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In the Large Hadron Collider (LHC), presently under construction at CERN, about 1200 vacuum chambers, corresponding to roughly 6 Km of beam pipe, are being coated on the whole inner surface with a thin Ti-Zr-V film. After in situ activation at temperatures higher than 180°C, this non-evaporable getter (NEG) coating provides a large distributed pumping speed and reduced secondary electron yields allowing the suppression of electron cloud instability effects. After a brief review of the NEG film properties, the first results obtained from a prototype and vacuum sectors already installed in the LHC tunnel will be presented. The chosen bakeout cycle, the problems encountered during activation, the acceptability tests, and the main limitation of the measured pressures will be address. |