Finite element simulation of the railway coach shell assembly process

Thin sheets covering the skeleton of the railway coach shell undergo severe deformations during the manufacturing process. A comprehensive three-dimen sional finite element model has been developed to simulate the manufacture of the complete coach shell assembly. The analysis has been extended by var ying the camber, the self-weight of the coach shell and the thickness of th e side panel sheet, to identify the exact cause for the coach shell deforma tion. Camber, a positive deflection given intentionally to compensate for t he sagging of the coach, is one of the very important design parameters in the manufacture of railway coaches. A three-step analysis is suggested to c alculate the correct camber. It has been demonstrated that the camber value arrived at by the conventional method is not accurate and a correction fac tor is required. The welding of the side panel to the underframe is a cruci al determinant of camber. This issue is addressed through a comprehensive f inite element analysis.