Target Station 1 (TS1) has run for over 35 years without significant maintenance or development work. The TS1 project seeks to upgrade key elements of the target station, with the actual work taking place during the long shutdown in 2021/22.

Over the last few years, the different pieces of the target, reflector and moderator (TRAM) assembly have been brought together. This has been happening in parallel to the removal of the old equipment from the target services area and from inside the remote handling cell.

The TRAM build has involved the jigsaw-like construction of the £3.4 million 13-piece reflector and the electron beam welding of ten individual plates of tantalum-clad tungsten to form the target. The final piece to arrive to complete this complex puzzle was the cryogenic hydrogen moderator.

Although it looks simple from the outside, the moderator contains a complicated collection of specially machined components, intricately assembled and sealed into the final unit, as shown in the rendered image on the left​. To prevent against failure in the future, the design of the moderator has been adjusted slightly, while keeping the design improvements made during the 2008 long shutdown.

This was more challenging than the team expected, explains Dan Coates; “as we couldn't find the plans for the original moderator. They were probably kept on paper somewhere when the first design happened in the 1980s!"

Now that the moderator has been delivered, the team can now assemble and accurately align the new TRAM, ready for installation onto the (now empty) target trolley.