Application of advances in manufacture techniques to replacement components on JET NI beamlines

Since the first procurement phase of JET in the late 1970's and early 1980's advances in manufacturing techniques have rendered obsolete same of the original methods of producing some JET components. Set against this background the the neutral injection beamlines have been operating since 1986 with ever increasing demands such that their performance is now at 160% of the original design parameters. This enhanced performance over an extended period, combined with tritium contamination, has necessitated the evaluation and reanalysis of all original high-risk components where fatigue and/or operational limits may have been reached. The application of new techniques and a value engineered approach can produce not only higher performance, more robust and accurate components but can, in many cases, result in significant cost reactions. Two such components will be discussed, namely extraction grids and ion source bodies of the PINI system.