An Evaluation of the Assemblability of Two Novel Assembled Camshaft Configurations by Tube Hydroforming

Two configurations of assembled camshafts characterised by isometric-trilateral and logarithmic spiral cross-sectional profiles of the cam-bores are proposed and assembled via tube hydroforming (THF). After being assembled, the contact status between the hollow shafts and cam-bores on the centre cross-sections of the assembled camshafts were investigated. The maximum fit clearances and the effective contact lengths were then measured to evaluate the assemblability of the camshafts by THF. The results indicated that the two novel assembled camshafts with isometric-trilateral and logarithmic spiral contact profiles demonstrate good, but differing assemblability-the former exhibits superior assemblability to the latter and smaller cam-bores display better assemblability. The assemblability could be enhanced by increasing the assembly hydraulic pressure, but this is not efficient with smaller cam-bores.