From 1933 to 1939, during his time in
Nazi Germany, Durrer supervised experiments on the new steel making technique.
[2] In 1943 Durrer returned from
Nazi Germany to Switzerland and was appointed to the board of
von Roll AG, the country's largest steelmaker.
[1] Durrer teamed up with
Heinrich Heilbrugge and ran a series of experiments that established commercial viability of basic oxygen metallurgy.
[1] In 1947 Durrer ordered a small experimental converter from the United States, and on 1 April 1948 Durrer and Heilbrugge produced their first oxygen-blown steel.
[1]
In the summer of 1948 von Roll AG and two Austrian state-owned companies,
VÖEST and ÖAMG, agreed to commercialize the Durrer process.
[3] Their commercial converter furnaces were put into operation in November 1952 (VÖEST in
Linz) and May 1953 (ÖAMG, Donawitz)
[4] and temporarily became
the leading edge of the world's steelmaking, causing a surge in steel-related research.
[5] Unlike Europe, whose industrial capacity had been decimated by
World War II, America had a large base of steelmaking capacity, and it was economic to retain, rather than replace, its capital stock.