Insulator core rod

1. Appearance characteristics
The mandrel is a cylindrical or slightly tapered rod-like structure with a smooth surface and green or olive green color. The length and diameter of the core rod vary according to the voltage level of the insulator and the environment in which it is used (such as transmission lines, substations). Some mandrels have metal connectors or reserved holes at both ends for connection with metal accessories. Core rods of different sizes and specifications have different modular and standardized designs and can be adapted to different voltage levels.

2. Main materials
The main material of the insulator core rod is glass fiber reinforced resin. Specifically, alkali-free glass fiber is used as the reinforcing material, which provides high strength, high modulus, corrosion resistance, and fatigue resistance. The matrix resin uses epoxy resin or vinyl ester resin to provide adhesion, weather resistance, and electrical insulation. The core rod has the advantages of high mechanical strength, excellent fatigue resistance, corrosion resistance, UV resistance, moisture and heat resistance, light weight, good electrical insulation properties, and non-magnetic and no eddy current loss.

3. Core role
Insulator core rods perform multiple functions in power systems. The first is the mechanical support function, which bears the mechanical load that the insulator undergoes during operation, including wire tension, wind load, ice load, self-weight, etc. Suspension insulators mainly bear tensile force, while pillar insulators may bear pressure or bending force. The second is electrical insulation. Although the main insulation is provided by the external silicone rubber shield, the core rod itself also has good insulation properties to prevent internal conduction. It also forms a whole together with the external sheath and metal accessories to ensure the long-term stable operation of the insulator in harsh environments. The core rod also has excellent weather resistance and anti-aging properties, and its service life can be as long as 30 years, far exceeding traditional porcelain or glass insulators.

4. Application fields
Insulator core rods are widely used in high-voltage and ultra-high voltage transmission lines, including voltage levels of 110kV, 220kV, 500kV and 1000kV ultra-high voltage. It is also widely used in substation equipment, such as pillar insulators, bushings, isolation switch insulators, etc. Insulator core rods also play an important role in wind power generation, rail transit, rail transit traction power supply systems, and in harsh environmental areas such as coastal areas, high pollution, high humidity, and high altitude.