The Koralmbahn, a 130-kilometre railway line, is a cornerstone of European infrastructure. This high-performance route connects Graz and Klagenfurt with speeds of up to 250 km/h, reducing travel times between Vienna and Klagenfurt to just two hours and forty minutes — a saving of over an hour. As part of this transformative project, the railway line includes 50 kilometres of tunnels, notably the 33 kilometre Koralm Tunnel, over 100 bridges and underpasses, and 23 modern train stations.
At the heart of the Koralm Tunnel are two massive ventilation shafts located in Leibenfeld and Paierdorf—reaching depths of 90 and 110 metres, respectively, and boasting diameters of approximately 8 metres. These shafts play a critical role in the tunnel’s safety and functionality.
To support annual maintenance activities, Tractel designed, manufactured, delivered, and installed two cutting-edge circular maintenance platforms. These platforms feature rack-and-pinion motor systems that ensure smooth vertical movement, enabling efficient and secure access to the entire shaft.
Tractel secured this project through a public tender issued by ÖBB, Austria’s national railway company. The company’s precise technical and commercial proposal, coupled with its extensive expertise in deep motorised platforms, positioned it as the ideal partner for this challenging task.
The project highlighted the strength of Alimak Group’s multi-disciplinary capabilities. Leveraging the collaboration between Alimak Group companies, Tractel delivered a comprehensive solution tailored to the complex demands of this infrastructure. This teamwork underscores the advantages of being part of a global group with specialised expertise across multiple domains.
Adhering to Austrian railway standards was critical to the project’s success. Tractel ensured that the design, installation, and commissioning met stringent local regulations, prioritising operator safety and the functionality of the equipment during maintenance operations.

