The last two castings for the concrete shielding around the Dump to Target area will take place this week. Assembly of sandwich panels is ongoing on both sides of the Active Cell high bay, and roof works will soon follow. The crane beams for the temporary crane will be extended from the Utility/Monolith so that the crane can move all the way to Transport Hall. It is scheduled to be operational for the full length of the high bay by the end of April, in time for the ESS Monolith vessel installation on site.
The roof trusses for Experimental Hall 2 are currently under adaptation, in order to fit the steel structure already in place. Mounting is expected to start next week. Experimental Hall 1 superstructure is also scheduled to start beginning of next week. Steel for the second part of the Beamline Gallery will follow in April.
Construction of the 'control hutch' for the BIFROST instrument has been completed. It will be used as an office for future scientists when ESS goes into operations, and may also be used in the near future for planning and preparations for the installation teams that are working in the area. This is the first of up to seven control hutches to be built in the Beamline Gallery area. Precast elements and steel for the walls and roof structure of the NMX cave are currently being manufactured by the supplier. Installation on site is set to start before the end of March. The cave, which will be about seven metres tall, will contain a small overhead crane and a safety door, to enter the cave through a chicane, and all surfaces will be painted with epoxy. Construction of the NMX cave is expected to be completed by June 2020.
Work has also been carried out in the Beamline Gallery as part of a common shielding project. The goal is to establish a common procedure that applies to all shielding blocks for all beamlines at ESS. First the floor is marked, then base blocks are put in place, and lastly surveying is performed to ensure the blocks are aligned within strict tolerances.
The beam dump and T-copper has been successfully positioned inside the beam dump cave, and covered with steel and concrete shielding. At the same time, cooling water pipes have been installed inside the cave, all pressure tested and x-rayed.
Work is ongoing with cable terminations in the first 50 metres of the Accelerator. Preparations to move the first ESS serial-produced modulator from Test Stand 3 to its permanent place in the normal conducting section of the Gallery. The purpose of a modulator is to convert incoming high voltage to electrical pulse power, suitable for the klystrons - a power amplifier that, in turn, converts the power to radio frequency waves, fed down to cavities in the Accelerator - via waveguides installed through the stubs. Each of these state-of-the-art, in-house-developed modulators can supply the power needed for four klystrons.