If one were to place the 153 individual wires of two of the full locked coil track ropes of the new 3S cable car Grindelwald Grund - Eigergletscher in a row, they would be longer than the Swiss border. In detail this means 2'021 kilometers of high-tensile steel wire with a breaking load of 1'760 to 2'060 N/mm2, stranded together to form a two-layer full locked coil track rope, type INTEGRA with a diameter of 58mm. One of the four track ropes in the INTEGRA-DATA version has 24 optical light wave cables, which have been integrated into the round wire core of the rope in a laser-welded steel tube.
These values may sound spectacular, but for FATZER, custom-made items like these are very common. The challenges for the project mainly concerned the logistics: How is it possible to transport a net tonnage of 132 tons over narrow and winding mountain roads and bridges, which are only rated for a maximum load of 72 tonnes?
Not a new problem for FATZER and the logistics service provider Wipfli Transporte, who have successfully carried out several transports with two coupled trucks in the past. However, in this case, the calculations of an external engineer required a distribution of the net load to 3 trucks, which also had to undergo a special "diet": The weight-reducing conversion measures were also very expensive.
After approximately 3 years of planning and numerous special permits, the 65-meter-long and 212-ton convoy with a total of 1580 hp was first driven from Romanshorn to Zweilütschinen via the Brünig Pass in August. Just under 8 hours were needed for the first 200km of the trip and the remaining 12 kilometers to Grindelwald-Grund took another 3 hours. During the last section, the suspension rope had to be uncoiled and re-coiled a total of six times.
The distribution to three trucks was only possible with a double bobin, which had been specially designed and produced for this transport by the company TRESCO AG and was transported on the second truck in the middle of the convoy.