Lightweight garage #5 CFRP lightweight train CETROVO from CG Rail GmbH

The vehicle

The use of carbon fiber reinforced plastics (CFRP) has been state of the art in aerospace applications for many years. There are also vehicles in the automotive industry in which CFRP is used. The comparatively expensive material has not yet been used in rail vehicles. However, the increasing desire for energy efficiency is also leading to a rethink in this sector. After all, every ton of vehicle weight saved not only reduces the axle load and wear on the rail tracks, but also leads to energy savings of 0.7 - 22kWh per 100km.

With this in mind, CG Rail GmbH has developed a metro train made almost entirely from CFRP components as part of the CETROVO project. A prototype has already been manufactured and exhibited for the first time at the InnoTrans transport trade fair in 2018.

The technology

The most important new features of the train are the bogie frames, the carriage body, the front cabin and the underfloor cladding, which are all made of CFRP. Several new technologies are used here.

The bogie frames in CFRP differential design consist of two longitudinal and two cross members. Automated preforming using braiding and winding is used as the manufacturing technology. The result is a bogie frame that is 50% lighter and whose service life of over 33 years has been proven in cyclic tests.

A CFRP content of 70% also makes the coach body a lightweight. It is 30% lighter than a comparable aluminum construction. This can be achieved through a further development of the pultrusion process. As a result, large CFRP multi-chamber profiles with wall thicknesses of up to 25 mm and different fiber types and fiber orientations can be manufactured in one piece. There are virtually no limits to the profile length.

The lightweight aspect

This results in a weight saving of 13% for the entire train compared to a conventional metallic construction. Overall, this makes the metro train 15% more energy efficient.

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