thyssenkrupp Presta AG in Liechtenstein has been producing metal parts using the cold forming process for over 80 years. Many automotive manufacturers simply cannot do without these parts. After all, millions of the small – as well as larger – parts are installed in a great number of steering systems and drivelines. Today, the Cold Forging business unit makes a significant contribution to thyssenkrupp Steering's successful business. One particular specialization has proven to be key to the success enjoyed by the cold forming professionals from Liechtenstein.
Without the components from thyssenkrupp Steering's Cold Forging division, millions of vehicles would not be going anywhere. This is because the cold forged metal parts transmit forces and torques in steering systems and drivelines, among other things. In doing so, they make a major contribution to vehicle safety. Headquartered in Eschen/Liechtenstein, thyssenkrupp Steering can look back on a long tradition in metalworking: it all started in the Principality in 1941 with metal parts manufactured using the cold forming process.
This is a process in which steel is shaped under extremely high compressive forces at room temperature, and thus made to "flow". Special presses are used in what is called cold forging, allowing even complex parts to be produced with high precision at very high speed, but with little material loss. This makes it possible to produce large series of identical parts at comparatively low cost.
Over the decades, the forming professionals have developed into one of the leading companies in their field of technology. Today, the plants in Liechtenstein, Poland, Mexico, and China process around 260 metric tons of steel every day, producing 1.1 million parts. Most important customer: The sister business unit "Steering Column". "Our colleagues produce more than 20 million steering columns every year. And for the inner steering shaft, where the power is transmitted, they need a high number of cold-formed parts, which we produce for them," explains Pierino Casagrande, CEO of the Cold Forging operating unit. Customers in other divisions, too, rely on the components from the business for which Casagrande is responsible. The specialist for bulk metal forming supplies automotive manufacturers such as VW or BMW and tier 1 automotive suppliers such as GKN with precision parts for sideshafts and transmission components. The business unit also produces large quantities for brakes and car seats as well. The company is also involved in the non-automotive business, however: customers such as Husqvarna and Stihl, for example, rely on axles and shafts, crankshafts and pinions from thyssenkrupp Steering for their chainsaw engines.
But what makes the cold forming specialists at thyssenkrupp Steering so successful? Pierino Casagrande has a clear answer: "We have a decisive unique selling proposition: we manufacture many parts without subsequent machining, and focus to a large extent on ready-to-assemble parts. Everything is manufactured in one step in this process. This means: we achieve the required parts geometries in just one step – or one press run – and without mechanical post-processing. Other suppliers often have to incorporate additional mechanical processes, such as grinding or turning. This gives us a decisive cost advantage over our competitors."
Extremely powerful presses are used to achieve the desired forming in various steps. "It takes a very high pressure to leave a lasting impression in a steel part," explains Thomas Keppler-Ott. "We're talking about at least 800 N/mm2, or 80 kg per mm2," says the head of Innovation/Technology.
This is made possible by special high-precision presses with a press force of up to 2,000 metric tons. But the pure force with which the forming experts work is only one part of the story, as Pierino Casagrande points out. "Above all, it takes ingenuity and excellent people to produce perfect, ready-to-install components – and innovations to further develop our processes." The declared goal at all times is to form in an intelligent way, so the right setting of the machines cannot be achieved simply at the push of a button. "It takes highly skilled colleagues with a great deal of experience."
And such people are also needed to make the right tools. This happens at the Oberegg site in Switzerland: "That's where we have highly specialized people, using the latest technologies, who are able to build the perfect tools." Thomas Keppler-Ott adds, "We work with complicated technologies every day, where little things make all the difference. After all, we are working in the micrometer range here. That's why both our people as well as a high level of experience are absolutely crucial."
This is especially true in the sister business unit's steering column business: "With our technology, we can produce ready-to-install, one-piece components cost-effectively, whereas other competitors weld their parts together – and for the safety components in steering systems, that's a highly critical process and one that is also expensive," Casagrande reveals.
"No matter how good the surface finish and how high the strength: at the end of the day, cost is the deciding factor," says Keppler-Ott. Therefore, they always make the production costs a core aspect of their work in the Cold Forging business unit. The engineer cites an impressive example to explain how important even the smallest further developments are: "If some small trick enables us to save just 1 cent per part in the production of 30 million parts, then that means a total saving of 300,000 euros! That's why we do everything – and I really mean everything – to avoid having to resort to mechanical finishing."
And, time and time again, they actually manage to shift the boundaries of cold forming just that little bit further. For Keppler-Ott and his colleagues, this precise issue is not just a part of their job, but has become their passion: "We are totally motivated to keep developing our technologies – all the time and up to the point that we hone them to absolute perfection."
Given the increasingly demanding challenges, the forming specialists will continue having the opportunity to pursue their passion in the future. "We've got the right answers to the megatrends of electric mobility and sustainability, for example, with innovative solutions," says Casagrande. "Electric mobility, for example, requires larger parts and high-strength materials to transmit the significantly higher forces. Up to a certain scale, none of this poses a problem. But, of course, we are also pushing ourselves to the limit here. We've got to continue innovating, developing good tooling concepts, and equally good production processes, so we can press as much as possible with as little force as possible."
Sustainability and thus the carbon footprint are also major topics, and increasingly part of the specifications prescribed by discerning customers. By 2035, most automotive manufacturers will expect the entire value chain of all components from their suppliers to be completely carbon-neutral. This means that not only our own electricity and gas consumption must be sustainable, but also the entire logistics and all purchased parts and materials as well. This is an incredibly tough challenge, as there is still no carbon-neutral steel available anywhere in the world.
"In this respect, we definitely have a very big advantage with our specialization in cold forming processes, because we make do with significantly less material and lower energy inputs compared to other processes," explains Keppler-Ott. "We generate significantly less waste than, say, hot forging. The use of materials is one fundamentally vital point – and another is for us to have significantly less reworking in the end." In addition, thyssenkrupp Steering is increasingly purchasing materials with a high recycled content. Within the next years, thyssenkrupp Steering will have made the energy needed for its production operations completely carbon-neutral – just like the entire Automotive segment of the corporate group to which it belongs.
Autonomous driving and innovative solutions such as steer-by-wire will also leave their mark on thyssenkrupp's cold forming specialists. After all, fewer steering columns will be needed in the future. So, they have long been working on new business areas at the headquarters in Liechtenstein. Casagrande: "We are always on the lookout for new business segments. We take a very close look at where there is potential, and in what areas we can score points with our processes. In our work with our customers, new opportunities and applications continue to emerge where our technology could be an advantage." Casagrande is convinced: "Our scope of processing is far from exhausted. There are always new challenges and opportunities to use our technologies." And to develop them further to perfection with the utmost passion.