The HL-LHC Cold Powering Systems transfer the current from the power converters, located in the new underground galleries, to the superconducting magnets of the HL-LHC Inner Triplets and Matching Sections at Point 1 and Point 5. Eight systems of two different types will be installed in the HL-LHC underground as from mid-2027. Each of these systems relies on Superconducting Links, based on novel MgB₂ technology, operated at up to about 20 K and spanning a length of up to about 120 meters. The High Temperature Superconducting (HTS) current leads, which provide the electrical transfer from room temperature to about 20 K, are located close to the power converters inside compact and ad-hoc designed cryostats called DFHs. The main functionality of the DFHs is to host the current leads and the MgB₂ cables that exit the Superconducting link as well as the associated electrical splices. This is done via mechanical structures that confine and guide the helium gas cryogen - entering the DFHs at about 20 K and exiting at room temperature - and provide the required vacuum insulation.

While the DFH cryostats were designed at CERN, the manufacturing of the series components is taking place in Sweden under the coordination of Uppsala University. This is done via a successful collaboration agreement between CERN and Uppsala University, signed in early 2022. The complex mechanical components are manufactured both at the Mechanical Workshop of the University of Uppsala and in the Swedish industry - RFR Solutions AB, based in Landskrona. After manufacturing, the components are delivered to CERN, where they are assembled together with the current leads.

The full engagement and expertise of the collaborators and the successful technology transfer from CERN have enabled an efficient start of the activity. Technology transfer includes vacuum technology and associated leak testing as well as metal forming and welding expertise. As of today, all mechanical components needed for the first DFH series cryostat are manufactured and quality controlled, and they are ready to be delivered to CERN. The experience gained with this first production should enable completion of the contract by end of February 2024, when the components for the nine cryostats (eight series systems plus a spare) will have been manufactured.