According to a 220 kV porcelain pillar circuit breaker pillar porcelain sleeve crack problem

experimental methods such as macroscopic inspection

crack morphology analysis

energy spectrum detection analysis

X-ray diffraction detection

metallographic analysis

mechanical load test

and finite element analysis are used to analyze the cracked pillar porcelain sleeve.The results show that there is a significant eccentricity in the bonding area of the porcelain sleeve

which would generate a significant additional bending moment on the pillar porcelain sleeve under the self weight of the circuit breaker.At the same time

due to the uneven thickness of the cement bonding

significant internal stress would be generated in the bonding area when it is damp or expanded due to significant temperature changes

leading to the crack of the pillar porcelain sleeve.