In recent times, much attention is paying to the automatic coupling of freight wagons, as has long been the case with Dmus and Emus. But why has Europe fallen so far behind?
The fact is simple: every continent in the world has had an automatic coupling of one kind or another for a long time. If Europe is lagging behind, it is for historical and commercial reasons.
Railway coupling appeared as soon as the “train” was invented, even when it was still by horse traction. It was first made of chains. But this system is problematic, especially in slowdowns. Buffers are added to absorb shocks between wagons. But these manual couplings also show another face: the number of accidents recorded during train formation operations. This aspect was already very much present as early as the 1900s and in international seminars. It was therefore imperative to reduce the number of accidents.
In the 19th century, European engineers were already interested in the application of automatic couplings in Canada and the United States. In the USA, Janney couplers are a semi-automatic design were first patented in 1873 by Eli H. Janney. Prior to the formation of the Association of American Railroads (AAR) these were known as or Master Car Builder (MCB) couplers. In 1934 the MCB was renamed as the AAR. Of course, these couplings were only widespread in one country, this makes it easier to deploy it on a large scale. In the UK, several versions of these Janney couplers were fitted to a limited number of coaches, multiple units, wagons and locomotives.
In Europe, railways rhyme with “nation”, and in these troubled times at the end of the 19th century, automatic couplings became a geopolitical issue, particularly between France and Germany. Thus, in spite of the creation of the UIC in 1922, the measurement of the risk incurred during the wagon coupling manœuvre became the object of conflicts between different actors, unable to agree on a matter that was nevertheless a matter of science. But the automatic coupling, like the braking of trains, was also the subject of union resistance. These improvements reduced working time and cut jobs. The UIC has never been able to agree with everyone on this subject. A debate reminiscent of today’s, with digitalisation!
The Scharfenberg coupler (also knows as ‘Schaku‘) belongs to the central buffer couplers. The coupler was developed by Karl Scharfenberg in Königsberg (today Kaliningrad), and received patents for it in 1904 and 1907. The Scharfenberg coupler is a multi-function coupler functions without the need for human intervention, as both the coupling mechanism and the air hoses connect automatically. It is the only European success story in train coupling.
The ‘Shaku‘ is only used around the world in passenger trains of all kinds, from trams to high-speed trains, and can be found today in almost all state railways. It was unfortunately never accepted for freight wagons. In 2002, type 10 of the Scharfenberg coupler was declared the standard for high-speed trains and is now part of the interoperability specification (TSI).
Europe had nevertheless opted for the screw coupling, which requires manual operations: tightening the coupling and, separately, coupling the brake lines (and electric cables for passenger cars).
This was the failure of the UIC in the 1930s, which hampers freight operation in Europe even today, led to the decision by the Soviet Union to move forward without a standard being achieved in the talks. The coupler was developed in 1932 and named SA-3. In 1935, the conversion of the vehicles began gradually but the Second World War delayed the introduction, so that the full conversion of the russian rolling stock was completed only 1957.
In the 1960s, the UIC tried to revive the automatic coupling.But the lack of consensus and, above all, the number of freight wagons already fitted with the standard UIC screw coupling did not militate in favour of further studies. Wagon owners felt that the costs of conversion were too high in relation to the expected gains.
Nevertheless, the German industrialist Knorr Bremse tried an automatic wagon coupling to reduce the time and cost of coupling and uncoupling operations in shunting yards, by proposing a less expensive automatic coupling with which networks – and private individuals – could equip their wagon fleet on demand and/or on strict need, while maintaining the compatibility of the rest of the fleet. This project, named Z-AK in Germany, and designated AAST in France (Couplage Automatique de Simple Traction), had no future.
The currently global landscape for automated coupling is:
One might wonder why, in 2020, automatic couplings on freight wagons are presented in Europe as “a great technological advance”… According to the American magazine Railway Today, Americans are sensing that « European counterparts may leapfrog us, with a technology called DAC, for Digital Automatic Coupling. » What exactly is this about?
Very late at the mechanical level, Europe could indeed come back to the forefront by adding a digital layer to the automatic coupling. It makes a big difference. Especially in view of the fact that this innovation is only part of a more general concept, linked to the digital freight wagon. The Europeans recognize that if they want to grow rail freight traffic beyond the meager market share it presently commands, they need to be innovative, and aggressive with modern technology. With a touch of humor Sigrid Nikutta, head of DB Cargo freight activity at Deutsche Bahn, says she is happy that railway was so far not been able to find an automatic coupling: « Today the railway companies and industry want to take two steps in one and combine automatic wagon coupling with the digitization of freight transport. »
A consortium known as DAC4EU was set up and includes six public and private freight transport companies which will be testing different coupling options over the coming years: RCG (Austria), DB Cargo (Germany), SBB Cargo (Switzerland), and the freight wagon leasers Ermewa, GATX Rail Europe and VTG. The consortium is led by Deutsche Bahn AG. The pilot project was awarded by The Federal Ministry of Transport and Digital Infrastructure (BMVI) for around 13 million Euro over the next two and a half years, and began in July 2020 and will run through December 2022. It is however curious that France (excepted the company Ermewa), Italy and Sweden are absent from this technological challenge.
The aim consist to embark on a pilot digital automatic coupler program for freight cars. DB Systems Engineering has install this new system on several freight cars at its wagon facility in Minden, Westphalia. A dozen freight wagons will receive 4 different types of automatic digital couplers and will be tested for two years. A train of 24 wagons will then have to be trained with the technology that will be choose to verify the implementation in real operation. Four manufacturers are currently developing a DAC couplers with three different coupling heads:
- The Scharfenberg type coupler produced by Voith
- The Schwab type coupler produced by Wabtec
- The SA-3 coupler produced by CAF
- and the Dellner coupler
The future automatic coupling chosen will of course be built by the four suppliers participating in the tests. The project is ambitious. The industry hopes to convert all freight rail traffic in Europe to automatic coupler by 2030, including with digital capabilities to operate intelligent freight trains. The automatic coupling is indeed an essential part of the digitization of rail freight. It helps form data lines that run through the entire train to provide information on brakes, train composition and technical issues. And in the future, the dispatcher will not only know where is a chemical wagon, but also what is the temperature of the tanks. The choice will then be binding for hundreds of wagon owners companies in Europe. It is estimated that around 500,000 wagons are affected in continental Europe.
However, it will be necessary to be very attentive to the costs: we have already seen the strong reticence of the operators with ETCS, which they consider too costly for very little operational benefit. In this case, the price of the future coupling and installation of the digital data line will be essential, when we know the value of a 20-year-old freight wagon, which is not high.