DTL tank installation
On Wednesday last week, the first Drift Tube Linac tank (DTL1) was transported from the HEBT loading bay to its permanent position after the MEBT section in the normal conducting linac. Installation of the 8-metre-long tank is now in progress. We will have a total of five DTL tanks, an Italian in-kind contribution to ESS via the Italian Institute for Nuclear Physics - INFN, Italy.
Conditioning the Radio-Frequency Quadrupole
RFQ conditioning was successfully completed during the summer and the cavities are now ready for beam. The start of beam commissioning is scheduled for mid-October.
Also during the summer, the ESS test stand 2 team achieved stable parallel operation of all four cavities of the first ESS medium-beta cryomodule at 2 Kelvin (-271 degrees Celsius) to the nominal RF pulse length (3.2 ms pulse width at 14 Hz) at the moderate accelerating field of 2 MV/m. This week, the technical team from Polish in-kind partner IFJ PAN with support from the ESS cryogenics team, continue the cycle of cryomodule tests, to include full RF power and cooldown of cavities to 2K.
RF power tests
Two Spoke RF power stations are under power testing in RF cell 120 in the gallery. An RF dummy load is used. RF power tests continue in the normal conducting gallery. Tests of the RF distribution system for DTL1 have been performed, and low power tests on DTL3 and 5, which will shortly be ready for high power tests.
Inside the Target Entrance building, installation of doors, terrazzo flooring in stairwells as well as handrails is substantially completed. Installation tests are ongoing and the last security installation is now in progress. SAT3 testing – final, coordinated tests of all installed systems - starts shortly.
Completion of the ground concrete from Campus plaza to the exterior of the Target Entrance building is in progress.
Target cantilever roof and facades
Façade cladding has progressed during the summer: for the Target Entrance building and Experimental Hall 1 front and gable facades the steel panels are in place. Façade works are now ongoing at the front of the Target building, above the Dog Leg on the A2T building. All facades are scheduled for completion in September.
The cantilever roof steel structure is completed.
Adjustments to the cantilever roof cladding on the south side (D01) is completed and cladding with panels of aluminium lamellae will progress with the protruding roof structure over D08 lab/Target Entrance, where brackets are already in place, and the area above Transport Hall. The last area to be completed will be at the east end, above A2T. The entire roof cladding is scheduled to be completed by the end of October.
Works continue with floor valves, from high bay to the process and maintenance cells of the Active Cells. The platform for the upper intrabay door, separating the two cells, have been lowered through the hatch opening on high bay level.
Installation of concrete blocks for the east sector bunker inside Experimental Hall 1 is ongoing. A Selene guide – the first part of the ESTIA instrument that is built-in inside the bunker wall, is already in place. The installation of this curved wall will be completed in September.
Handrails for the walkway steel bridges along the walls in the two short instrument halls are in place. Some touch-up painting works remain, as well as the final lightning installations on roof level.
Reinforcement of the runway for the bunker cranes are ongoing. Bunker cranes will be installed later this autumn on both sides of the Monolith, just in time to be tested and commissioned before final handover from Skanska to ESS.
End of construction and planned handovers to ESS
On 20 August the sectional handover of the completed Waste Treatment Facility building took place, officially in a Sectional Handover Meeting (SHME) between Skanska and ESS Facility Management on Friday afternoon. The building will be operated by the ESS Environment, Safety, Health & Quality (ESH&Q) division.
The second part of the Beamline Gallery, closest to Experimental Hall 2, is subject to sectional handover to ESS on 13 September.
Final handover inspections for the entire construction project will start in the second half of November, with final handover and the end of the construction project scheduled for 21 December 2021.