Hans Overeijnder has studied physics at the Technical University of Delft (Netherlands). From 1974 till 1978 he has investigated the sputtering of alkali halides with ions and electrons at the Stichting Fundamenteel Onderzoek der Materie (Foundation for Fundamental Research into Matter) in Amsterdam. Starting 1978 he joined the Wavin group where he worked as a process technical engineer. His work was dedicated to the development of new pipe concepts and the optimization of the extrusion process. Since January 2016 Hans is retired.