Planning and Controlling of the Cold Accelerator Sections Installation in XFEL

The installation of the main linear accelerator in the 2 km European XFEL (X-Ray Free-Electron Laser) tunnel is currently under way. The accelerator consists of nineso-called cryo-strings. A typical cryo-string comprises 12 accelerator modules, which will be fed by three RF stations. Furthermore, the installation of electronic racks,cables, power and water supply etc. takes place. To enable a most effective installation of the accelerator components, planning and controlling methods, whichhad first been developed for the RF system work package, were adapted for the entire main linear accelerator. As a first step, a process plan was developed in cooperationwith the work package leaders. On the basis of this plan, the installation process is promoted by several measures: The status of the installation is precisely registered byweekly queries which enable monitoring of the Progress and feedback to everyone involved. With this Information at hand, the installation process can be controlled andplan deviations can be corrected. Furthermore, the experience gained at one cryo-string is used to optimise the plan for the next cryo-string installation