The fiber glass core is an important component of composite insulators. Composite insulators consist of internal core rods and external silicone rubber shells, except for the metal fittings at both ends. The glass fiber core rod (GFRP core rod) is mainly used to bear mechanical force.
The production of composite insulator cores involves various materials and techniques, and the following are the basic steps involved:
Impregnation: The glass fiber is impregnated with an epoxy resin mixture in a vacuum state or under a positive pressure of 4 MPa in the impregnator.
Preforming: The impregnated glass fiber is preformed through a one-time forming mold.
Secondary winding: Glass fiber impregnated with epoxy resin mixture is wound again on the surface of the preformed glass fiber at an angle of +35 degrees to the axis.
Secondary molding: The glass fiber after secondary winding is formed through a secondary molding mold to ensure a thickness of ≥5 mm.
Third winding: Glass fiber impregnated with epoxy resin mixture is wound again on the surface of the secondary molded glass fiber at an angle of -35 degrees to the axis.
Final molding: The glass fiber after third winding is formed through a final molding mold to ensure a thickness of ≥5 mm.
Curing: The finally molded glass fiber is placed in a high-temperature curing box and cured at a temperature of 150°C – 160°C to form the core rod.
Drawing out: Using a pulling machine, the cured core rod is drawn out from the high-temperature curing box, completing the preparation of the core rod for composite insulators.
The advantage of Fibre glass composite insulators are:
Fiberglass core rods types:
