Analysis on Fracture Reasons of Rectangular Hanging Plates of Hanging Fittings in the 220 kV Electric Transmission Line

A fracture accident of the rectangular hanging plates of hanging fittings occurred in a 220 kV electric transmission line. Based on the analysis of the accident background, through the macroscopic inspection, load analysis, scanning electron microscope and spectrum analysis of the fracture, the fracture reasons were analyzed from the aspects of the connection type, operation environment, material quality condition, and so on. The results show that:there were some cracks in the rectangular hanging plates during manufacturing process; under the combined action of corrosive medium and high wind, cracks propagated constantly, and eventually led to the corrosion fatigue fracture of the rectangular hanging plates. Finally, some preventive measures were proposed according to the fracture reasons.