The workpieces can be pushed into the measuring area of the coordinate measuring machine completely clamped. © Klaus Vollrath

"The transfer line has a total of 27 pallets as well as numerous set-up, buffer and inspection stations," reveals industrial engineer Serge Truttmann, co-partner and operations manager of the plant in Altdorf. Due to the usually very long processing times on the individual machines, the workpieces can generally be moved along the transfer line in both directions without any time delay, whereby they remain on the pallet in the same clamping position. This also applies to measuring in the coordinate measuring machine.

In the case of critical accuracy requirements, a component can therefore be measured again between roughing and finishing. This makes it possible, for example, to compensate for minor position tolerance deviations when boring holes. To ensure the highest possible precision, great importance is also attached to temperature consistency. The entire hall is kept at a constant temperature of ± 1 °C with the help of large air conditioning units. In the separately enclosed measuring room, the temperature is even kept constant at ± 0.5 °C. Further measures include maintaining sufficient time intervals to ensure that the temperature of the workpieces is equalized and documenting the workpiece temperature during the measuring process using thermocouples.

"As we machine both individual items and medium-sized batches, the TopSolid Cam CAD-CAM system is used throughout all machining processes," says Martin Meenen. On the basis of the CAD

Based on the customer's data, all machining steps are planned end-to-end, the clamping positions are defined and the required clamping devices are designed. Once the optimum machining strategy has been determined, the required tools are determined and assigned to the relevant jobs. The tool management system integrated into the CAD program manages a tool pool with several 1,000 different tools, including many special designs such as spindle tools up to approx. 1,500 mm in diameter. All tools are equipped with RFID chips from Balluff. Preparation and testing are carried out in parallel to setting up the workpieces on pallets. They are then fed into the magazines of the relevant machining center.

Synergies by complementing the locations

"After taking over the largely run-down company, we were fortunately able to rehire around 25 employees from the original workforce," reports Serge Truttmann. Many of them are highly qualified and have many years of experience in operating the sophisticated machines and systems. This also applies to the associated peripherals, including the CAD-CAM software.

"The merger will result in considerable synergies for our two sites in Emmerich and here in Altdorf," says Lucia Esposito. At the Emmerich site, there are numerous machines, some with very special features, such as a system with an installation space length of up to 12,500 mm and some highly dynamic machining centers with high cutting performance. On the other hand, however, these do not quite achieve the accuracy values that can be guaranteed in Altdorf. The measuring room of the coordinate measuring machine in Emmerich is also smaller than the one in Altdorf. It therefore makes sense to rough down large structural components in Emmerich from 32 to 7 tons, for example, and then have them cut to final dimensions in Switzerland. Conversely, there is the possibility in Emmerich of assembling components machined in Altdorf into welded constructions and thus extending the value chain. The company is now considering carrying out additional processing steps at the Swiss plant, such as shrinking bushings.