The mechanical and geometric properties of extruded aluminium sections depend on a number of parameters in the extrusion process, including flow and temperature evolution in the container and die. The nature of material flow during extrusion is very complex and inter-related to bearing area. Consequently, bearing lengths in production dies are determined by skilled die designers whose knowledge of material flow is based on experience. Thus, bearing lengths assignment varies from designer to designer and leads to more number of trial-and-error experiences to improve the product quality. Much of the guess work used in conventional methods can be eliminated by numerical simulation techniques and hence the use of numerical simulations becomes more interesting from the product design perspective. This paper describes the optimization of bearing lengths to obtain uniform metal flow in flat-faced aluminium extrusion die and also highlights the temperature distribution of a rail coach profile.