Metrom: Hybrid machining in mobile CNC system

The german company METROM will provide a unique attraction at the Formnext trade fair. At booth C41 in Hall 11.0, the exceptional machine builder from Hartmannsdorf near Chemnitz will showcase remarkable technological developments in the field of additive manufacturing. These involve machining centers and mobile CNC machines that can process workpieces predominantly hybrid, i.e., additively and subtractively in the same clamping. The focus of the trade show presentation will be the world’s first mobile repair factory developed jointly with Brandenburg Technical University Cottbus (BTU). Housed in one or two specially adapted 20-foot containers, it enables additive and subtractive machining of components.

At the centerpiece is an exceptional machine from METROM, which can be used in the container and removed from it. This machine utilizes the concept of parallel kinematics and METROM’s innovation of a patented five-axis pentapod design. “Compared to conventional machine tools, we have virtually reversed the machining principle,” explains Marcus Witt, Chief Technology Officer at METROM. “The reason is that we no longer place the workpiece in position for machining on a machine table, but instead, the spindle moves in reverse around the component in such a way that five-axis and highly dynamic manufacturing is possible as a result.” The result is significantly greater flexibility and precision. Thanks to the icosahedron design, the METROM system is also characterized by enormous rigidity, which is 50 times higher than the robot. “With this technology, we have a unique selling point on the market,” Witt emphasizes.

3D printing and milling in the same mobile plant

For processing parts, the METROM machine now uses “Direct Energy Deposition” (DED) with metal in the mobile repair factory. Depending on requirements, a metal wire melted by an arc or laser is applied in layers and thus generates or repairs the metallic component. The subsequent milling work takes place in the same system for its fine modeling. As this takes place in the same setup and thus no further time-consuming calibration is required on a separate system, the user benefits from considerable time and cost savings.

With this hybrid application, which is unique worldwide in a mobile machine, and the BTU Mobile Repair Factory, METROM targets a wide range of industries. In particular, in power plants, chemical plants, the oil and gas industry, shipbuilding, and often distant mining plants and mines, this can be used quickly on site and convinces with its performance. Mainly there, but also in the modification or repair of largescale components, a fast machining time leads to the avoidance of costly downtimes. “Here, our solution offers considerable advantages,” Witt emphasizes. The possibility of manufacturing not only with metal but also with plastic contributes to this, he says. “The fact that this is possible in the same plant also sets us apart from the competition.” In addition, the Pentapod design means that the size of the machining area is not limited. This flexibility also enables maximum efficiency and is outstanding on the market.

Joint presentation with cooperation partners

Visitors to the trade fair can also learn about the technology concept’s advantages at the neighboring booth. Bionic Production is exhibiting the Mobile Smart Factory, also housed in a sea container. Here, too, everything revolves around METROM’s hybrid plant, which in this case, cannot be removed and used separately. At the METROM booth itself, BTU will also provide information on 3D-printed titanium components for the aerospace industry. And Oscar PLT, another cooperation partner, will present laser welding heads for additive manufacturing and repair. In addition, for 3D printing with plastics, partner company 1A Technologies will showcase an extruder with a patented control of bypass nozzles. “In this respect, our guests can expect an exciting portfolio that should convince thanks to its special features,” Witt summarizes.