Aging characteristics and lifespan prediction for composite insulator silicone rubber in a mountainous region environment

In this study, the aging process of composite insulator silicone rubber in a mountainous region environment was studied and a lifespan prediction model was constructed. Silicone rubber samples with various exposure times were analyzed based on the microstructure, physical properties, functional groups, and chemical environment of silicon. All experimental results corresponded to three aging stages: platform stage, upturn stage, and acceleration stage. Based on linear regression method, the peak content of Si(-O)2 and shore hardness A were selected to establish the lifespan prediction model for silicone rubber. Verification of the model showed that the residual lifespan error is less than 1.5 years. This study is based on a systematic analysis of three stages of the aging process for silicone rubber in composite insulators and obtaining critical aging parameters. Furthermore, a lifespan prediction model is proposed and validated.