Precision to the power of three
Tool inspection: the maker of tractors, AGCO Fendt, sets extremely high standards in the production of its premium products. Precise tools play an important role here. It is not without treason that Fendt relies on three venturion tool presetting and measuring machines from Zoller to achieve this high standard.
With a company tradition spanning over 80 years, Fendt is one of the major manufacturers of tractors, forage harvesters, combine harvesters and balers. As a premium brand under the umbrella of the AGCO Corporation, Fendt is today present on all important global markets. Last year, some 18,000 tractors and an additional 5,000 gearboxes for AGCO sister brands were manufactured in Marktoberdorf on over 85,000 m² of production area. Core competencies include the development, production and assembly of complete drive units with the stepless vario drives for all performance classes ranging from 70 to 500 HP.
The works in Marktoberdorf, which today offer state-of-the-art line manufacturing with the latest processing centers, focus on the production of gearboxes and the final assembly of the Fendt tractors. The flexible manufacturing system consists of 50 processing centers from StarragHeckert which are loaded automatically. Next to frames and other components, this is where the various shafts for the drives and vario gearboxes are processed. Lean production has always been a leading topic in development.
Jan-Eric Feldmann, manager of the housing and frame production at the Marktoberdorf works, places great emphasis on raising the bar very high: "Fendt tractors are premium products - and all employees live up this quality claim." The manufactured housings include numerous important elements which are later assembled to become the load-bearing structure of the tractors. Add to this the gearbox and rear axle housings.
At a glance: advantages of venturion 800 CNC
- Zoller image processing system pilot
- ergonomic operating elements
- consequent use of brand products
- robust and workshop-compliant
- membrane keyboard for power-operated spindle clamping and
- spindle braking
- flexible adaptation to manufacturing processes
- Autofocus and ROD encoder
- Zoller ace high precision spindle
Roughly 50,000 tonnes of casting iron are processed every year. This results in a production of approximately 250,000 cast iron components per annum, largely on the flexible production line, with most of them having extremely complex geometries.
So it is not without good reason that Feldmann and Werner Schober, foreman in housing production, have placed great emphasis on high precision tool systems in manufacturing for many years. A prerequisite for the use of these tools is exact measurement and tool presetting. Schober looks back: "In 1978 we already acquired the first tool presetting machines for tools from Zoller and operated them successfully." Since 1988 these data have been prepared control-adequate and transmitted directly to the corresponding tool machines. With the purchase of the first measuring and tool presetting machine of the venturion series by Zoller, Fendt took another important step in increasing quality and precision. The second Zoller machine followed in 2009, and the third machine in 2013. Today, manufacturing in Marktoberdorf comprises three venturion 800 CNCs.
The venturions are linked via an SQL server so that any tools, once generated, are available on all three measuring machines. This saves time and costs.
Control-adequate data output
And while on the subject of control-adequate data output. An important aspect is that Zoller offers linking to more than 100 different machine-readable output formats. Hence, manual input is no longer required, as the data are available directly for the corresponding machine controls. A number of different options are available for data output. The measured tool data are printed on a label which is used to identify the measured tool. The data can then be read using a scanner.
Alternatively, the data can be saved on a chip in the tool holder using the Zoller tool ID and read later by the machine control. The safest and easiest data transfer is via DNC network. Here, the tool data can be transmitted directly from the tool presetting and measuring machine to the machine controls.
At Fendt, the worn tools are forwarded directly from the machines to the "tool presetting" department. There they are washed, processed, the drills replaced or fitted with new cutting inserts. The tools are then preset accordingly on the venturiuon 800 CNCs, labeled, and returned to the machine.
New tools must also be loaded, measured and their data saved in the data base prior to being used for the first time. For data saving purposes, each venturion has a hard drive which is updated weekly. As Schober explains, the Zoller measuring machines in the works are not linked to the machining center.
Approximately 200 tools are in the magazine of each machining center. In concrete terms this means that several thousand tools are circulating constantly. The label solution virtually precludes any errors on the machine. "Today, the tools are compared with the stored master data in the machines. Previously it was occasionally possible for numbers to be transposed", says Schober. "Today, we are on the safe side with the venturion." In addition, the labels proved to be the most cost-effective option at Fendt.
At Fendt, two employees work on the venturion 800 CNC per shift. The machines are utilized to capacity and "absolutely reliable" according to Schober. In Marktoberdorf the venturions are equipped with CCD cameras to photograph tools and to compare them with the data stored in the CAD. "We are delighted with the extreme repeatability of the venturion", explains Schober in conclusion. "If we measure one and the same tool on the three venturions, the result is the same on all three machines." And by the way, Fendt has relied on Zoller tool measuring equipment for forty years now. The oldest machine is located in goods issue and performs its duties as reliably as on the first day.