Renowned as Siemens Mobility’s flagship site, the RRX Rail Service Center is expecting around 100 trains to enter the depot every month. This level of throughput puts pressure on the supply chain and requires robust manufacturing solutions that can fulfil the wide-ranging needs of customers quickly and cost effectively. As a result, the company invested in a Stratasys Fortus 450mc Production 3D printer

“We believe our RRX Rail Service Center is the most advanced train maintenance centre in the world,” says Michael Kuczmik, head of additive manufacturing, Siemens Mobility GmbH, Customer Service. “Bringing together a range of innovative digital technologies, we can significantly increase the efficiency of our customer’s rail operations. Stratasys FDM additive manufacturing plays an integral role, enabling us to optimise spare parts for longer life cycles, at reduced cost and in shorter timeframes than ever before.”

According to Kuczmik, the ability to 3D print customised replacement parts on-demand has increased its flexibility to meet customer requirements: “Every train has to go through maintenance several times a year. As you can imagine, all our customers would like this process to be as quick as possible, but they still expect maximum levels of detail, safety and quality. We also have to consider unplanned or last-minute jobs, and if you look at the different train models and companies we service, this requires a lot of bespoke solutions. This is where our Fortus 450mc fits in perfectly, providing us with the ability to rapidly and cost effectively produce one-off, customised production parts.”

Previously, Siemens would rely on traditional methods, such as casting, to meet customer demands. Taking approximately six weeks to manufacture a final customised part using casting resulted in lengthy lead times for customers, and for one-off components this was financially unviable. To make it cost effective, the team would often cast large volumes, which resulted in lots of obsolete parts.

“Using the Fortus 450mc we can 3D print spare parts in a matter of hours; parts that took six weeks, can now be produced in 13 hours,” says Tina Eufinger, business development, additive, manufacturing, Siemens Mobility Division. “Within a week, we can iterate and optimise the design and then 3D print a final, bespoke production-grade part. This has enabled us to reduce the manufacturing time of each component by up to 95%, which has significantly accelerated our ability to respond to customers.”

Beyond replacement parts, the team is using Stratasys 3D printing technology to increase its tooling capabilities. One such example is a ‘connector’ tool that is used to maintain train bogies. Tools for this application are notoriously hard to produce via conventional methods as they have extremely complex shapes and require a high level of customisation. In addition, bogies weigh several tonnes, which means that tough and durable materials are required to withstand significant forces when the vehicle is moving or braking.

Siemens is now using its Fortus 450mc to turnaround one-off tools customised to each bogie in a matter of hours. To meet the demanding material characteristics required, the team is using industrial-grade ULTEM 9085 thermoplastic.

“Well-manufactured connectors are essential tools for the effective and safe maintenance of bogies,” says Kuczmik. “Therefore, finding additive manufacturing materials strong enough to withstand such pressures has been an important exercise. The ULTEM 9085 material is tough, enabling us to leverage all the customisation benefits of 3D printing and replace our traditional manufacturing method for this tooling application.

“The ability to 3D print bespoke tools and spare parts whenever we need them, with no minimum quantity, has transformed our supply chain,” he adds. “We have reduced our dependency on outsourcing tools via suppliers and reduced cost per part, while opening up more revenue streams by being able to service more low-volume jobs cost effectively and efficiently.”