Rainer Bürkert, member of the Central Managing Board of the Würth Group (b&m’s parent company), reports on the disruptive potential of this innovative manufacturing process, explaining its strong ecological aspects and its potential to significantly move the industry. The UMFORMTECHNIK MASSIV+LEICHTBAU magazine for forming technology in solid and lightweight construction highlights the process here.

Combining the manufacturing versatility of machining with the advantages of cold forming is a great concept, and eliminating subtractive processes such as turning or milling seems rather obvious, light, and logical: The concrete implementation of this vision, however, required a great deal of development work and head scratching at b&m. A ten-member team from b&m put around eight years of pioneering work into the process, which is called b&m-EccoTec (Ecological Coldforming Technology) and is now to be successively established on the market.

“The target audience for the technology includes manufacturers and suppliers from industries such as automotive, electrical, agricultural machinery, and heating technology,” states Rainer Bürkert. Olaf Ambros, Head of Technology and Development at b&m, adds: “The precision forming process of b&m-EccoTec results in shorter production times and lower costs as part of efficient mass production.”

Variety in the outer geometry

Olaf Ambros mentions a material-related advantage of the process: He explains that cold forming using highly complex rolling tools does not sever the material fibers, but increases the dislocation densities in the crystal structures. “The strain hardening of the part due to forming results in a compacted, particularly smooth surface. With our technology, the energy-intensive heat treatment process step can often be omitted.” This applies especially to the use of AFP steel “which features a combination of high strength and good ductility”.

Ambros also mentions the previously unheard-of possibilities for designing the outer geometry of the cold-formed parts. “Undercuts, serrations, recesses, and grooves are just as feasible as complex profiles and functional surfaces with tight tolerances.”

Decreasing costs per part

He explains that the manufacturing process is not only faster, but also offers extremely short process times as well as a higher output volume of finished parts in one work cycle. In Ober-Ramstadt, b&m is currently already producing formed parts with highest surface quality with tight diameter and runout tolerances in the hundredth range and running gears of class 8 quality. “But there’s more potential here,” Ambros states with confidence.

Subtractive manufacturing

 Thanks to b&m-EccoTec a worm gear shaft can now be manufactured chiplessly, employing only pressing and rolling process steps. Subtractive manufacturing, on the other hand, requires additional gear cutting, heat treatment, and grinding processes. Rainer Bürkert and the Würth Group are so convinced of the market potential of the new technology that a dedicated production facility is currently being built in Ober-Ramstadt which will comfortably house several production lines side by side.

 Rainer Bürkert explains: “To identify its potential, the experts at b&m analyzed and set the processes side by side: For the subtractive machining process, we are looking at around 4 to 6 parts per minute, compared to up to 40 parts per minute with the b&m-EccoTec process.”

Material and CO2 savings

In contrast to the manufacturing of turned parts, b&m-EccoTec enables material and CO2 savings of up to 67%. “Short cycle times, complete utilization of the raw material used, and the principle of strain hardening combined with absolute contour freedom are the crucial advantages,” reports Olaf Ambros.

 In recent years, Baier & Michels has not only conducted numerous tests but has also already produced and brought to market smaller sized b&m-EccoTec formed parts in large series. Olaf Ambros looks optimistically into the future: “We have the right approach. The technology works. The market potential is there.” By the end of the year, a specially developed production line for larger, even more complex parts will go into series production in Ober-Ramstadt.

Focus: b&m-EccoTec

- Combined method of a pressing process and rolling process (known from manufacturing screws from wire)

- Highest precision and surface quality

- Ready-to-install parts without follow-up processes (net shape)

- Combines the design options of subtractive machining and the advantages of cold forming

- No material loss from cutting

- Sustainability thanks to resource and energy efficiency

- Short cycle times

- Potentially no heat treatment required

About

With around 500 employees, Baier & Michels specializes in technical fastener solutions: Cold-formed parts, such as high-performance screws and sealing systems, form the basis. All products and processes come from in-house development and manufacturing in Ober-Ramstadt in Germany. b&m has been part of the Würth Group since 1973.

www.baier-michels.com