The medium rolling mill in Hällefors is a remarkable site with great industrial history behind. It all in 1639 with development of silver mining and processing.
The production of steel followed later, by the end of the 18th century.

The original company Hellefors Bruck AB became part of the Wargön Group in 1915. In 1958 Billerud bought it, but sold it to SKF soon after.

The unique medium mill was commissioned in 1977 and it is now operated by Ovako who runs the plant since 2005.