High-tech positioning for technology of the future

ZATC 300 complete with special face plate and integrated cooling concept used for workpiece mounting in a WAAM weld cladding process

As an innovative partner, we like to explore pioneering new paths – so back in 2015, we started to develop solutions with the additive manufacturing sector. ​

In wire arc additive manufacturing (WAAM), an arc of light generates large amounts of heat, creating thermal bridges in the workpiece and face plate. Our material composition and integrated cooling concept safely and reliably discharges this heat, helping to reduce tension in the component. ​

Remscheid, October 2018 – "With Gefertec technology, we're able to reduce our production costs by up to 80 percent for high-volume parts, compared to a powder bed process", says an enthusiastic Matthias Otte, who is responsible for additive manufacturing at Rolf Lenk Werkzeug- und Maschinenbau. Otte is referring to the new 3D Metal Print, or 3DMP, process. Berlin-based company Gefertec, founded in 2015, is currently the world's only provider of this technology. Generative production methods – often referred to as 3D printing – have long been a hot topic in the manufacturing sector and metal component production, and the method is viewed as one of the key technologies in the transition to digital Industry 4.0 production. 

Gefertec's 3DMP is a revolutionary process that opens up a host of new possibilities and boasts a number of advantages over conventional techniques. Unlike the standard powder-based process used to date, the new printing method uses tried-and-tested light arc welding and wire. The melted welding material is applied in layers to build the metal component.

Accurate workpiece positioning is crucial to the success of this process. In all of its five-axis 3DMP machines, Gefertec uses two-axis rotary tilt tables from Peiseler – a global market leader for this technology and numerous other subdevices. Gefertec also offers a three-axis machine in which the welding torches move along x, y and z axes, but most applications require five-axis processing. The Peiseler rotary tilt tables complete the system with two rotary axes, making them one of the core components of the machine. The ZATC 300 is used in the arc 405, the smaller Gefertec machine, while the larger arc 605 is fitted with the ZAS 320. The available space is a key design criterion.

"Generative manufacturing was new territory for us, and it comes with a completely different set of requirements to conventional machining", explains Dr Benedict Korischem, Managing Director at Peiseler. "We committed to the challenge and see enormous potential for our company in our customers' innovative production processes". Generative manufacturing is already being used to produce a wide range of metal components: Gefertec customers span sectors such as tool engineering, ship building and rail transport.

The new 3DMP process boasts some impressive benefits. Compared to conventional processes such as milling, 3DMP can reduce costs by up to 60 percent. Milling processes involve significant chipping and material losses, but wire welding uses the material much more efficiently. Even though the components are milled as part of the finishing process, the amount of waste is significantly reduced. The fewer production stages and lower tool wear also have a positive impact on the bottom line. And the innovative new process can help to cut storage and logistics costs, too. "With our machines, customers can produce components much faster than with a milling process. Because parts can be turned around in a day, users can benefit from just-in-time delivery", explains Marcus Ortloff, Sales Engineer at Gefertec. In particular, significant cost savings can be achieved when machining challenging materials such as stainless steels and titanium. 

3DMP also has a number of advantages over other additive processes, although it is not intended as a direct competitor – every 3D printing technology has its place. The powder bed process, for example, is ideal for very delicate components; 3DMP, on the other hand, can be deployed to produce parts in very high volumes. However, there are some areas of overlap where it is worth comparing the different approaches. "Our process boasts a ten times faster construction rate and significantly better material utilisation", explains Ortloff. With the overspray technique used in powder-based methods, over 60 percent of the material misses the component completely, but 3DMP reduces losses to virtually zero. This has a significant impact on the overall cost of production, particularly when working with expensive materials.

These benefits make the Gefertec technology an attractive prospect for service providers in the additive manufacturing industry. "We're offering players in this market an opportunity to extend their product portfolio, which will enable them to respond even more flexibly to the needs of their customers", emphasises Ortloff. In the future, all service providers will have to offer all additive techniques, because Gefertec's 3DMP technology has now become an industry standard.

The fledgling Berlin-based business claims to have gained a significant head start by developing the process – and it won't be easy for competitors to catch up. The company's technique relies on its expertise in wire arc additive manufacturing, as well as in the development of user-friendly CAM software and in the Gefertec machines themselves. The 3DMP process chain based on these pillars begins with the CAD model that the customer provides to the user of the Gefertec system. The system uses this data to print a workpiece that roughly corresponds to the final shape. A 3D scan of this workpiece is then used to programme the machine, which then proceeds to use light arc welding and wire to build the layers of the component.

The position of the component is critical to the success of the production process, so selecting the right technology partner was an important decision. Gefertec opted to partner with Peiseler and is still working exclusively with the Remscheid-based company. There were a number of reasons behind this choice. "As with all critical components, an exceptionally high standard of quality was a top priority for us", says Martin Lange, a project engineer in Product Development at Gefertec. The strong customer focus and excellent service that Peiseler would bring to the partnership were also important factors. The company's high levels of flexibility and ability to respond to Gefertec's requirements have reportedly been second-to-none. "We make requests and Peiseler makes it happen", adds Lange.

Peiseler satisfied all of the company's technical requirements and played an important role in the development and design process. The resulting custom solutions and modifications are precisely tailored to Gefertec's needs. "The

specially designed ZAS 320 two-axis rotary tilt table in the larger Gefertec machine, the arc 605, is completely unique", confirms Marc Gronau, Gefertec's Sales Account Manager at Peiseler. Aside from the proven components from the ZAS series – such as the worm gear drive, bearings and clamps – the entire table was designed from scratch for this customer.

The company integrated cooling channels between the upper and lower plates of the rotary table; an essential modification for Gefertec's welding application. Although Peiseler offers a range of rotary manifolds for cooling channels and other media, such as hydraulic oil and pneumatics, the system in the ZAS 320 was designed especially for Gefertec as part of a joint development process. Due to the dimensions of the machine, the companies also incorporated a large weighing distance between the trunnion table and counter bearing and used larger-than-average face plates. The tables are fitted with special seals to protect them against welding dust in dry room applications.

Gronau notes that the ZATC 300 two-axis rotary tilt table, which is also based on Peiseler's ATC series and is used to ensure precise positioning in the smaller Gefertec arc 405 machine, was also modified in line with Gefertec's requirements. The standard device was fitted with larger face plates positioned further away from the swivel axis of the stationary trunnion table. The device was also equipped with a cooling system.

"Peiseler's commitment, technical performance and outstanding service and advice have confirmed to us just how important it is to work with well-known component manufacturers", adds Gefertec Sales Engineer Ortloff. His company also chose to partner with Siemens for its control systems and Fronius for its welding technology. With these renowned names on board, the business can rest assured that the risk of process failures is minimised.

Working with eminent partners also involves an element of image transfer. "A brand like Peiseler looks good in our machine and is a great selling point", says Ortloff. The highly rated company is a global market leader that is well-known in the world of mechanical engineering, and Gefertec highlights this fact in its communications, including its technical data sheets and materials for trade fairs, sales pitches and presentations. Reactions from customers have been excellent.

Ortloff believes that 3DMP technology has great prospects in the market generally. His company is planning to double its revenue this year and its long-term vision is for Gefertec machines to become as essential as traditional milling systems, used both as an addition to conventional methods and as a final processing stage in generative manufacturing. These plans harbour great potential for Peiseler, too, as its technology is integrated into each and every machine. "Peiseler is still our number-one choice, and we are looking forward to continuing our partnership".