Posted on: 8th March 2013
The JET shutdown is progressing steadily. Remote Handling Group has been working in-vessel since December. The first task was to conduct a full photographic survey of the inside of the vessel, so that the effects of a year of plasma operations on the ITER-like wall can be assessed. Scientists are now poring over the photographs in detail.
Meanwhile various components have been removed from the torus for closer examination. The tiles in the divertor region (at the bottom of the torus) are fixed to ‘carriers’, and around 20 of these carriers have been removed. They have been transferred to the Beryllium Handling Facility for maintenance of some of the embedded diagnostic systems and removal of a few tiles.
About 600 individual tiles and components have also been removed. Most of these will be replaced without modification, but it was necessary to remove this number in order to gain access to about 50 in particular regions of interest. The 50 will be analysed in laboratories around Europe to look for evidence of erosion and deposition. As many of the tests will be destructive, they will be replaced by brand new tiles as the 600 are re-assembled. Already more than half the tiles taken from the poloidal limiters are back in place.
The next instalment will cover calibration of some diagnostic systems.