New operational aspects of the ITER-FEAT primary vacuum pumping system

At Forschungszentrum Karlsruhe, a special cryosorption vacuum pump system is being developed for ITER-FEAT. The available R&D and design work performed so far originally supported the ITER-FDR machine, but only minor redirection has been needed. However, three new crucial aspects are described and critically discussed in this paper. These are the rather high throughputs per individual pump (which have almost doubled), the poisoning phenomena, and the use of the cryopumps during fine He leak detection. It could be demonstrated that all these aspects generated by the new ITER-FEAT design will not be a limiting factor for cryopump operation.