SCHUNK Präzisionswerkzeuge GmbH, founded in 1979 by Siegfried Schunk started off in a garage in Coburg, Germany. From its humble beginnings, the former resharpening service has transformed into a solution provider, that manufactures their own precision cutting tools range as well as customised tools for special applications. This former “one-man company” has consistently grown and employs today 15 highly qualified employees.
Christian Schunk, Managing Director, SCHUNK Präzisionswerkzeuge began manufacturing cutting tools in 2010, and continues to grow this segment. The turnover of new tools is now 60% of the business, and supplies the automotive, aerospace, die-mould and medical industries. The company provides regular customer contact and individual service and aims to simplify customer processes by facilitating their tool management. Customers like that they not only buy the tools from Schunk, but also get complete tool management, regrinding, edge preparation and even coating.
Early pioneers of loading mixed tool batches
Schunk invested as early as 1998 in a 5 axis CNC tool and cutter grinder and developed their own chaotic loading system for mixed batches. Founder Siegfried Schunk was implementing a chaotic regrinding system for mixed customer batches, using Manutec Siemens robots on three different grinding machines.
Regrinding with mixed batches of tools has been practiced, at Schunk for more than 20 years, and the employees are used to the flexibility of the chaotic system. For the owners it translates into increased productivity, being able to grind a mixed batch of tools unattended. This ‘industrial’ way of thinking was the main driver for investing in an ANCA MX7 in 2017. For Christian Schunk it was important, to retain the chaotic loading capability and at the same time benefit from the increased accuracy of collet changing. Hence, the company is now investing in a second ANCA MX7 expanding the existing RFID workflow.
Experience with chaotic loading and the development of a digital workflow
To “structure the chaos”, of mixed tool batches and multiple jobs, Christian Schunk has developed his own storage system to sort all tools of a customer order on a common tool board. The board has a label and a barcode containing all relevant job information like tool type, number of tools, due date, and other relevant data, and serves to re-collect the tools after grinding for each customer order. Schunk has not only implemented the ANCA RFID workflow for chaotic resharpening, but also uses the production data in a digital scheduling board showing the status for each job ticket.
Increasing productivity and reducing cost
SCHUNK Präzisionswerkzeuge, has reduced costs and increased operational efficiency by using ANCA’s RFID technology. Its system allows tools to be sorted as required for production rather than by customer orders. Any number and combination of tools from different customers can be prepared for regrinding at a dedicated programming station. Every tool gets assessed at the station, skilled operators then select and modify the required grinding program. The individual program is then coded onto a RFID tool holder and subsequently the tool holder and tool will be placed in a pallet for the grinding machine. Every RFID tool holder receives the customer name and job number, so it is easy to find the original customer order after grinding.
Upon the return of the tools after regrinding, the RFID information gets read out and the tool will be returned to its original customer order. The RFID tool holder goes back into storage and can be used for another job in the future.
In production the RFID information is scanned, and the tool grind file is loaded; all grinding parameters, required wheel pack changes or collet size changes are executed automatically.
Christian explains: “It makes sense to keep collet changes at a minimum, which means tools get usually sorted by diameter and tool type, like square endmills, ballnose endmills or drills. This way we are not only optimizing cycle times, but it also extends the life of collets, and we save the collet adapter. Most importantly, it contributes to a better run out.” He also makes sure the machines are utilized at a maximum; therefore, the employees will start on Thursday to prepare tools for automated regrinding on the unstaffed weekend. The tool pallets are loaded to suit the optimal production processes, using chaotic loading increases productivity and minimizes cycle times.
Chaotic loading is a proven formula for efficiency. Schunk previously worked as per customer order, loading all diameters of one customer together - now they have changed to a fully chaotic loading system, independent from the actual customer order.
For the delivery of their second ANCA MX7, Schunk and ANCA are working on an expanded RFID workflow that will accommodate tool a larger tool diameter of 25mm.
ANCA’s Loadermate and RFID solution work
Andreas Sommer, ANCA Product Manager explains, “ANCA offers a variety of automated regrinding solutions for mixed batches – such as collet loading with Nikken collets, which means that the tool and collet are getting changed together, as per the FX5 with the AR300 robot. The Loadermate allocation sets up a mixed batch of tools for unmanned operation.” Alternatively, ANCA offers collet changing and RFID on the MX platform.
With RFID the required information is recorded at the programming station and the tool is coupled with the RFID tag. The machine picks up the tool together with the RFID tool holder; it then scans the RFID and automatically calls up the grinding program; sets all grinding parameters; and loads the correct wheel pack. If a collet change is required, the machine will execute the collet change automatically. The RFID is parked at an interchange station while the tool gets loaded and reground.
The ANCA RFID solution means customers can chaotically load tools into a loader pallet by creating an individual program for each tool. The tool position inside the pallet can be swapped with another tool anytime if a tool needs to be resharpened in a hurry. The tool and cutter grinder can run the regrinding operation individually and unattended, the duration of unattended machine usage depends on the type of loader and the capacity of pallets.
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