Railway technician is a well-defined job

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NEWS daily newspaper Junge Welt3, Berlin, Germany
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25.07.2008

Shorter lifespan

Professor Vatroslav Grubisic, also known as the "Wheels Pope", sees the serious danger that the Cologne train accident was a "harbinger" of further ICE 3 wheel shaft breaks

From Winfried Wolf

Vatroslav Grubisic assumes that the ICE-3 axis that broke on July 9th on the Hohenzollern Bridge in Cologne suffered a "fatigue break". He "largely rules out" a "force break", a destruction of the axis by external influences. Vatroslav Grubisic made this statement in the previous year in the mirror. In an interview with Junge Welt, he adds: "Everything will be done to present the accident as a violent rupture and thus a one-off event." That is how it was in the past, and that is how it can now be dealt with again. And that is how it was handled. Although the online portal of the Hamburg news magazine brings the quoted Grubisic statements. But in the current print edition only the thesis of a »violent breach« is represented (see below).

Distinguished specialist

Who is this Grubisic? A black painter? A train hater? A braggart? That can be denied three times. In fact, Professor Vatroslav Grubisic is one of the most prominent experts in the field of railway technology. He likes to travel by train a lot - but now he doesn't really like taking the ICE-3 anymore. Grubisic is 75 years old today. From 1961 to 1996 he worked in various functions at the Fraunhofer Institute in Darmstadt, including as a specialist in the reliable dimensioning of vehicle components and most recently as deputy director of this prestigious institution. It was he who, together with his colleague Dr. After the ICE accident in Eschede ten years ago, Fischer found the torn off wheel tire, which got wedged in a switch, changed it and caused the high-speed train to derail. He later represented the Fraunhofer Institute in the Eschede trial. His work in Eschede and his decades-long presence in specialist magazines may have contributed to Grubisic being referred to in specialist circles as the "wheel pope".

Now the Deutsche Bahn AG - most recently again to the ZDF magazine "Frontal21" on July 22nd - declared that the ICE-3 had already traveled "billions of kilometers by train" and that there had never been any major problems, especially not those with them Axes given. That is "nonsense of the first order," says Grubisic. It is uninteresting how many added train kilometers an ICE fleet has behind it. This could only be about individual values ​​- of each wave. The material fatigue is exclusively a "time-dependent quantity". The wave that broke in Cologne was apparently "in use for seven or eight years." According to his calculations, this is »clearly too early« for an axle break. The Deutsche Bahn AG and the manufacturers, however, assume a service life of the wheel shafts of 30 years. Grubisic now considers this to be “extremely unrealistic”.

Grubisic sees a threatening scenario: what we experienced in Cologne was - if it was a "fatigue break" - a "harbinger". In the case of a fatigue fracture, the cracking had "progressed for months"; the wave must then have "started much earlier". Then, however, the other ICE 3 axles would also be affected. From the break in Cologne it must be concluded that all ICE-3 axles have a significantly shorter lifespan, that most of them could break in the next few days, weeks, months or at least in a few years.

Grubisic sees the loads to which the wheelset shafts of high-speed trains in Germany are exposed at different levels, the special thing being that the different types of load represent an extremely complex matter, and their interaction and interaction could hardly be precisely calculated. There are the normal stresses caused by the high speeds, which are now up to 300 kilometers per hour in the German rail network. Obviously there are relatively safe design methods for this type of load. In addition, however, the new multiple units, such as the diesel ICE-TD and the ICE-3, are subject to special loads on the drive shafts. Finally, there is the special feature in Germany that the high-speed trains not only run on specially developed routes, but to a large extent also on the route network for conventional rail traffic. Grubisic in conversation with Spiegel online: »The TGVs in France run on a route that is only designed for high-speed trains. There the loads on the axles are lower and the axles are still stronger. "

Neutral opinion

Now, on July 20, the railway announced that all ICE-3 axles had been checked with ultrasound and that "no further abnormalities" had been registered. Therefore, all ICE-3 trains are now in use again. So everything is OK and on the safe track? Grubisic is skeptical that ultrasonic testing is sufficient in this situation. "Trains that run at these speeds and that are exposed to such complex loads" cannot "be evaluated using the old means," says the "Wheels Pope" to Junge Welt. He had published proposals, including in the specialist journal Eisenbahntechnische Revue (March 2006), which scientific, supplementary methods should be used to carry out such tests for freedom from cracks. Incidentally, it is to be viewed critically when Deutsche Bahn AG checks itself - with all the pressure it is under with a view to the imminent IPO. “A neutral expert is required.” The Federal Railway Authority is also only an option to a limited extent - the EBA officials are “themselves under enormous pressure” exerted by DB AG and often also by the Federal Ministry of Transport.

“You know,” says Grubisic, “the then rail technology director at Bombardier Transportation, Wolfgang Tölsner, once said in an interview with the Frankfurter Rundschau: 'Trains can't be sold like green bananas.'” At that time, it was about the disaster the tilting technology trains, which had to record serious failures for years after delivery to the railway. Grubisic continues: “But that's exactly what is happening. They let the trains mature for the customer. Maybe you can do that by selling toilets. But not when it comes to goods on which the life and limb of thousands of people depend. "

The uniqueness thesis

The Hamburg news magazine Der Spiegel reports in its current issue 30 under the title “Hesitant investigation” on the Cologne ICE accident: “Experts consider a material fault to be largely ruled out. ›Everything speaks in favor of external damage to the wheelset shaft, for example from loose metal parts of the train underbody or objects on the track,‹ says Dresden Professor Günter Löffler. ›That would also explain why travelers heard noises on the route between Frankfurt and Cologne before the accident.‹ The wave itself only broke when the train started, because that's where the greatest load occurs, he suspects. Engineers at Deutsche Bahn also consider this explanation to be likely. The company says that 'no cracks' have formed on the axle so far during the regular inspections. "

As a result of the derailment of a high-speed train at Cologne Central Station on July 9, almost all ICE-3s were taken out of service for ultrasound examinations of the axles. The Deutsche Bahn AG had initially refused to have all identical trains of the so-called third generation examined immediately for defects. The responsible supervisory authority EBA (Federal Railway Authority) had to formally instruct the relevant inspections on July 11th. 40 hours after the accident in Cologne, the ICE 3 fleet was withdrawn from service. On Sunday, the railway reported that the inspection of the 61 trains had been completed and that there were "no abnormalities". (jW)