Numerical simulation and experimental study on electromagnetic crimping of aluminium terminal to copper wire strands

Abstract

Crimping of terminals to wire strands is crucial in electrical power transmission system. It has been reported that, in electrical inter connections, 60% failure takes place in crimped junctions. Improving crimped connections can decrease the resistance to the current flow through terminals, reduced power loss, sparks, and over-heating in the joints etc. To overcome these problems occurring in conventional crimping process a novel technique for effective wire crimping has been proposed in this paper. A strong pulsed electromagnetic field was used in wire crimping of aluminum terminal with copper wire. Numerical simulations were carried out using LS-DYNA™ software in the electromagnetic module. Its results were utilized to design the coil and to find the optimum discharge voltage required for uniform deformation of terminals. Experiments were carried out at optimized discharge voltages obtained from the numerical simulation results to demonstrate the feasibility of electromagnetic wire crimping process. Effect of the threaded and plain profile of crimped terminals was investigated. Results like terminal deformation, cross-sectional analysis, contact resistance, pullout strength and hardness testing were carried out. This work will be helpful to the industries where wire crimped connections are used in large numbers.