Stable processes all along the line – from A for ARNO to Z for Zahn

Article from ARNO-Werkzeuge

Zahn GmbH relies on ARNO-Werkzeuge for the reliable production of high-precision parts, ranging from tool systems and the development of customised tools through to the optimisation of its enterprise resource planning system (ERP).

Zahn GmbH has its head offices in Aglasterhausen, Germany, near Heidelberg. Over the years, the company has gradually specialized in the production of complex high-precision turned and milled parts for major customers in the automotive and aerospace industries. Whether it is a prototype or a series production part, they constantly work to tight tolerances of 4μm, as well as short-term delivery dates. “We are well positioned to cover a wide range of materials and applications and we can react flexibly to customer requirements,” explains Managing Director Lars Pramme. It is mandatory to guarantee high precision to ensure reliable processes across the entire range of applications and materials. This can only be achieved by using reliable tool systems, possessing experience in custom developments, and having a well-conceived ERP system that ensures rapid and smooth workflows. Zahn GmbH found just the partner to ensure all this - ARNO-Werkzeuge (ARNO).

An experienced team (from left to right): Phileas Hauk, responsible for tool purchasing at Zahn GmbH, Dieter Wollensack, ARNO sales manager south, and Lars Pramme, managing director of Zahn GmbH.

A system for stable processes

Over the past 2 years, Zahn GmbH has switched all of its turning, milling, grooving and drilling processes to ARNO-Werkzeuge. For Pramme, the main reason for deciding to work with only one tool manufacturer in these fields was to increase process reliability. “Of course, this also made procurement processes much more efficient. But the most important for me was to increase reliability in production. For example, we were continuously confronted with fluctuating tool batches from some manufacturers. And we only noticed this by the amount of wear we experienced with tools in production. With ARNO, quality is at a constant high level and the tools are stable in operation.” Pramme also appreciates the technical expertise and the short communication paths at ARNO. “They have people there who can assess the cause when chatter marks occur on a workpiece. In this type of case, I need immediate support. And I get it from ARNO.”

The short swarf produced from machining with the AKB drilling system prevents swarf packing and, therefore, machine downtimes.

Long machine running times with short swarf

Besides more stable processes, there are even more benefits to using tools from ARNO. Pramme explains this by the sample of the AKB short hole drill for high-performance drilling with replaceable inserts. “Normally, drill swarf is rather long. But not with the AKB. The swarf is much shorter. This prevents swarf packing which must be removed at regular intervals.” The completely coated and polished holder in the AKB system optimizes swarf evacuation. Inserts in four different geometries cover a wide range of applications. The four cutting edges per insert make the system a viable economic solution, as well as the high feed rates that can be used. Dieter Wollensack, sales manager south at ARNO-Werkzeuge adds: “Stability is also excellent. Even in critical applications, the drill is not affected by untrue running. With AKB, we have a drilling system with the highest process reliability on the market.”

Pramme confirms that it makes a lot of difference “when machines continue running reliably until the tool reaches the end of its service life.” It’s not surprising that the entire AKB range of 2/3/5xD with different diameters is used at Zahn GmbH. A wide range of materials, such as steel, stainless steel, grey cast iron and nonferrous metals, are machined, mainly for hydraulic parts.

Technical challenges are solved on site: Dieter Wollensack, ARNO sales manager (left) at a consultancy meeting with Lars Pramme, managing director of Zahn GmbH.

Complete turnkey solution including tool concept in only two months

Zahn GmbH is not only able to benefit from ARNO expertise when it comes to standard tools. ARNO also offers customized tools. “Here we deal with technically competent people who tell you straight off if a tool concept won’t work. They don’t think in terms of sales or the user. They look very closely at the machine and the application before giving their advice.” For example, a customer recently requested the delivery of a control unit, which was urgently needed for drilling stepped holes. In fact, it was intended only to modify an existing tool. “Our ARNO contact, Sebastian Seiter, advised us against this solution and after examining the matter in greater detail, we found he was right. The resulting tolerance overlaps meant the processes would no longer have been stable,” says Pramme. The company needed a reliable substitute and quickly. That was no problem for the experienced team. An alternative was found within a time of only 2 months, including the tool concept.

Wollensack stresses, “Even if we always try to avoid custom developments, it was the only way in this case to guarantee stable processes. It’s actually our job to supply the customer with the product and the know-how that goes with it. There’s no point my reciting the catalogue. Anyone can look something up by themselves. The real added value is at the swarf and that’s where we have many years of experience which we can harness to assist the customer.”

The right tool is quick to find due to the clear operating layout of the ARNO StoreManager.

Full control and increased productivity with efficient tool management

To ensure that production processes keep running efficiently, tools must fit to the nearest micron and they must also be exactly at the place they are needed. However, small and medium-size companies often fail to have sufficient overview of tool circulation or stock levels mushroom out of control. In the worst-case scenario, this results in machine downtimes due to missing components. Despite regular inventories, bottlenecks in the tool store still occur at Zahn GmbH. “Traceability was not 100 percent guaranteed,” explains Phileas Hauk, who is responsible for tool purchasing at Zahn GmbH, “and I often had to request express deliveries from ARNO. That took a lot of time and was very stressful.” In the end, the decision was made in 2015 to totally revamp tool storage.

Zahn GmbH has strict specifications when it came to the search for the right tool management system. It had to allow the integration of third-party systems and assume the management of the system at Ossfeld, a partner company located 40 kilometres away in Ubstadt-Weiher. The specification also required variable tool compartment occupation and 100% access control. After a detailed market analysis, these demands were only met by one system: the ARNO StoreManager, an automated tool management system with software. “Alone its compatibility with third-party systems makes it unique on the market,” says Hauk. “We now have two StoreManagers in operation, one in Ubstadt-Weiher and one here in Aglasterhausen. Our system assumes the control function: not only is the management system in Ubstadt-Weiher linked to ours, the system also integrates our paternoster storage system and the ERP system here in Aglasterhausen. Everything runs like a dream.”

Using company transponders, Zahn GmbH employees access items in the ARNO StoreManager.

Guaranteed tool availability

At Zahn GmbH there is a safety stock level for ARNO products which are constantly needed. This has many benefits, as Haul explains: “We have everything available immediately and as soon as a minimum quantity is undershot, purchase orders are generated automatically. This reduces the workload enormously.” Pramme adds: “It gives us more time to focus on technical matters when we meet our tool manufacturer and we need waste no time handing over purchase orders. And instead of many small invoices, there is only one bulk invoice a month. A very practical solution indeed.”

Other benefits of the ARNO StoreManager include the space-saving carousel system with variable compartment occupation and rapid data transmission by means of a barcode scanner. Employees simply access the system by transponders which are also used at the company. With the clear menu structure which is user-modifiable, employees select the required tool on a touch screen monitor and then withdraw it from the compartment. “It’s quick and we have full access control. We now know when a tool was withdrawn, by whom, for which job order and for which machine. We have been able to optimise tool requirements for upcoming job orders,” says Hauk with satisfaction.

All in all, the partnership between Zahn GmbH and ARNO-Werkzeuge is a success story that will certainly be continued. “They understand where the real problems lie in the day-to-day production environment and give support at many levels. Now I have stable processes, full transparency in tool management and so much more peace of mind in the company,” says Managing Director Pramme. “It’s an enormous relief to have found a reliable tool manufacturer who provides me with both high-quality products and comprehensive know-how. Open honest consultancy intensifies the feeling of trust within the cooperation and creates an excellent basis for future projects.”