TESTING of the Digital Automatic Coupler (DAC) developed by Knorr-Bremse is underway on a freight train operating in regular traffic in Sweden. The aim is to demonstrate how the automated coupler system can make rail freight more efficient, flexible and competitive as the manufacturer moves towards the market launch of its DAC in 2025.

The test train is operated by Trafikverket and will initially comprise six DAC-fitted vehicles but this is likely to eventually increase to 20 wagons, with the test trains expected to cover around 100,000km a year through to 2025. The tests of the Knorr-Bremse version of DAC will be carried out under the aegis of the European Union’s (EU’s) Europe’s Rail Joint Undertaking (EU-Rail) research and development programme.

DAC aims to simplify rail freight transport in Europe by speeding up handling, operation and turnaround cycles. With a design based on the type 10 Scharfenberg coupler, DAC offers automatic connection of brake pipes along with electrical systems - removing the need for staff to walk thousands of kilometres in all weather conditions while marshalling freight trains.

To begin with the DAC installed on the train will be equipped with support for Automation Level 2 but Knorr-Bremse says it will later be fitted with couplers that support higher levels of automation allowing uncoupling of not only the rolling stock but also a range of intelligent and telematic systems. Knorr-Bremse says testing of the train in the Scandinavian winter, including ice tests, is seen as the ideal durability test to establish whether the coupling system meets the highest standards of resilience.

Knorr-Bremse was confirmed by TÜV-Süd and the European DAC Delivery Programme (EDDP) as an authorised DAC manufacturer in December of last year. DAC is seen as a key innovation to make rail freight more competitive across Europe as currently around 500,000 freight wagons and 17,000 locomotives still need to be coupled manually. With the EU aiming to encourage a substantial modal shift of freight traffic from road to rail, the rail freight sector represents a large future market for automation and digitalisation, with the adoption of DAC couplers playing an important part.

At the InnoTrans 2022 transport industry fair in Berlin, Knorr-Bremse exhibited its new DAC electric contact coupler (e-coupler), stating it was the first concept to satisfy all the requirements of the EDDP specifications, including restricted dimensions, a high level of weather resistance and the ability to establish a connection between delicate electrical contracts safely and gently during the coupling process.