Tens of thousands of people ski in the Alps every day during the ski season. To avoid long queues at cable cars, you need a fail-safe technology. The cableway world market leader Doppelmayr / Garaventa therefore relies on long-lasting and low-maintenance geared motors for station operation Nord Drive Systems.
From Ischgl in Tyrol, Austria climbs a so-called Dreiseilumlaufbahn with two fixed suspension ropes and a circulating Zugseil the Pardatschgrat. It overcomes 1251 altitude in less than 10 min. Of course, the top speed of 7,5 m / s is way too fast for the station area. Here, the cabins are disconnected from the cable and gently braked by tire conveyor. At the boarding platform, they only move at walking pace.
The rollers on the cab suspension are in the station on rails. Friction modules make after decoupling of the pull rope with the tire conveyor contact and provide the power transmission. Multi-axis segments are per V-belt Gear Motor driven. The builder of the railway is Doppelmayr, a company of the Doppelmayr / Garaventa group, the leading manufacturer of cable cars with 14.800-completed ropeway projects in 91 countries. The company has been working with Nord Drivesystems since 2005.
Drives for all plant types
Johannes Moritzhuber from Doppelmayr's detachable ropeway systems department explains: "At NORD, we can rely on the drives to fit all plant types. We have had good experiences with the company for a long time. Necessary equipment options are implemented flexibly, the drives are very reliable, quiet, and Nord ensures a fast spare parts supply worldwide. "
Overnight in the garage
In Tyrol and in the neighboring Vorarlberg, where the Doppelmayr, in cooperation with the drive specialist, realized a monocable gondola on the Grasjoch, the cabins will be garaged after the end of the operation. Over a steep ramp, the cabins are driven into the multi-track garage below the valley station. The weight continues on rails, which span both the station and the garage. There is a smooth transfer of the cabins from the tire conveyor to a conveyor chain. Even more space saving is the transport in the garage of the Pardatschgratbahn by vertical conveyor, which is moved by a lifting drive. The horizontal transport, even when driving on the vertical conveyor, is done throughout with tire conveyors.
Unification as a principle
Many years ago, the cable car specialist had largely modularized its product lines. As before, each cable car is individually configured for geographic, geological and climatic conditions at the installation site. However, the modularization allows cost-effective project planning and production as well as standardized planning and quality assurance.
For drives for the station area, the manufacturer has completely switched over to IE3 motors. This also applies to the garage, where the drives do not work in continuous operation. The increased energy efficiency class IE3 has only recently become mandatory in Europe. However, Doppelmayr benefited from the reduction in variants and the special advantages of Nord's IE3 engines, namely higher thermal and overload capacities, as well as their suitability for 50Hz and 60Hz networks worldwide.
Special equipment no problem
The main requirements are a long product life and reliable operation at ambient temperatures from -30 ° to + 50 ° C. Moritzhuber reports: "Nord has the necessary understanding of the conditions of use and has pointed out, for example, that we would get more temperature tolerance with a lubricant other than the standard for the 5 ° C gearboxes. This is absolutely relevant in our alpine projects and helps to realize a long-lasting, low-maintenance drive solution. "
Nord offers equipment options for a very wide temperature range and has implemented standstill heaters, rust-proof brakes and damp proof insulation for drives at Doppelmayr. The drives on the tire conveyors operate at low speeds and have been equipped with forced ventilation: they are stronger than self-ventilating fans and can be switched on as needed, thus offering an energy-saving option. In addition, the fans have been converted from 2 poles to 4 poles. As a result, the noise emissions in the passenger area could be significantly reduced.
Other equipment options reduce, among other things, the installation and maintenance costs. The drives are delivered ready for connection with integrated power and signal plugs. In addition to the general simplification of maintenance, this resulted in great savings during commissioning. An air gap monitoring of the brakes has also been implemented by the drive manufacturer. A micro-switch signals the wear of the brake discs, thus ensuring the always reliable function of the brakes and allows timely readjustment or replacement.