Industrial Products and Applications - archive issue - year , issue 2, april-may 2021

WALTERs two-in-one globally well-proven concept: eroding and/or grinding on ONE machine

For 17 years, WALTER's "two-in-one" machine concept has been successfully used by the tool manufacturers. What exactly stands behind this WALTER concept, which in the meantime its competitors have tried to copy?

From the manufacturing and technological point of view, the two-in-one concept means that the user can perform 100% tool erosion (PCD) as well as 100% tool grinding (sintered carbide) using one and the same machine. Or, and this is one of its key benefits, both machining methods can be applied for one and the same tool, without losing time re-clamping the tool to a second machine.

This solution becomes particularly necessary and economical for the production of modern PCD tools, in which the PCD material is brazed on the sintered carbide blank. Eroding, grinding, or both in one single clamping, allow unique flexibility in production. The two-in-one machines produced by WALTER can machine any PCD tool used in various industrial sectors, such as wood processing, automotive and aviation industry, or special applications. Since the use of complex and modern PCD tools is constantly increasing, the demand for hybrid machining, i.e. "two-in-one eroding and grinding, is on the rise, as well. This development is already evident in the new PCD tools, which are needed, for example, for machining of composites (CFRP) in the aircraft and aerospace industries. Hybrid machining is the only method ensuring efficient production of such PCD tools.

From business point of view there is another advantage: the fact that the producer can use eroding and grinding operations, or a combination of both machining methods on one single machine, makes his investment in the two-in-one machine a risk-free entry on the PCD tool market, especially for companies which have not been able, or have not intended to manufacture such tools before. In case that the PCD tool business does not develop as expected, the machine can easily be used by 100% for grinding of the existing range of products.

Since the global launch of the "two-in-one" concept at EMO 2001, WALTER has been constantly developing the existing concept and currently comes with three types of machines in this range. Already at that time it was recognized that a powerful grinding spindle is essential for a perfect result, and that many tools can be produced more efficiently by rotary erosion than by wire EDM. In 2006, WALTER introduced a software module multiplying all benefits of the two-in-one concept, enabling also automatic replacement of electrodes and grinding wheels.

In 2016, the "FINE PULSE TECHNOLOGY" was introduced for all "two-in-one machines", which set new standards in terms of surface quality, edge chipping and process reliability in the production of PCD tools. In particular, the generator was recognized as a key element with great influence on the process and therefore was completely redesigned. Improvements in the software and a variety of other influencing factors in the machine design have been also optimized within the "FINE PULSE TECHNOLOGY" initiative. The difference in comparison with other tools available on the market can be seen with naked eyes even in the most common PCD grades with 10μm grain size. A tool manufactured on the two-in-one WALTER machine with FINE PULSE TECHNOLOGY shines on its cutting edge in the same way as a polished (ground) tool. Also, coarse-grained PCD tools, which so far could not be fine finished by using alternative available technologies, can now be fine finished by the new FINE PULSE TECHNOLOGY and a perfect surface quality can be achieved. In some cases, even entire steps in the production chain can now be skipped, because the eroded tools no longer have to be re-sharpened or polished. In 2017, the operating software was expanded by the HELITRONIC TOOL STUDIO software licence "Eroding", making the production of tools, especially the PCD ones, even easier and more comprehensive.