A Century on Track

Both rolling stock and infrastructure have to withstand increasing demands. Predictive maintenance is a way to envision and respond to these demands. And here in particular, ZF sees a way to make use of digitalization. At InnoTrans 2018, the company presented its condition monitoring system “connect@rail,” starting the pilot project with partner Graz Linien in the same year. As a comprehensive condition monitoring system, “connect@rail” combines digital know-how, integrated sensors, advanced data analysis and intelligent connectivity solutions for rail transport. Because it identifies early on damage to the driveline and track infrastructure, “connect@rail” enables efficient maintenance planning. This prevents downtime, enhances safety and helps to make rail mobility as trouble-free as possible. Since its initial use, further orders for the ZF system have followed, as well as strategic partnerships to expand the possibilities of “connect@rail".

There is hardly a scenario in science fiction in which urban mobility does not (also) take place high above the streets. But the future was already there in the past. In Wuppertal, for example, the suspension railway was launched back in 1901. In the 2010s, a pan-European consortium of companies revised this retro-futuristic mode of transportation. The new suspension railway was commissioned in 2015. With secondary dampers from Schweinfurt and a specially developed, highly integrated bevel spur gear transmission from Friedrichshafen, whose oil pump also supplies all rolling bearings and gears with sufficient lubricants. In this way, ZF supports an “old” vision of the future in meeting today’s mobility requirements.

Even aging rail vehicles do not necessarily have to be scrapped. This is the key idea behind repowering. This service, which the ZF Aftermarket Division has been offering since 2010, replaces the entire driveline of existing fleets with modern, efficient technology. This increases safety and extends the service life of rail vehicles. And proves that good technology always has a future.

With ZF damping, the first Velaro (a further development of the ICE 3) traveled safely through Spain at speeds of up to 350 km/h in 2004, followed by variants for Russia and China in 2007. The Middle Kingdom proved to be a particularly successful market for ZF.

ZF develops into an overall supplier and system supplier for railway technology. Since the acquisition of Sachs AG in 2001, chassis technology also becomes part of the area of expertise in railway technology. In the truest sense of the word, ZF is “everywhere on the train".

In 1996, it bundled the competencies of “Basic Development” for damping technology in the Schweinfurt Development Center.

In 1995, ZF took over its competitor Hurth from Munich. This created a full-range supplier in rail driveline technology, which is now regarded as the preferred partner of manufacturers and transport associations worldwide – thanks also to the connection to the global service network of ZF Aftermarket.

In 1992, the company founded a Center of Excellence for rail vehicle dampers in Eitorf.

In tune with ZF’s strategy, global markets can best be opened up with a global presence. As a result, the company has been increasing its involvement in the important markets of the United States and China since the mid-1990s. This included the opening of development and production centers around the world – for example, in Gainesville (Georgia, USA) and in Beijing. In this way, ZF remains close to the customer, in accordance with the “local-for-local” philosophy.

With the tendency for more speed, the hydraulic damping and the yaw dampers proved successful across the board. From the 1980s onward, these developments were accelerated in Germany by the first ICE rolling stock, which was equipped with ZF dampers from the outset. But there were also innovations in local transport, with trams increasingly featuring a low-floor or modular design, which then needed new damper designs.

ZF turned to one of its best-selling powershift transmissions, the ZF-Ecomat, for use in rail vehicles at the end of the 1970s. Just like the much more efficient automated commercial vehicle transmission AS Tronic in the guise of the AS Rail or like today’s uprated EcoLife Rail 2 and EcoWorld 2 transmission with integrated reversing stage.

In the 1960s, both ZF and Hurth supported the electrification of the German rail network with complete transmissions (including clutch) for local trains and locomotives with electric and electrohydraulic drives. The Stuttgart trams, which snaked up and down the steep slopes of the state capital of Baden-Württemberg, are just one example that illustrates the performance of these drives. Even today this remains one of the most demanding topologies for rail vehicles. The use of a differential was also a veritable first on the market and attested to the engineers’ ingenuity.

The first rail vehicles were equipped with dampers under the Boge and Sachs brands - two brands that later merged into ZF. One of the first example is the "Uerdinger Schienenbus" of the DB series VT95, a diesel-powered light railcar for passenger transport on branch lines. At the same time, the first trams were also equipped with dampers, opening up another business area.

In the 1950s, Hurth began to apply its know-how to rail vehicles – initially as a specialist for gears and as a component supplier, and from the 1960s onward as a full-service supplier of rail transmissions. Hurth focused much more than ZF on transmissions that are directly connected to the rail vehicle axle. This design could be used on both diesel-powered and electrically powered railways. Since the 1970s, Hurth has benefited from the growing uptake of trams, metros and commuter trains in major cities around the world. The technology was also suitable for electric locomotives for express trains for Deutsche Bahn, and SNCF in France. The most high-profile Hurth application, in a sense, drove “underwater” – through the Eurotunnel, which connected England to the continent.

Around the world, everyone wants safe, reliable and comfortable rail services. Fulfilling this is the motivation behind ZF’s development services. That is why there is a search for proximity to markets, to vehicle manufacturers, to passengers. And that began in 1927. The Budapest company Schlick-Nicholson presented the Hungarian State Railways with a twin-axle internal combustion railcar outfitted with a Soden transmission.

ZF adapted the TS18.5 Soden transmission - a technology that was primarily meant for passenger cars - for internal combustion railcars.