→ Reliability of unloading and sorting of parts
There are some technical and mechanical constraints when automating the sorting of laser-cut parts:
the sheet can move on the table since it is not held down,
parts moving onto the laser table during the cutting process,
a skeleton that can block when gripping a part,
etc.
The unloading and sorting of laser-cut parts therefore makes more sense for the production of medium-size parts or large batches. Indeed, the production programme can be tried and tested before intensive use.
Johan Elster – Bystronic comments that "evacuation and sorting processes have become more reliable in recent years, opening up the possibility of processing a very wide variety of parts, from single parts to small, medium and large batches."
He adds: “For example, to limit stresses during the unloading process, simply cutting out the skeleton can be very useful.”
Christophe Berquet – Prima-power also insists “on the importance of cutting the skeleton to make it easier to grip the parts.”
Loïc Vicaud – Trumpf adds that “the issues are not the same for thick and thin parts. Automation is more complex for thin parts”.
Serges Bourdier – Salvagnini considers that "to make the process reliable, the raw material must be protected from anything that could cause a collision or burr during the cutting process. Simultaneous charging of the tables with cut parts and new sheets to be produced means that the tables have to pass over each other. However, if the table with freshly cut parts passes over the table with the raw material, there is a high risk of slugs or slags falling onto the sheet to be cut.”
Johan Elster – Bystronic concludes that "the reliability of laser cutting automation is based on a global approach: the structure of the cutting table, the control systems, vacuum or rubber magnet gripping modules, etc.".
According to Loïc Vicaud – Trumpf, “software is also an essential part of automation, in order to secure the positioning of the parts according to the unloading system and to reduce the stress of the skeleton on the parts as much as possible.”
→ Flexibility of the Sorting System and Gripping of Parts
The variety of parts and materials, as well as the launch volumes (small, medium or large batches) are of course essential when determining the requirements in terms of flexibility.
For example, a manufacturer cutting its own parts in medium or large batches won’t have the same requirements as a subcontractor cutting individual parts that are always different. For the latter, the gripping of parts is essential in order to be able to pick up a large variety of parts with the same equipment.
Hugues Cousseau – Bystronic calls for “sorting robots that have several gripping module configurations (vacuum and rubber magnets) that are automatically interchangeable, making it possible to adapt to and sort all types of parts, without an operator intervening.”
Johan Elster – Bystronic also adds that “flexibility is improved when unloading and sorting parts with several arms that can move on both axes at the same time, in an independent and simultaneous manner”.
Loïc Vicaud – Trumpf explains that “flexibility is achieved through, for example, rotating vacuum systems, flexibility in pallet placement, etc.".