Optimisation of the crimping process of a metal end-fitting onto a composite rod

The purpose of this research is to find optimal crimping conditions involved in the assembly of composite insulators. To achieve this goal, a configurable nonlinear numerical model has been designed in order to study three main parameters that characterize the crimping process: the clearance and the friction coefficient between the rod and the end-fitting, along with the hardness of the fitting. It was found that the roughness was one of the most sensible parameter implied in the crimping process. Moreover, the ultimate tensile strength tends to decrease with an increase of clearance. Finally, the end-fitting will deform less since the hardness is high: the assembly will be weak and premature sliding will occur. Combining the effect of these parameters, experimentally 20% better results in term of mechanical performance of the composite insulator were obtained.