The main insulation of the RIF bushing is the resin impregnated fiber dry capacitor core. The capacitor core is made of glass fiber with high insulation performance, impregnated with ultra-low viscosity high temperature resistant epoxy resin, wound and overlapped by microcomputer controlled winding equipment according to geodesic to form an insulation layer, and the capacitor screen is made of semiconductor conformal material. The insulating layer and the capacitor screen are alternately wound and arranged at intervals, and the pure solid capacitor core is made by high temperature curing. The connecting flange is made of high-strength aluminum alloy and glued with the capacitor core. The climbing umbrella skirt is bonded to the surface of the capacitor core by silicone rubber injection molding to form an organic whole with the capacitor core. Since its invention by the company in 2001, the product has won high praise from the majority of users for its advantages of small volume, light weight, maintenance free, high mechanical strength and safe and reliable operation. The application has increased year by year. At present, the cumulative operation has reached more than 100,000 pieces.