www.profeng.com
The home of
Professional Engineering
on the web
Professional Engineering
Home
Current Issue
News Extra
Tech extra
PE Blog
PE Extra
Letters
Archive
Search the Archive
About PE magazine
Contact
Search our back issues
Search
Subscribe to Professional Engineering magazine
Request a media pack
Our other magazines and journals:
Automotive Engineer
Engineering Opps
PEP Journals
TopEngineeringJobs.com
Related links and resources
PE Archive pre-2008
IMechE
Return to:
Prof Eng Home
Archive
2008 Issues Archive
26 November 2008
Print Page
Weak joint blamed for Cern fault
The breakdown two months ago of the Large Hadron Collider, the world’s largest particle accelerator, is believed to have been caused by a soldered joint. The incident happened just days after it was switched on at Cern in September.
The 27km collider or LHC sits 100 metres underground on the French/Swiss border and is designed to solve some of the mysteries of the universe.
It is powered in eight sectors, each about 3.3km long, with a busbar running through the whole of the sector to carry current for the bipolar magnets.
Investigators found that one of the interconnecting cables on the busbar failed at around 9,000 amperes.
A spokesman for Cern said: “The resulting arcing caused a breach in the tube carrying the helium that keeps it cold. That helium escaped, became gaseous and developed pressure, which is what caused mechanical damage.
“There was a whole chain of events set up by this but the original cause appears to be a faulty solder joint.”
A team of technicians has hauled a number of magnets to the surface to inspect for damage and repair.
The team is said to be making good progress with the first repaired magnet due to be reinstalled later this month. Engineers are putting in systems to make sure the fault does not reoccur.
Cern said: “There are around 50,000 electrical connections. We are looking at every single one.
“The repairs will be done as soon as possible. Summer 2009 is as early as possible but if it takes longer to do it right, we will.”
The repair budget is just over £8 million, with a further £5 to £10 million being put aside to restock spare parts.
© PE Publishing, 26 November 2008
