SEW-EURODRIVE | Triple peaks

General drive technology

Ansgar Silies

Key Account Manager

Up top the air’s thin – this holds true in both a metaphorical and factual sense. For example atop Germany’s highest mountain, the Zugspitze, the lack of oxygen helps one lose weight. Alpine air slims people down without any physical effort – thanks to the increased basal metabolic rate and a smaller appetite at high altitudes. But first of all one has to reach such heights. Some half million visitors manage this each year, for example with cogwheel train and glacier cable car, and as of 21 December 2017 with cable car! That’s when the new Zugspitze Cable Car commenced operation to Germany’s highest peak additionally and, in doing so, picking up three world records.

Two large-capacity cabins – both with glass floors –transport up to 580 people an hour to the mountain’s summit, providing the visitors a breathtaking mountain and valley view and foresight during the ten-minutes journey.

On their way visitors pass a single steel support pylon for the aerial tramway, the world’s tallest at 127 metres, and also experience the largest height difference of 1,945 metres within one section as well as 3,213 metres of unsupported cable – the longest anywhere. Both world firsts.

Twin cables are used to suspend each cabin of the new Zugspitze cable car. And each of the four cables is 4.6 km long, has a diameter of 72 mm and weighs 153 tons.

To pull the suspension ropes up the mountain, we had to develop a special rope pull system. Logistics up the mountain was a key aspect with this project anyhow.

A total of six years planning and construction have been invested in this shuttle service which gets into gear in the new base station. The cabins are driven via a twin drive having a rated power of 1,800 Nm. The two spur gears were manufactured by SEW‑EURODRIVE, each having a rated torque of 240,000 Nm. Alfred Imhof AG, SEW’s Swiss subsidiary, was responsible for project planning. Project engineer Peter Baumgartner who also selected the three couplings was responsible for the selection of gearboxes.

The twin drive system is structured redundantly so that the cable car can be driven by one drive only, too. Technical safety has an extremly high level in this case.

The couplings are supplied by KTR. They make sure that the power generated by the motors and gearboxes is transmitted to the two cable sheaves. But passengers will hardly notice this due to the breathtaking panoramic views such as the picturesque Eibsee lake, the Alpspitze mountain or the Waxenstein mountain range. The journey won’t be disturbed by coarse judders, more likely it will be a smooth floating ride to lofty thin-aired heights.