The Latest from the LHC

The campaign to install the new helium pressure release system is progressing well. The first sector to be fully completed is 5-6, with all 168 individual pressure release ports installed. These ports will allow a greater rate of helium escape in the event of a sudden increase in pressure of the insulation vacuum. To install them the teams had to initially open the ‘W bellows’ – the large accordion-shaped sleeves that cover the interconnections between two magnets. Now that all the pressure release ports have been fitted, these ‘W bellows’ can start to be closed up again – marking the end of the consolidation work in 5-6. Preparations are starting to be made to cool the sector down: this week the first three ‘vacuum sub-sectors’ have been sealed. Each sub-sector is a 200 metre-long section of the insulating vacuum chamber that surrounds the magnet cold mass. Once sealed the sub-sector is pumped out and tested for leaks.

The damaged area of Sector 3-4 is buzzing with activity. Teams are working through the night and on weekends to install the replacement magnets at a rate of 6-7 per week. With more and more magnets installed and aligned, the pace of the work to join all the various connections from each magnet to its neighbours, has increased sharply over the past few weeks: for example, the soldering of electrical joints has gone up from 2 to 8 interconnects per week within a fortnight.

Work to fit the replacement magnet in Sector 1-2 has been completed. This magnet replaces one that was found to have high internal resistance and was previously removed (see previous update - https://cds.cern.ch/record/1158758?ln=en).