Design of high integrity nuclear handling equipment
Following very positive feedback for substantiation work provided on similar previous projects, Eadon Consulting were requested by a large nuclear processing facility to provide the design and substantiation for a piece of high integrity nuclear handling equipment.
Eadon Consulting were responsible for the design of the structural and mechanical components of the high integrity nuclear handling equipment. The equipment was required to be robust against a number of operational and fault load cases, as well as a seismic (earthquake) event. Design of the structures and mechanisms was to BS2573-1 and BS2573-2 (Rules for the Design of Cranes). Seismic analysis was undertaken in accordance with ASCE-4-98 (Seismic Analysis of Safety Related Nuclear Structures).
Eadon started out by looking at the initial design of the equipment and then moved forward into the detailed design phase of the project. Both the design and substantiation processes ran in parallel, to ensure that the proposed design met the defined design standards, the user requirements were being fulfilled and all safety functional requirements (SFR’s) were being achieved. The structural components were designed and substantiated using a finite element (FE) model in ANSYS APDL, including a response spectrum analysis to assess behaviour of the global structure under seismic loading. The mechanical components were designed and substantiated using hand calculations in accordance with ASCE 4-98, which took input loads from the FE model.
The team also carried out seismic assessments of a separate component sitting on the equipment to check its rocking stability. This was initially using hand calculation guidance from ASCE 43-05 (Seismic Design Criteria for Structures, Systems and Components in Nuclear Facilities) to assess the response of an unanchored rigid body under seismic loading. A seismic time history analysis was then used to derive secondary response spectrums to enable the team to demonstrate stability under a design basis event (DBE), as well as gauge margins against a beyond design basis event (BDBE).
A complete 3D CAD model was produced of the equipment, from which full detailed manufacturing drawings of all the components were produced as well as general assembly drawings.
In line with the requirements of the nuclear sector, the quality required of all reports, calculations and technical drawings is very high; Eadon Consulting have received very high praise from the client for both the content and the presentation of work produced.