with retooling. In fact, it can actually process different kits of different parts in sequence. And this, thanks to ATA, amounts to a real revolution!"

Salvagnini Machinery India Pvt Ltd, Bangalore. Mobile: 099138-15775.
Email: riddhish.jalnapurkar@salvagninigroup.com