Design and Structural Analysis of a Welding Jig for Part Family Assembly of the Top and Lower Brackets of a Railcar

The need to localize the manufacturing of rail car in South Africa has prompted the need for the design and prototyping of various components of a rail car, with a view to expedite the revenue generation of the country and create job opportunities for the vibrant youths of the country. In light of this, this paper presents a detailed design and simulation of a mechanically-operated welding jig system, capable of effectively joining individual subcomponents of top bracket components of a rail car together. The welding jig system, capable of meeting the design requirements, was conceptualized and drawn using ANSYS Computer Aided Design (CAD) software. The results of the stress simulations on the top brackets to be welded, were carried out in the ANSYS environment. The results show that the jig can hold the workpiece without failure or workpiece distortion after the addition of the spacer support system to the side plates of the jig system. The stress induced with the addition of the spacer was found to reduce 15%. This implies that the addition of a spacer can minimise the stress induced in the workpiece due to the clamping force. The results of heat flux and thermal effect simulations on the top brackets, revealed that there was high penetration of heat on the majority of the top brackets surface during welding operations. However, the thermal effects of this welding operations had no effect on the quality of the individual components of the top brackets been joined together during the welding operation. This study adds to the understanding of the development of work holding systems and will assist the rail car manufacturing industries in their quest for component’s localization.