Thermit®

Railroads that glide (almost) without a sound

Goldschmidt

In the era of high-speed railroads, it’s difficult to imagine the way track was being laid until well into the 20th century. A seemingly endless number of very short, maximum four meter long rail sections were joined with fishplates. As the trains rode over them, they made quick, irritating “clack-clack clack-clack" sounds. The fishplates also represented a considerable safety hazard.

A lasting solution was only found when Hans Goldschmidt developed the Thermit process for welding rail sections together. This method is still used today. However, when he started to subject aluminothermic reactions to scientific investigation in 1893, Hans Goldschmidt actually had something else in mind. He wanted to show what happened when a mixture of metal oxide and aluminum generating 3000°C was applied to carbon-free metals, such as chromium and manganese. He just happened to discover that this created first-class molten steel in small quantities that could be used to precision-weld two pieces of metal end to end, including rails. This welding compound was called Thermit® and was used to weld streetcar track for the first time in Essen. It was a resounding success: When the First World War broke out; the Thermit process had established itself as the worldwide standard for welding streetcar track. In contrast, the big railroad companies held back until the end of the 1920s before starting to use Thermit to make their track safer, more comfortable and faster.

Over the years, Elektro-Thermit GmbH, founded in 1919 as a subsidiary of Th. Goldschmidt AG, became one of the mainstays at Goldschmidt, particularly as the Thermit process constantly underwent development and improvement.

From the 1970s, Goldschmidt addressed itself more and more to specialty chemicals and the Thermit business seemed no longer really correctly placed. VIAG AG became the majority shareholder in Th. Goldschmidt AG in 1997 and in 1999 came to an agreement with the Goldschmidt family: In exchange for their shares in Th. Goldschmidt AG, of which there was still a considerable number, VIAG gave the family the Elektro-Thermit GmbH company. This continued to operate at the Essen site till fall 2006, but then was concentrated at the Halle/Saale site. The former Thermit production building at the present Evonik site Essen/Goldschmidtstrasse was subsequently pulled down in spring 2007.

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