CERN uses cooling tubes from Fine Tubes for discovery of Higgs boson

Posted on 20 Jul 2012

Plymouth-based Fine Tubes has developed a product with scientists at CERN in Switzerland for the Large Hadron Collider which can stand up to temperatures close to absolute zero (-273.15°).

It’s not often a product is required to perform under conditions of deep outer space but the CERN experiments, replicating conditions believed to have been at the time of the Big Bang demanded just that.

At the beginning of July, physicists at CERN using the Large Hadron Collider reported that there is a high probability they have identified the most elusive sub atomic particle, a boson, which they believe may be the Higgs boson.

Fine Tubes made precise cooling tubes for the extremely low temperature vacuum system at the centre of the Large Hadron Collider, emulating temperatures in deep outer space.

The tubes had to be made from a material that could handle the pressures and extreme temperatures involved and meet a raft of stringent technical requirements, including very high metallurgical cleanliness, very strict leak tightness and exceptionally low levels of inside and outside diameter halogen contamination.

Fine Tubes have been supplying CERN with a product that took years to develop, selling more than a hundred kilometres of tubes, seamless, precision-drawn in specially formulated austenitic stainless steel.

The alloy maintains high mechanical strength and provides very low magnetic permeability at the exceptionally low temperatures – an essential quality as the tubes carry a flow of supercritical helium at high pressure.

Fine Tubes started looking at CERN’s needs over 15 years ago, and developed unique tubing to extremely unusual specifications.

At more than 27km circumference, the Large Hadron Collider is the largest hi-tech machine in the world, yet it demands precision to microscopic levels on some of its components.

Brian Mercer, sales and marketing director commented: “You don’t often need products to perform at temperatures of -268 degrees Celsius, approaching absolute zero. And it’s rather unusual to be working on a machine with 27km circumference yet demanding accuracy to 0.8 microns (0.0008mm) from us!”

The assemblies are huge, 15m long, each weighing more than 32 tonnes. They each are positioned within an accuracy of a human hair along the 27 km length, with Fine Tubes supplying products to cool these assemblies.

The tubes form part of the beam screens, which are inserted into the beam pipes of the collider’s superconducting magnets.  They had to be laser-welded onto the beam screens, which demanded exceptionally low levels of impurity inside and out, with the inner walls needing to contain the low temperature and outer walls requiring high quality laser welding without hot cracking.

Dr Fletcher explains: “In most industrial applications, you might expect quality testing on 5% to 20% of product. For CERN it had to be 100%. There is no room for error.”