A. Palve

S. Shinde

Dr. Kiran Bhole

Abstract

Thermal expansion and vibration in piping and other equipment components are commonly observed conditions for process/power plant industry in which piping and other components are subjected to changes in temperature, pressure as well as dynamic loadings. Such temperature changes under constrained conditions may lead to differential thermal expansion and hence failure due to high thermal stresses. In such cases, Expansion joints are used to compensate for these thermal expansions/contractions in the system while sustaining the other service conditions. Expansion joints are designed on the basis of various codes/standards like American Society of Mechanical Engineers (ASME) (appendix 26), Expansion Joint Manufacturers Association (EJMA), European Standard (EN standards), Tubular Exchanger Manufacturers Association (TEMA) etc. these codes provide the design for most essential part in expansion joint (bellows). But it is found that the expansion bellows get overdesigned due to improper selection procedure. So still there is scope for optimisation in selection of expansion bellow. Considering this need a parametric study based on a practical example was done to find the effective design parameters. Based on the results of the parametric evaluation as well considering the design codes and standards, an iterative logic was developed for design of expansion bellows and then further it is coded as MS EXCEL macros. This logic was validated with the FEA to check its validity. This logic can provide an optimum design of expansion bellow generated using EXCEL macros program best suited for given input conditions

Keywords- Expansion joint, Parametric Study, Optimization of Bellows, Algorithms, Pressure Vessels