Thanks to the advance of network expansion and the changeover from copper to optical fibre, many of the heavyweight conductors are no longer in use. This means that so much space can be freed up in Swisscom exchanges that they can be dismantled and consolidated. However, the giant copper conductors are not only found in the exchanges. They also run through the underground network of cable routes and shafts – where there is a shortage of space, particularly in the cities! To enable the new optical fibre cables to be drawn through and to prevent any further cable routes having to be built, cablex is pulling the old copper conductors – some of which are up to 50 years old – out of the concrete underground pipes.
Use of a special vehicle makes it possible to draw out the heavy cables. The reel on the lorry can pull up to eight tonnes. If this is not sufficient, the copper conductor can be attached to the lifting arm. This can pull 18 tonnes. However, considerable caution is required: The cable routes are also home to cables that are in operation and must not be damaged. That is why the technicians in the shafts have to take care that nothing else is torn out when the copper cable is extracted. For this reason, continuous communication via radio is enormously important. The five-strong team managed to remove 120 tonnes of cable from the cable routes in five nights. This enabled the existing infrastructure to be used for the new optical fibre cables and construction measures were not required.