The presentation begins with a brief overview of my early projects, including cryogenic work in the space sector, research, and activities at CERN. The presentation then focuses on the design of compact, high-effectiveness counterflow cryogenic heat exchangers for space and remote-cooling applications, including their manufacturing and performance assessment within a remote-cooling system prototype.

The second part of the presentation focuses on the cryogenic commissioning of the Inner Triplet (IT) String. As part of the High-Luminosity LHC (HL-LHC) upgrade, the existing inner triplet magnets will be replaced by new Nb?Sn superconducting magnets operating at 1.9 K in pressurised He II. The magnets are powered by a cold-powering system based on MgB? and high-temperature superconductors (HTS). The IT String is a test bench that replicates the 60 m-long magnet assembly and its associated systems, enabling validation of their collective behaviour and providing valuable operational experience ahead of the installation and commissioning of the magnets in the HL-LHC tunnel.

The presentation will cover the key phases and main findings from the first HL-LHC-like operational cycle of the IT String, including cooldown, cryogenic tests such as heat-load measurements and bayonet heat-exchanger characterisation, magnet powering and quenches. The next steps towards the second operational cycle will then be outlined, followed by an overall perspective on the experience gained in the field of cryogenics.
 

Keywords
Cryogenics|Commissioning|HL-LHC|IT String|Space