Experimental investigation on tube flaring with a rotating tool

As the automotive industry becomes increasingly competitive, manufacturers are striving to design the lightest, most fuel-efficient vehicles to capture the market. To achieve this mission, the material processing techniques used in vehicle manufacturing must be investigated further. One such critical technique is sheet metal forming, which creates parts that account for a large percentage of the total vehicle weight. Many of these sheet metal parts make up the structure of the vehicle and are constructed from thin-walled tubes. To manufacture these thin-walled tubes into the desired shape, one of the main techniques is tube forming which can expand or reduce the tubes' diameters to the desired dimension. One specific tube forming technique is the flaring process which is typically performed at the tube end. In this paper, the tool rotation at its flaring axis was considered. The analysis of the expansion ratio, strain path, and failure limit was also performed along with experimentation. Frictional effects were considered. It was observed that varying the rotational speed of the flaring tool influenced the ability of the tube to flare. The expansion ratio can be maximized with a decreased amount of friction, a lower rotational speed of the flaring tool, and with an increase in tool velocity.