In the sandstorm environment of Lanzhou-Xinjiang railway line

the collision between sand particles and the sheath edge of epoxy insulator can cause the edge erosion of the sheath

and the creepage distance of the insulator decreases

which will increase the probability of insulator flashover. In closed wind tunnel tests

the wind speed was set for 57 m/s

the test time was set for 160 h

and the sand quality was 20 kg each time. The sheath edge which is parallel to the direction of incoming flow and passes by sheath diameter

is defined as 0° and 180°. The two points of intersection of sheath diameter perpendicular to the direction of incoming flow and sheath edge are defined as 90° and 270°. In the experiments

the radius reduction value of the sand particle sizes of 0.5 mm and below

0.25 mm and below

and 0.1 mm and below can be obtained in different positions of the sheath to get the sand grain size of the EMU roof edge erosion situation of epoxy resin insulators sheath. The test results show that the edge of the sheath between 90° and 270° is not corroded by counterclockwise rotation

and the wear parts are all between 0° and 90°

between 270° and 360°; When the sand particle size is less than 0.25 mm or less than 0.1 mm

the reduction value of sheath radius is less than 0.5 mm. When the sand particle size is 0.25～0.50 mm

the most severe wear occurs between 40° and 60°

and the No.7 sheath has the greatest wear. The reasons that particle size affects the degree of sheath edge erosion are that the kinetic energy before collision is different

small particles have good follow ability and large particles have poor follow ability. The most severe corrosion occurs between 40° and 60°

which is consistent with the simulation analysis results based on Finnie micro-cutting theory and computational fluid dynamics theory. The results of this paper can provide a reference for the simulation method to evaluate the corrosion degree of insulator umbrella skirt and its structural optimization design in sandstorm environment without the conditions to do the experiment.