BUTTING will be playing a part in the construction of Wendelstein 7-X, the world’s largest experiment in nuclear fusion of the stellarator type, currently being constructed at the Max-Planck Institute for Plasma Physics in Greifswald, Germany and should be completed by 2014. For the project, a team from the Forschungszentrum (Research Centre) in Karlsruhe, together with the BUTTING development department and its technical sales staff, worked on an optimum solution approach to the casing and protective pipes of the superconducting power supply line for the fusion plant. The Karlsruhe Research Centre first contacted BUTTING in the summer of 2007, with an initial inquiry about standard pipes, which were to be used as casing and protective pipes. After an intensive dialogue with the customer, BUTTING offered an alternative overall technical solution: the stringent tolerance requirements were realised partly by using precision half pipes, which achieved the required (final) tolerances only after welding. The half pipes in size 126 x 3 x 1077mm were manufactured from material 1.4429 with a permeability of µr GBP 1.01, which was not to be exceeded throughout the entire production process. Afterwards a shrinking of the pipe-ends followed. In addition to the half pipes, BUTTING also manufactured pipe bodies with the dimensions of 180 x 3 x 550mm, 180 x 3 x 1127mm and 277 x 3 x 564mm. The total raw materials of grade 1.4429 came from one heat set up especially for the project. The half pipes and pipe bodies were supplied by the end of June 2008.
