Company management

The company has been managed for six generations by the family members and offspring of the founder and namesake Wilhelm Karrenberg. In 1989, following the sudden death of his father-in-law, Friedrich Karrenberg, Wolfgang K. Schlieper was appointed as the managing partner. His son, Robert Schlieper, will carry on the family tradition in his wake.

Who we are, what we do and what drives us. That is WILKA!


Robert Schlieper
Master of Science
Managing Partner
In 2010 Robert Schlieper entered the Velbert-based family company as the 6th generation. He started in the technical section in order to acquire sufficient knowledge of products and production. He continued to manage the company after his father in May 2016
Sascha Köstermann
Certified accountant, Head of Finance and Human Resources
Wolf Sausmikat
Business economist, Head of Sales
Olaf Witte
Qualified engineer, Operating manager