Remote handling mock-up trials of replacement of a JET neutral beam ion source

During the D-T phase of JET (Joint European Torus) it is planned to undertake maintenance using remote handling (RH) equipment. The equipment necessary to undertake this has been progressively procured and the first full-scale RH task mock-up trial was undertaken. The authors describe the results and experience gathered during this activity. Replacement of a neutral beam ion source was chosen for mock-up for a number of reasons. Firstly, it is expected that the task will be required to be done during the D-T phase and secondly it includes a comprehensive sample of the remote operations expected in the ex-vessel tasks. Consideration was given to tasks such as operation of fasteners, electrical power, and control connectors, quick release fluid couplings, lip weld flange cutting and welding, special lifting and alignment fixtures, and both manual and powered tools. Included within this work are operations with high levels of difficulty due to very limited access and viewing constraints. The experiences from undertaking this work resulted in a number of modifications to the remote handling equipment, the neutral beam ion source design, and the operational procedure