Preliminary configuration of the torus vacuum pumping system installed in the DEMO lower port

In the European DEMO program, the design development of the demonstration power plant (DEMO) is currently in its pre-conceptual phase. This work includes also the design development of the vacuum vessel, where lower ports are important appendices that include the primary vacuum pumping systems as major components of the vacuum pumping and fuel processing systems. This paper develops a preliminary design configuration of the primary pumping systems. It starts with a definition of requirements on which basis the design of this so-called 'pump cask design' is evolved. Furthermore, this paper states clearly what work is required in order to come up with a sound pre-conceptual design for DEMO in 2020 and a conceptual design in 2027.