Permanent Shielding for Target Monolith Vessel Completed

Inner shielding done
All shielding blocks are in place inside the Target Monolith vessel, leaving just the space for the Target Wheel and other technical components. Image: Krister Blomberg/ESS

Nestled within the core of the Target building lies the Monolith, a cylindrical structure that serves as the home of the neutron source. To ensure the safety of the surrounding areas during operations, shielding is required. Building upon the completion of the outer shielding last year, ESS has achieved another major milestone by successfully installing the inner shielding system.
This complex installation took place inside the Monolith vessel, provided by Spanish in-kind partner ESS Bilbao.

Lifting block

Heavy lifting operation as the last two shielding blocks are lowered into the Monolith vessel.

Image: Ulrika Hammarlund/ESS

The final stainless-steel shielding block for the permanent shielding of the Target Monolith vessel has been successfully lifted into place. This accomplishment represents a significant milestone in the construction process, laying the foundation for the installation of major Target system components. The collaborative efforts of the Target installation, ESS Rigging, ESS Survey, Alignment and Metrology and ESS Vacuum teams, along with the supplier Asturfeito (Spain) and welding contractor Techweld (Sweden), have made this achievement possible.

The installation of the inner shielding blocks started last summer: in total 32 major blocks, whereof eight blocks with cooling pipes integrated into the shielding structure, and a number of filler blocks were placed to complete the shielding system.

This operation was carried out within a controlled cleanroom environment. Executed with meticulous precision, the tolerance for the critical blocks placed close to the Target Wheel were placed within a tolerance of ±0,75 millimetres.

Preparing for the Next Phase

With the shielding now in place, the Target Monolith area is primed for the installation of crucial components, including the Target Wheel. The subsequent step involves the test installation of blocks above the wheel, the moderator, and the Proton Beam Instrumentation Plug.

The inner shielding fills the space within the Monolith vessel that is not occupied by equipment. The focus now shifts towards preparing the major technical components for installation within the vessel. The key components - the Target Wheel, shaft, drive unit, Moderator/Reflector Plug, Target Monitoring Plug - are all on the ESS site in Lund, undergoing preparations for installation. The Proton Beam Instrumentation Plug will be delivered from ESS Bilbao this autumn.

This movie clip shows the installation of the very last inner shielding block.

Videography: Ulrika Hammarlund/ESS