Overview of the KSTAR vacuum pumping system

The installation of the Korea Superconducting Tokamak Advanced Research (KSTAR) device vacuum pumping system for both the vacuum vessel and the cryostat was finished in the middle of 2007. After the successful self-commissioning of the main vacuum pumping system by August 2007, the system successfully operated in the integrated system commissioning and 1st plasma experiments of the KSTAR device. The vacuum pumping system has successfully operated and achieved the target vacuum pressure for the vacuum vessel and the cryostat during the machine commissioning and 1st plasma experiments with no severe troubles and problems, which is one of the main factors that led the KSTAR project to achieve successful 1st plasma. Furthermore, the vacuum pumping system has been satisfactorily operated by remote control and synchronization in gas puffing experiments. This paper describes the final configuration of the KSTAR vacuum pumping system, the results of vacuum commissioning, and the other results of the vacuum conditions that relate to wall conditioning.