First 3D printed safety-relevant part approved in the railway sector

Mobility goes Additive (MGA), a network dedicated to exploring the adoption of AM in the mobility sector and pushing industrialization, has announced the approval of the first additively manufactured, safety-relevant component for the railway industry. The part in question, a brake suspension link for a metro brake unit, is already in use at Hamburger Hochbahn AG, the transportation system operator in Hamburg, Germany.

MGA was formed in 2016 and has, over the years, brought on members from across the additive and mobility sectors. Today, the network has over 100 members. The Approval working group within Mobility goes Additive was formed in 2017 with the express goal of obtaining first-time approval for a 3D printed, safety-relevant component. Today, that goal has been achieved.

The 3D printed component was approved through a joint collaboration, which brought together different qualification concepts. A series of quality assurance steps, extensive testing and detailed documentation were carried out, in a process which was ultimately assessed and approved by TÜV SÜD Rail GmbH.

Once operational approval for the 3D printed brake suspension link was completed by the Hamburg Technical Supervisory Authority (in accordance with BOStrab, the German regulations on the construction and operation of light rail transit systems), Hamburger Hochbahn AG commissioned the 3D printed system. This was in August 2019. Today, the part is in place, running smoothly on a Hamburg metro line.

The 3D printed part’s approval marks a significant first in the transport sector, where additive manufacturing is being increasingly explored for the production of spare parts. Up until now, we’ve mainly seen non-operational components, like passenger hooks and headrests, undergo the AM treatment, so the approval of the safety-relevant component is a big step ahead. In fact, the approval process is expected to lead to the establishment of a standard for future approvals in the railway sector.

The Approval working group within MGA is headed by Siemens Mobility GmbH and includes Deutsche Bahn AG, Fraunhofer IAPT and IGCV, Hamburger Hochbahn AG, Knorr-Bremse System für Schienenfahrzeuge GmbH, Photon AG, SBB Cargo AG and TÜV SÜD Product Service GmbH.