Friedrich Wilhelm zur Weihen, Friedhelm Kreffter, Karl-Ulrich Rinne and Alfons Brune start the Industrieofen & Haertereizubehoer GmbH Unna (IHU).
Alfons Brune leaves the company.
Hendrik zur Weihen, son of the co-founder Friedrich Wilhelm zur Weihen, starts as an employee of the company.Start of the manufacture of shaft furnaces with compensator technology.
Friedhelm Kreffter, Karl-Ulrich Rinne and Hendrik zur Weihen commonly lead the company as managing shareholders.
Hendrik zur Weihen is the only managing shareholder after his partners have gone into retirement.