IPP Annual Report 2007 - Max-Planck-Institut für Plasmaphysik ...

They have to transmit forces up to 500 kN and to reduce
PLC deformations to tolerable values. A final solution was
found for the fixed supports of the planar coils which replace
one of the previously foreseen sliding elements per coil.
4.1.1.2.8 Contact elements (CTE)
The contact elements are, similarly to the NSEs, sliding
supports between half-module and module interfaces which
transmit compression forces via MoS 2 – coated Al-Bronze
Pads and steel counter-surfaces. In contrary to the NSEs,
the gap width adjustment is possible only after final positioning
of the half-modules and modules, resp., which
requires special provisions. The designs of the contact elements
were finally frozen, and a functional specification
was issued.
4.1.1.2.9 Current lead fixing box
The current lead support structure (“fixing box”) was modelled
and analysed at the IPP, and incorporated in the global
model of the bus-bar system (FZJ, Jülich). The optimisation
of the structure is still on-going.
Figure 16: Analysis of current lead fixing box; deformation in mm
4.1.1.3 Cryo piping
FE-modelling (in ANSYS) of the cryo-pipe work for the
first module to be assembled has started in close cooperation
with the design group. The aim of this work is to determine
Wendelstein 7-X
42
mechanical loads and deformations of the complex piping
system as a consequence of the magnet system movements
during cool-down and magnet excitation.
Z
X Y
Figure 17: Finite element model of cryopipe system for module 5
4.1.1.4 Cryostat
The ANSYS FE cryostat global model refinement and
update in cooperation with IGN and ENEA (cooperation
was closed in 2007) is practically completed, and the model
is operational from the beginning of 2008. The final update
was a consequence of the Scenario 3 implementation which
requests omission of 45 ports. Concerning the improved
horizontal plasma vessel (PV) support system, the common
work of IPP and Rostock University on a procedure for controlled
adjustment and shaping of the plasma vessel within a
range of ±10 mm was completed. The result is an iterative
approach using the algorithm of Rostock and the cryostat
GM of IPP. An accuracy of