15/12/2009

Key to reduced emissions: Schuler supplies modern production line for new ZF high-performance gearbox

Transmissions play a key role in the development of vehicles with lower fuel consumption, reduced emissions and alternative drive systems. This was the general consensus of experts attending the VDI Transmission Congress in summer 2009, organized by the Association of German Engineers (VDI). What this means in practice is illustrated, for example, by German transmission specialists ZF, whose newly developed eight-speed automatic gearbox has been available in the BMW 760i since fall 2009. The new gearbox significantly reduces fuel consumption and can be flexibly adapted to varying drive concepts – especially hybrid drives. ZF aims to have produced around 200,000 of this new transmission generation at its Saarbrücken facility by the end of 2010. The facility itself is designed to manufacture one million transmissions per year. Key gearbox components are sourced from ZF’s facility in Schweinfurt. The forming specialists of the Schuler Group recently installed a new production line here, on which ZF manufactures various parts for its new high-performance gearbox. Production was launched on the line in October 2009.

The completely automated line consists of a hydraulic blanking press supplied by Schuler with a blanking force of 315 metric tons, as well as a mechanical knuckle-joint press from Gräbener Pressensysteme, a subsidiary of the Schuler Group. The latter boasts a press force of 1,200 metric tons. It also includes a coil line supplied by Schuler Automation for maximum coil widths of 650 millimeters and maximum coil thicknesses of six millimeters, as well as an integrated 3D transfer system. The two presses are linked by a shuttle system. Tools are changed with the aid of a corresponding cart at two set-up facilities.

“The new press line is a real first. We have entered a new performance dimension with the technology used by ZF. With a cycle rate of 30 strokes per minute, we can reach top output levels,” explains Armin Schuetz, a project engineer at Gräbener Pressensysteme.

Part quality and output as key requirements

The performance of the machines was a key factor for ZF in awarding the contract to the Schuler Group. “Part quality and output levels were the decisive factors in the bidding process,” explains Heinz Henz, project manager at ZF. He adds: “The new press line also had to fit perfectly into our manufacturing environment and offer long-term flexibility.” ZF’s bid specification included the production of enclosure plates, connecting plates, disk drivers, cover plates and various clutch parts. Important for all parts is their near-net-shape production. A key advantage for Schuler was the fact that its machines had already proved their reliability in everyday production at numerous ZF facilities.

During the bidding phase, Schuler’s engineers were already able to present a compelling concept, whose development involved contributions from companies throughout the Schuler Group: in addition to Gräbener Pressensysteme as the general contractor, the project involved Schuler Hydrap, Schuler Automation in Hessdorf and Schuler’s manufacturing facility in Erfurt.