Metal oxide arrester is widely used in power system

but in its operation process

failure in O-shaped rubber sealing ring between cover plate and porcelain bushing may appear due to environmental factors. In order to improve the reliability of sealing structure of metal oxide arrester

a sealing structure consisting of two O-rings with air pressure cushioning function is proposed in this paper. A three-dimensional MOA model and a simplified equivalent model of sealing structure are established by the COMSOL finite element analysis software. Thermal-fluid-solid coupling simulation of typical sealing structure and multi-stage sealing structure is carried out

and the contact stress and von Mises equivalent stress of the two structures are analyzed. The experimental results show that the contact pressure of the multi-stage sealing structure and the typical sealing structure is greater than the internal pressure of MOA

so the effective seal can be achieved. Under the same environmental conditions

the multi-stage sealing structure has the function of air pressure buffer

the von Mises stress is smaller than the typical sealing structure

and it can buffer the seal ring stress change caused by the temperature change after the factors of sealing reliability and structure size are taken into consideration

meanwhile

the two-stage sealing structure has the comprehensive advantages of compact structure

good moisture-proof performance

and appropriate redundancy.