„Ultra-precise manufacture“

Liebers: Ultra-precise manufacture of special chain links

Christoph Liebers GmbH und Co. KG was the very first company to use the Bihler Leantool progressive tooling system. The system was used to implement a tool for manufacturing chain links on a new GRM-NC stamping and forming machine. With this combination, the toolmaker is able to open up new production capacity for its customers but is also consciously placing itself at the forefront of new tool development.

By manufacturing tools on the basis of the Bihler Leantool progressive tooling system and a new GRM-NC machine, Gaimersheim-based Christoph Liebers GmbH und Co. KG is pursuing two strategic goals. “This allows us to create manufacturing capacity for our customers and puts us as a toolmaker in the position to develop, manufacture and test tools for them in a highly efficient and extremely flexible way,” explains Managing Director Michael Starke. “At the same time, we wish to quite deliberately place ourselves at the forefront of this development, as we see very considerable potential for the future in this area.” And the company believes that what the future holds is primarily smaller runs and an increasing number of variants, which simply cannot be realized with the complicated, long-term design and development processes that have been used to date.

Starke: “Standardization in toolmaking is the key to a rapid, agile response to market requirements. The Bihler Leantool progressive tooling system makes it possible to meet these requirements perfectly, without immediately running up against any system limits in terms of complexity. And the Bihler technology on the GRM-NC offers many degrees of freedom for implementing pretty well any manufacturing concept. The knowledge and experience that we gather in the process are things that we will then be able to make available to our tool customers.”

Precise component variance

In concrete terms, the components made with the tool that has been manufactured using the Bihler Leantool progressive tooling system are special chain links for steel and stainless steel conveyor chains. These links have attachments such as lugs and grippers and are positioned between ordinary links. The customer is the Munich-based precision chain manufacturer iwis, and the GRM-NC machine now allows them to cover their wide range of variants perfectly. What was so impressive was the universal suitability of the machine and ist high level of flexibility, which makes it perfect for the highly efficient and ultra-precise manufacture of the 50 or so different component types. And precision is of the utmost importance here. After all, even the smallest discrepancy in a link soon adds up to a chain that is too long or too short. Another benefit is the extremely short time it takes to set up a new tool, which can be less than half an hour. And last but not least, it is an intelligent tool that does not have to be changed every time the component variant changes.

Ideal project implementation

The whole project kicked off in early 2018, starting with a precise analysis of the range of component variants – and the realization that it would be easier to implement this variety optimally using the linear manufacturing concept rather than with the radial concept originally envisaged. At this time, development of the Bihler Leantool progressive tooling system was so advanced that it was available for this first joint pilot project. Once Liebers’ customer had decided to go with this solution, the project was officially started. After four months developing and building the tool, it was tested for a week before the first finished, precisely dimensioned parts could be produced. In November, Christoph Liebers GmbH und Co. KG will take delivery of the new GRM-NC and production is scheduled to start immediately. After all, the tool that has up to now been thoroughly tested on an identical machine can be used directly with no adaptations. This will mean that the entire project will have been completed to the full satisfaction of all those involved. Michael Starke sums up: “Together, we have succeeded in breaking new ground. It was an exciting experience and an absolute success, thanks to the very close and reliable collaboration with Otto Bihler Maschinenfabrik.