Design and optimisation of the sector transport, storage and assembly tooling and procedures of the New Small Wheel for the Atlas Experiment.

Abstract

This report describes the design of the transport, storage and assembly tooling for the sectors of the ATLAS Experiment’s New Small Wheel. This tooling is to be used during the 2018 Large Hadron Collider’s shutdown, Long Shutdown 2. Comprehensive design reports following the Eurocode and CERN’s unique design environment and philosophies are presented. The NSW sector transport tool is an adaption of a previously used ATLAS EO muon transport tool, taking new sector masses, geometries and other transport restrictions into account. A safety document is provided for this tool confirming safety with regards to applied stresses in line with the Euro-code. The document also confirms lifting stability during all of the tool’s intended procedures. The assembly tool allows the sTGC components to be assembled to the Micromegas chambers to create NSW sectors for the New Small Wheel. This tool also provides a platform for repairs and adjustments to be made to the NSW sectors before installation. The NSW sector assembly station is also designed in line with the Euro-code. A floor layout allocating space for transport, assembly and storage procedures in Building 191 of the Meyrin, CERN site is provided as specified by the project requirements. An investigation confirming the validity of the finite element analysis techniques and simplifications used on the Micromegas wedges is conducted and presented. This investigation uses the results obtained from experimental thermal tests and analytical calculations of a Micromegas multiplet mock-up called the MMSW and compares them to finite element analysis results modelled to the same testing conditions. The results obtained from this investigation show that the computational results have an error of 7.6 % when compared to the attained experimental results. Consequently, because the finite element model is created in an identical manner to the one used for the Micromegas wedges, an assumption of similar errors can be applied to future simulations conducted on the Micromegas wedges, using this technique.