What happens to a nuclear power plant when it is no longer needed? Whereas other buildings are simply demolished, scrapped and disposed of, dismantling a nuclear power plant is much more complex: some of the huge metal components are contaminated with radiation and must be dismantled using specially developed equipment.
When an energy supplier decommissioned a nuclear power plant, Weisser Bärwinkel was one of the first points of contact. The company, based in Maulburg (Lörrach district), develops machines that dismantle steel structures, cut equipment and even filter contaminated water. “We break down large nuclear power plants into small pieces,” summarises director Michael Kern. Weisser Bärwinkel covers a wide depth of production, including laser cutting, welding, milling and assembly. Seven lathes and milling machines are available for mechanical machining operations, along with a 25-strong production team working in shifts, as well as designers and engineers.
Thread tapping in demanding materials
The systems built at Weisser Bärwinkel sometimes extend over several building levels and consist of high-grade steel components. From raw water tanks and pipes to high-pressure pumps, Weisser Bärwinkel handles the manufacturing of every component itself. All components that come into contact with liquids are made of 1.4571 high-grade steel and connected via countless precisely cut threads. High-grade steel is a challenging material for thread machining, especially in qualities such as 1.4571 or 1.4404. “The chips are tough, break poorly and can get stuck, especially in blind holes,” explains Michael Kern. This was precisely the central challenge in thread production. For a long time, Weisser Bärwinkel used a competitor’s tool for thread cutting. However, recurring problems arose with certain components, especially in tough high-grade steel. Sales representative Oliver Mattes from Gühring recalls: “The threads have always been a big issue. It was simply a process that repeatedly caused difficulties, especially in INOX. Since we started using Pionex, the customer has had no more worries.”
All-rounder with a focus on INOX
The Pionex is a tap for a wide material range, optimised for high-grade steels. Its geometry reduces torque and improves chip removal – a decisive advantage with tough INOX materials. For Weisser Bärwinkel, this means fewer tool breakages, more stable processes and shorter cycle times. The drill is available in versions for blind holes and through-holes. This allows both narrow, closed internal contours and long threaded holes to be manufactured reliably.
“With the Pionex, the threads run reliably and we can work precisely,” explains Michael Kern. “Process reliability has increased significantly.” In addition to high-grade steel, Weisser Bärwinkel also performs machining operations on materials such as grey cast iron, mild steel and cast aluminium. “The customer performs machining on many different materials,” explains Mattes. “With the universal Pionex, we can cover all of them.” The tool is a powerful all-rounder and suitable for a wide material range – an advantage for operations that need to manufacture flexibly.
„This is economically interesting because I use tools for as long as they are costeffective and can even recycle them afterwards.”
High-level optimisation
Weisser Bärwinkel has been using the Pionex for over ten years now. But although the tool works reliably, Gühring has not stopped product development. Six months ago, the Pionex received a facelift. All variants were then converted in the company. The further development is particularly evident in improved cutting edge geometry, optimised chip spaces and a tool with a high level of performance. These factors are particularly effective in INOX materials, where conventional tools quickly reach their limits. “It is an advantage of Gühring that they continue to develop at a high level,” says Michael Kern. “The new facelift offers me even greater process reliability. I can perform more machining operations and the tool works even faster.”
A collaboration that pays off
In addition to the tool itself, Michael Kern is particularly impressed by the excellent service provided by Gühring. “The service at Gühring is simply superb,” praises M. Kern. “You can call them, the Gühring Online Shop is good, and it contains cutting data that you can use without hesitation. And if we have any questions, we get answers very quickly.” The company also uses Gühring’s complete tool cycle: drills and milling cutters are sent in a service box for refurbishment. Tools that can no longer be reground are collected in two yellow barrels in the manufacturing department and then sent to the Gühring recycling facilities – 150 kilograms of carbide per year. The company closes the loop completely with Tool Management and receives an additional 15 % bonus on the carbide market price. “This is economically interesting because I use tools for as long as they are cost-effective and can then even recycle them,” explains Michael Kern.
Tool Performance Report
| Tool | Pionex | Competitor |
| Article number | # 8330, #8354 | – |
| Material | X6CrNiMoTi17-12-2 (1.4571) | X6CrNiMoTi17-12-2 (1.4571) |
| Diameter (Ø) | M2 – M20 | M2 – M20 |
| Cutting speed (vc) | 10 m/min | 6 m/min |
| Thread depth (ap) | 2xD | 2xD |
| Tool life | 450 threads | 350 threads |
28 % longer tool life with 40 % faster machining
