Failure analysis of Gimbal type expansion joint carrying flue gases

Expansion joints used to absorb any misalignment due to positioning axial angular or due to thermal expansion of pipes. In large steel reduction plants corex process is implemented. In corex process all compressed hot gases reused and are carried to each station by pipes. To ensure safe working with these hot pressurized gases expansion joints used in piping system. Expansion joint provides flexibility to piping systems. Different expansion joints can be used to give flexibility in different direction like axial, angular and lateral. Aim of this project was to investigate the failure and modify the design of expansion joint used in steel plant. Finite element method is used for modal and Frequency response analysis. Modal analysis results which are basis for the frequency response analysis are validated with the analytical results. Fatigue life is also calculated considering maximum and minimum stresses from FRF analysis. Frequency response is considered for analysis based on failure pattern. Pulsating frequency of compressor is considered as the excitation frequency for expansion joints. After analyzing the results from the frequency response analysis modifications implemented from EJMA standards. All implemented modification are reanalyzed. Modification with reversed sleeve is found suitable for desired working.