Speaker
Description
ESS Bilbao reports the mechanical design and manufacturing preparation for a spectrometer vacuum vessel intended for installation in the STS. Work progressed from the conceptual stage to a final 3D model submitted for the Preliminary Design Review (PDR), supported by a comprehensive programme of mechanical verification and manufacturing studies. The mechanical verification comprised extensive finite-element analyses — geometry-optimising FEA runs, FEA validation of the optimised overall design, initial seismic evaluation, anchoring studies, bolted-flanges (bolt sizing and count), positive-pressure assessment and lifting/handling assessments — which together established the structural layout, anchoring strategy and flange design necessary to meet alignment and load requirements during installation and operation.
A manufacturability study has been carried out in collaboration with Asturfeito. This study validated a segmentation scheme for transport and on-site assembly, identified suitable welding methodologies and critical machining regions, and defined the testing, cleaning and packing procedures required for fabrication and delivery. Design updates introduced to facilitate fabrication and installation include a SS316L-panel layout for the external-wall, reshaping of polyethylene panels to limit manual handling to under 23 kg (50 lb), and recommendations to increase pit clearances by approximately 15–20 cm per side. The design package also records the requirement to follow ASME Section VIII fabrication protocols (despite the vessel not being code-stamped) and includes quality-control and vacuum-testing provisions.
Taken together, the design optimisation process, final analyses and manufacturability activities deliver a validated design and a complete manufacturing/assembly package that enables a controlled, lower-risk transition to fabrication while satisfying both spectrometer instrument requirements and STS site constraints
Keywords: vacuum vessel; spectrometer; STS; FEA; finite-element analysis; manufacturability; segmentation; welding; installation; ASME Section VIII