More flexibility in the production toothed wheels
Zahnradwerk Pritzwalk is increasing its flexibility in the manufacture of complex toothed wheels thanks to gearMILL and a DMU 125 monoBLOCK from DMG MORI
For over 45 years Zahnradwerk Pritzwalk GmbH has stood for both technical competence and high product quality as well as for a customer and solution-orientated work principle. With around 300 qualified experts the company from Brandenburg manufactures toothed wheels, shafts and couplings for a multitude of different customers worldwide from sectors such as rail transport, wind power and mechanical engineering. In order to make the production of the many different and diverse toothed wheels even more flexible, the plant installed a DMU 125 monoBLOCK from DMG MORI together with the DMG MORI gear machining software gearMILL in the year 2014.
The growing call for single parts and small series means that we depend on flexibility in production”, explains Bernd Kontak, Technical Director at Zahnradwerk Pritzwalk. “We also have to respond more quickly today in order to remain competitive.” Procuring the right tools for the gear cutting machines takes time and is expensive, especially where products vary. “This is only viable for large series.” While searching for a manufacturing solution that would work with conventional standard tools and still fulfil the high demands on quality – the plant is ISO 9001:2008 certified - Zahnradwerk Pritzwalk came across DMG MORI.
With DMG MORI gearMILL DECKEL MAHO Pfronten created a gear machining software that has never stopped undergoing further development. Combined with a standard machine from the manufacturer the software enables the complete machining of many different types of toothed gears. Jörg Röhl, from Production Planning at Zahnradwerk Pritzwalk, describes how the DMG MORI gearMILL software works: “First we define the type of toothing and record the data preset in the drawing. The software can calculate the subsequent cutting paths from this and generate the NC program via a post-processor.” Different milling tools are used depending on the size of the spaces in order to achieve optimum machining volumes. “The benefit lies in the fact that we only need standard tools, from roughing right through to finishing.”
Zahnradwerk Pritzwalk uses DMG MORI gearMILL in combination with a DMU 125 monoBLOCK. The gear experts can machine both soft and hard parts with this machine. Bernd Kontak prizes the versatile solution: “Because the software is able to mill very many different and complex types of toothed wheels, we can machine a very wide range of products – from module 4 to module 50 – on a single machine.” They can even produce herringbone gears without the space normally needed in gear cutting machines. DMG MORI also integrated protuberance toothing, where the tooth foot is milled separately, in the manufacturing solution during the ordering process. Another special feature is the specially produced milling table. A recess in its centre provides ample space for holding shafts, which of course boosts the machining spectrum even more.
High quality thanks to complete machining
Zahnradwerk Pritzwalk also profits from compete machining on a single machine where quality is concerned. Bernd Kontak tells us: “The complete production can be carried out if necessary without any retooling operations, which of course can lead to inaccuracies and at the end of the day the milling quality is often so good that grinding processes on another machine are no longer necessary.” This saves time and means a level of efficiency can be achieved that is similar to that of gear cutting machines, especially in the case of small lot sizes. "Delivery times of four to six weeks are realistic”, adds the Technical Director. This ensures shorter down times, in particular for repair and service job orders.
MG MORI gearMILL fits perfectly into day-to-day production at Zahnradwerk Pritzwalk. Vertical integration ranges from construction to machining and on through to heat treatment and gains additional flexibility thanks to the gear machining software, even during the offer preparation phase, as Jörg Röhl knows: “DMG MORI gearMILL simulates the production of the toothed wheel on the PC and calculates the tool paths on which the runtimes in turn depend.” In addition potential collisions can be prevented in advance.
The use of modern manufacturing technologies and the continuous search for alternatives in order to remain competitive reflect the innovative orientation of the corporate philosophy at Zahnradwerks Pritzwalk. The company also places great importance on the qualification of its employees. A ten-day course was held when the DMG MORI gearMILL was introduced, for example, to train the employees in the handling of the new software. Bernd Kontak goes on to add: “Training next generation employees as well as offering internal and external courses for further education are measures that promote employee motivation and strengthen our technical competence for the future as well.”