Residual stress evaluation within a crimped splice connector assembly

In power transmission, connectors play an important role in the efficiency and reliability of the system. Due to the increase of power demand and lack of new infrastructure, existing overhead power transmission lines often need to operate at temperatures higher than the original design criteria. However, this had led to the accelerated aging and degradation of splice connectors, which has been manifested by the formation of hot-spots that have been revealed by infrared imaging during inspection of transmission lines operating at elevated temperatures. The implications of connector aging is two-fold: (1) significant increase in resistivity of the splice connector (i.e., less efficient transmission of electricity) and (2) significant reduction in the connector clamping strength, which ultimately results in separation of the power transmission line at the joint. Therefore, the splice connector has become the weakest link in the electric power transmission infrastructure. The compressive residual stresses induced by the crimping process within the splice provide the clamping forces to secure the conductor and therefore, the determination of the state of residual stresses in splice connectors is a necessary requirement to provide an accurate estimate of their service lifetime. This paper presents a protocol of utilizing finite-element analysis and neutron scattering experiments for evaluating the residual stress fields within a crimped single-stage splice connector assembly. Copyright ASCE 2007.