Monitoring of damage on water–cooled cables installed in the Large Hadron Collider (CERN) and research on possible alternatives.

To supply the superconducting magnets in the Large Hadron Collider at CERN, several thousand metres of water–cooled cables were installed. These cables consist of a flexible copper core surrounded by a reinforced rubber hose. Although the hose material has been selected carefully, on many cables the rubber hose has suffered from damage. After giving a general overview on common rubber materials and known reasons for their ageing, the technology of water–cooled cables and their special requirements will be introduced. Then, the aim of this thesis is to present the monitoring of the damage on the rubber hoses. This includes an introduction to the monitoring technique used, followed by an analysis and discussion of the results obtained. As a different way of investigating the damage, a pressure test for the rubber hose will be proposed and specified; and the possibility of using alternative conductors for the current supply of the LHC main magnets will be examined. Finally, a series of radiation tests on potential new materials for rubber hoses will be presented.