Especially in railroad tunnels, conductor rails are increasingly used instead of the conventional catenary overhead lines.
This saves considerable infrastructure costs, especially due to the lower overall height and because there is no need to ground components in the overhead line crack area.
Such conductor rails are also used in the Ceneri Base Tunnel (CBT).
The CBT is an approximately 15-kilometer-long double-track railroad tunnel in the Swiss canton of Ticino. It serves as a southern feeder to the Gotthard Base Tunnel in the Swiss Alps, the longest railroad tunnel in the world. The CBT was opened in 2020.
In particular, overhead line specialist Furrer+Frey AG from Bern has made a name for itself with conductor rails for speeds of up to 200 km/h. It planned and delivered the conductor rail overhead line in the CBT and installed Europten.
With the aid of a CVR4.0 high-speed recording system, Furrer+Frey employees, together with specialists from AlpTransit Gotthard Ltd. and the Swiss Federal Railways, were able to observe how the pantograph in the area of the line separator behaves at different speeds:
- Differences depending on the direction of travel, in the knee gait (joint to the front) and in the spit gait (joint to the rear).
- How do arcs occur? Where exactly do they ignite, where and how do they extinguish again?
- How exactly does the aerodynamic behavior of the pantograph play a special role here?
- The focus was also on the associated abrasion and wear on the carbon tailpiece of the pantograph.
The videos were made with a Mikrotron camera at 2,800 frames per second with a horizontal resolution of 2,336 pixels, which provided an excellent basis for evaluation and analysis even at 200 km/h.