Coupled to the Future

837,000,000,000 ton-kilometers. Germany’s Federal Transport Infrastructure Plan forecasts this gigantic transport volume – some 25 percent higher than today’s – for freight transport in Germany alone in the year 2030. It won’t be possible to move this huge amount on the road – and even with the help of rail freight transport, only if it operates much more efficiently in the future. This is why one of the German government’s explicit goals is to expand the rail network and increase its share in the rail/road/shipping transport mix – both for economic reasons and under pressure to translate rail’s significantly improved environmental footprint compared to trucks into concrete reductions in CO₂, nitrogen oxide and particulate matter emissions.

The rapid implementation of this plan has proven difficult because one thing is slowing down productivity: the screw coupling, which is now almost 160 years old. The high degree of manual effort required during marshaling with this component has long since become a major obstacle negatively impacting the competitiveness of European rail freight transport. It needs to be replaced with an automatic coupling that speeds up marshaling and makes it possible to form longer trains and thus increase transport capacity. This has been common practice in the passenger sector for decades, where the Scharfenberg coupler fulfills this role and makes it possible to couple and uncouple any type of train – from trams to bullet trains – quickly, easily, and safely. In the freight transport sector, it is also important to prepare for digital technology in order to simultaneously lay the foundation for the intelligent freight train of the future. And last but not least, automatic coupling increases occupational safety, since railroad workers no longer have to spend any time between the cars.

This is why railroad associations and industry associations – including the Technical Innovation Circle for Rail Freight Transport, the German Railway Industry Association, the Association of German Transport Companies, and the International Union of Wagon Keepers – are pushing for all of Europe to switch to using digital automatic couplers (DAC). “With the new coupling technology, we are combining the long overdue automation of railroad car coupling with the world of Rail 4.0 in a single step,” argues Malte Lawrenz, Chairman of the Association of Freight Car Owners in Germany.

What still sounds like fiction has, in fact, long been the reality in Switzerland. There, SBB Cargo and Voith are proving that the automatic freight coupling works in day-to-day operations. Since May 2019 in the Alpine Republic, 25 locomotives and 100 railroad cars – connected by Voith’s CargoFlex couplers – have been in regular intermodal service, in which containers are loaded from truck to rail. It is based on the tried-and-tested Scharfenberg Type 10 coupler used in passenger transport and, thanks to its zero-backlash design, is the first freight coupler that can be equipped with an automatic uncoupling system and signal or power transmission. This makes fully automated processes, as well as the ability to relay signals and provide power to electrical consumers, possible. “We are the only supplier in Europe that has an automatic freight coupler in regular operation based on the current migration strategy,” says Niklas Weidert, Key Account Manager Freight Couplers Rail EMEA at Voith.

The Swiss decided to invest in technology at an early stage in order to become more competitive and counter the shortage of shunting staff. In this context, the focus wasn’t only on automation, but also on reducing maintenance costs, for example by eliminating the side buffers and thanks to the maintenance-free buffer coupler on the CargoFlex. “Voith uses proven design principles in its freight couplers and deliberately avoids bolted connections in the load path that require maintenance” explains Jessica Amberg, Project Manager 5L Train at SBB Cargo.

The efficiency gains made possible as a result of automatic coupling are distributed among all market participants. “With longer, heavier, faster trains, infrastructure companies benefit from increased capacities, while operators can cut their operating and shunting costs,” explains Voith Manager Weidert. “For wagon keepers, the amount of maintenance required is reduced due to the lack of buffers and less wear on the wheel sets, because the automatic coupling with a stabilizing joint reduces the forces applied between the wheel and rail during cornering. And shippers can acquire new customers thanks to the higher payloads per wagon and train.”

According to a study carried out on behalf of Germany’s Federal Ministry of Transport and Digital Infrastructure, however, preliminary calculations indicate that between 432,000 and 485,000 freight cars will have to be converted in Europe, including England, Norway, and Switzerland, when migrating to digital automatic couplers. In addition, around 17,000 locomotives will be equipped with an automatic coupler. During a transitional period, Voith will also offer the CargoFlex for locomotives as a hybrid version that, thanks to its head that can be swiveled up, can also be used as a mixed towing coupler with a draw hook.

Because of the cost of retrofitting, SBB Cargo CEO Nicolas Perrin called for European standards to be created as soon as the pilot project for the automatic coupler was launched. “The joint approach will allow us to collectively drive the freight transport sector forward and reap the benefits equally,” says the executive. At the beginning of 2020, six rail freight transport associations signed a charter in which they called on policymakers and the industry to join forces and “place a focus on the digital automatic coupler as a key technology for efficient Rail 4.0.” The goal is to have freight cars throughout Europe automatically coupled and digitally connected, from the locomotive to the last car, by 2030 at the latest. Automated marshaling and brake testing would then become a reality, as would digital integrity testing and load monitoring.

Until then, the SBB freight subsidiary will expand its pioneering role with the help of the Voith CargoFlex, based on its experience gained in day-to-day operations. “Everything has been running smoothly since the automatic coupler was introduced,” says Jasmin Bigdon, head of Asset Management at SBB Cargo. As a result, her company plans to gradually switch all of its intermodal domestic freight trains to the automatic coupler starting in June 2021.