In 1885, Messrs. Schmidt and Kranz established the Schmidt, Kranz & Co. GmbH, a company producing tunnel drilling machines and shaft sinking equipment for the potash and salt industry. In 1928, Professor Karl Glinz acquired the company and extended the product range to tractors (Normag) and the manufacturing of various products for the coal mining industry. 

Mining engineer Dr. Hans-Karl Glinz took over the management of the company in 1937, extending the product-range with drilling machines for gas drainage and production. 

His son, Dr. Hans-Caspar Glinz, joined the company in 1981. He integrated hydraulic and pneumatic products into the portfolio, branded as ‘Maximator’.

During his tenure, the company had been reorganised into a holding structure: Schmidt Kranz continued as the holding company for the group. The brands Perforator and Maximator were transferred into independent subsidiaries. Through further acquisitions, including Hazemag, GHH and Fest, Schmidt Kranz quickly grew into a German medium-sized business group.

The next generation came on board in 2010. Mortimer Glinz and his sister Pia-Sophie Yankah were the fourth generation of the Glinz family to join the business. Today, Mortimer Glinz manages the newly branded SK Group together with his father, Pia-Sophie Yankah is chairwoman of the board. Together they explore new markets and technologies and set the scope to lead the group to organic growth.