Extensive Tooling Offering Supports Precision Shop’s Success
Zahn GmbH relies on Arno-Werkzeuge for helping the company produce high precision parts using Arno’s customized cutting tools and optimizing its enterprise resource planning system (ERP).
It is mandatory for precision machining shops to ensure reliable processes across its entire range of applications and materials. This can only be achieved by using reliable tool systems, having a team that’s experienced in custom developments and having a well-conceived ERP system that ensures rapid and smooth workflows. Zahn GmbH (Aglasterhausen, Germany) found the perfect partner to ensure all these needs in Arno-Werkzeuge.
Over the years, Zahn GmbH 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, the company constantly works to tight tolerances of 4 microns as well as short-term delivery dates. “We are well positioned to cover a range of materials and applications, and we can react flexibly to customer requirements,” explains Managing Director Lars Pramme.
In two years’ time, Zahn GmbH has switched all of its turning, milling, grooving and drilling processes to Arno-Werkzeuge’s products. For Mr. Pramme, the main reason for deciding to work with only one tool manufacturer was to increase process reliability. “This also made procurement processes much more efficient. But the most important for me was to increase reliability in production.” For example, the company was continuously confronted with inconsistent tools from some manufacturers, which operators noticed because of the amount of wear they experienced with these tools in production.” With Arno, quality is at a constant high level, and the tools are stable in operation.” Mr. Pramme also appreciates the technical expertise and the short communication paths this company offers. “They have people there who can assess the cause when chatter marks occur on a workpiece. In this case, I need immediate support, which I get from Arno.”
Technical challenges are solved on site: Dieter Wollensack, Arno sales manager (left) at a consultancy meeting with Lars Pramme, managing director of Zahn GmbH.
Producing Shorter Chips
Besides more consistent processes, producing shorter chips is another benefit to using tools from Arno. Mr. Pramme explains this by the sample of the AKB short hole drill for high-performance drilling with replaceable inserts. “Normally, drill chips are long. But not with the AKB. Shorter chips prevent chip packing, which must be removed at regular intervals.” The completely coated and polished holder in the AKB system optimizes chip evacuation.
Inserts in four different geometries cover a 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, 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.” Mr. Pramme confirms that it makes a lot of difference when machines continue running reliably until the tool reaches the end of its service life. The entire AKB range of 2, 3, and 5 times diameter with different diameters is used at Zahn GmbH. A range of materials—such as steel, stainless steel, grey cast iron and nonferrous metals—are machined, mainly for hydraulic parts.
Complete Turnkey Solution
Zahn GmbH has also benefited from Arno’s expertise when it comes to customized tools. “We deal with technically competent people who tell you straight off if a tool concept won’t work,” Mr. Pramme says. “They look very closely at the machine and the application before giving their advice.” One of Zahn’s customers recently requested the delivery of a control unit which was urgently needed for drilling stepped holes. “Our Arno contact, Sebastian Seiter, advised us against this solution. After examining the matter in more detail, we found he was right. The resulting tolerance overlaps meant the processes would no longer have been stable,” Mr. Pramme says.
The company needed a reliable substitute and quickly. An alternative was found in only two months, including the tool concept. Mr. Wollensack says, “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.”
ERP Offering and Benefits
Zahn GmbH had 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. The specification also required variable tool compartment
Using company transponders, Zahn GmbH employee accesses items in the Arno StoreManager.
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 Phileas Hauk, who is responsible for tool purchasing at Zahn. “We now have two StoreManagers in operation: one at our shop inUbstadt-Weiher and one here in Aglasterhausen. Our system assumes the control function; not only is the management system in Ubstadt-Weiher linked to ours, but the system also integrates our paternoster storage system and the ERP system here in Aglasterhausen. Everything runs like a dream.”
At Zahn GmbH there is a safety stock level for Arno products, which are constantly needed. This has many benefits, Mr. 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.”
Mr. Pramme says, “It gives us more time to focus on technical matters when we meet our tool manufacturer, and we waste no time handing over purchase orders. And instead of many small invoices, there is only one bulk invoice per month: a very practical solution indeed.”
The right tool is quick to find because of the clear operating layout of the Arno StoreManager.
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 that are also used at the company. With the clear menu structure that is user-modifiable, employees select the required tool on a touchscreen 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 optimize tool requirements for upcoming job orders,” Mr. Hauk says.
The partnership between Zahn GmbH and Arno is a success story that continues. “Arno understands where the real problems lie in the day-to-day production environment and gives support at many levels. Now I have stable processes, full transparency in tool management and so much more peace of mind,” Mr. Pramme says. “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.”
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