| The epoxy resin insulating material cured by acid anhydride has good dielectric properties,and it is the main material for high pressure basin insulator pouring.However,the actual strength of epoxy resin/anhydride curing product is less than 1/10 of theoretical strength,which is mainly due to the existence of larger and uneven distribution of residual stresses in cured products.The existence of residual stress will make the basin insulators in the actual production process more vulnerable to micro cracks,interface delamination and other defects,endangering the safe operation of GIS equipment.Epoxy/anhydride curing system needs to be at a high temperature to curing reaction,the curing system of poor thermal conductivity,will produce uneven temperature field distribution in the curing process,the curing system of uneven contraction,then the formation of residual stress,the residual stress is one of the main reasons for force generation.In addition,the production of high pressure basin insulators often uses epoxy resin to adda-Al2O3 to improve the mechanical strength of the insulating material.With the addition of Al2O3 particles,the problems of dispersed uneven and particle agglomeration will be introduced,and the internal stress concentration will be formed in the epoxy resin curing system.In this paper,a variety of epoxy/anhydride curing system were prepared in this paper,the electrometric method the residual stress measurement of epoxy resin curing system,analysis and comparison of the different parts of the system of internal curing residual stress difference,study the influence factors of the residual stress of the cured product.The epoxy resin nanocomposite coating with super hydrophobic effect was prepared,and the related experiments of liquid fouling and surface flashover resistance were carried out,and the experimental model was established and simulated.The main contents of the paper are as follows:(1)The epoxy/anhydride curing system of insulating materials was described.The research background,significance and the basic characteristics of bisphenol A epoxy resin/anhydride curing agent were introduced.The epoxy resin and the anhydride reaction,curing reaction principle in two aspects of curing reaction of tertiary amine accelerator under the action of the two were analyzed.According to the characteristics of the curing reaction of epoxy resin,the cause of residual stress in the curing process of the whole system was analyzed.(2)The variety ratio of epoxy/anhydride curing system were prepared,the epoxy resin samples were measured and the residual stress,analysis and comparison of the different parts of the internal curing material and various residual ratio of cured epoxy resin stress,study the influence of cooling mode on the residual stress of the cured product.The residual stress of epoxy resin cured materials with different epoxy values was compared.The residual stresses were compared in the epoxy resin curing system with the addition of micrometer α-Al2O3 filler with different additions.The test results show that the residual stress in the sample with the distance to the center of the increase in the minimum surface;under different cooling conditions,the cooling medium thermal conductivity is high,the cooling rate is fast,the greater the residual stress;solid epoxy resin curing system of internal residual stress is lower than the liquid epoxy resin;micron α-Al2O3 particles added in an amount less than 300 copies,the residual stress decreases with the increase of the amount of.(3)Epoxy/anhydride/nano-silica composite coating was prepared,the effects of liquid contamination in epoxy resin on the surface of the composite motion,the collision liquid epoxy resin composite coating along the surface of the electric discharge test,morphology of epoxy resin composite coating on the surface,the flashover voltage,leakage current the measurement surface,calculated the model simulation test.The epoxy nanocomposite coating has a certain ability to prevent surface flashover.When the liquid contamination happens on the surface,it will first spread and sputter,and then shrink back.It will adhere to the surface of the coating at a certain contact angle.This process makes the most of the droplets bounce,affect the droplet adhesion fraction of the surface flashover is not large,so the whole of surface flashover has certain protective ability,and has potential application value in engineering. |
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