The Lord of the Powder
KSB’s Pegnitz site is home to the additive manufacturing centre, where complex components are produced by a 3D printer. Marco Linhardt is part of the team that works with these pioneering technologies. A site visit.
More than 1,500 people work at KSB’s location in Pegnitz, Upper Franconia. Many of them develop and manufacture pumps and valves. Others deal with materials in the research laboratory or produce castings in the foundry. But Marco Linhardt’s task in additive manufacturing is quite unique. This is because he works in one of the world’s most cutting-edge facilities for so-called powder-bed metal additive manufacturing. Granted: The term sounds unwieldy. But behind it lies some extremely advanced technology.
Upon first sight, the manufacturing centre looks somewhat different: Unlike other production facilities – especially the foundry – it seems more like a laboratory; clean and almost sterile. “Here we work with new manufacturing processes which complement conventional industrial production,” says Linhardt. When talking about his work, the buzzword 3D printing usually comes up pretty quickly. “But we prefer the term additive manufacturing, as it better expresses how the process is applied in industrial production.”
The process – also called selective laser melting – involves a thin layer of metal in powder form being applied to a platform. It is then melted by a laser before further layers are applied successively, which is why experts term the process “additive”. By contrast, classic manufacturing processes such as those using lathes create workpieces by machining blanks, i.e. removing material.
A talent for complex components
Marco Linhardt, who joined the company in 2009, is enthusiastic about his job. The 29-year-old family man started out on a dual work and study programme to qualify as an industrial mechanic and a bachelor of mechanical engineering. After graduating successfully, Marco Linhardt took advantage of professional development opportunities and studied mechanical engineering part-time to gain a master’s degree.
Today he is a development engineer and project developer for additive manufacturing – and part of a core team that has been working together since the end of 2017. It includes specialists from the foundry, the materials laboratory and the production engineering and development departments. The colleagues meet each week to discuss upcoming tasks. “The positive interaction between everyone involved from different departments is what makes our work so special,” Marco Linhardt is proud to say. By now the team has accumulated so much know-how that KSB is able to act as a service provider and consultant to the outside world. “Our unique selling point is that we cover the entire process chain with our holistic experience in design, construction processes, research and development and quality inspections,” explains Linhardt.
In the tea kitchen, the engineer explains the purpose of his work: “Additive manufacturing offers us a whole range of possibilities for improving existing products, for example by redesigning pump components.” Conceivable options might include making components lighter, giving them novel properties or using fewer materials. The groundbreaking process also ensures that parts require less reworking. “New design possibilities allow the production of components that would be virtually impossible to manufacture by conventional means,” the expert says.
An example of this type of complex component is a volute casing with heating channels. It is used in pumps when the fluid handled must be kept at a certain temperature, for example when pumping vegetable oil and caustic soda. Up until now it has not been possible to produce such a component in its complete form – manufacturers had to weld on the channels afterwards. Additive manufacturing means that this part can now be manufactured in a single process.
Another aspect of the specialists’ day-to-day work is manufacturing spare parts for pumps that are no longer produced. This often involves components that are subject to considerable wear. Casting patterns for these older pump sets often are not available anymore, making conventional production prohibitively expensive. With the laser melting process, the parts can be produced quickly and at lower cost. This works as follows: scan the old part, edit it on the computer and print it. The advantage: The system operator does not have to replace a pump completely, but can continue to use the installed pump set. This saves valuable resources.
Quality, efficiency and sustainability
Back to the manufacturing process: Once printing is finished, Marco Linhardt puts on a dust mask and vacuums most of the excess material off the workpieces with a hose, and then hangs the heavy plate with the parts on to a crane to carry out finishing work. In a futuristic-looking machine, the specialist thoroughly removes the last powder residues and collects them for recycling. Following heat treatment he separates the components from the platform with a saw and carries out final processing. Finally, thorough quality checks are performed before the parts are delivered.
“Quality is as important to us as efficiency and sustainability,” he says. For Marco Linhardt and his colleagues, the future has already begun. Because one thing is certain: Additive manufacturing is set to become increasingly important.