The clamping situation in the Heller machining center with the Vero S zero-point clamping system and the R-C2 80 L-130 centric clamp. © Gressel

In practice, the R-C2 gripping and clamping system from the Swiss company Gressel in Aadorf is the key to fully automated 6-sided complete machining. This is because no manual intervention is required from loading the workpiece storage unit with raw parts to removing the fully finished workpieces from the workpiece storage unit. This is made possible by the combined R-C2 gripping and clamping module that can be docked onto the industrial robot, the R-C2 reclamping station or 6-sided station integrated into the process sequence, the R-C2 80L-130 and R-C2L-160 centric clamps and finally the zero-point clamping system to be installed on the machine table, in this case the Vero S with console from Schunk.

Gripper-tensioner combination plus 6-sided reclamping station

Andreas Brunhofer, Product Specialist Automation at Gressel: "The modular-compatible R-C2 gripping and clamping system impresses with its system capability and independence and can therefore be adapted to any suitably powerful industrial robot and any CNC machining center. In the specific application case at the customer Baier, the scope of delivery from Gressel consists of an R-C2 module for the industrial robot, a 6-sided station for reclamping, three R-C2 centric clamps, two further centric clamps and a Vero S complete console. The integration was carried out in cooperation with the system house, so that the customer received a ready-to-use system that he could put into operation in the short term without any major training effort."

By keeping the centric clamps in the system-integrated clamping technology magazine, Baier believes it is very well equipped to cover the workpiece spectrum, which ranges from a few millimetres to around 500 mm edge length, as far as possible. Especially as the R-C2 module, with a dead weight of 3.8 kg, allows a maximum transport weight of 35 kg including clamping device and the workpieces are fixed with a maximum clamping force of 30 kN.

The RCM 6-sided station for automatic reclamping for all-round and complete machining. © Gressel

In addition, the practical layout of the new production system allows for individual manual parts handling during the day, for example, when producing individual critical workpieces, while the parts placed in the workpiece magazine are processed fully automatically during the 2nd and 3rd shifts and at weekends.

The track record: Turn 1 into 3

"Complete 6-sided machining in a single pass thanks to the integration of OP 10 and OP 20 (move the centric clamp laterally into the 6-sided station/clamping station by robot, transfer the workpiece, press on the workpiece and clamp) - this is only available in this form and precision from Gressel and allows us to fully automate production. Unproductive non-productive times due to set-up and clamping device handling are almost completely eliminated, we now produce even faster and obtain even more quality parts per unit of time - that's an important word for us as a machining technology service provider. Especially as we no longer need a large number of clamping devices and the machine operators are significantly relieved in terms of handling clamping devices and workpieces. We are currently using 16 milling machines and machining centers, including three 5-axis machining centers from Heller. Based on our positive experience, we are planning to automate the other two Heller machining centers as well, thereby further strengthening our competitiveness. All in all, the automation on the machining center has turned a 1-shift operation into a 3-shift operation plus x," says Karlheinz Baier, summing up the successful entry into full automation.

Edgar Grundler, freelance journalist