Composites rolling assemblies for very high-speed trains, reduces weight by 50%

Talgo has developed a new type of its characteristic running gear frames -rodals- which makes it possible to further reduce the tare weight of the vehicles it manufactures, starting with Avril very high-speed trains.

algo S.A. is a leading company in the design, manufacture and maintenance of high-speed light trains with a manufacturing presence in seven countries such as Spain, Germany, Saudi Arabia and the United States, among others.

By using carbon fibre reinforced polymer composites (CFRP), the rolling assembly mass can be dramatically reduced by 50%, thus improving the energy consumption of the train and passenger capacity.

Current running gear frames are constructed using welded steel plates. Both the geometry of those frames and the welding properties (mainly due to fatigue considerations) do constrain the possibility of weight improvement in the frames with current materials and processes.

New concept

As the running gear is the second heaviest structural component of the train, and the first one in terms of structural resistance requirements, the substitution of steel with new generation composites can result in strong weight reductions with no impact for the rest of operating requirements.

After a careful study of materials and processes, CFRP was considered by Talgo as the best option for the development of a completely new concept in the rail sector.

Up until today, Talgo has successfully finished the full-scale validation of structural requirements according to the current standards (EN 13749), including both static and fatigue tests exceeding 10 million of cycles, with no significant damage after NDT inspection.

The technology used to manufacture the running gear is additionally based on hand lay-up CFRP prepreg, making it fully compliant with the most stringent Fire-Smoke-Toxicity standards in rail transport. Next development steps will see the composite-made rodal running on track, operating under real conditions for final acceptance. In parallel, the development will also be used to gain valuable knowledge to be used sector-wide, in the implementation of a new set of standards regarding the acceptance process of new materials like CFRP in rail transport (CEN/TC 256/SC 2/WG 54).

Modular solution

The new rolling assembly has been developed using the Avril very high-speed platform as a reference, but it could be adapted to other Talgo intercity or commuter vehicles, with positive impacts on capacity of the train, simplified assembly processes, a reduction on energy consumption and of track wear and tear. In addition, all the knowledge created with the experience could be exported for other primary structural components of the train.

This project has been supported by the European Commission through the Shift2Rail initiative.