ASME Section VIII, Boiler & Pressure Vessel Code provides guidelines for designing, manufacturing & inspection of pressure containing components. Design by rules and design by analysis are the two parts for design and validation of those components. ASME guidelines provide numerical analysis assessment procedure to develop the structural component against plastic collapse and local failure. In this paper, the design by analysis approach is adopted for validation of Bonnet design (channel head), which is the integral component of shell-tube heat exchanger package having fluid inlet and outlet ports. The bonnet must confirm the ASME guidelines as a design acceptance criterion. Stress analysis of bonnet for defined loading conditions is carried out using Finite Element Analysis (FEA). The objective of this FEA exercise is to implement such approach to validate the bonnet structural strength accordance to ASME in lieu of time consuming and expensive typical physical hydrostatic proof testing approach. The component assembly is improved to achieve conditions close to reality in order to enhance FEA results. The obtained results for stresses are compared with the allowable values. The stress linearization method is described briefly and demonstrated on proposed component. The stress linearization method used to classify the stresses, eventually the resulting stresses are categorized according to code. To verify elastic analysis approach for proposed component having geometrical and material non-linearity, non-linear limit load analysis is performed.

Keywords: Bonnet design, Design by analysis, Limit load, Stress linearization.