Composite insulators mainly by unidirectional glass fiber-reinforced resin with Stubbs rods to bear mechanical loads

Composite insulators mainly by unidirectional glass fiber-reinforced resin primer Stubbs rods (commonly known as a mandrel) to bear mechanical load. The withdrawal of FRP most prominent features ie high tensile strength and specific strength. The withdrawal of the glass fiber in the axial direction of the forward bearing arrangement, it has a high axial tensile strength, generally up to 1000 MPa or more. Thus diameter of only 18 mm of lead pull rod, the tensile breaking strength can reach more than 250 kN. Also, because the density of lead pull rod generally is 2.0 g / cm3, so its strength (tensile strength to weight ratio) is 5 to 6 times the high-quality carbon structural steel. The withdrawal of high-strength, high specific strength characteristics, it is the composite insulators of high strength, light weight, thin rod diameter foundation.

Although glass fiber composite insulators entirely on The withdrawal of mechanical load to bear, but the strength of the mandrel does not mean strength of composite insulators, this is because the load must pass through the mandrel end fitting of the insulator to the tower and transmission lines and wires are connected. The ends of the connection must be the highest concentration of mechanical stress, a different connection structure will lead to different stress concentration, and therefore the mechanical strength of the composite insulators is actually greater than on the mechanical strength of the mandrel, but its the mechanical strength of the connection end portion, that is, using the strength of a mandrel. Using the same mandrel connection structure of different composite insulators, the mechanical strength is different, and therefore the use of the strength of the mandrel is different.