Night shift in the railway bed of Lyon

Composite-Pilot project: New service - test components produced using 3D printing

For the extension of Line B of the Métro Lyon, the underground of the French city, Röchling Industrial Nancy was commissioned by a leading company for rail infrastructures with the production of Durostone® insulation components. As a new service, Röchling was able for the first time to offer a 3D printed prototype in advance for tests. This part was manufactures by Röchling Direct Manufacturing GmbH in Waldachtal, competence center for the additive manufacturing within the international Röchling Group. During an on-site visit shortly after midnight, the part was mounted on the original rail for an inspection of the design. A test that the customer and the underground operator were very excited about.

Lionel Marquet, Sales Manager Molded Parts from Röchling Industrial Nancy S.A.S., walks in the middle of the track bed of line B of the undergroundin the French city of Lyon. It is 2 am. To his left and right, the rails lead into the depths of the undergroundtunnel. Every day line B transports thousands of people in close intervals - under the river Rhone. Normally it is strictly prohibited to stay here because of absolute danger to life. But yet, the line is closed by the operator and Lionel has a special permit. He is not alone, next to him are two engineers of the subway operator and of the leading company for rail infrastructure - Röchling’s customer. Both supervise the mounting of a 3D printed prototype manufactured by Röchling and check the fit to the rail.

The night shift in the undergroundtunnel was a proposal of the customer and Röchling to the underground operator. “Our fibre reinforced material Durostone® has been used in rail infrastructure for more than 20 years. Based on the specifications, we design and adapt components together with our customer. But we had been looking for a project for a long time where we could offer our customer a new service in form of a 3D printed prototype made of a thermoplastic material to evaluate the design and fitting, before we start the production of compression moulded part made of Durostone®”, Marquet explains.

For good reasons everyone quickly agreed with Lionel Marquet 's idea of a 3D printed prototype. Marquet: “We manufacture high technology components that are directly mounted to the rail. They must have an extraordinarily high degree of accuracy of fit. The entire rail construction must be able to withstand the high loads of daily operation of the underground. A high level of passenger safety and reliability are of utmost importance. With a test run, everyone is more secure.”.

But why is the protype rail support made of a thermoplastic material using 3D printing and not directly made of Durostone® using the compression molding process? “Compression moulding requires an exact tool which shows the negative form of the final part. The manufacturing of a tool for the composites compression molding process is very complex and involves an investment for the customer,” explains Marquet. “While the 3D printing allows to produce a prototype which is exactly showing the geometry and dimensions quicker, easier and cost effective. This enables the evaluation of the design and the accuracy of fit and to carry out adjustments and optimizations before the customer approves the investment in the tool for the compression moulding process."

For the production of the 3D printed test part synergies within the Röchling Group had been used. The test component was manufactured by the competence center for additive manufacturing Röchling Direct Manufacturing GmbH in Waldachtal/Germany. Lionel explains : “With the technological competence of the colleagues in Waldachtal we were able to offer our customer the 3D printed test part following exactly the required design, uncomplicated and in short time”

Back in the underground tunnel an employee of the rail infrastructure company has just finished to mount the 3D printed prototype to the rail. “The mounting was easy. All fasteners fit very well” he says. “The design of the component is very good, it fits perfectly,” he nods to Lionel and the Metró Lyon employee. He takes photos from different directions, enters the result in a test report and closes his portfolio. The test component can be removed now. The night shift is over.

But that is just the beginning of the work at the Röchling site in Nancy. “After the design was approved, we made the tool for the compression molding process and started the production of the Durostone® compression molded parts,” says Marquet. “Everyone involved accessed the test phase as very useful. We will definitely offer this service to our customers as a standard procedure in future projects and looking forward to further cooperation with Röchling Direct Manufacturing in Waldachtal."

With the successful project, Röchling Industrial is further expanding its competence in rail vehicle construction and infrastructure. Composites and thermoplastics from Röchling are used in rail vehicles and rail infrastructure around the world. Depending on the application, they meet the high requirements for fire protection, electrical insulation, weight or mechanical properties, for example. Together with the customer, components are developed that are precisely tailored to the application. On request, Röchling accompanies customers along the entire design and production process - from engineering, through gluing, screwing, painting and assembly of ready-to-install components. With the successful pilot project, 3D printing as a service will also offer customers added value in the future.

More information about our products for railway engineering

More informationi about Röchling Direct Manufacturing GmbH